From 76f184c50b73e7006800235b78c83b01fa399637 Mon Sep 17 00:00:00 2001 From: don bright Date: Mon, 11 Feb 2013 19:10:52 -0600 Subject: [PATCH] upgrade lodepng to new version. remove malloc from imageutils --- src/imageutils-lodepng.cc | 27 +- src/lodepng.cpp | 5503 ++++++++++++++++++++----------------- src/lodepng.h | 1880 ++++++------- 3 files changed, 3806 insertions(+), 3604 deletions(-) diff --git a/src/imageutils-lodepng.cc b/src/imageutils-lodepng.cc index a0347028..cd104d68 100644 --- a/src/imageutils-lodepng.cc +++ b/src/imageutils-lodepng.cc @@ -2,25 +2,16 @@ #include "lodepng.h" #include #include +#include +#include +#include bool write_png(std::ostream &output, unsigned char *pixels, int width, int height) { - //encoder.settings.zlibsettings.windowSize = 2048; - //LodePNG_Text_add(&encoder.infoPng.text, "Comment", "Created with LodePNG"); - size_t dataout_size = -1; - bool result = false; - unsigned char *dataout = (unsigned char *)malloc(width*height*4); - if (!dataout) { - perror("Error allocating memory while writing png\n"); - return result; - } - LodePNG_encode(&dataout, &dataout_size, pixels, width, height, LCT_RGBA, 8); - try { - output.write( reinterpret_cast(dataout), dataout_size ); - result = true; - } catch (const std::ios_base::failure &e) { - std::cerr << "Error writing to ostream:" << e.what() << "\n"; - } - free( dataout ); - return result; + std::vector dataout; + unsigned err = lodepng::encode(dataout, pixels, width, height, LCT_RGBA, 8); + if ( err ) return false; + output.write( reinterpret_cast(&dataout[0]), dataout.size()); + if ( output.bad() ) std::cerr << "Error writing to ostream\n"; + return output.good(); } diff --git a/src/lodepng.cpp b/src/lodepng.cpp index 9d21668a..9003168f 100644 --- a/src/lodepng.cpp +++ b/src/lodepng.cpp @@ -1,7 +1,7 @@ /* -LodePNG version 20110908 +LodePNG version 20130128 -Copyright (c) 2005-2011 Lode Vandevenne +Copyright (c) 2005-2013 Lode Vandevenne This software is provided 'as-is', without any express or implied warranty. In no event will the authors be held liable for any damages @@ -33,11 +33,11 @@ Rename this file to lodepng.cpp to use it for C++, or to lodepng.c to use it for #include #include -#ifdef __cplusplus +#ifdef LODEPNG_COMPILE_CPP #include -#endif /*__cplusplus*/ +#endif /*LODEPNG_COMPILE_CPP*/ -#define VERSION_STRING "20110908" +#define VERSION_STRING "20130128" /* This source file is built up in the following large parts. The code sections @@ -48,6 +48,25 @@ with the "LODEPNG_COMPILE_" #defines divide this up further in an intermixed way -The C++ wrapper around all of the above */ +/*The malloc, realloc and free functions defined here with "my" in front of the +name, so that you can easily change them to others related to your platform in +this one location if needed. Everything else in the code calls these.*/ + +static void* mymalloc(size_t size) +{ + return malloc(size); +} + +static void* myrealloc(void* ptr, size_t new_size) +{ + return realloc(ptr, new_size); +} + +static void myfree(void* ptr) +{ + free(ptr); +} + /* ////////////////////////////////////////////////////////////////////////// */ /* ////////////////////////////////////////////////////////////////////////// */ /* // Tools for C, and common code for PNG and Zlib. // */ @@ -59,7 +78,7 @@ Often in case of an error a value is assigned to a variable and then it breaks out of a loop (to go to the cleanup phase of a function). This macro does that. It makes the error handling code shorter and more readable. -Example: if(!uivector_resizev(&frequencies_ll, 286, 0)) ERROR_BREAK(9924); +Example: if(!uivector_resizev(&frequencies_ll, 286, 0)) ERROR_BREAK(83); */ #define CERROR_BREAK(errorvar, code)\ {\ @@ -70,8 +89,22 @@ Example: if(!uivector_resizev(&frequencies_ll, 286, 0)) ERROR_BREAK(9924); /*version of CERROR_BREAK that assumes the common case where the error variable is named "error"*/ #define ERROR_BREAK(code) CERROR_BREAK(error, code) +/*Set error var to the error code, and return it.*/ +#define CERROR_RETURN_ERROR(errorvar, code)\ +{\ + errorvar = code;\ + return code;\ +} + +/*Try the code, if it returns error, also return the error.*/ +#define CERROR_TRY_RETURN(call)\ +{\ + unsigned error = call;\ + if(error) return error;\ +} + /* -About vector, uivector, ucvector and string: +About uivector, ucvector and string: -All of them wrap dynamic arrays or text strings in a similar way. -LodePNG was originally written in C++. The vectors replace the std::vectors that were used in the C++ version. -The string tools are made to avoid problems with compilers that declare things like strncat as deprecated. @@ -79,88 +112,6 @@ About vector, uivector, ucvector and string: -As with many other structs in this file, the init and cleanup functions serve as ctor and dtor. */ -#ifdef LODEPNG_COMPILE_ZLIB -#ifdef LODEPNG_COMPILE_ENCODER - -typedef struct vector /*dynamic vector of void* pointers. This one is used only by the deflate compressor*/ -{ - void* data; - size_t size; /*in groups of bytes depending on type*/ - size_t allocsize; /*in bytes*/ - unsigned typesize; /*sizeof the type you store in data*/ -} vector; - -static unsigned vector_resize(vector* p, size_t size) /*returns 1 if success, 0 if failure ==> nothing done*/ -{ - if(size * p->typesize > p->allocsize) - { - size_t newsize = size * p->typesize * 2; - void* data = realloc(p->data, newsize); - if(data) - { - p->allocsize = newsize; - p->data = data; - p->size = size; - } - else return 0; - } - else p->size = size; - return 1; -} - -/*resize and use destructor on elements if it gets smaller*/ -static unsigned vector_resized(vector* p, size_t size, void dtor(void*)) -{ - size_t i; - if(size < p->size) - { - for(i = size; i < p->size; i++) - { - dtor(&((char*)(p->data))[i * p->typesize]); - } - } - return vector_resize(p, size); -} - -static void vector_cleanup(void* p) -{ - ((vector*)p)->size = ((vector*)p)->allocsize = 0; - free(((vector*)p)->data); - ((vector*)p)->data = NULL; -} - -static void vector_cleanupd(vector* p, void dtor(void*)) /*clear and use destructor on elements*/ -{ - vector_resized(p, 0, dtor); - vector_cleanup(p); -} - -static void vector_init(vector* p, unsigned typesize) -{ - p->data = NULL; - p->size = p->allocsize = 0; - p->typesize = typesize; -} - -static void vector_swap(vector* p, vector* q) /*they're supposed to have the same typesize*/ -{ - size_t tmp; - void* tmpp; - tmp = p->size; p->size = q->size; q->size = tmp; - tmp = p->allocsize; p->allocsize = q->allocsize; q->allocsize = tmp; - tmpp = p->data; p->data = q->data; q->data = tmpp; -} - -static void* vector_get(vector* p, size_t index) -{ - return &((char*)p->data)[index * p->typesize]; -} - -#endif /*LODEPNG_COMPILE_ENCODER*/ -#endif /*LODEPNG_COMPILE_ZLIB*/ - -/* /////////////////////////////////////////////////////////////////////////// */ - #ifdef LODEPNG_COMPILE_ZLIB /*dynamic vector of unsigned ints*/ typedef struct uivector @@ -173,7 +124,7 @@ typedef struct uivector static void uivector_cleanup(void* p) { ((uivector*)p)->size = ((uivector*)p)->allocsize = 0; - free(((uivector*)p)->data); + myfree(((uivector*)p)->data); ((uivector*)p)->data = NULL; } @@ -183,7 +134,7 @@ static unsigned uivector_resize(uivector* p, size_t size) if(size * sizeof(unsigned) > p->allocsize) { size_t newsize = size * sizeof(unsigned) * 2; - void* data = realloc(p->data, newsize); + void* data = myrealloc(p->data, newsize); if(data) { p->allocsize = newsize; @@ -250,20 +201,13 @@ typedef struct ucvector size_t allocsize; /*allocated size*/ } ucvector; -static void ucvector_cleanup(void* p) -{ - ((ucvector*)p)->size = ((ucvector*)p)->allocsize = 0; - free(((ucvector*)p)->data); - ((ucvector*)p)->data = NULL; -} - /*returns 1 if success, 0 if failure ==> nothing done*/ static unsigned ucvector_resize(ucvector* p, size_t size) { if(size * sizeof(unsigned char) > p->allocsize) { size_t newsize = size * sizeof(unsigned char) * 2; - void* data = realloc(p->data, newsize); + void* data = myrealloc(p->data, newsize); if(data) { p->allocsize = newsize; @@ -276,8 +220,22 @@ static unsigned ucvector_resize(ucvector* p, size_t size) return 1; } -#ifdef LODEPNG_COMPILE_DECODER #ifdef LODEPNG_COMPILE_PNG + +static void ucvector_cleanup(void* p) +{ + ((ucvector*)p)->size = ((ucvector*)p)->allocsize = 0; + myfree(((ucvector*)p)->data); + ((ucvector*)p)->data = NULL; +} + +static void ucvector_init(ucvector* p) +{ + p->data = NULL; + p->size = p->allocsize = 0; +} + +#ifdef LODEPNG_COMPILE_DECODER /*resize and give all new elements the value*/ static unsigned ucvector_resizev(ucvector* p, size_t size, unsigned char value) { @@ -286,14 +244,8 @@ static unsigned ucvector_resizev(ucvector* p, size_t size, unsigned char value) for(i = oldsize; i < size; i++) p->data[i] = value; return 1; } -#endif /*LODEPNG_COMPILE_PNG*/ #endif /*LODEPNG_COMPILE_DECODER*/ - -static void ucvector_init(ucvector* p) -{ - p->data = NULL; - p->size = p->allocsize = 0; -} +#endif /*LODEPNG_COMPILE_PNG*/ #ifdef LODEPNG_COMPILE_ZLIB /*you can both convert from vector to buffer&size and vica versa. If you use @@ -305,7 +257,7 @@ static void ucvector_init_buffer(ucvector* p, unsigned char* buffer, size_t size } #endif /*LODEPNG_COMPILE_ZLIB*/ -#ifdef LODEPNG_COMPILE_ENCODER +#if (defined(LODEPNG_COMPILE_PNG) && defined(LODEPNG_COMPILE_ANCILLARY_CHUNKS)) || defined(LODEPNG_COMPILE_ENCODER) /*returns 1 if success, 0 if failure ==> nothing done*/ static unsigned ucvector_push_back(ucvector* p, unsigned char c) { @@ -313,7 +265,7 @@ static unsigned ucvector_push_back(ucvector* p, unsigned char c) p->data[p->size - 1] = c; return 1; } -#endif /*LODEPNG_COMPILE_ENCODER*/ +#endif /*defined(LODEPNG_COMPILE_PNG) || defined(LODEPNG_COMPILE_ENCODER)*/ /* ////////////////////////////////////////////////////////////////////////// */ @@ -323,7 +275,7 @@ static unsigned ucvector_push_back(ucvector* p, unsigned char c) /*returns 1 if success, 0 if failure ==> nothing done*/ static unsigned string_resize(char** out, size_t size) { - char* data = (char*)realloc(*out, size + 1); + char* data = (char*)myrealloc(*out, size + 1); if(data) { data[size] = 0; /*null termination char*/ @@ -342,7 +294,7 @@ static void string_init(char** out) /*free the above pair again*/ static void string_cleanup(char** out) { - free(*out); + myfree(*out); *out = NULL; } @@ -362,25 +314,27 @@ static void string_set(char** out, const char* in) /* ////////////////////////////////////////////////////////////////////////// */ -unsigned LodePNG_read32bitInt(const unsigned char* buffer) +unsigned lodepng_read32bitInt(const unsigned char* buffer) { return (buffer[0] << 24) | (buffer[1] << 16) | (buffer[2] << 8) | buffer[3]; } +#if defined(LODEPNG_COMPILE_PNG) || defined(LODEPNG_COMPILE_ENCODER) /*buffer must have at least 4 allocated bytes available*/ -static void LodePNG_set32bitInt(unsigned char* buffer, unsigned value) +static void lodepng_set32bitInt(unsigned char* buffer, unsigned value) { buffer[0] = (unsigned char)((value >> 24) & 0xff); buffer[1] = (unsigned char)((value >> 16) & 0xff); buffer[2] = (unsigned char)((value >> 8) & 0xff); buffer[3] = (unsigned char)((value ) & 0xff); } +#endif /*defined(LODEPNG_COMPILE_PNG) || defined(LODEPNG_COMPILE_ENCODER)*/ #ifdef LODEPNG_COMPILE_ENCODER -static void LodePNG_add32bitInt(ucvector* buffer, unsigned value) +static void lodepng_add32bitInt(ucvector* buffer, unsigned value) { ucvector_resize(buffer, buffer->size + 4); /*todo: give error if resize failed*/ - LodePNG_set32bitInt(&buffer->data[buffer->size - 4], value); + lodepng_set32bitInt(&buffer->data[buffer->size - 4], value); } #endif /*LODEPNG_COMPILE_ENCODER*/ @@ -390,7 +344,7 @@ static void LodePNG_add32bitInt(ucvector* buffer, unsigned value) #ifdef LODEPNG_COMPILE_DISK -unsigned LodePNG_loadFile(unsigned char** out, size_t* outsize, const char* filename) +unsigned lodepng_load_file(unsigned char** out, size_t* outsize, const char* filename) { FILE* file; long size; @@ -409,16 +363,16 @@ unsigned LodePNG_loadFile(unsigned char** out, size_t* outsize, const char* file /*read contents of the file into the vector*/ *outsize = 0; - *out = (unsigned char*)malloc((size_t)size); + *out = (unsigned char*)mymalloc((size_t)size); if(size && (*out)) (*outsize) = fread(*out, 1, (size_t)size, file); fclose(file); - if(!(*out) && size) return 9900; /*the above malloc failed*/ + if(!(*out) && size) return 83; /*the above malloc failed*/ return 0; } /*write given buffer to the file, overwriting the file, it doesn't append to it.*/ -unsigned LodePNG_saveFile(const unsigned char* buffer, size_t buffersize, const char* filename) +unsigned lodepng_save_file(const unsigned char* buffer, size_t buffersize, const char* filename) { FILE* file; file = fopen(filename, "wb" ); @@ -437,11 +391,6 @@ unsigned LodePNG_saveFile(const unsigned char* buffer, size_t buffersize, const /* ////////////////////////////////////////////////////////////////////////// */ #ifdef LODEPNG_COMPILE_ZLIB - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Reading and writing single bits and bytes from/to stream for Deflate / */ -/* ////////////////////////////////////////////////////////////////////////// */ - #ifdef LODEPNG_COMPILE_ENCODER /*TODO: this ignores potential out of memory errors*/ static void addBitToStream(size_t* bitpointer, ucvector* bitstream, unsigned char bit) @@ -534,9 +483,9 @@ Huffman tree struct, containing multiple representations of the tree */ typedef struct HuffmanTree { - uivector tree2d; - uivector tree1d; - uivector lengths; /*the lengths of the codes of the 1d-tree*/ + unsigned* tree2d; + unsigned* tree1d; + unsigned* lengths; /*the lengths of the codes of the 1d-tree*/ unsigned maxbitlen; /*maximum number of bits a single code can get*/ unsigned numcodes; /*number of symbols in the alphabet = number of codes*/ } HuffmanTree; @@ -556,16 +505,16 @@ static void HuffmanTree_draw(HuffmanTree* tree) static void HuffmanTree_init(HuffmanTree* tree) { - uivector_init(&tree->tree2d); - uivector_init(&tree->tree1d); - uivector_init(&tree->lengths); + tree->tree2d = 0; + tree->tree1d = 0; + tree->lengths = 0; } static void HuffmanTree_cleanup(HuffmanTree* tree) { - uivector_cleanup(&tree->tree2d); - uivector_cleanup(&tree->tree1d); - uivector_cleanup(&tree->lengths); + myfree(tree->tree2d); + myfree(tree->tree1d); + myfree(tree->lengths); } /*the tree representation used by the decoder. return value is error*/ @@ -575,7 +524,8 @@ static unsigned HuffmanTree_make2DTree(HuffmanTree* tree) unsigned treepos = 0; /*position in the tree (1 of the numcodes columns)*/ unsigned n, i; - if(!uivector_resize(&tree->tree2d, tree->numcodes * 2)) return 9901; /*alloc fail*/ + tree->tree2d = (unsigned*)mymalloc(tree->numcodes * 2 * sizeof(unsigned)); + if(!tree->tree2d) return 83; /*alloc fail*/ /* convert tree1d[] to tree2d[][]. In the 2D array, a value of 32767 means @@ -587,22 +537,22 @@ static unsigned HuffmanTree_make2DTree(HuffmanTree* tree) There is only memory for such good tree currently, if there are more nodes (due to too long length codes), error 55 will happen */ - for(n = 0; n < tree->numcodes * 2; n++) + for(n = 0; n < tree->numcodes * 2; n++) { - tree->tree2d.data[n] = 32767; /*32767 here means the tree2d isn't filled there yet*/ + tree->tree2d[n] = 32767; /*32767 here means the tree2d isn't filled there yet*/ } for(n = 0; n < tree->numcodes; n++) /*the codes*/ { - for(i = 0; i < tree->lengths.data[n]; i++) /*the bits for this code*/ + for(i = 0; i < tree->lengths[n]; i++) /*the bits for this code*/ { - unsigned char bit = (unsigned char)((tree->tree1d.data[n] >> (tree->lengths.data[n] - i - 1)) & 1); - if(treepos > tree->numcodes - 2) return 55; /*error 55: oversubscribed; see description in header*/ - if(tree->tree2d.data[2 * treepos + bit] == 32767) /*not yet filled in*/ + unsigned char bit = (unsigned char)((tree->tree1d[n] >> (tree->lengths[n] - i - 1)) & 1); + if(treepos > tree->numcodes - 2) return 55; /*oversubscribed, see comment in lodepng_error_text*/ + if(tree->tree2d[2 * treepos + bit] == 32767) /*not yet filled in*/ { - if(i + 1 == tree->lengths.data[n]) /*last bit*/ + if(i + 1 == tree->lengths[n]) /*last bit*/ { - tree->tree2d.data[2 * treepos + bit] = n; /*put the current code in it*/ + tree->tree2d[2 * treepos + bit] = n; /*put the current code in it*/ treepos = 0; } else @@ -611,17 +561,17 @@ static unsigned HuffmanTree_make2DTree(HuffmanTree* tree) (it's just nodefilled + 1)...*/ nodefilled++; /*addresses encoded with numcodes added to it*/ - tree->tree2d.data[2 * treepos + bit] = nodefilled + tree->numcodes; + tree->tree2d[2 * treepos + bit] = nodefilled + tree->numcodes; treepos = nodefilled; } } - else treepos = tree->tree2d.data[2 * treepos + bit] - tree->numcodes; + else treepos = tree->tree2d[2 * treepos + bit] - tree->numcodes; } } for(n = 0; n < tree->numcodes * 2; n++) { - if(tree->tree2d.data[n] == 32767) tree->tree2d.data[n] = 0; /*remove possible remaining 32767's*/ + if(tree->tree2d[n] == 32767) tree->tree2d[n] = 0; /*remove possible remaining 32767's*/ } return 0; @@ -640,15 +590,18 @@ static unsigned HuffmanTree_makeFromLengths2(HuffmanTree* tree) uivector_init(&blcount); uivector_init(&nextcode); - if(!uivector_resize(&tree->tree1d, tree->numcodes) - || !uivector_resizev(&blcount, tree->maxbitlen + 1, 0) + + tree->tree1d = (unsigned*)mymalloc(tree->numcodes * sizeof(unsigned)); + if(!tree->tree1d) error = 83; /*alloc fail*/ + + if(!uivector_resizev(&blcount, tree->maxbitlen + 1, 0) || !uivector_resizev(&nextcode, tree->maxbitlen + 1, 0)) - error = 9902; /*alloc fail*/ + error = 83; /*alloc fail*/ if(!error) { /*step 1: count number of instances of each code length*/ - for(bits = 0; bits < tree->numcodes; bits++) blcount.data[tree->lengths.data[bits]]++; + for(bits = 0; bits < tree->numcodes; bits++) blcount.data[tree->lengths[bits]]++; /*step 2: generate the nextcode values*/ for(bits = 1; bits <= tree->maxbitlen; bits++) { @@ -657,7 +610,7 @@ static unsigned HuffmanTree_makeFromLengths2(HuffmanTree* tree) /*step 3: generate all the codes*/ for(n = 0; n < tree->numcodes; n++) { - if(tree->lengths.data[n] != 0) tree->tree1d.data[n] = nextcode.data[tree->lengths.data[n]]++; + if(tree->lengths[n] != 0) tree->tree1d[n] = nextcode.data[tree->lengths[n]]++; } } @@ -677,8 +630,9 @@ static unsigned HuffmanTree_makeFromLengths(HuffmanTree* tree, const unsigned* b size_t numcodes, unsigned maxbitlen) { unsigned i; - if(!uivector_resize(&tree->lengths, numcodes)) return 9903; /*alloc fail*/ - for(i = 0; i < numcodes; i++) tree->lengths.data[i] = bitlen[i]; + tree->lengths = (unsigned*)mymalloc(numcodes * sizeof(unsigned)); + if(!tree->lengths) return 83; /*alloc fail*/ + for(i = 0; i < numcodes; i++) tree->lengths[i] = bitlen[i]; tree->numcodes = (unsigned)numcodes; /*number of symbols*/ tree->maxbitlen = maxbitlen; return HuffmanTree_makeFromLengths2(tree); @@ -697,35 +651,47 @@ typedef struct Coin float weight; /*the sum of all weights in this coin*/ } Coin; -static void Coin_init(Coin* c) +static void coin_init(Coin* c) { uivector_init(&c->symbols); } /*argument c is void* so that this dtor can be given as function pointer to the vector resize function*/ -static void Coin_cleanup(void* c) +static void coin_cleanup(void* c) { uivector_cleanup(&((Coin*)c)->symbols); } -static void Coin_copy(Coin* c1, const Coin* c2) +static void coin_copy(Coin* c1, const Coin* c2) { c1->weight = c2->weight; uivector_copy(&c1->symbols, &c2->symbols); } -static void addCoins(Coin* c1, const Coin* c2) +static void add_coins(Coin* c1, const Coin* c2) { size_t i; for(i = 0; i < c2->symbols.size; i++) uivector_push_back(&c1->symbols, c2->symbols.data[i]); c1->weight += c2->weight; } +static void init_coins(Coin* coins, size_t num) +{ + size_t i; + for(i = 0; i < num; i++) coin_init(&coins[i]); +} + +static void cleanup_coins(Coin* coins, size_t num) +{ + size_t i; + for(i = 0; i < num; i++) coin_cleanup(&coins[i]); +} + /* -Coin_sort: This uses a simple combsort to sort the data. This function is not critical for +This uses a simple combsort to sort the data. This function is not critical for overall encoding speed and the data amount isn't that large. */ -static void Coin_sort(Coin* data, size_t amount) +static void sort_coins(Coin* data, size_t amount) { size_t gap = amount; unsigned char swapped = 0; @@ -749,39 +715,34 @@ static void Coin_sort(Coin* data, size_t amount) } } -static unsigned HuffmanTree_fillInCoins(vector* coins, const unsigned* frequencies, unsigned numcodes, size_t sum) +static unsigned append_symbol_coins(Coin* coins, const unsigned* frequencies, unsigned numcodes, size_t sum) { unsigned i; + unsigned j = 0; /*index of present symbols*/ for(i = 0; i < numcodes; i++) { - Coin* coin; - if(frequencies[i] == 0) continue; /*it's important to exclude symbols that aren't present*/ - if(!vector_resize(coins, coins->size + 1)) + if(frequencies[i] != 0) /*only include symbols that are present*/ { - vector_cleanup(coins); - return 9904; /*alloc fail*/ + coins[j].weight = frequencies[i] / (float)sum; + uivector_push_back(&coins[j].symbols, i); + j++; } - coin = (Coin*)(vector_get(coins, coins->size - 1)); - Coin_init(coin); - coin->weight = frequencies[i] / (float)sum; - uivector_push_back(&coin->symbols, i); } - if(coins->size) Coin_sort((Coin*)coins->data, coins->size); return 0; } -/*Create the Huffman tree given the symbol frequencies*/ -static unsigned HuffmanTree_makeFromFrequencies(HuffmanTree* tree, const unsigned* frequencies, - size_t numcodes, unsigned maxbitlen) +unsigned lodepng_huffman_code_lengths(unsigned* lengths, const unsigned* frequencies, + size_t numcodes, unsigned maxbitlen) { unsigned i, j; size_t sum = 0, numpresent = 0; unsigned error = 0; + Coin* coins; /*the coins of the currently calculated row*/ + Coin* prev_row; /*the previous row of coins*/ + unsigned numcoins; + unsigned coinmem; - vector prev_row; /*type Coin, the previous row of coins*/ - vector coins; /*type Coin, the coins of the currently calculated row*/ - - tree->maxbitlen = maxbitlen; + if(numcodes == 0) return 80; /*error: a tree of 0 symbols is not supposed to be made*/ for(i = 0; i < numcodes; i++) { @@ -792,83 +753,124 @@ static unsigned HuffmanTree_makeFromFrequencies(HuffmanTree* tree, const unsigne } } - if(numcodes == 0) return 80; /*error: a tree of 0 symbols is not supposed to be made*/ - tree->numcodes = (unsigned)numcodes; /*number of symbols*/ - uivector_resize(&tree->lengths, 0); - if(!uivector_resizev(&tree->lengths, tree->numcodes, 0)) return 9905; /*alloc fail*/ + for(i = 0; i < numcodes; i++) lengths[i] = 0; - /*there are no symbols at all, in that case add one symbol of value 0 to the tree (see RFC 1951 section 3.2.7) */ + /*ensure at least two present symbols. There should be at least one symbol + according to RFC 1951 section 3.2.7. To decoders incorrectly require two. To + make these work as well ensure there are at least two symbols. The + Package-Merge code below also doesn't work correctly if there's only one + symbol, it'd give it the theoritical 0 bits but in practice zlib wants 1 bit*/ if(numpresent == 0) { - tree->lengths.data[0] = 1; - return HuffmanTree_makeFromLengths2(tree); + lengths[0] = lengths[1] = 1; /*note that for RFC 1951 section 3.2.7, only lengths[0] = 1 is needed*/ } - /*the package merge algorithm gives wrong results if there's only one symbol - (theoretically 0 bits would then suffice, but we need a proper symbol for zlib)*/ else if(numpresent == 1) { - for(i = 0; i < numcodes; i++) if(frequencies[i]) tree->lengths.data[i] = 1; - return HuffmanTree_makeFromLengths2(tree); - } - - vector_init(&coins, sizeof(Coin)); - vector_init(&prev_row, sizeof(Coin)); - - /*Package-Merge algorithm represented by coin collector's problem - For every symbol, maxbitlen coins will be created*/ - - /*first row, lowest denominator*/ - error = HuffmanTree_fillInCoins(&coins, frequencies, tree->numcodes, sum); - if(!error) - { - for(j = 1; j <= maxbitlen && !error; j++) /*each of the remaining rows*/ + for(i = 0; i < numcodes; i++) { - vector_swap(&coins, &prev_row); /*swap instead of copying*/ - if(!vector_resized(&coins, 0, Coin_cleanup)) ERROR_BREAK(9906 /*alloc fail*/); - for(i = 0; i + 1 < prev_row.size; i += 2) + if(frequencies[i]) { - if(!vector_resize(&coins, coins.size + 1)) ERROR_BREAK(9907 /*alloc fail*/); - Coin_init((Coin*)vector_get(&coins, coins.size - 1)); - Coin_copy((Coin*)vector_get(&coins, coins.size - 1), (Coin*)vector_get(&prev_row, i)); - /*merge the coins into packages*/ - addCoins((Coin*)vector_get(&coins, coins.size - 1), (Coin*)vector_get(&prev_row, i + 1)); - } - if(j < maxbitlen) - { - error = HuffmanTree_fillInCoins(&coins, frequencies, tree->numcodes, sum); + lengths[i] = 1; + lengths[i == 0 ? 1 : 0] = 1; + break; } } } - - if(!error) + else { - /*keep the coins with lowest weight, so that they add up to the amount of symbols - 1*/ - vector_resized(&coins, numpresent - 1, Coin_cleanup); + /*Package-Merge algorithm represented by coin collector's problem + For every symbol, maxbitlen coins will be created*/ - /*calculate the lenghts of each symbol, as the amount of times a coin of each symbol is used*/ - for(i = 0; i < coins.size; i++) + coinmem = numpresent * 2; /*max amount of coins needed with the current algo*/ + coins = (Coin*)mymalloc(sizeof(Coin) * coinmem); + prev_row = (Coin*)mymalloc(sizeof(Coin) * coinmem); + if(!coins || !prev_row) return 83; /*alloc fail*/ + init_coins(coins, coinmem); + init_coins(prev_row, coinmem); + + /*first row, lowest denominator*/ + error = append_symbol_coins(coins, frequencies, numcodes, sum); + numcoins = numpresent; + sort_coins(coins, numcoins); + if(!error) { - Coin* coin = (Coin*)vector_get(&coins, i); - for(j = 0; j < coin->symbols.size; j++) tree->lengths.data[coin->symbols.data[j]]++; + unsigned numprev = 0; + for(j = 1; j <= maxbitlen && !error; j++) /*each of the remaining rows*/ + { + unsigned tempnum; + Coin* tempcoins; + /*swap prev_row and coins, and their amounts*/ + tempcoins = prev_row; prev_row = coins; coins = tempcoins; + tempnum = numprev; numprev = numcoins; numcoins = tempnum; + + cleanup_coins(coins, numcoins); + init_coins(coins, numcoins); + + numcoins = 0; + + /*fill in the merged coins of the previous row*/ + for(i = 0; i + 1 < numprev; i += 2) + { + /*merge prev_row[i] and prev_row[i + 1] into new coin*/ + Coin* coin = &coins[numcoins++]; + coin_copy(coin, &prev_row[i]); + add_coins(coin, &prev_row[i + 1]); + } + /*fill in all the original symbols again*/ + if(j < maxbitlen) + { + error = append_symbol_coins(coins + numcoins, frequencies, numcodes, sum); + numcoins += numpresent; + } + sort_coins(coins, numcoins); + } } - error = HuffmanTree_makeFromLengths2(tree); + if(!error) + { + /*calculate the lenghts of each symbol, as the amount of times a coin of each symbol is used*/ + for(i = 0; i < numpresent - 1; i++) + { + Coin* coin = &coins[i]; + for(j = 0; j < coin->symbols.size; j++) lengths[coin->symbols.data[j]]++; + } + } + + cleanup_coins(coins, coinmem); + myfree(coins); + cleanup_coins(prev_row, coinmem); + myfree(prev_row); } - vector_cleanupd(&coins, Coin_cleanup); - vector_cleanupd(&prev_row, Coin_cleanup); + return error; +} +/*Create the Huffman tree given the symbol frequencies*/ +static unsigned HuffmanTree_makeFromFrequencies(HuffmanTree* tree, const unsigned* frequencies, + size_t mincodes, size_t numcodes, unsigned maxbitlen) +{ + unsigned error = 0; + while(!frequencies[numcodes - 1] && numcodes > mincodes) numcodes--; /*trim zeroes*/ + tree->maxbitlen = maxbitlen; + tree->numcodes = (unsigned)numcodes; /*number of symbols*/ + tree->lengths = (unsigned*)myrealloc(tree->lengths, numcodes * sizeof(unsigned)); + if(!tree->lengths) return 83; /*alloc fail*/ + /*initialize all lengths to 0*/ + memset(tree->lengths, 0, numcodes * sizeof(unsigned)); + + error = lodepng_huffman_code_lengths(tree->lengths, frequencies, numcodes, maxbitlen); + if(!error) error = HuffmanTree_makeFromLengths2(tree); return error; } static unsigned HuffmanTree_getCode(const HuffmanTree* tree, unsigned index) { - return tree->tree1d.data[index]; + return tree->tree1d[index]; } static unsigned HuffmanTree_getLength(const HuffmanTree* tree, unsigned index) { - return tree->lengths.data[index]; + return tree->lengths[index]; } #endif /*LODEPNG_COMPILE_ENCODER*/ @@ -876,22 +878,18 @@ static unsigned HuffmanTree_getLength(const HuffmanTree* tree, unsigned index) static unsigned generateFixedLitLenTree(HuffmanTree* tree) { unsigned i, error = 0; - uivector bitlen; - uivector_init(&bitlen); - if(!uivector_resize(&bitlen, NUM_DEFLATE_CODE_SYMBOLS)) error = 9909; /*alloc fail*/ + unsigned* bitlen = (unsigned*)mymalloc(NUM_DEFLATE_CODE_SYMBOLS * sizeof(unsigned)); + if(!bitlen) return 83; /*alloc fail*/ - if(!error) - { - /*288 possible codes: 0-255=literals, 256=endcode, 257-285=lengthcodes, 286-287=unused*/ - for(i = 0; i <= 143; i++) bitlen.data[i] = 8; - for(i = 144; i <= 255; i++) bitlen.data[i] = 9; - for(i = 256; i <= 279; i++) bitlen.data[i] = 7; - for(i = 280; i <= 287; i++) bitlen.data[i] = 8; + /*288 possible codes: 0-255=literals, 256=endcode, 257-285=lengthcodes, 286-287=unused*/ + for(i = 0; i <= 143; i++) bitlen[i] = 8; + for(i = 144; i <= 255; i++) bitlen[i] = 9; + for(i = 256; i <= 279; i++) bitlen[i] = 7; + for(i = 280; i <= 287; i++) bitlen[i] = 8; - error = HuffmanTree_makeFromLengths(tree, bitlen.data, NUM_DEFLATE_CODE_SYMBOLS, 15); - } + error = HuffmanTree_makeFromLengths(tree, bitlen, NUM_DEFLATE_CODE_SYMBOLS, 15); - uivector_cleanup(&bitlen); + myfree(bitlen); return error; } @@ -899,17 +897,14 @@ static unsigned generateFixedLitLenTree(HuffmanTree* tree) static unsigned generateFixedDistanceTree(HuffmanTree* tree) { unsigned i, error = 0; - uivector bitlen; - uivector_init(&bitlen); - if(!uivector_resize(&bitlen, NUM_DISTANCE_SYMBOLS)) error = 9910; /*alloc fail*/ + unsigned* bitlen = (unsigned*)mymalloc(NUM_DISTANCE_SYMBOLS * sizeof(unsigned)); + if(!bitlen) return 83; /*alloc fail*/ /*there are 32 distance codes, but 30-31 are unused*/ - if(!error) - { - for(i = 0; i < NUM_DISTANCE_SYMBOLS; i++) bitlen.data[i] = 5; - error = HuffmanTree_makeFromLengths(tree, bitlen.data, NUM_DISTANCE_SYMBOLS, 15); - } - uivector_cleanup(&bitlen); + for(i = 0; i < NUM_DISTANCE_SYMBOLS; i++) bitlen[i] = 5; + error = HuffmanTree_makeFromLengths(tree, bitlen, NUM_DISTANCE_SYMBOLS, 15); + + myfree(bitlen); return error; } @@ -925,13 +920,12 @@ static unsigned huffmanDecodeSymbol(const unsigned char* in, size_t* bp, unsigned treepos = 0, ct; for(;;) { - if(*bp > inbitlength) return (unsigned)(-1); /*error: end of input memory reached without endcode*/ - + if(*bp >= inbitlength) return (unsigned)(-1); /*error: end of input memory reached without endcode*/ /* decode the symbol from the tree. The "readBitFromStream" code is inlined in the expression below because this is the biggest bottleneck while decoding */ - ct = codetree->tree2d.data[(treepos << 1) + READBIT(*bp, in)]; + ct = codetree->tree2d[(treepos << 1) + READBIT(*bp, in)]; (*bp)++; if(ct < codetree->numcodes) return ct; /*the symbol is decoded, return it*/ else treepos = ct - codetree->numcodes; /*symbol not yet decoded, instead move tree position*/ @@ -950,8 +944,7 @@ static unsigned huffmanDecodeSymbol(const unsigned char* in, size_t* bp, /*get the tree of a deflated block with fixed tree, as specified in the deflate specification*/ static void getTreeInflateFixed(HuffmanTree* tree_ll, HuffmanTree* tree_d) { - /*error checking not done, this is fixed stuff, it works, it doesn't depend on the image*/ - /*TODO: out of memory errors could still happen...*/ + /*TODO: check for out of memory errors*/ generateFixedLitLenTree(tree_ll); generateFixedDistanceTree(tree_d); } @@ -966,13 +959,13 @@ static unsigned getTreeInflateDynamic(HuffmanTree* tree_ll, HuffmanTree* tree_d, size_t inbitlength = inlength * 8; /*see comments in deflateDynamic for explanation of the context and these variables, it is analogous*/ - uivector bitlen_ll; /*lit,len code lengths*/ - uivector bitlen_d; /*dist code lengths*/ + unsigned* bitlen_ll = 0; /*lit,len code lengths*/ + unsigned* bitlen_d = 0; /*dist code lengths*/ /*code length code lengths ("clcl"), the bit lengths of the huffman tree used to compress bitlen_ll and bitlen_d*/ - uivector bitlen_cl; + unsigned* bitlen_cl = 0; HuffmanTree tree_cl; /*the code tree for code length codes (the huffman tree for compressed huffman trees)*/ - if((*bp) >> 3 >= inlength - 2) return 49; /*the bit pointer is or will go past the memory*/ + if((*bp) >> 3 >= inlength - 2) return 49; /*error: the bit pointer is or will go past the memory*/ /*number of literal/length codes + 257. Unlike the spec, the value 257 is added to it here already*/ HLIT = readBitsFromStream(bp, in, 5) + 257; @@ -982,39 +975,39 @@ static unsigned getTreeInflateDynamic(HuffmanTree* tree_ll, HuffmanTree* tree_d, HCLEN = readBitsFromStream(bp, in, 4) + 4; HuffmanTree_init(&tree_cl); - uivector_init(&bitlen_ll); - uivector_init(&bitlen_d); - uivector_init(&bitlen_cl); while(!error) { /*read the code length codes out of 3 * (amount of code length codes) bits*/ - - if(!uivector_resize(&bitlen_cl, NUM_CODE_LENGTH_CODES)) ERROR_BREAK(9911); + + bitlen_cl = (unsigned*)mymalloc(NUM_CODE_LENGTH_CODES * sizeof(unsigned)); + if(!bitlen_cl) ERROR_BREAK(83 /*alloc fail*/); for(i = 0; i < NUM_CODE_LENGTH_CODES; i++) { - if(i < HCLEN) bitlen_cl.data[CLCL_ORDER[i]] = readBitsFromStream(bp, in, 3); - else bitlen_cl.data[CLCL_ORDER[i]] = 0; /*if not, it must stay 0*/ + if(i < HCLEN) bitlen_cl[CLCL_ORDER[i]] = readBitsFromStream(bp, in, 3); + else bitlen_cl[CLCL_ORDER[i]] = 0; /*if not, it must stay 0*/ } - error = HuffmanTree_makeFromLengths(&tree_cl, bitlen_cl.data, bitlen_cl.size, 7); + error = HuffmanTree_makeFromLengths(&tree_cl, bitlen_cl, NUM_CODE_LENGTH_CODES, 7); if(error) break; /*now we can use this tree to read the lengths for the tree that this function will return*/ - uivector_resizev(&bitlen_ll, NUM_DEFLATE_CODE_SYMBOLS, 0); - uivector_resizev(&bitlen_d, NUM_DISTANCE_SYMBOLS, 0); - i = 0; - if(!bitlen_ll.data || !bitlen_d.data) ERROR_BREAK(9912); /*alloc fail*/ + bitlen_ll = (unsigned*)mymalloc(NUM_DEFLATE_CODE_SYMBOLS * sizeof(unsigned)); + bitlen_d = (unsigned*)mymalloc(NUM_DISTANCE_SYMBOLS * sizeof(unsigned)); + if(!bitlen_ll || !bitlen_d) ERROR_BREAK(83 /*alloc fail*/); + for(i = 0; i < NUM_DEFLATE_CODE_SYMBOLS; i++) bitlen_ll[i] = 0; + for(i = 0; i < NUM_DISTANCE_SYMBOLS; i++) bitlen_d[i] = 0; /*i is the current symbol we're reading in the part that contains the code lengths of lit/len and dist codes*/ + i = 0; while(i < HLIT + HDIST) { unsigned code = huffmanDecodeSymbol(in, bp, &tree_cl, inbitlength); if(code <= 15) /*a length code*/ { - if(i < HLIT) bitlen_ll.data[i] = code; - else bitlen_d.data[i - HLIT] = code; + if(i < HLIT) bitlen_ll[i] = code; + else bitlen_d[i - HLIT] = code; i++; } else if(code == 16) /*repeat previous*/ @@ -1022,25 +1015,26 @@ static unsigned getTreeInflateDynamic(HuffmanTree* tree_ll, HuffmanTree* tree_d, unsigned replength = 3; /*read in the 2 bits that indicate repeat length (3-6)*/ unsigned value; /*set value to the previous code*/ - if((*bp) >> 3 >= inlength) ERROR_BREAK(50); /*error, bit pointer jumps past memory*/ + if(*bp >= inbitlength) ERROR_BREAK(50); /*error, bit pointer jumps past memory*/ + if (i == 0) ERROR_BREAK(54); /*can't repeat previous if i is 0*/ replength += readBitsFromStream(bp, in, 2); - if((i - 1) < HLIT) value = bitlen_ll.data[i - 1]; - else value = bitlen_d.data[i - HLIT - 1]; + if(i < HLIT + 1) value = bitlen_ll[i - 1]; + else value = bitlen_d[i - HLIT - 1]; /*repeat this value in the next lengths*/ for(n = 0; n < replength; n++) { if(i >= HLIT + HDIST) ERROR_BREAK(13); /*error: i is larger than the amount of codes*/ - if(i < HLIT) bitlen_ll.data[i] = value; - else bitlen_d.data[i - HLIT] = value; + if(i < HLIT) bitlen_ll[i] = value; + else bitlen_d[i - HLIT] = value; i++; } } else if(code == 17) /*repeat "0" 3-10 times*/ { unsigned replength = 3; /*read in the bits that indicate repeat length*/ - if((*bp) >> 3 >= inlength) ERROR_BREAK(50); /*error, bit pointer jumps past memory*/ + if(*bp >= inbitlength) ERROR_BREAK(50); /*error, bit pointer jumps past memory*/ replength += readBitsFromStream(bp, in, 3); @@ -1049,15 +1043,15 @@ static unsigned getTreeInflateDynamic(HuffmanTree* tree_ll, HuffmanTree* tree_d, { if(i >= HLIT + HDIST) ERROR_BREAK(14); /*error: i is larger than the amount of codes*/ - if(i < HLIT) bitlen_ll.data[i] = 0; - else bitlen_d.data[i - HLIT] = 0; + if(i < HLIT) bitlen_ll[i] = 0; + else bitlen_d[i - HLIT] = 0; i++; } } else if(code == 18) /*repeat "0" 11-138 times*/ { unsigned replength = 11; /*read in the bits that indicate repeat length*/ - if((*bp) >> 3 >= inlength) ERROR_BREAK(50); /*error, bit pointer jumps past memory*/ + if(*bp >= inbitlength) ERROR_BREAK(50); /*error, bit pointer jumps past memory*/ replength += readBitsFromStream(bp, in, 7); @@ -1066,8 +1060,8 @@ static unsigned getTreeInflateDynamic(HuffmanTree* tree_ll, HuffmanTree* tree_d, { if(i >= HLIT + HDIST) ERROR_BREAK(15); /*error: i is larger than the amount of codes*/ - if(i < HLIT) bitlen_ll.data[i] = 0; - else bitlen_d.data[i - HLIT] = 0; + if(i < HLIT) bitlen_ll[i] = 0; + else bitlen_d[i - HLIT] = 0; i++; } } @@ -1077,7 +1071,7 @@ static unsigned getTreeInflateDynamic(HuffmanTree* tree_ll, HuffmanTree* tree_d, { /*return error code 10 or 11 depending on the situation that happened in huffmanDecodeSymbol (10=no endcode, 11=wrong jump outside of tree)*/ - error = (*bp) > inlength * 8 ? 10 : 11; + error = (*bp) > inbitlength ? 10 : 11; } else error = 16; /*unexisting code, this can never happen*/ break; @@ -1085,19 +1079,19 @@ static unsigned getTreeInflateDynamic(HuffmanTree* tree_ll, HuffmanTree* tree_d, } if(error) break; - if(bitlen_ll.data[256] == 0) ERROR_BREAK(64); /*the length of the end code 256 must be larger than 0*/ + if(bitlen_ll[256] == 0) ERROR_BREAK(64); /*the length of the end code 256 must be larger than 0*/ /*now we've finally got HLIT and HDIST, so generate the code trees, and the function is done*/ - error = HuffmanTree_makeFromLengths(tree_ll, &bitlen_ll.data[0], bitlen_ll.size, 15); + error = HuffmanTree_makeFromLengths(tree_ll, bitlen_ll, NUM_DEFLATE_CODE_SYMBOLS, 15); if(error) break; - error = HuffmanTree_makeFromLengths(tree_d, &bitlen_d.data[0], bitlen_d.size, 15); + error = HuffmanTree_makeFromLengths(tree_d, bitlen_d, NUM_DISTANCE_SYMBOLS, 15); break; /*end of error-while*/ } - uivector_cleanup(&bitlen_cl); - uivector_cleanup(&bitlen_ll); - uivector_cleanup(&bitlen_d); + myfree(bitlen_cl); + myfree(bitlen_ll); + myfree(bitlen_d); HuffmanTree_cleanup(&tree_cl); return error; @@ -1116,12 +1110,9 @@ static unsigned inflateHuffmanBlock(ucvector* out, const unsigned char* in, size HuffmanTree_init(&tree_d); if(btype == 1) getTreeInflateFixed(&tree_ll, &tree_d); - else if(btype == 2) - { - error = getTreeInflateDynamic(&tree_ll, &tree_d, in, bp, inlength); - } + else if(btype == 2) error = getTreeInflateDynamic(&tree_ll, &tree_d, in, bp, inlength); - for(;;) /*decode all symbols until end reached*/ + while(!error) /*decode all symbols until end reached, breaks at end code*/ { /*code_ll is literal, length or end code*/ unsigned code_ll = huffmanDecodeSymbol(in, bp, &tree_ll, inbitlength); @@ -1130,7 +1121,7 @@ static unsigned inflateHuffmanBlock(ucvector* out, const unsigned char* in, size if((*pos) >= out->size) { /*reserve more room at once*/ - if(!ucvector_resize(out, ((*pos) + 1) * 2)) ERROR_BREAK(9913 /*alloc fail*/); + if(!ucvector_resize(out, ((*pos) + 1) * 2)) ERROR_BREAK(83 /*alloc fail*/); } out->data[(*pos)] = (unsigned char)(code_ll); (*pos)++; @@ -1140,13 +1131,13 @@ static unsigned inflateHuffmanBlock(ucvector* out, const unsigned char* in, size unsigned code_d, distance; unsigned numextrabits_l, numextrabits_d; /*extra bits for length and distance*/ size_t start, forward, backward, length; - + /*part 1: get length base*/ length = LENGTHBASE[code_ll - FIRST_LENGTH_CODE_INDEX]; /*part 2: get extra bits and add the value of that to length*/ numextrabits_l = LENGTHEXTRA[code_ll - FIRST_LENGTH_CODE_INDEX]; - if(((*bp) >> 3) >= inlength) ERROR_BREAK(51); /*error, bit pointer will jump past memory*/ + if(*bp >= inbitlength) ERROR_BREAK(51); /*error, bit pointer will jump past memory*/ length += readBitsFromStream(bp, in, numextrabits_l); /*part 3: get distance code*/ @@ -1166,17 +1157,18 @@ static unsigned inflateHuffmanBlock(ucvector* out, const unsigned char* in, size /*part 4: get extra bits from distance*/ numextrabits_d = DISTANCEEXTRA[code_d]; - if(((*bp) >> 3) >= inlength) ERROR_BREAK(51); /*error, bit pointer will jump past memory*/ + if(*bp >= inbitlength) ERROR_BREAK(51); /*error, bit pointer will jump past memory*/ distance += readBitsFromStream(bp, in, numextrabits_d); /*part 5: fill in all the out[n] values based on the length and dist*/ start = (*pos); + if(distance > start) ERROR_BREAK(52); /*too long backward distance*/ backward = start - distance; if((*pos) + length >= out->size) { /*reserve more room at once*/ - if(!ucvector_resize(out, ((*pos) + length) * 2)) ERROR_BREAK(9914 /*alloc fail*/); + if(!ucvector_resize(out, ((*pos) + length) * 2)) ERROR_BREAK(83 /*alloc fail*/); } for(forward = 0; forward < length; forward++) @@ -1224,7 +1216,7 @@ static unsigned inflateNoCompression(ucvector* out, const unsigned char* in, siz if((*pos) + LEN >= out->size) { - if(!ucvector_resize(out, (*pos) + LEN)) return 9915; /*alloc fail*/ + if(!ucvector_resize(out, (*pos) + LEN)) return 83; /*alloc fail*/ } /*read the literal data: LEN bytes are now stored in the out buffer*/ @@ -1236,8 +1228,9 @@ static unsigned inflateNoCompression(ucvector* out, const unsigned char* in, siz return error; } -/*inflate the deflated data (cfr. deflate spec); return value is the error*/ -static unsigned LodePNG_inflate(ucvector* out, const unsigned char* in, size_t insize, size_t inpos) +static unsigned lodepng_inflatev(ucvector* out, + const unsigned char* in, size_t insize, + const LodePNGDecompressSettings* settings) { /*bit pointer in the "in" data, current byte is bp >> 3, current bit is bp & 0x7 (from lsb to msb of the byte)*/ size_t bp = 0; @@ -1246,27 +1239,56 @@ static unsigned LodePNG_inflate(ucvector* out, const unsigned char* in, size_t i unsigned error = 0; + (void)settings; + while(!BFINAL) { unsigned BTYPE; if(bp + 2 >= insize * 8) return 52; /*error, bit pointer will jump past memory*/ - BFINAL = readBitFromStream(&bp, &in[inpos]); - BTYPE = 1 * readBitFromStream(&bp, &in[inpos]); - BTYPE += 2 * readBitFromStream(&bp, &in[inpos]); + BFINAL = readBitFromStream(&bp, in); + BTYPE = 1 * readBitFromStream(&bp, in); + BTYPE += 2 * readBitFromStream(&bp, in); if(BTYPE == 3) return 20; /*error: invalid BTYPE*/ - else if(BTYPE == 0) error = inflateNoCompression(out, &in[inpos], &bp, &pos, insize); /*no compression*/ - else error = inflateHuffmanBlock(out, &in[inpos], &bp, &pos, insize, BTYPE); /*compression, BTYPE 01 or 10*/ + else if(BTYPE == 0) error = inflateNoCompression(out, in, &bp, &pos, insize); /*no compression*/ + else error = inflateHuffmanBlock(out, in, &bp, &pos, insize, BTYPE); /*compression, BTYPE 01 or 10*/ if(error) return error; } - + /*Only now we know the true size of out, resize it to that*/ - if(!ucvector_resize(out, pos)) error = 9916; /*alloc fail*/ + if(!ucvector_resize(out, pos)) error = 83; /*alloc fail*/ return error; } +unsigned lodepng_inflate(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGDecompressSettings* settings) +{ + unsigned error; + ucvector v; + ucvector_init_buffer(&v, *out, *outsize); + error = lodepng_inflatev(&v, in, insize, settings); + *out = v.data; + *outsize = v.size; + return error; +} + +static unsigned inflate(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGDecompressSettings* settings) +{ + if(settings->custom_inflate) + { + return settings->custom_inflate(out, outsize, in, insize, settings); + } + else + { + return lodepng_inflate(out, outsize, in, insize, settings); + } +} + #endif /*LODEPNG_COMPILE_DECODER*/ #ifdef LODEPNG_COMPILE_ENCODER @@ -1323,65 +1345,7 @@ static void addLengthDistance(uivector* values, size_t length, size_t distance) uivector_push_back(values, extra_distance); } -#if 0 -/*the "brute force" version of the encodeLZ7 algorithm, not used anymore, kept here for reference*/ -static unsigned encodeLZ77_brute(uivector* out, const unsigned char* in, size_t insize, unsigned windowSize) -{ - size_t pos; - for(pos = 0; pos < insize; pos++) - { - size_t length = 0, offset = 0; /*the length and offset found for the current position*/ - size_t max_offset = pos < windowSize ? pos : windowSize; /*how far back to test*/ - size_t current_offset; - - /**search for the longest string, backwards through all possible distances (=offsets)**/ - for(current_offset = 1; current_offset < max_offset; current_offset++) - { - size_t backpos = pos - current_offset; - if(in[backpos] == in[pos]) - { - /*test the next characters*/ - size_t current_length = 1; - size_t backtest = backpos + 1; - size_t foretest = pos + 1; - /*maximum supporte length by deflate is max length*/ - while(foretest < insize && in[backtest] == in[foretest] && current_length < MAX_SUPPORTED_DEFLATE_LENGTH) - { - if(backpos >= pos) - { - /*continue as if we work on the decoded bytes after pos by jumping back before pos*/ - backpos -= current_offset; - } - current_length++; - backtest++; - foretest++; - } - if(current_length > length) - { - length = current_length; /*the longest length*/ - offset = current_offset; /*the offset that is related to this longest length*/ - /*you can jump out of this for loop once a length of max length is found (gives significant speed gain)*/ - if(current_length == MAX_SUPPORTED_DEFLATE_LENGTH) break; - } - } - } - - /**encode it as length/distance pair or literal value**/ - if(length < 3) /*only lengths of 3 or higher are supported as length/distance pair*/ - { - uivector_push_back(out, in[pos]); - } - else - { - addLengthDistance(out, length, offset); - pos += (length - 1); - } - } /*end of the loop through each character of input*/ - return 0; -} -#endif - -static const unsigned HASH_NUM_VALUES = 2048; +static const unsigned HASH_NUM_VALUES = 65536; static const unsigned HASH_NUM_CHARACTERS = 3; static const unsigned HASH_SHIFT = 2; /* @@ -1398,260 +1362,233 @@ combinations of bytes can give, the higher it is the more memory is needed, but if it's too low the advantage of hashing is gone. */ -static unsigned getHash(const unsigned char* data, size_t size, size_t pos, size_t num) +typedef struct Hash +{ + int* head; /*hash value to head circular pos*/ + int* val; /*circular pos to hash value*/ + /*circular pos to prev circular pos*/ + unsigned short* chain; + unsigned short* zeros; +} Hash; + +static unsigned hash_init(Hash* hash, unsigned windowsize) +{ + unsigned i; + hash->head = (int*)mymalloc(sizeof(int) * HASH_NUM_VALUES); + hash->val = (int*)mymalloc(sizeof(int) * windowsize); + hash->chain = (unsigned short*)mymalloc(sizeof(unsigned short) * windowsize); + hash->zeros = (unsigned short*)mymalloc(sizeof(unsigned short) * windowsize); + + if(!hash->head || !hash->val || !hash->chain || !hash->zeros) return 83; /*alloc fail*/ + + /*initialize hash table*/ + for(i = 0; i < HASH_NUM_VALUES; i++) hash->head[i] = -1; + for(i = 0; i < windowsize; i++) hash->val[i] = -1; + for(i = 0; i < windowsize; i++) hash->chain[i] = i; /*same value as index indicates uninitialized*/ + + return 0; +} + +static void hash_cleanup(Hash* hash) +{ + myfree(hash->head); + myfree(hash->val); + myfree(hash->chain); + myfree(hash->zeros); +} + +static unsigned getHash(const unsigned char* data, size_t size, size_t pos) { unsigned result = 0; size_t amount, i; if(pos >= size) return 0; - amount = num; + amount = HASH_NUM_CHARACTERS; if(pos + amount >= size) amount = size - pos; for(i = 0; i < amount; i++) result ^= (data[pos + i] << (i * HASH_SHIFT)); return result % HASH_NUM_VALUES; } -static unsigned countInitialZeros(const unsigned char* data, size_t size, size_t pos) +static unsigned countZeros(const unsigned char* data, size_t size, size_t pos) { - size_t max_count = MAX_SUPPORTED_DEFLATE_LENGTH; - size_t i; - if(max_count > size - pos) max_count = size - pos; - for(i = 0; i < max_count; i++) - { - if(data[pos + i] != 0) - return i; - } - return max_count; + const unsigned char* start = data + pos; + const unsigned char* end = start + MAX_SUPPORTED_DEFLATE_LENGTH; + if(end > data + size) end = data + size; + data = start; + while (data != end && *data == 0) data++; + /*subtracting two addresses returned as 32-bit number (max value is MAX_SUPPORTED_DEFLATE_LENGTH)*/ + return (unsigned)(data - start); } -/*push a value to the vector in a circular way. This is to do as if we're extending -the vector's size forever, but instead the size is limited to maxsize and it wraps -around, to avoid too large memory size. The pos pointer gets updated to the current -end (unless updatepos is false, in that case pos is only used to know the current -value). returns 1 on success, 0 if fail*/ -static unsigned push_circular(uivector* v, unsigned* pos, unsigned value, size_t maxsize, unsigned updatepos) +static void updateHashChain(Hash* hash, size_t pos, int hashval, unsigned windowsize) { - if(v->size < maxsize) - { - if(!uivector_push_back(v, value)) return 0; - if(updatepos) (*pos)++; - } - else - { - if(updatepos) - { - (*pos)++; - if((*pos) > maxsize) (*pos) = 1; - } - v->data[(*pos) - 1] = value; - } - return 1; + unsigned wpos = pos % windowsize; + hash->val[wpos] = hashval; + if(hash->head[hashval] != -1) hash->chain[wpos] = hash->head[hashval]; + hash->head[hashval] = wpos; } -/*Enable to use lazy instead of greedy matghing. It looks one byte further -to see if that one gives a longer distance. This gives slightly better compression, at the cost -of a speed loss.*/ -#define LAZY_MATCHING - /* LZ77-encode the data. Return value is error code. The input are raw bytes, the output is in the form of unsigned integers with codes representing for example literal bytes, or length/distance pairs. It uses a hash table technique to let it encode faster. When doing LZ77 encoding, a -sliding window (of windowSize) is used, and all past bytes in that window can be used as +sliding window (of windowsize) is used, and all past bytes in that window can be used as the "dictionary". A brute force search through all possible distances would be slow, and this hash technique is one out of several ways to speed this up. */ -static unsigned encodeLZ77(uivector* out, const unsigned char* in, size_t insize, unsigned windowSize) +static unsigned encodeLZ77(uivector* out, Hash* hash, + const unsigned char* in, size_t inpos, size_t insize, unsigned windowsize, + unsigned minmatch, unsigned nicematch, unsigned lazymatching) { - /**generate hash table**/ - /* - The hash table is 2-dimensional. For every possible hash value, it contains a list of positions - in the data where this hash occured. - tablepos1 and tablepos2 remember the last used start and end index in the hash table for each hash value. - */ - vector table; /*HASH_NUM_VALUES uivectors; this is what would be an std::vector > in C++*/ - uivector tablepos1, tablepos2; - /*hash 0 indicates a possible common case of a long sequence of zeros, store and use the amount here for a speedup*/ - uivector initialZerosTable; + unsigned short numzeros = 0; + int usezeros = windowsize >= 8192; /*for small window size, the 'max chain length' optimization does a better job*/ unsigned pos, i, error = 0; - unsigned hash_num_characters = HASH_NUM_CHARACTERS; - - vector_init(&table, sizeof(uivector)); - if(!vector_resize(&table, HASH_NUM_VALUES)) return 9917; /*alloc fail*/ - for(i = 0; i < HASH_NUM_VALUES; i++) - { - uivector* v = (uivector*)vector_get(&table, i); - uivector_init(v); - } - - /*remember start and end positions in the tables to search in*/ - uivector_init(&tablepos1); - uivector_init(&tablepos2); - uivector_init(&initialZerosTable); - - if(!uivector_resizev(&tablepos1, HASH_NUM_VALUES, 0)) error = 9918; /*alloc fail*/ - if(!uivector_resizev(&tablepos2, HASH_NUM_VALUES, 0)) error = 9919; /*alloc fail*/ + /*for large window lengths, assume the user wants no compression loss. Otherwise, max hash chain length speedup.*/ + unsigned maxchainlength = windowsize >= 8192 ? windowsize : windowsize / 8; + unsigned maxlazymatch = windowsize >= 8192 ? MAX_SUPPORTED_DEFLATE_LENGTH : 64; if(!error) { - unsigned offset, max_offset; /*the offset represents the distance in LZ77 terminology*/ - unsigned length, tablepos; -#ifdef LAZY_MATCHING + unsigned offset; /*the offset represents the distance in LZ77 terminology*/ + unsigned length; unsigned lazy = 0; unsigned lazylength = 0, lazyoffset = 0; -#endif /*LAZY_MATCHING*/ - unsigned hash, initialZeros = 0; - unsigned backpos, current_offset, t1, t2, t11, current_length; + unsigned hashval; + unsigned current_offset, current_length; const unsigned char *lastptr, *foreptr, *backptr; - uivector* v; /*vector from the hash table we're currently working on*/ - unsigned hashWindow = windowSize; - unsigned numones = 0; + unsigned short hashpos, prevpos; - for(pos = 0; pos < insize; pos++) + for(pos = inpos; pos < insize; pos++) { - length = 0, offset = 0; /*the length and offset found for the current position*/ - max_offset = pos < windowSize ? pos : windowSize; /*how far back to test*/ + size_t wpos = pos % windowsize; /*position for in 'circular' hash buffers*/ - /*search for the longest string. First find out where in the table to start - (the first value that is in the range from "pos - max_offset" to "pos")*/ - hash = getHash(in, insize, pos, hash_num_characters); - v = (uivector*)vector_get(&table, hash); - if(!push_circular(v, &tablepos2.data[hash], pos, hashWindow, 1)) ERROR_BREAK(9920 /*alloc fail*/); - - if(hash == 0) + hashval = getHash(in, insize, pos); + updateHashChain(hash, pos, hashval, windowsize); + + if(usezeros && hashval == 0) { - initialZeros = countInitialZeros(in, insize, pos); - if(!push_circular(&initialZerosTable, &tablepos2.data[hash], initialZeros, hashWindow, 0)) - ERROR_BREAK(9920 /*alloc fail*/); - } - - while(v->data[tablepos1.data[hash]] < pos - max_offset) - { - /*it now points to the first value in the table for which the index is - larger than or equal to pos - max_offset*/ - tablepos1.data[hash]++; - if(tablepos1.data[hash] >= hashWindow) tablepos1.data[hash] = 0; + numzeros = countZeros(in, insize, pos); + hash->zeros[wpos] = numzeros; } - t1 = tablepos1.data[hash]; - t2 = tablepos2.data[hash] - 1; - if(tablepos2.data[hash] == 0) t2 = hashWindow - 1; + /*the length and offset found for the current position*/ + length = 0; + offset = 0; + + prevpos = hash->head[hashval]; + hashpos = hash->chain[prevpos]; lastptr = &in[insize < pos + MAX_SUPPORTED_DEFLATE_LENGTH ? insize : pos + MAX_SUPPORTED_DEFLATE_LENGTH]; - t11 = t1 == 0 ? hashWindow - 1 : t1 - 1; - for(tablepos = t2 == 0 ? hashWindow - 1 : t2 - 1; - tablepos != t2 && tablepos != t11 && tablepos < v->size; - tablepos = tablepos == 0 ? hashWindow - 1 : tablepos - 1) + /*search for the longest string*/ + if(hash->val[wpos] == (int)hashval) { - backpos = v->data[tablepos]; - current_offset = pos - backpos; - /*test the next characters*/ - foreptr = &in[pos]; - backptr = &in[backpos]; + unsigned chainlength = 0; + for(;;) + { + /*stop when went completely around the circular buffer*/ + if(prevpos < wpos && hashpos > prevpos && hashpos <= wpos) break; + if(prevpos > wpos && (hashpos <= wpos || hashpos > prevpos)) break; + if(chainlength++ >= maxchainlength) break; - if(hash == 0) - { - unsigned skip = initialZerosTable.data[tablepos]; - if(skip > initialZeros) skip = initialZeros; - if(skip > insize - pos) skip = insize - pos; - backptr += skip; - foreptr += skip; - } - while(foreptr != lastptr && *backptr == *foreptr) /*maximum supported length by deflate is max length*/ - { - ++backptr; - ++foreptr; - } - current_length = (unsigned)(foreptr - &in[pos]); - if(current_length > length) - { - length = current_length; /*the longest length*/ - offset = current_offset; /*the offset that is related to this longest length*/ - /*you can jump out of this for loop once a length of max length is found (gives significant speed gain)*/ - if(current_length == MAX_SUPPORTED_DEFLATE_LENGTH) break; + current_offset = hashpos <= wpos ? wpos - hashpos : wpos - hashpos + windowsize; + if(current_offset > 0) + { + /*test the next characters*/ + foreptr = &in[pos]; + backptr = &in[pos - current_offset]; + + /*common case in PNGs is lots of zeros. Quickly skip over them as a speedup*/ + if(usezeros && hashval == 0 && hash->val[hashpos] == 0 /*hashval[hashpos] may be out of date*/) + { + unsigned short skip = hash->zeros[hashpos]; + if(skip > numzeros) skip = numzeros; + backptr += skip; + foreptr += skip; + } + + /* multiple checks at once per array bounds check */ + while(foreptr != lastptr && *backptr == *foreptr) /*maximum supported length by deflate is max length*/ + { + ++backptr; + ++foreptr; + } + current_length = (unsigned)(foreptr - &in[pos]); + + if(current_length > length) + { + length = current_length; /*the longest length*/ + offset = current_offset; /*the offset that is related to this longest length*/ + /*jump out once a length of max length is found (speed gain)*/ + if(current_length >= nicematch || current_length == MAX_SUPPORTED_DEFLATE_LENGTH) break; + } + } + + if(hashpos == hash->chain[hashpos]) break; + + prevpos = hashpos; + hashpos = hash->chain[hashpos]; } } -#ifdef LAZY_MATCHING - if(!lazy && length >= 3 && length < MAX_SUPPORTED_DEFLATE_LENGTH) + if(lazymatching) { - lazylength = length; - lazyoffset = offset; - lazy = 1; - continue; - } - if(lazy) - { - if(pos == 0) ERROR_BREAK(81); - lazy = 0; - if(length > lazylength + 1) + if(!lazy && length >= 3 && length <= maxlazymatch && length < MAX_SUPPORTED_DEFLATE_LENGTH) { - /*push the previous character as literal*/ - if(!uivector_push_back(out, in[pos - 1])) ERROR_BREAK(9921 /*alloc fail*/); + lazy = 1; + lazylength = length; + lazyoffset = offset; + continue; /*try the next byte*/ } - else + if(lazy) { - length = lazylength; - offset = lazyoffset; - pos--; + lazy = 0; + if(pos == 0) ERROR_BREAK(81); + if(length > lazylength + 1) + { + /*push the previous character as literal*/ + if(!uivector_push_back(out, in[pos - 1])) ERROR_BREAK(83 /*alloc fail*/); + } + else + { + length = lazylength; + offset = lazyoffset; + hash->head[hashval] = -1; /*the same hashchain update will be done, this ensures no wrong alteration*/ + pos--; + } } } -#endif /*LAZY_MATCHING*/ - + if(length >= 3 && offset > windowsize) ERROR_BREAK(86 /*too big (or overflown negative) offset*/); + /**encode it as length/distance pair or literal value**/ if(length < 3) /*only lengths of 3 or higher are supported as length/distance pair*/ { - if(!uivector_push_back(out, in[pos])) ERROR_BREAK(9921 /*alloc fail*/); + if(!uivector_push_back(out, in[pos])) ERROR_BREAK(83 /*alloc fail*/); + } + else if(length < minmatch || (length == 3 && offset > 4096)) + { + /*compensate for the fact that longer offsets have more extra bits, a + length of only 3 may be not worth it then*/ + if(!uivector_push_back(out, in[pos])) ERROR_BREAK(83 /*alloc fail*/); } else { - unsigned j, local_hash; addLengthDistance(out, length, offset); - for(j = 0; j < length - 1; j++) + for(i = 1; i < length; i++) { - unsigned* t2p; /*pointer to current tablepos2 element*/ pos++; - local_hash = getHash(in, insize, pos, hash_num_characters); - t2p = &tablepos2.data[local_hash]; - v = (uivector*)vector_get(&table, local_hash); - if(!push_circular(v, t2p, pos, hashWindow, 1)) ERROR_BREAK(9920 /*alloc fail*/); - - if(local_hash == 0) + hashval = getHash(in, insize, pos); + updateHashChain(hash, pos, hashval, windowsize); + if(usezeros && hashval == 0) { - initialZeros = countInitialZeros(in, insize, pos); - if(!push_circular(&initialZerosTable, t2p, initialZeros, hashWindow, 0)) - ERROR_BREAK(9922 /*alloc fail*/); - } - if(local_hash == 1 && hash_num_characters == 3) - { - /* - If many hash values are getting grouped together in hash value 1, 4, 16, 20, ..., - it indicates there are many near-zero values. This is not zero enough to benefit from a speed - increase from the initialZerosTable, and makes it very slow. For that case only, switch to - hash_num_characters = 6. Value 6 is experimentally found to be fastest. For this particular type - of file, the compression isn't even worse, despite the fact that lengths < 6 are now no longer - found, and that by changing hash_num_characters not all previously found hash values are still valid. - Almost all images compress fast enough and smaller with hash_num_characters = 3, except sine plasma - images. Those benefit a lot from this heuristic. - */ - if(numones > 8192 && numones > pos / 16) hash_num_characters = 6; - else numones++; + hash->zeros[pos % windowsize] = countZeros(in, insize, pos); } } } + } /*end of the loop through each character of input*/ } /*end of "if(!error)"*/ - /*cleanup*/ - for(i = 0; i < table.size; i++) - { - uivector* v = (uivector*)vector_get(&table, i); - uivector_cleanup(v); - } - vector_cleanup(&table); - uivector_cleanup(&tablepos1); - uivector_cleanup(&tablepos2); - uivector_cleanup(&initialZerosTable); return error; } @@ -1662,7 +1599,7 @@ static unsigned deflateNoCompression(ucvector* out, const unsigned char* data, s /*non compressed deflate block data: 1 bit BFINAL,2 bits BTYPE,(5 bits): it jumps to start of next byte, 2 bytes LEN, 2 bytes NLEN, LEN bytes literal DATA*/ - size_t i, j, numdeflateblocks = datasize / 65536 + 1; + size_t i, j, numdeflateblocks = (datasize + 65534) / 65535; unsigned datapos = 0; for(i = 0; i < numdeflateblocks; i++) { @@ -1728,8 +1665,9 @@ static void writeLZ77data(size_t* bp, ucvector* out, const uivector* lz77_encode } /*Deflate for a block of type "dynamic", that is, with freely, optimally, created huffman trees*/ -static unsigned deflateDynamic(ucvector* out, const unsigned char* data, size_t datasize, - const LodePNG_CompressSettings* settings) +static unsigned deflateDynamic(ucvector* out, size_t* bp, Hash* hash, + const unsigned char* data, size_t datapos, size_t dataend, + const LodePNGCompressSettings* settings, int final) { unsigned error = 0; @@ -1743,7 +1681,7 @@ static unsigned deflateDynamic(ucvector* out, const unsigned char* data, size_t of code lengths "cl". The code lenghts used to describe this third tree are the code length code lengths ("clcl"). */ - + /*The lz77 encoded data, represented with integers since there will also be length and distance codes in it*/ uivector lz77_encoded; HuffmanTree tree_ll; /*tree for lit,len values*/ @@ -1758,17 +1696,17 @@ static unsigned deflateDynamic(ucvector* out, const unsigned char* data, size_t (these are written as is in the file, it would be crazy to compress these using yet another huffman tree that needs to be represented by yet another set of code lengths)*/ uivector bitlen_cl; + size_t datasize = dataend - datapos; /* Due to the huffman compression of huffman tree representations ("two levels"), there are some anologies: - bitlen_lld is to tree_cl what data is to tree_ll and tree_d. + bitlen_lld is to tree_cl what data is to tree_ll and tree_d. bitlen_lld_e is to bitlen_lld what lz77_encoded is to data. bitlen_cl is to bitlen_lld_e what bitlen_lld is to lz77_encoded. */ - unsigned BFINAL = 1; /*make only one block... the first and final one*/ + unsigned BFINAL = final; size_t numcodes_ll, numcodes_d, i; - size_t bp = 0; /*the bit pointer*/ unsigned HLIT, HDIST, HCLEN; uivector_init(&lz77_encoded); @@ -1782,23 +1720,24 @@ static unsigned deflateDynamic(ucvector* out, const unsigned char* data, size_t uivector_init(&bitlen_lld_e); uivector_init(&bitlen_cl); - /*This while loop is never loops due to a break at the end, it is here to + /*This while loop never loops due to a break at the end, it is here to allow breaking out of it to the cleanup phase on error conditions.*/ while(!error) { - if(settings->useLZ77) + if(settings->use_lz77) { - error = encodeLZ77(&lz77_encoded, data, datasize, settings->windowSize); /*LZ77 encoded*/ + error = encodeLZ77(&lz77_encoded, hash, data, datapos, dataend, settings->windowsize, + settings->minmatch, settings->nicematch, settings->lazymatching); if(error) break; } else { - if(!uivector_resize(&lz77_encoded, datasize)) ERROR_BREAK(9923 /*alloc fail*/); - for(i = 0; i < datasize; i++) lz77_encoded.data[i] = data[i]; /*no LZ77, but still will be Huffman compressed*/ + if(!uivector_resize(&lz77_encoded, datasize)) ERROR_BREAK(83 /*alloc fail*/); + for(i = datapos; i < dataend; i++) lz77_encoded.data[i] = data[i]; /*no LZ77, but still will be Huffman compressed*/ } - if(!uivector_resizev(&frequencies_ll, 286, 0)) ERROR_BREAK(9924 /*alloc fail*/); - if(!uivector_resizev(&frequencies_d, 30, 0)) ERROR_BREAK(9925 /*alloc fail*/); + if(!uivector_resizev(&frequencies_ll, 286, 0)) ERROR_BREAK(83 /*alloc fail*/); + if(!uivector_resizev(&frequencies_d, 30, 0)) ERROR_BREAK(83 /*alloc fail*/); /*Count the frequencies of lit, len and dist codes*/ for(i = 0; i < lz77_encoded.size; i++) @@ -1815,9 +1754,10 @@ static unsigned deflateDynamic(ucvector* out, const unsigned char* data, size_t frequencies_ll.data[256] = 1; /*there will be exactly 1 end code, at the end of the block*/ /*Make both huffman trees, one for the lit and len codes, one for the dist codes*/ - error = HuffmanTree_makeFromFrequencies(&tree_ll, frequencies_ll.data, frequencies_ll.size, 15); + error = HuffmanTree_makeFromFrequencies(&tree_ll, frequencies_ll.data, 257, frequencies_ll.size, 15); if(error) break; - error = HuffmanTree_makeFromFrequencies(&tree_d, frequencies_d.data, frequencies_d.size, 15); + /*2, not 1, is chosen for mincodes: some buggy PNG decoders require at least 2 symbols in the dist tree*/ + error = HuffmanTree_makeFromFrequencies(&tree_d, frequencies_d.data, 2, frequencies_d.size, 15); if(error) break; numcodes_ll = tree_ll.numcodes; if(numcodes_ll > 286) numcodes_ll = 286; @@ -1875,7 +1815,7 @@ static unsigned deflateDynamic(ucvector* out, const unsigned char* data, size_t /*generate tree_cl, the huffmantree of huffmantrees*/ - if(!uivector_resizev(&frequencies_cl, NUM_CODE_LENGTH_CODES, 0)) ERROR_BREAK(9926 /*alloc fail*/); + if(!uivector_resizev(&frequencies_cl, NUM_CODE_LENGTH_CODES, 0)) ERROR_BREAK(83 /*alloc fail*/); for(i = 0; i < bitlen_lld_e.size; i++) { frequencies_cl.data[bitlen_lld_e.data[i]]++; @@ -1884,11 +1824,12 @@ static unsigned deflateDynamic(ucvector* out, const unsigned char* data, size_t if(bitlen_lld_e.data[i] >= 16) i++; } - error = HuffmanTree_makeFromFrequencies(&tree_cl, frequencies_cl.data, frequencies_cl.size, 7); + error = HuffmanTree_makeFromFrequencies(&tree_cl, frequencies_cl.data, + frequencies_cl.size, frequencies_cl.size, 7); if(error) break; - if(!uivector_resize(&bitlen_cl, NUM_CODE_LENGTH_CODES)) ERROR_BREAK(9927 /*alloc fail*/); - for(i = 0; i < NUM_CODE_LENGTH_CODES; i++) + if(!uivector_resize(&bitlen_cl, tree_cl.numcodes)) ERROR_BREAK(83 /*alloc fail*/); + for(i = 0; i < tree_cl.numcodes; i++) { /*lenghts of code length tree is in the order as specified by deflate*/ bitlen_cl.data[i] = HuffmanTree_getLength(&tree_cl, CLCL_ORDER[i]); @@ -1896,13 +1837,13 @@ static unsigned deflateDynamic(ucvector* out, const unsigned char* data, size_t while(bitlen_cl.data[bitlen_cl.size - 1] == 0 && bitlen_cl.size > 4) { /*remove zeros at the end, but minimum size must be 4*/ - if(!uivector_resize(&bitlen_cl, bitlen_cl.size - 1)) ERROR_BREAK(9928 /*alloc fail*/); + if(!uivector_resize(&bitlen_cl, bitlen_cl.size - 1)) ERROR_BREAK(83 /*alloc fail*/); } if(error) break; /* Write everything into the output - + After the BFINAL and BTYPE, the dynamic block consists out of the following: - 5 bits HLIT, 5 bits HDIST, 4 bits HCLEN - (HCLEN+4)*3 bits code lengths of code length alphabet @@ -1915,39 +1856,41 @@ static unsigned deflateDynamic(ucvector* out, const unsigned char* data, size_t */ /*Write block type*/ - addBitToStream(&bp, out, BFINAL); - addBitToStream(&bp, out, 0); /*first bit of BTYPE "dynamic"*/ - addBitToStream(&bp, out, 1); /*second bit of BTYPE "dynamic"*/ + addBitToStream(bp, out, BFINAL); + addBitToStream(bp, out, 0); /*first bit of BTYPE "dynamic"*/ + addBitToStream(bp, out, 1); /*second bit of BTYPE "dynamic"*/ /*write the HLIT, HDIST and HCLEN values*/ HLIT = (unsigned)(numcodes_ll - 257); HDIST = (unsigned)(numcodes_d - 1); HCLEN = (unsigned)bitlen_cl.size - 4; - addBitsToStream(&bp, out, HLIT, 5); - addBitsToStream(&bp, out, HDIST, 5); - addBitsToStream(&bp, out, HCLEN, 4); + /*trim zeroes for HCLEN. HLIT and HDIST were already trimmed at tree creation*/ + while(!bitlen_cl.data[HCLEN + 4 - 1] && HCLEN > 0) HCLEN--; + addBitsToStream(bp, out, HLIT, 5); + addBitsToStream(bp, out, HDIST, 5); + addBitsToStream(bp, out, HCLEN, 4); /*write the code lenghts of the code length alphabet*/ - for(i = 0; i < HCLEN + 4; i++) addBitsToStream(&bp, out, bitlen_cl.data[i], 3); + for(i = 0; i < HCLEN + 4; i++) addBitsToStream(bp, out, bitlen_cl.data[i], 3); /*write the lenghts of the lit/len AND the dist alphabet*/ for(i = 0; i < bitlen_lld_e.size; i++) { - addHuffmanSymbol(&bp, out, HuffmanTree_getCode(&tree_cl, bitlen_lld_e.data[i]), + addHuffmanSymbol(bp, out, HuffmanTree_getCode(&tree_cl, bitlen_lld_e.data[i]), HuffmanTree_getLength(&tree_cl, bitlen_lld_e.data[i])); /*extra bits of repeat codes*/ - if(bitlen_lld_e.data[i] == 16) addBitsToStream(&bp, out, bitlen_lld_e.data[++i], 2); - else if(bitlen_lld_e.data[i] == 17) addBitsToStream(&bp, out, bitlen_lld_e.data[++i], 3); - else if(bitlen_lld_e.data[i] == 18) addBitsToStream(&bp, out, bitlen_lld_e.data[++i], 7); + if(bitlen_lld_e.data[i] == 16) addBitsToStream(bp, out, bitlen_lld_e.data[++i], 2); + else if(bitlen_lld_e.data[i] == 17) addBitsToStream(bp, out, bitlen_lld_e.data[++i], 3); + else if(bitlen_lld_e.data[i] == 18) addBitsToStream(bp, out, bitlen_lld_e.data[++i], 7); } /*write the compressed data symbols*/ - writeLZ77data(&bp, out, &lz77_encoded, &tree_ll, &tree_d); + writeLZ77data(bp, out, &lz77_encoded, &tree_ll, &tree_d); /*error: the length of the end code 256 must be larger than 0*/ if(HuffmanTree_getLength(&tree_ll, 256) == 0) ERROR_BREAK(64); /*write the end code*/ - addHuffmanSymbol(&bp, out, HuffmanTree_getCode(&tree_ll, 256), HuffmanTree_getLength(&tree_ll, 256)); + addHuffmanSymbol(bp, out, HuffmanTree_getCode(&tree_ll, 256), HuffmanTree_getLength(&tree_ll, 256)); break; /*end of error-while*/ } @@ -1967,15 +1910,17 @@ static unsigned deflateDynamic(ucvector* out, const unsigned char* data, size_t return error; } -static unsigned deflateFixed(ucvector* out, const unsigned char* data, - size_t datasize, const LodePNG_CompressSettings* settings) +static unsigned deflateFixed(ucvector* out, size_t* bp, Hash* hash, + const unsigned char* data, + size_t datapos, size_t dataend, + const LodePNGCompressSettings* settings, int final) { HuffmanTree tree_ll; /*tree for literal values and length codes*/ HuffmanTree tree_d; /*tree for distance codes*/ - unsigned BFINAL = 1; /*make only one block... the first and final one*/ + unsigned BFINAL = final; unsigned error = 0; - size_t i, bp = 0; /*the bit pointer*/ + size_t i; HuffmanTree_init(&tree_ll); HuffmanTree_init(&tree_d); @@ -1983,27 +1928,28 @@ static unsigned deflateFixed(ucvector* out, const unsigned char* data, generateFixedLitLenTree(&tree_ll); generateFixedDistanceTree(&tree_d); - addBitToStream(&bp, out, BFINAL); - addBitToStream(&bp, out, 1); /*first bit of BTYPE*/ - addBitToStream(&bp, out, 0); /*second bit of BTYPE*/ + addBitToStream(bp, out, BFINAL); + addBitToStream(bp, out, 1); /*first bit of BTYPE*/ + addBitToStream(bp, out, 0); /*second bit of BTYPE*/ - if(settings->useLZ77) /*LZ77 encoded*/ + if(settings->use_lz77) /*LZ77 encoded*/ { uivector lz77_encoded; uivector_init(&lz77_encoded); - error = encodeLZ77(&lz77_encoded, data, datasize, settings->windowSize); - if(!error) writeLZ77data(&bp, out, &lz77_encoded, &tree_ll, &tree_d); + error = encodeLZ77(&lz77_encoded, hash, data, datapos, dataend, settings->windowsize, + settings->minmatch, settings->nicematch, settings->lazymatching); + if(!error) writeLZ77data(bp, out, &lz77_encoded, &tree_ll, &tree_d); uivector_cleanup(&lz77_encoded); } else /*no LZ77, but still will be Huffman compressed*/ { - for(i = 0; i < datasize; i++) + for(i = datapos; i < dataend; i++) { - addHuffmanSymbol(&bp, out, HuffmanTree_getCode(&tree_ll, data[i]), HuffmanTree_getLength(&tree_ll, data[i])); + addHuffmanSymbol(bp, out, HuffmanTree_getCode(&tree_ll, data[i]), HuffmanTree_getLength(&tree_ll, data[i])); } } /*add END code*/ - if(!error) addHuffmanSymbol(&bp, out, HuffmanTree_getCode(&tree_ll, 256), HuffmanTree_getLength(&tree_ll, 256)); + if(!error) addHuffmanSymbol(bp, out, HuffmanTree_getCode(&tree_ll, 256), HuffmanTree_getLength(&tree_ll, 256)); /*cleanup*/ HuffmanTree_cleanup(&tree_ll); @@ -2012,17 +1958,72 @@ static unsigned deflateFixed(ucvector* out, const unsigned char* data, return error; } -static unsigned LodePNG_deflate(ucvector* out, const unsigned char* data, size_t datasize, - const LodePNG_CompressSettings* settings) +static unsigned lodepng_deflatev(ucvector* out, const unsigned char* in, size_t insize, + const LodePNGCompressSettings* settings) { unsigned error = 0; - if(settings->btype == 0) error = deflateNoCompression(out, data, datasize); - else if(settings->btype == 1) error = deflateFixed(out, data, datasize, settings); - else if(settings->btype == 2) error = deflateDynamic(out, data, datasize, settings); - else error = 61; + size_t i, blocksize, numdeflateblocks; + size_t bp = 0; /*the bit pointer*/ + Hash hash; + + if(settings->btype > 2) return 61; + else if(settings->btype == 0) return deflateNoCompression(out, in, insize); + else if(settings->btype == 1) blocksize = insize; + else /*if(settings->btype == 2)*/ + { + blocksize = insize / 8 + 8; + if(blocksize < 65535) blocksize = 65535; + } + + numdeflateblocks = (insize + blocksize - 1) / blocksize; + if(numdeflateblocks == 0) numdeflateblocks = 1; + + error = hash_init(&hash, settings->windowsize); + if(error) return error; + + for(i = 0; i < numdeflateblocks && !error; i++) + { + int final = i == numdeflateblocks - 1; + size_t start = i * blocksize; + size_t end = start + blocksize; + if(end > insize) end = insize; + + if(settings->btype == 1) error = deflateFixed(out, &bp, &hash, in, start, end, settings, final); + else if(settings->btype == 2) error = deflateDynamic(out, &bp, &hash, in, start, end, settings, final); + } + + hash_cleanup(&hash); + return error; } +unsigned lodepng_deflate(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGCompressSettings* settings) +{ + unsigned error; + ucvector v; + ucvector_init_buffer(&v, *out, *outsize); + error = lodepng_deflatev(&v, in, insize, settings); + *out = v.data; + *outsize = v.size; + return error; +} + +static unsigned deflate(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGCompressSettings* settings) +{ + if(settings->custom_deflate) + { + return settings->custom_deflate(out, outsize, in, insize, settings); + } + else + { + return lodepng_deflate(out, outsize, in, insize, settings); + } +} + #endif /*LODEPNG_COMPILE_DECODER*/ /* ////////////////////////////////////////////////////////////////////////// */ @@ -2041,8 +2042,8 @@ static unsigned update_adler32(unsigned adler, const unsigned char* data, unsign len -= amount; while(amount > 0) { - s1 = (s1 + *data++); - s2 = (s2 + s1); + s1 += (*data++); + s2 += s1; amount--; } s1 %= 65521; @@ -2064,12 +2065,11 @@ static unsigned adler32(const unsigned char* data, unsigned len) #ifdef LODEPNG_COMPILE_DECODER -unsigned LodePNG_zlib_decompress(unsigned char** out, size_t* outsize, const unsigned char* in, - size_t insize, const LodePNG_DecompressSettings* settings) +unsigned lodepng_zlib_decompress(unsigned char** out, size_t* outsize, const unsigned char* in, + size_t insize, const LodePNGDecompressSettings* settings) { unsigned error = 0; unsigned CM, CINFO, FDICT; - ucvector outv; if(insize < 2) return 53; /*error, size of zlib data too small*/ /*read information from zlib header*/ @@ -2097,35 +2097,42 @@ unsigned LodePNG_zlib_decompress(unsigned char** out, size_t* outsize, const uns return 26; } - /*ucvector-controlled version of the output buffer, for dynamic array*/ - ucvector_init_buffer(&outv, *out, *outsize); - error = LodePNG_inflate(&outv, in, insize, 2); - *out = outv.data; - *outsize = outv.size; + error = inflate(out, outsize, in + 2, insize - 2, settings); if(error) return error; - if(!settings->ignoreAdler32) + if(!settings->ignore_adler32) { - unsigned ADLER32 = LodePNG_read32bitInt(&in[insize - 4]); - unsigned checksum = adler32(outv.data, (unsigned)outv.size); + unsigned ADLER32 = lodepng_read32bitInt(&in[insize - 4]); + unsigned checksum = adler32(*out, (unsigned)(*outsize)); if(checksum != ADLER32) return 58; /*error, adler checksum not correct, data must be corrupted*/ } return 0; /*no error*/ } +static unsigned zlib_decompress(unsigned char** out, size_t* outsize, const unsigned char* in, + size_t insize, const LodePNGDecompressSettings* settings) +{ + if(settings->custom_zlib) + return settings->custom_zlib(out, outsize, in, insize, settings); + else + return lodepng_zlib_decompress(out, outsize, in, insize, settings); +} + #endif /*LODEPNG_COMPILE_DECODER*/ #ifdef LODEPNG_COMPILE_ENCODER -unsigned LodePNG_zlib_compress(unsigned char** out, size_t* outsize, const unsigned char* in, - size_t insize, const LodePNG_CompressSettings* settings) +unsigned lodepng_zlib_compress(unsigned char** out, size_t* outsize, const unsigned char* in, + size_t insize, const LodePNGCompressSettings* settings) { /*initially, *out must be NULL and outsize 0, if you just give some random *out that's pointing to a non allocated buffer, this'll crash*/ - ucvector deflatedata, outv; + ucvector outv; size_t i; unsigned error; + unsigned char* deflatedata = 0; + size_t deflatesize = 0; unsigned ADLER32; /*zlib data: 1 byte CMF (CM+CINFO), 1 byte FLG, deflate data, 4 byte ADLER32 checksum of the Decompressed data*/ @@ -2142,15 +2149,14 @@ unsigned LodePNG_zlib_compress(unsigned char** out, size_t* outsize, const unsig ucvector_push_back(&outv, (unsigned char)(CMFFLG / 256)); ucvector_push_back(&outv, (unsigned char)(CMFFLG % 256)); - ucvector_init(&deflatedata); - error = LodePNG_deflate(&deflatedata, in, insize, settings); + error = deflate(&deflatedata, &deflatesize, in, insize, settings); if(!error) { ADLER32 = adler32(in, (unsigned)insize); - for(i = 0; i < deflatedata.size; i++) ucvector_push_back(&outv, deflatedata.data[i]); - ucvector_cleanup(&deflatedata); - LodePNG_add32bitInt(&outv, ADLER32); + for(i = 0; i < deflatesize; i++) ucvector_push_back(&outv, deflatedata[i]); + free(deflatedata); + lodepng_add32bitInt(&outv, ADLER32); } *out = outv.data; @@ -2159,32 +2165,38 @@ unsigned LodePNG_zlib_compress(unsigned char** out, size_t* outsize, const unsig return error; } +/* compress using the default or custom zlib function */ +static unsigned zlib_compress(unsigned char** out, size_t* outsize, const unsigned char* in, + size_t insize, const LodePNGCompressSettings* settings) +{ + if(settings->custom_zlib) + { + return settings->custom_zlib(out, outsize, in, insize, settings); + } + else + { + return lodepng_zlib_compress(out, outsize, in, insize, settings); + } +} + #endif /*LODEPNG_COMPILE_ENCODER*/ #else /*no LODEPNG_COMPILE_ZLIB*/ -/* -Dummy functions used if LODEPNG_COMPILE_ZLIB isn't defined. You need to implement -these yourself when disabling the LodePNG Zlib part, e.g. by calling another -library from here. - -*out must be NULL and *outsize must be 0 initially, and after the function is done, -*out must point to the decompressed data, *outsize must be the size of it, and must -be the size of the useful data in bytes, not the alloc size. -*/ - #ifdef LODEPNG_COMPILE_DECODER -static unsigned LodePNG_zlib_decompress(unsigned char** out, size_t* outsize, const unsigned char* in, - size_t insize, const LodePNG_DecompressSettings* settings) +static unsigned zlib_decompress(unsigned char** out, size_t* outsize, const unsigned char* in, + size_t insize, const LodePNGDecompressSettings* settings) { - return 0; //Placeholder to be implemented if LODEPNG_COMPILE_ZLIB is disabled. + if (!settings->custom_zlib) return 87; /*no custom zlib function provided */ + return settings->custom_zlib(out, outsize, in, insize, settings); } #endif /*LODEPNG_COMPILE_DECODER*/ #ifdef LODEPNG_COMPILE_ENCODER -static unsigned LodePNG_zlib_compress(unsigned char** out, size_t* outsize, const unsigned char* in, - size_t insize, const LodePNG_CompressSettings* settings) +static unsigned zlib_compress(unsigned char** out, size_t* outsize, const unsigned char* in, + size_t insize, const LodePNGCompressSettings* settings) { - return 0; //Placeholder to be implemented if LODEPNG_COMPILE_ZLIB is disabled. + if (!settings->custom_zlib) return 87; /*no custom zlib function provided */ + return settings->custom_zlib(out, outsize, in, insize, settings); } #endif /*LODEPNG_COMPILE_ENCODER*/ @@ -2197,26 +2209,38 @@ static unsigned LodePNG_zlib_compress(unsigned char** out, size_t* outsize, cons /*this is a good tradeoff between speed and compression ratio*/ #define DEFAULT_WINDOWSIZE 2048 -void LodePNG_CompressSettings_init(LodePNG_CompressSettings* settings) +void lodepng_compress_settings_init(LodePNGCompressSettings* settings) { /*compress with dynamic huffman tree (not in the mathematical sense, just not the predefined one)*/ settings->btype = 2; - settings->useLZ77 = 1; - settings->windowSize = DEFAULT_WINDOWSIZE; + settings->use_lz77 = 1; + settings->windowsize = DEFAULT_WINDOWSIZE; + settings->minmatch = 3; + settings->nicematch = 128; + settings->lazymatching = 1; + + settings->custom_zlib = 0; + settings->custom_deflate = 0; + settings->custom_context = 0; } -const LodePNG_CompressSettings LodePNG_defaultCompressSettings = {2, 1, DEFAULT_WINDOWSIZE}; +const LodePNGCompressSettings lodepng_default_compress_settings = {2, 1, DEFAULT_WINDOWSIZE, 3, 128, 1, 0, 0, 0}; + #endif /*LODEPNG_COMPILE_ENCODER*/ #ifdef LODEPNG_COMPILE_DECODER -void LodePNG_DecompressSettings_init(LodePNG_DecompressSettings* settings) +void lodepng_decompress_settings_init(LodePNGDecompressSettings* settings) { - settings->ignoreAdler32 = 0; + settings->ignore_adler32 = 0; + + settings->custom_zlib = 0; + settings->custom_inflate = 0; + settings->custom_context = 0; } -const LodePNG_DecompressSettings LodePNG_defaultDecompressSettings = {0}; +const LodePNGDecompressSettings lodepng_default_decompress_settings = {0, 0, 0, 0}; #endif /*LODEPNG_COMPILE_DECODER*/ @@ -2269,7 +2293,7 @@ static unsigned Crc32_update_crc(const unsigned char* buf, unsigned crc, size_t } /*Return the CRC of the bytes buf[0..len-1].*/ -static unsigned Crc32_crc(const unsigned char* buf, size_t len) +unsigned lodepng_crc32(const unsigned char* buf, size_t len) { return Crc32_update_crc(buf, 0xffffffffL, len) ^ 0xffffffffL; } @@ -2321,88 +2345,88 @@ static void setBitOfReversedStream(size_t* bitpointer, unsigned char* bitstream, /* / PNG chunks / */ /* ////////////////////////////////////////////////////////////////////////// */ -unsigned LodePNG_chunk_length(const unsigned char* chunk) +unsigned lodepng_chunk_length(const unsigned char* chunk) { - return LodePNG_read32bitInt(&chunk[0]); + return lodepng_read32bitInt(&chunk[0]); } -void LodePNG_chunk_type(char type[5], const unsigned char* chunk) +void lodepng_chunk_type(char type[5], const unsigned char* chunk) { unsigned i; for(i = 0; i < 4; i++) type[i] = chunk[4 + i]; type[4] = 0; /*null termination char*/ } -unsigned char LodePNG_chunk_type_equals(const unsigned char* chunk, const char* type) +unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type) { if(strlen(type) != 4) return 0; return (chunk[4] == type[0] && chunk[5] == type[1] && chunk[6] == type[2] && chunk[7] == type[3]); } -unsigned char LodePNG_chunk_critical(const unsigned char* chunk) +unsigned char lodepng_chunk_ancillary(const unsigned char* chunk) { - return((chunk[4] & 32) == 0); + return((chunk[4] & 32) != 0); } -unsigned char LodePNG_chunk_private(const unsigned char* chunk) +unsigned char lodepng_chunk_private(const unsigned char* chunk) { return((chunk[6] & 32) != 0); } -unsigned char LodePNG_chunk_safetocopy(const unsigned char* chunk) +unsigned char lodepng_chunk_safetocopy(const unsigned char* chunk) { return((chunk[7] & 32) != 0); } -unsigned char* LodePNG_chunk_data(unsigned char* chunk) +unsigned char* lodepng_chunk_data(unsigned char* chunk) { return &chunk[8]; } -const unsigned char* LodePNG_chunk_data_const(const unsigned char* chunk) +const unsigned char* lodepng_chunk_data_const(const unsigned char* chunk) { return &chunk[8]; } -unsigned LodePNG_chunk_check_crc(const unsigned char* chunk) +unsigned lodepng_chunk_check_crc(const unsigned char* chunk) { - unsigned length = LodePNG_chunk_length(chunk); - unsigned CRC = LodePNG_read32bitInt(&chunk[length + 8]); + unsigned length = lodepng_chunk_length(chunk); + unsigned CRC = lodepng_read32bitInt(&chunk[length + 8]); /*the CRC is taken of the data and the 4 chunk type letters, not the length*/ - unsigned checksum = Crc32_crc(&chunk[4], length + 4); + unsigned checksum = lodepng_crc32(&chunk[4], length + 4); if(CRC != checksum) return 1; else return 0; } -void LodePNG_chunk_generate_crc(unsigned char* chunk) +void lodepng_chunk_generate_crc(unsigned char* chunk) { - unsigned length = LodePNG_chunk_length(chunk); - unsigned CRC = Crc32_crc(&chunk[4], length + 4); - LodePNG_set32bitInt(chunk + 8 + length, CRC); + unsigned length = lodepng_chunk_length(chunk); + unsigned CRC = lodepng_crc32(&chunk[4], length + 4); + lodepng_set32bitInt(chunk + 8 + length, CRC); } -unsigned char* LodePNG_chunk_next(unsigned char* chunk) +unsigned char* lodepng_chunk_next(unsigned char* chunk) { - unsigned total_chunk_length = LodePNG_chunk_length(chunk) + 12; + unsigned total_chunk_length = lodepng_chunk_length(chunk) + 12; return &chunk[total_chunk_length]; } -const unsigned char* LodePNG_chunk_next_const(const unsigned char* chunk) +const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk) { - unsigned total_chunk_length = LodePNG_chunk_length(chunk) + 12; + unsigned total_chunk_length = lodepng_chunk_length(chunk) + 12; return &chunk[total_chunk_length]; } -unsigned LodePNG_append_chunk(unsigned char** out, size_t* outlength, const unsigned char* chunk) +unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk) { unsigned i; - unsigned total_chunk_length = LodePNG_chunk_length(chunk) + 12; + unsigned total_chunk_length = lodepng_chunk_length(chunk) + 12; unsigned char *chunk_start, *new_buffer; size_t new_length = (*outlength) + total_chunk_length; if(new_length < total_chunk_length || new_length < (*outlength)) return 77; /*integer overflow happened*/ - new_buffer = (unsigned char*)realloc(*out, new_length); - if(!new_buffer) return 9929; /*alloc fail*/ + new_buffer = (unsigned char*)myrealloc(*out, new_length); + if(!new_buffer) return 83; /*alloc fail*/ (*out) = new_buffer; (*outlength) = new_length; chunk_start = &(*out)[new_length - total_chunk_length]; @@ -2412,21 +2436,21 @@ unsigned LodePNG_append_chunk(unsigned char** out, size_t* outlength, const unsi return 0; } -unsigned LodePNG_create_chunk(unsigned char** out, size_t* outlength, unsigned length, +unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length, const char* type, const unsigned char* data) { unsigned i; unsigned char *chunk, *new_buffer; size_t new_length = (*outlength) + length + 12; if(new_length < length + 12 || new_length < (*outlength)) return 77; /*integer overflow happened*/ - new_buffer = (unsigned char*)realloc(*out, new_length); - if(!new_buffer) return 9930; /*alloc fail*/ + new_buffer = (unsigned char*)myrealloc(*out, new_length); + if(!new_buffer) return 83; /*alloc fail*/ (*out) = new_buffer; (*outlength) = new_length; chunk = &(*out)[(*outlength) - length - 12]; /*1: length*/ - LodePNG_set32bitInt(chunk, (unsigned)length); + lodepng_set32bitInt(chunk, (unsigned)length); /*2: chunk name (4 letters)*/ chunk[4] = type[0]; @@ -2438,7 +2462,7 @@ unsigned LodePNG_create_chunk(unsigned char** out, size_t* outlength, unsigned l for(i = 0; i < length; i++) chunk[8 + i] = data[i]; /*4: CRC (of the chunkname characters and the data)*/ - LodePNG_chunk_generate_crc(chunk); + lodepng_chunk_generate_crc(chunk); return 0; } @@ -2448,9 +2472,9 @@ unsigned LodePNG_create_chunk(unsigned char** out, size_t* outlength, unsigned l /* ////////////////////////////////////////////////////////////////////////// */ /*return type is a LodePNG error code*/ -static unsigned checkColorValidity(unsigned colorType, unsigned bd) /*bd = bitDepth*/ +static unsigned checkColorValidity(LodePNGColorType colortype, unsigned bd) /*bd = bitdepth*/ { - switch(colorType) + switch(colortype) { case 0: if(!(bd == 1 || bd == 2 || bd == 4 || bd == 8 || bd == 16)) return 37; break; /*grey*/ case 2: if(!( bd == 8 || bd == 16)) return 37; break; /*RGB*/ @@ -2462,9 +2486,9 @@ static unsigned checkColorValidity(unsigned colorType, unsigned bd) /*bd = bitDe return 0; /*allowed color type / bits combination*/ } -static unsigned getNumColorChannels(unsigned colorType) +static unsigned getNumColorChannels(LodePNGColorType colortype) { - switch(colorType) + switch(colortype) { case 0: return 1; /*grey*/ case 2: return 3; /*RGB*/ @@ -2475,37 +2499,71 @@ static unsigned getNumColorChannels(unsigned colorType) return 0; /*unexisting color type*/ } -static unsigned getBpp(unsigned colorType, unsigned bitDepth) +static unsigned lodepng_get_bpp_lct(LodePNGColorType colortype, unsigned bitdepth) { /*bits per pixel is amount of channels * bits per channel*/ - return getNumColorChannels(colorType) * bitDepth; + return getNumColorChannels(colortype) * bitdepth; } /* ////////////////////////////////////////////////////////////////////////// */ -void LodePNG_InfoColor_init(LodePNG_InfoColor* info) +void lodepng_color_mode_init(LodePNGColorMode* info) { info->key_defined = 0; info->key_r = info->key_g = info->key_b = 0; - info->colorType = 6; - info->bitDepth = 8; + info->colortype = LCT_RGBA; + info->bitdepth = 8; info->palette = 0; info->palettesize = 0; } -void LodePNG_InfoColor_cleanup(LodePNG_InfoColor* info) +void lodepng_color_mode_cleanup(LodePNGColorMode* info) { - LodePNG_InfoColor_clearPalette(info); + lodepng_palette_clear(info); } -void LodePNG_InfoColor_clearPalette(LodePNG_InfoColor* info) +unsigned lodepng_color_mode_copy(LodePNGColorMode* dest, const LodePNGColorMode* source) { - if(info->palette) free(info->palette); + size_t i; + lodepng_color_mode_cleanup(dest); + *dest = *source; + if(source->palette) + { + dest->palette = (unsigned char*)mymalloc(source->palettesize * 4); + if(!dest->palette && source->palettesize) return 83; /*alloc fail*/ + for(i = 0; i < source->palettesize * 4; i++) dest->palette[i] = source->palette[i]; + } + return 0; +} + +static int lodepng_color_mode_equal(const LodePNGColorMode* a, const LodePNGColorMode* b) +{ + size_t i; + if(a->colortype != b->colortype) return 0; + if(a->bitdepth != b->bitdepth) return 0; + if(a->key_defined != b->key_defined) return 0; + if(a->key_defined) + { + if(a->key_r != b->key_r) return 0; + if(a->key_g != b->key_g) return 0; + if(a->key_b != b->key_b) return 0; + } + if(a->palettesize != b->palettesize) return 0; + for(i = 0; i < a->palettesize * 4; i++) + { + if(a->palette[i] != b->palette[i]) return 0; + } + return 1; +} + +void lodepng_palette_clear(LodePNGColorMode* info) +{ + if(info->palette) myfree(info->palette); info->palettesize = 0; } -unsigned LodePNG_InfoColor_addPalette(LodePNG_InfoColor* info, - unsigned char r, unsigned char g, unsigned char b, unsigned char a) +unsigned lodepng_palette_add(LodePNGColorMode* info, + unsigned char r, unsigned char g, unsigned char b, unsigned char a) { unsigned char* data; /*the same resize technique as C++ std::vectors is used, and here it's made so that for a palette with @@ -2514,8 +2572,8 @@ unsigned LodePNG_InfoColor_addPalette(LodePNG_InfoColor* info, { /*allocated data must be at least 4* palettesize (for 4 color bytes)*/ size_t alloc_size = info->palettesize == 0 ? 4 : info->palettesize * 4 * 2; - data = (unsigned char*)realloc(info->palette, alloc_size); - if(!data) return 9931; /*alloc fail*/ + data = (unsigned char*)myrealloc(info->palette, alloc_size); + if(!data) return 83; /*alloc fail*/ else info->palette = data; } info->palette[4 * info->palettesize + 0] = r; @@ -2526,33 +2584,33 @@ unsigned LodePNG_InfoColor_addPalette(LodePNG_InfoColor* info, return 0; } -unsigned LodePNG_InfoColor_getBpp(const LodePNG_InfoColor* info) +unsigned lodepng_get_bpp(const LodePNGColorMode* info) { - /*calculate bits per pixel out of colorType and bitDepth*/ - return getBpp(info->colorType, info->bitDepth); + /*calculate bits per pixel out of colortype and bitdepth*/ + return lodepng_get_bpp_lct(info->colortype, info->bitdepth); } -unsigned LodePNG_InfoColor_getChannels(const LodePNG_InfoColor* info) +unsigned lodepng_get_channels(const LodePNGColorMode* info) { - return getNumColorChannels(info->colorType); + return getNumColorChannels(info->colortype); } -unsigned LodePNG_InfoColor_isGreyscaleType(const LodePNG_InfoColor* info) +unsigned lodepng_is_greyscale_type(const LodePNGColorMode* info) { - return info->colorType == 0 || info->colorType == 4; + return info->colortype == LCT_GREY || info->colortype == LCT_GREY_ALPHA; } -unsigned LodePNG_InfoColor_isAlphaType(const LodePNG_InfoColor* info) +unsigned lodepng_is_alpha_type(const LodePNGColorMode* info) { - return (info->colorType & 4) != 0; + return (info->colortype & 4) != 0; /*4 or 6*/ } -unsigned LodePNG_InfoColor_isPaletteType(const LodePNG_InfoColor* info) +unsigned lodepng_is_palette_type(const LodePNGColorMode* info) { - return info->colorType == 3; + return info->colortype == LCT_PALETTE; } -unsigned LodePNG_InfoColor_hasPaletteAlpha(const LodePNG_InfoColor* info) +unsigned lodepng_has_palette_alpha(const LodePNGColorMode* info) { size_t i; for(i = 0; i < info->palettesize; i++) @@ -2562,772 +2620,1228 @@ unsigned LodePNG_InfoColor_hasPaletteAlpha(const LodePNG_InfoColor* info) return 0; } -unsigned LodePNG_InfoColor_canHaveAlpha(const LodePNG_InfoColor* info) +unsigned lodepng_can_have_alpha(const LodePNGColorMode* info) { return info->key_defined - || LodePNG_InfoColor_isAlphaType(info) - || LodePNG_InfoColor_hasPaletteAlpha(info); + || lodepng_is_alpha_type(info) + || lodepng_has_palette_alpha(info); } -unsigned LodePNG_InfoColor_equal(const LodePNG_InfoColor* info1, const LodePNG_InfoColor* info2) +size_t lodepng_get_raw_size(unsigned w, unsigned h, const LodePNGColorMode* color) { - return info1->colorType == info2->colorType - && info1->bitDepth == info2->bitDepth; /*palette and color key not compared*/ + return (w * h * lodepng_get_bpp(color) + 7) / 8; } -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS -void LodePNG_UnknownChunks_init(LodePNG_UnknownChunks* chunks) +size_t lodepng_get_raw_size_lct(unsigned w, unsigned h, LodePNGColorType colortype, unsigned bitdepth) +{ + return (w * h * lodepng_get_bpp_lct(colortype, bitdepth) + 7) / 8; +} + +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + +static void LodePNGUnknownChunks_init(LodePNGInfo* info) { unsigned i; - for(i = 0; i < 3; i++) chunks->data[i] = 0; - for(i = 0; i < 3; i++) chunks->datasize[i] = 0; + for(i = 0; i < 3; i++) info->unknown_chunks_data[i] = 0; + for(i = 0; i < 3; i++) info->unknown_chunks_size[i] = 0; } -void LodePNG_UnknownChunks_cleanup(LodePNG_UnknownChunks* chunks) +static void LodePNGUnknownChunks_cleanup(LodePNGInfo* info) { unsigned i; - for(i = 0; i < 3; i++) free(chunks->data[i]); + for(i = 0; i < 3; i++) myfree(info->unknown_chunks_data[i]); } -unsigned LodePNG_UnknownChunks_copy(LodePNG_UnknownChunks* dest, const LodePNG_UnknownChunks* src) +static unsigned LodePNGUnknownChunks_copy(LodePNGInfo* dest, const LodePNGInfo* src) { unsigned i; - LodePNG_UnknownChunks_cleanup(dest); + LodePNGUnknownChunks_cleanup(dest); for(i = 0; i < 3; i++) { size_t j; - dest->datasize[i] = src->datasize[i]; - dest->data[i] = (unsigned char*)malloc(src->datasize[i]); - if(!dest->data[i] && dest->datasize[i]) return 9932; /*alloc fail*/ - for(j = 0; j < src->datasize[i]; j++) dest->data[i][j] = src->data[i][j]; + dest->unknown_chunks_size[i] = src->unknown_chunks_size[i]; + dest->unknown_chunks_data[i] = (unsigned char*)mymalloc(src->unknown_chunks_size[i]); + if(!dest->unknown_chunks_data[i] && dest->unknown_chunks_size[i]) return 83; /*alloc fail*/ + for(j = 0; j < src->unknown_chunks_size[i]; j++) + { + dest->unknown_chunks_data[i][j] = src->unknown_chunks_data[i][j]; + } } return 0; } -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS -void LodePNG_Text_init(LodePNG_Text* text) -{ - text->num = 0; - text->keys = NULL; - text->strings = NULL; -} - -void LodePNG_Text_cleanup(LodePNG_Text* text) -{ - LodePNG_Text_clear(text); -} - -unsigned LodePNG_Text_copy(LodePNG_Text* dest, const LodePNG_Text* source) -{ - size_t i = 0; - dest->keys = 0; - dest->strings = 0; - dest->num = 0; - for(i = 0; i < source->num; i++) - { - unsigned error = LodePNG_Text_add(dest, source->keys[i], source->strings[i]); - if(error) return error; - } - return 0; -} - -void LodePNG_Text_clear(LodePNG_Text* text) -{ - size_t i; - for(i = 0; i < text->num; i++) - { - string_cleanup(&text->keys[i]); - string_cleanup(&text->strings[i]); - } - free(text->keys); - free(text->strings); -} - -unsigned LodePNG_Text_add(LodePNG_Text* text, const char* key, const char* str) -{ - char** new_keys = (char**)(realloc(text->keys, sizeof(char*) * (text->num + 1))); - char** new_strings = (char**)(realloc(text->strings, sizeof(char*) * (text->num + 1))); - if(!new_keys || !new_strings) - { - free(new_keys); - free(new_strings); - return 9933; /*alloc fail*/ - } - - text->num++; - text->keys = new_keys; - text->strings = new_strings; - - string_init(&text->keys[text->num - 1]); - string_set(&text->keys[text->num - 1], key); - - string_init(&text->strings[text->num - 1]); - string_set(&text->strings[text->num - 1], str); - - return 0; -} /******************************************************************************/ -void LodePNG_IText_init(LodePNG_IText* text) +static void LodePNGText_init(LodePNGInfo* info) { - text->num = 0; - text->keys = NULL; - text->langtags = NULL; - text->transkeys = NULL; - text->strings = NULL; + info->text_num = 0; + info->text_keys = NULL; + info->text_strings = NULL; } -void LodePNG_IText_cleanup(LodePNG_IText* text) +static void LodePNGText_cleanup(LodePNGInfo* info) { - LodePNG_IText_clear(text); + size_t i; + for(i = 0; i < info->text_num; i++) + { + string_cleanup(&info->text_keys[i]); + string_cleanup(&info->text_strings[i]); + } + myfree(info->text_keys); + myfree(info->text_strings); } -unsigned LodePNG_IText_copy(LodePNG_IText* dest, const LodePNG_IText* source) +static unsigned LodePNGText_copy(LodePNGInfo* dest, const LodePNGInfo* source) { size_t i = 0; - dest->keys = 0; - dest->langtags = 0; - dest->transkeys = 0; - dest->strings = 0; - dest->num = 0; - for(i = 0; i < source->num; i++) + dest->text_keys = 0; + dest->text_strings = 0; + dest->text_num = 0; + for(i = 0; i < source->text_num; i++) { - unsigned error = LodePNG_IText_add(dest, source->keys[i], source->langtags[i], - source->transkeys[i], source->strings[i]); - if(error) return error; + CERROR_TRY_RETURN(lodepng_add_text(dest, source->text_keys[i], source->text_strings[i])); } return 0; } -void LodePNG_IText_clear(LodePNG_IText* text) +void lodepng_clear_text(LodePNGInfo* info) { - size_t i; - for(i = 0; i < text->num; i++) - { - string_cleanup(&text->keys[i]); - string_cleanup(&text->langtags[i]); - string_cleanup(&text->transkeys[i]); - string_cleanup(&text->strings[i]); - } - free(text->keys); - free(text->langtags); - free(text->transkeys); - free(text->strings); + LodePNGText_cleanup(info); } -unsigned LodePNG_IText_add(LodePNG_IText* text, const char* key, const char* langtag, - const char* transkey, const char* str) +unsigned lodepng_add_text(LodePNGInfo* info, const char* key, const char* str) { - char** new_keys = (char**)(realloc(text->keys, sizeof(char*) * (text->num + 1))); - char** new_langtags = (char**)(realloc(text->langtags, sizeof(char*) * (text->num + 1))); - char** new_transkeys = (char**)(realloc(text->transkeys, sizeof(char*) * (text->num + 1))); - char** new_strings = (char**)(realloc(text->strings, sizeof(char*) * (text->num + 1))); - if(!new_keys || !new_langtags || !new_transkeys || !new_strings) + char** new_keys = (char**)(myrealloc(info->text_keys, sizeof(char*) * (info->text_num + 1))); + char** new_strings = (char**)(myrealloc(info->text_strings, sizeof(char*) * (info->text_num + 1))); + if(!new_keys || !new_strings) { - free(new_keys); - free(new_langtags); - free(new_transkeys); - free(new_strings); - return 9934; /*alloc fail*/ + myfree(new_keys); + myfree(new_strings); + return 83; /*alloc fail*/ } - text->num++; - text->keys = new_keys; - text->langtags = new_langtags; - text->transkeys = new_transkeys; - text->strings = new_strings; + info->text_num++; + info->text_keys = new_keys; + info->text_strings = new_strings; - string_init(&text->keys[text->num - 1]); - string_set(&text->keys[text->num - 1], key); + string_init(&info->text_keys[info->text_num - 1]); + string_set(&info->text_keys[info->text_num - 1], key); - string_init(&text->langtags[text->num - 1]); - string_set(&text->langtags[text->num - 1], langtag); + string_init(&info->text_strings[info->text_num - 1]); + string_set(&info->text_strings[info->text_num - 1], str); - string_init(&text->transkeys[text->num - 1]); - string_set(&text->transkeys[text->num - 1], transkey); + return 0; +} - string_init(&text->strings[text->num - 1]); - string_set(&text->strings[text->num - 1], str); +/******************************************************************************/ + +static void LodePNGIText_init(LodePNGInfo* info) +{ + info->itext_num = 0; + info->itext_keys = NULL; + info->itext_langtags = NULL; + info->itext_transkeys = NULL; + info->itext_strings = NULL; +} + +static void LodePNGIText_cleanup(LodePNGInfo* info) +{ + size_t i; + for(i = 0; i < info->itext_num; i++) + { + string_cleanup(&info->itext_keys[i]); + string_cleanup(&info->itext_langtags[i]); + string_cleanup(&info->itext_transkeys[i]); + string_cleanup(&info->itext_strings[i]); + } + myfree(info->itext_keys); + myfree(info->itext_langtags); + myfree(info->itext_transkeys); + myfree(info->itext_strings); +} + +static unsigned LodePNGIText_copy(LodePNGInfo* dest, const LodePNGInfo* source) +{ + size_t i = 0; + dest->itext_keys = 0; + dest->itext_langtags = 0; + dest->itext_transkeys = 0; + dest->itext_strings = 0; + dest->itext_num = 0; + for(i = 0; i < source->itext_num; i++) + { + CERROR_TRY_RETURN(lodepng_add_itext(dest, source->itext_keys[i], source->itext_langtags[i], + source->itext_transkeys[i], source->itext_strings[i])); + } + return 0; +} + +void lodepng_clear_itext(LodePNGInfo* info) +{ + LodePNGIText_cleanup(info); +} + +unsigned lodepng_add_itext(LodePNGInfo* info, const char* key, const char* langtag, + const char* transkey, const char* str) +{ + char** new_keys = (char**)(myrealloc(info->itext_keys, sizeof(char*) * (info->itext_num + 1))); + char** new_langtags = (char**)(myrealloc(info->itext_langtags, sizeof(char*) * (info->itext_num + 1))); + char** new_transkeys = (char**)(myrealloc(info->itext_transkeys, sizeof(char*) * (info->itext_num + 1))); + char** new_strings = (char**)(myrealloc(info->itext_strings, sizeof(char*) * (info->itext_num + 1))); + if(!new_keys || !new_langtags || !new_transkeys || !new_strings) + { + myfree(new_keys); + myfree(new_langtags); + myfree(new_transkeys); + myfree(new_strings); + return 83; /*alloc fail*/ + } + + info->itext_num++; + info->itext_keys = new_keys; + info->itext_langtags = new_langtags; + info->itext_transkeys = new_transkeys; + info->itext_strings = new_strings; + + string_init(&info->itext_keys[info->itext_num - 1]); + string_set(&info->itext_keys[info->itext_num - 1], key); + + string_init(&info->itext_langtags[info->itext_num - 1]); + string_set(&info->itext_langtags[info->itext_num - 1], langtag); + + string_init(&info->itext_transkeys[info->itext_num - 1]); + string_set(&info->itext_transkeys[info->itext_num - 1], transkey); + + string_init(&info->itext_strings[info->itext_num - 1]); + string_set(&info->itext_strings[info->itext_num - 1], str); return 0; } #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -void LodePNG_InfoPng_init(LodePNG_InfoPng* info) +void lodepng_info_init(LodePNGInfo* info) { - info->width = info->height = 0; - LodePNG_InfoColor_init(&info->color); - info->interlaceMethod = 0; - info->compressionMethod = 0; - info->filterMethod = 0; + lodepng_color_mode_init(&info->color); + info->interlace_method = 0; + info->compression_method = 0; + info->filter_method = 0; #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS info->background_defined = 0; info->background_r = info->background_g = info->background_b = 0; - LodePNG_Text_init(&info->text); - LodePNG_IText_init(&info->itext); + LodePNGText_init(info); + LodePNGIText_init(info); info->time_defined = 0; info->phys_defined = 0; + + LodePNGUnknownChunks_init(info); #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS - LodePNG_UnknownChunks_init(&info->unknown_chunks); -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ } -void LodePNG_InfoPng_cleanup(LodePNG_InfoPng* info) +void lodepng_info_cleanup(LodePNGInfo* info) { - LodePNG_InfoColor_cleanup(&info->color); + lodepng_color_mode_cleanup(&info->color); #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - LodePNG_Text_cleanup(&info->text); - LodePNG_IText_cleanup(&info->itext); + LodePNGText_cleanup(info); + LodePNGIText_cleanup(info); + + LodePNGUnknownChunks_cleanup(info); #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS - LodePNG_UnknownChunks_cleanup(&info->unknown_chunks); -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ } -unsigned LodePNG_InfoPng_copy(LodePNG_InfoPng* dest, const LodePNG_InfoPng* source) +unsigned lodepng_info_copy(LodePNGInfo* dest, const LodePNGInfo* source) { - unsigned error = 0; - LodePNG_InfoPng_cleanup(dest); + lodepng_info_cleanup(dest); *dest = *source; - LodePNG_InfoColor_init(&dest->color); - error = LodePNG_InfoColor_copy(&dest->color, &source->color); if(error) return error; + lodepng_color_mode_init(&dest->color); + CERROR_TRY_RETURN(lodepng_color_mode_copy(&dest->color, &source->color)); #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - error = LodePNG_Text_copy(&dest->text, &source->text); if(error) return error; - error = LodePNG_IText_copy(&dest->itext, &source->itext); if(error) return error; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + CERROR_TRY_RETURN(LodePNGText_copy(dest, source)); + CERROR_TRY_RETURN(LodePNGIText_copy(dest, source)); -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS - LodePNG_UnknownChunks_init(&dest->unknown_chunks); - error = LodePNG_UnknownChunks_copy(&dest->unknown_chunks, &source->unknown_chunks); if(error) return error; -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ - return error; + LodePNGUnknownChunks_init(dest); + CERROR_TRY_RETURN(LodePNGUnknownChunks_copy(dest, source)); +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + return 0; } -void LodePNG_InfoPng_swap(LodePNG_InfoPng* a, LodePNG_InfoPng* b) +void lodepng_info_swap(LodePNGInfo* a, LodePNGInfo* b) { - LodePNG_InfoPng temp = *a; + LodePNGInfo temp = *a; *a = *b; *b = temp; } -unsigned LodePNG_InfoColor_copy(LodePNG_InfoColor* dest, const LodePNG_InfoColor* source) -{ - size_t i; - LodePNG_InfoColor_cleanup(dest); - *dest = *source; - dest->palette = (unsigned char*)malloc(source->palettesize * 4); - if(!dest->palette && source->palettesize) return 9935; /*alloc fail*/ - for(i = 0; i < source->palettesize * 4; i++) dest->palette[i] = source->palette[i]; - return 0; -} - -void LodePNG_InfoRaw_init(LodePNG_InfoRaw* info) -{ - LodePNG_InfoColor_init(&info->color); -} - -void LodePNG_InfoRaw_cleanup(LodePNG_InfoRaw* info) -{ - LodePNG_InfoColor_cleanup(&info->color); -} - -unsigned LodePNG_InfoRaw_copy(LodePNG_InfoRaw* dest, const LodePNG_InfoRaw* source) -{ - unsigned error = 0; - LodePNG_InfoRaw_cleanup(dest); - *dest = *source; - LodePNG_InfoColor_init(&dest->color); - error = LodePNG_InfoColor_copy(&dest->color, &source->color); - return error; /*this variable could be removed, but it's more clear what is returned this way*/ -} - /* ////////////////////////////////////////////////////////////////////////// */ -/*convert from any color type to RGB or RGBA with 8 bits per sample*/ -static unsigned LodePNG_convert_rgb_a_8(unsigned char* out, const unsigned char* in, - LodePNG_InfoColor* infoIn, size_t numpixels, unsigned bytes, unsigned alpha) +/*index: bitgroup index, bits: bitgroup size(1, 2 or 4, in: bitgroup value, out: octet array to add bits to*/ +static void addColorBits(unsigned char* out, size_t index, unsigned bits, unsigned in) { - size_t i, c, bp = 0; /*bp = bitpointer, used by less-than-8-bit color types*/ - - if(infoIn->bitDepth == 8) - { - switch(infoIn->colorType) - { - case 0: /*greyscale color*/ - for(i = 0; i < numpixels; i++) - { - out[bytes * i + 0] = out[bytes * i + 1] = out[bytes * i + 2] = in[i]; - if(alpha) out[bytes * i + 3] = infoIn->key_defined && in[i] == infoIn->key_r ? 0 : 255; - } - break; - case 2: /*RGB color*/ - for(i = 0; i < numpixels; i++) - { - for(c = 0; c < 3; c++) out[bytes * i + c] = in[3 * i + c]; - if(alpha) - { - if(infoIn->key_defined == 1 && in[3 * i + 0] == infoIn->key_r - && in[3 * i + 1] == infoIn->key_g && in[3 * i + 2] == infoIn->key_b) - out[bytes * i + 3] = 0; - else out[bytes * i + 3] = 255; - } - } - break; - case 3: /*indexed color (palette)*/ - for(i = 0; i < numpixels; i++) - { - if(in[i] >= infoIn->palettesize) return 46; /*invalid palette index*/ - for(c = 0; c < bytes; c++) out[bytes * i + c] = infoIn->palette[4 * in[i] + c]; - } - break; - case 4: /*greyscale with alpha*/ - for(i = 0; i < numpixels; i++) - { - out[bytes * i + 0] = out[bytes * i + 1] = out[bytes * i + 2] = in[2 * i + 0]; - if(alpha) out[bytes * i + 3] = in[2 * i + 1]; - } - break; - case 6: /*RGB with alpha*/ - for(i = 0; i < numpixels; i++) - { - for(c = 0; c < bytes; c++) out[bytes * i + c] = in[4 * i + c]; - } - break; - default: break; - } - } - else if(infoIn->bitDepth == 16) - { - switch(infoIn->colorType) - { - case 0: /*greyscale color*/ - for(i = 0; i < numpixels; i++) - { - out[bytes * i + 0] = out[bytes * i + 1] = out[bytes * i + 2] = in[2 * i]; - if(alpha) out[bytes * i + 3] = infoIn->key_defined && 256U * in[i] + in[i + 1] == infoIn->key_r ? 0 : 255; - } - break; - case 2: /*RGB color*/ - for(i = 0; i < numpixels; i++) - { - if(alpha) out[bytes * i + 3] = 255; - for(c = 0; c < 3; c++) out[bytes * i + c] = in[6 * i + 2 * c]; - if(alpha) - { - if(infoIn->key_defined && 256U * in[6 * i + 0] + in[6 * i + 1] == infoIn->key_r - && 256U * in[6 * i + 2] + in[6 * i + 3] == infoIn->key_g - && 256U * in[6 * i + 4] + in[6 * i + 5] == infoIn->key_b) - out[bytes * i + 3] = 0; - else out[bytes * i + 3] = 255; - } - } - break; - case 4: /*greyscale with alpha*/ - for(i = 0; i < numpixels; i++) - { - out[bytes * i + 0] = out[bytes * i + 1] = out[bytes * i + 2] = in[4 * i]; - if(alpha) out[bytes * i + 3] = in[4 * i + 2]; - } - break; - case 6: /*RGB with alpha*/ - for(i = 0; i < numpixels; i++) - { - for(c = 0; c < bytes; c++) out[bytes * i + c] = in[8 * i + 2 * c]; - } - break; - default: break; - } - } - else /*infoIn->bitDepth is less than 8 bit per channel*/ - { - switch(infoIn->colorType) - { - case 0: /*greyscale color*/ - for(i = 0; i < numpixels; i++) - { - unsigned value = readBitsFromReversedStream(&bp, in, infoIn->bitDepth); - unsigned highest = ((1U << infoIn->bitDepth) - 1U); /*highest possible value for this bit depth*/ - /*scale value from 0 to 255*/ - out[bytes * i + 0] = out[bytes * i + 1] = out[bytes * i + 2] - = (unsigned char)((value * 255) / highest); - if(alpha) out[bytes * i + 3] = infoIn->key_defined && value == infoIn->key_r ? 0 : 255; - } - break; - case 3: /*indexed color (palette)*/ - for(i = 0; i < numpixels; i++) - { - unsigned value = readBitsFromReversedStream(&bp, in, infoIn->bitDepth); - if(value >= infoIn->palettesize) return 47; - for(c = 0; c < bytes; c++) out[bytes * i + c] = infoIn->palette[4 * value + c]; - } - break; - default: break; - } - } - return 0; + /*p = the partial index in the byte, e.g. with 4 palettebits it is 0 for first half or 1 for second half*/ + unsigned p = index % (8 / bits); + in &= (1 << bits) - 1; /*filter out any other bits of the input value*/ + in = in << (bits * (8 / bits - p - 1)); + if(p == 0) out[index * bits / 8] = in; + else out[index * bits / 8] |= in; } -/*convert from any greyscale color type to 8-bit greyscale with or without alpha channel*/ -static unsigned LodePNG_convert_grey_8(unsigned char* out, const unsigned char* in, - LodePNG_InfoColor* infoIn, size_t numpixels, unsigned bytes, unsigned alpha) -{ - size_t i, bp = 0; /*bp = bitpointer, used by less-than-8-bit color types*/ +typedef struct ColorTree ColorTree; - if(infoIn->bitDepth == 8) +/* +One node of a color tree +This is the data structure used to count the number of unique colors and to get a palette +index for a color. It's like an octree, but because the alpha channel is used too, each +node has 16 instead of 8 children. +*/ +struct ColorTree +{ + ColorTree* children[16]; /*up to 16 pointers to ColorTree of next level*/ + int index; /*the payload. Only has a meaningful value if this is in the last level*/ +}; + +static void color_tree_init(ColorTree* tree) +{ + int i; + for(i = 0; i < 16; i++) tree->children[i] = 0; + tree->index = -1; +} + +static void color_tree_cleanup(ColorTree* tree) +{ + int i; + for(i = 0; i < 16; i++) { - switch(infoIn->colorType) + if(tree->children[i]) { - case 0: /*greyscale color*/ - for(i = 0; i < numpixels; i++) - { - out[bytes * i] = in[i]; - if(alpha) out[bytes * i + 1] = infoIn->key_defined && in[i] == infoIn->key_r ? 0 : 255; - } - break; - case 4: /*greyscale with alpha*/ - for(i = 0; i < numpixels; i++) - { - out[bytes * i + 0] = in[2 * i + 0]; - if(alpha) out[bytes * i + 1] = in[2 * i + 1]; - } - break; - default: return 31; + color_tree_cleanup(tree->children[i]); + myfree(tree->children[i]); } } - else if(infoIn->bitDepth == 16) +} + +/*returns -1 if color not present, its index otherwise*/ +static int color_tree_get(ColorTree* tree, unsigned char r, unsigned char g, unsigned char b, unsigned char a) +{ + int bit = 0; + for(bit = 0; bit < 8; bit++) { - switch(infoIn->colorType) + int i = 8 * ((r >> bit) & 1) + 4 * ((g >> bit) & 1) + 2 * ((b >> bit) & 1) + 1 * ((a >> bit) & 1); + if(!tree->children[i]) return -1; + else tree = tree->children[i]; + } + return tree ? tree->index : -1; +} + +#ifdef LODEPNG_COMPILE_ENCODER +static int color_tree_has(ColorTree* tree, unsigned char r, unsigned char g, unsigned char b, unsigned char a) +{ + return color_tree_get(tree, r, g, b, a) >= 0; +} +#endif /*LODEPNG_COMPILE_ENCODER*/ + +/*color is not allowed to already exist. +Index should be >= 0 (it's signed to be compatible with using -1 for "doesn't exist")*/ +static void color_tree_add(ColorTree* tree, + unsigned char r, unsigned char g, unsigned char b, unsigned char a, int index) +{ + int bit; + for(bit = 0; bit < 8; bit++) + { + int i = 8 * ((r >> bit) & 1) + 4 * ((g >> bit) & 1) + 2 * ((b >> bit) & 1) + 1 * ((a >> bit) & 1); + if(!tree->children[i]) { - case 0: /*greyscale color*/ - for(i = 0; i < numpixels; i++) - { - if(alpha) out[bytes * i + 1] = 255; - out[bytes * i] = in[2 * i]; - if(alpha && infoIn->key_defined && 256U * in[i] + in[i + 1] == infoIn->key_r) - { - out[bytes * i + 1] = 0; - } - } - break; - case 4: /*greyscale with alpha*/ - for(i = 0; i < numpixels; i++) - { - out[bytes * i] = in[4 * i]; /*most significant byte*/ - if(alpha) out[bytes * i + 1] = in[4 * i + 2]; /*most significant byte*/ - } - break; - default: return 31; + tree->children[i] = (ColorTree*)mymalloc(sizeof(ColorTree)); + color_tree_init(tree->children[i]); + } + tree = tree->children[i]; + } + tree->index = index; +} + +/*put a pixel, given its RGBA color, into image of any color type*/ +static unsigned rgba8ToPixel(unsigned char* out, size_t i, + const LodePNGColorMode* mode, ColorTree* tree /*for palette*/, + unsigned char r, unsigned char g, unsigned char b, unsigned char a) +{ + if(mode->colortype == LCT_GREY) + { + unsigned char grey = r; /*((unsigned short)r + g + b) / 3*/; + if(mode->bitdepth == 8) out[i] = grey; + else if(mode->bitdepth == 16) out[i * 2 + 0] = out[i * 2 + 1] = grey; + else + { + /*take the most significant bits of grey*/ + grey = (grey >> (8 - mode->bitdepth)) & ((1 << mode->bitdepth) - 1); + addColorBits(out, i, mode->bitdepth, grey); } } - else /*infoIn->bitDepth is less than 8 bit per channel*/ + else if(mode->colortype == LCT_RGB) { - if(infoIn->colorType != 0) return 31; /*colorType 0 is the only greyscale type with < 8 bits per channel*/ - for(i = 0; i < numpixels; i++) + if(mode->bitdepth == 8) { - unsigned value = readBitsFromReversedStream(&bp, in, infoIn->bitDepth); - unsigned highest = ((1U << infoIn->bitDepth) - 1U); /*highest possible value for this bit depth*/ - out[bytes * i] = (unsigned char)((value * 255) / highest); /*scale value from 0 to 255*/ - if(alpha) + out[i * 3 + 0] = r; + out[i * 3 + 1] = g; + out[i * 3 + 2] = b; + } + else + { + out[i * 6 + 0] = out[i * 6 + 1] = r; + out[i * 6 + 2] = out[i * 6 + 3] = g; + out[i * 6 + 4] = out[i * 6 + 5] = b; + } + } + else if(mode->colortype == LCT_PALETTE) + { + int index = color_tree_get(tree, r, g, b, a); + if(index < 0) return 82; /*color not in palette*/ + if(mode->bitdepth == 8) out[i] = index; + else addColorBits(out, i, mode->bitdepth, index); + } + else if(mode->colortype == LCT_GREY_ALPHA) + { + unsigned char grey = r; /*((unsigned short)r + g + b) / 3*/; + if(mode->bitdepth == 8) + { + out[i * 2 + 0] = grey; + out[i * 2 + 1] = a; + } + else if(mode->bitdepth == 16) + { + out[i * 4 + 0] = out[i * 4 + 1] = grey; + out[i * 4 + 2] = out[i * 4 + 3] = a; + } + } + else if(mode->colortype == LCT_RGBA) + { + if(mode->bitdepth == 8) + { + out[i * 4 + 0] = r; + out[i * 4 + 1] = g; + out[i * 4 + 2] = b; + out[i * 4 + 3] = a; + } + else + { + out[i * 8 + 0] = out[i * 8 + 1] = r; + out[i * 8 + 2] = out[i * 8 + 3] = g; + out[i * 8 + 4] = out[i * 8 + 5] = b; + out[i * 8 + 6] = out[i * 8 + 7] = a; + } + } + + return 0; /*no error*/ +} + +/*put a pixel, given its RGBA16 color, into image of any color 16-bitdepth type*/ +static unsigned rgba16ToPixel(unsigned char* out, size_t i, + const LodePNGColorMode* mode, + unsigned short r, unsigned short g, unsigned short b, unsigned short a) +{ + if(mode->bitdepth != 16) return 85; /*must be 16 for this function*/ + if(mode->colortype == LCT_GREY) + { + unsigned short grey = r; /*((unsigned)r + g + b) / 3*/; + out[i * 2 + 0] = (grey >> 8) & 255; + out[i * 2 + 1] = grey & 255; + } + else if(mode->colortype == LCT_RGB) + { + out[i * 6 + 0] = (r >> 8) & 255; + out[i * 6 + 1] = r & 255; + out[i * 6 + 2] = (g >> 8) & 255; + out[i * 6 + 3] = g & 255; + out[i * 6 + 4] = (b >> 8) & 255; + out[i * 6 + 5] = b & 255; + } + else if(mode->colortype == LCT_GREY_ALPHA) + { + unsigned short grey = r; /*((unsigned)r + g + b) / 3*/; + out[i * 4 + 0] = (grey >> 8) & 255; + out[i * 4 + 1] = grey & 255; + out[i * 4 + 2] = (a >> 8) & 255; + out[i * 4 + 3] = a & 255; + } + else if(mode->colortype == LCT_RGBA) + { + out[i * 8 + 0] = (r >> 8) & 255; + out[i * 8 + 1] = r & 255; + out[i * 8 + 2] = (g >> 8) & 255; + out[i * 8 + 3] = g & 255; + out[i * 8 + 4] = (b >> 8) & 255; + out[i * 8 + 5] = b & 255; + out[i * 8 + 6] = (a >> 8) & 255; + out[i * 8 + 7] = a & 255; + } + + return 0; /*no error*/ +} + +/*Get RGBA8 color of pixel with index i (y * width + x) from the raw image with given color type.*/ +static unsigned getPixelColorRGBA8(unsigned char* r, unsigned char* g, + unsigned char* b, unsigned char* a, + const unsigned char* in, size_t i, + const LodePNGColorMode* mode) +{ + if(mode->colortype == LCT_GREY) + { + if(mode->bitdepth == 8) + { + *r = *g = *b = in[i]; + if(mode->key_defined && *r == mode->key_r) *a = 0; + else *a = 255; + } + else if(mode->bitdepth == 16) + { + *r = *g = *b = in[i * 2 + 0]; + if(mode->key_defined && 256U * in[i * 2 + 0] + in[i * 2 + 1] == mode->key_r) *a = 0; + else *a = 255; + } + else + { + unsigned highest = ((1U << mode->bitdepth) - 1U); /*highest possible value for this bit depth*/ + size_t j = i * mode->bitdepth; + unsigned value = readBitsFromReversedStream(&j, in, mode->bitdepth); + *r = *g = *b = (value * 255) / highest; + if(mode->key_defined && value == mode->key_r) *a = 0; + else *a = 255; + } + } + else if(mode->colortype == LCT_RGB) + { + if(mode->bitdepth == 8) + { + *r = in[i * 3 + 0]; *g = in[i * 3 + 1]; *b = in[i * 3 + 2]; + if(mode->key_defined && *r == mode->key_r && *g == mode->key_g && *b == mode->key_b) *a = 0; + else *a = 255; + } + else + { + *r = in[i * 6 + 0]; + *g = in[i * 6 + 2]; + *b = in[i * 6 + 4]; + if(mode->key_defined && 256U * in[i * 6 + 0] + in[i * 6 + 1] == mode->key_r + && 256U * in[i * 6 + 2] + in[i * 6 + 3] == mode->key_g + && 256U * in[i * 6 + 4] + in[i * 6 + 5] == mode->key_b) *a = 0; + else *a = 255; + } + } + else if(mode->colortype == LCT_PALETTE) + { + unsigned index; + if(mode->bitdepth == 8) index = in[i]; + else + { + size_t j = i * mode->bitdepth; + index = readBitsFromReversedStream(&j, in, mode->bitdepth); + } + if(index >= mode->palettesize) return 47; /*index out of palette*/ + *r = mode->palette[index * 4 + 0]; + *g = mode->palette[index * 4 + 1]; + *b = mode->palette[index * 4 + 2]; + *a = mode->palette[index * 4 + 3]; + } + else if(mode->colortype == LCT_GREY_ALPHA) + { + if(mode->bitdepth == 8) + { + *r = *g = *b = in[i * 2 + 0]; + *a = in[i * 2 + 1]; + } + else + { + *r = *g = *b = in[i * 4 + 0]; + *a = in[i * 4 + 2]; + } + } + else if(mode->colortype == LCT_RGBA) + { + if(mode->bitdepth == 8) + { + *r = in[i * 4 + 0]; + *g = in[i * 4 + 1]; + *b = in[i * 4 + 2]; + *a = in[i * 4 + 3]; + } + else + { + *r = in[i * 8 + 0]; + *g = in[i * 8 + 2]; + *b = in[i * 8 + 4]; + *a = in[i * 8 + 6]; + } + } + + return 0; /*no error*/ +} + +/*Similar to getPixelColorRGBA8, but with all the for loops inside of the color +mode test cases, optimized to convert the colors much faster, when converting +to RGBA or RGB with 8 bit per cannel. buffer must be RGBA or RGB output with +enough memory, if has_alpha is true the output is RGBA. mode has the color mode +of the input buffer.*/ +static unsigned getPixelColorsRGBA8(unsigned char* buffer, size_t numpixels, + unsigned has_alpha, const unsigned char* in, + const LodePNGColorMode* mode) +{ + unsigned num_channels = has_alpha ? 4 : 3; + size_t i; + if(mode->colortype == LCT_GREY) + { + if(mode->bitdepth == 8) + { + for(i = 0; i < numpixels; i++, buffer += num_channels) { - if(infoIn->key_defined && value == infoIn->key_r) out[bytes * i + 1] = 0; - else out[bytes * i + 1] = 255; + buffer[0] = buffer[1] = buffer[2] = in[i]; + if(has_alpha) buffer[3] = mode->key_defined && in[i] == mode->key_r ? 0 : 255; + } + } + else if(mode->bitdepth == 16) + { + for(i = 0; i < numpixels; i++, buffer += num_channels) + { + buffer[0] = buffer[1] = buffer[2] = in[i * 2]; + if(has_alpha) buffer[3] = mode->key_defined && 256U * in[i * 2 + 0] + in[i * 2 + 1] == mode->key_r ? 0 : 255; + } + } + else + { + unsigned highest = ((1U << mode->bitdepth) - 1U); /*highest possible value for this bit depth*/ + size_t j = 0; + for(i = 0; i < numpixels; i++, buffer += num_channels) + { + unsigned value = readBitsFromReversedStream(&j, in, mode->bitdepth); + buffer[0] = buffer[1] = buffer[2] = (value * 255) / highest; + if(has_alpha) buffer[3] = mode->key_defined && value == mode->key_r ? 0 : 255; } } } - return 0; -} - -/*convert from any color type to RGB or RGBA with 8 bits per sample*/ -static unsigned LodePNG_convert_rgb_a_16(unsigned char* out, const unsigned char* in, - LodePNG_InfoColor* infoIn, size_t numpixels, unsigned bytes, unsigned alpha) -{ - size_t i, c, bp = 0; /*bp = bitpointer, used by less-than-8-bit color types*/ - - if(infoIn->bitDepth == 8) + else if(mode->colortype == LCT_RGB) { - switch(infoIn->colorType) + if(mode->bitdepth == 8) { - case 0: /*greyscale color*/ - for(i = 0; i < numpixels; i++) - { - out[bytes * i + 0] = out[bytes * i + 2] = out[bytes * i + 4] = in[i]; - out[bytes * i + 1] = out[bytes * i + 3] = out[bytes * i + 5] = in[i]; - if(alpha) - { - if(alpha && infoIn->key_defined && in[i] == infoIn->key_r) out[bytes * i + 6] = out[bytes * i + 7] = 0; - else out[bytes * i + 6] = out[bytes * i + 7] = 255; - } - } - break; - case 2: /*RGB color*/ - for(i = 0; i < numpixels; i++) - { - out[bytes * i + 0] = out[bytes * i + 1] = in[3 * i + 0]; - out[bytes * i + 2] = out[bytes * i + 3] = in[3 * i + 1]; - out[bytes * i + 4] = out[bytes * i + 5] = in[3 * i + 2]; - if(alpha) - { - if(infoIn->key_defined == 1 && in[3 * i + 0] == infoIn->key_r - && in[3 * i + 1] == infoIn->key_g && in[3 * i + 2] == infoIn->key_b) - out[bytes * i + 6] = out[bytes * i + 7] = 0; - else out[bytes * i + 6] = out[bytes * i + 7] = 255; - } - } - break; - case 3: /*indexed color (palette)*/ - for(i = 0; i < numpixels; i++) - { - if(in[i] >= infoIn->palettesize) return 46; /*invalid palette index*/ - for(c = 0; c < bytes; c++) - { - out[bytes * i + 2 * c] = out[bytes * i + 2 * c + 1] = infoIn->palette[4 * in[i] + c]; - } - } - break; - case 4: /*greyscale with alpha*/ - for(i = 0; i < numpixels; i++) - { - out[bytes * i + 0] = out[bytes * i + 2] = out[bytes * i + 4] = in[i]; - out[bytes * i + 1] = out[bytes * i + 3] = out[bytes * i + 5] = in[i]; - if(alpha) - { - out[bytes * i + 6] = out[bytes * i + 7] = in[2 * i + 1]; - } - } - break; - case 6: /*RGB with alpha*/ - for(i = 0; i < numpixels; i++) - { - for(c = 0; c < 3; c++) - { - out[bytes * i + 2 * c] = out[bytes * i + 2 * c + 1] = in[4 * i + c]; - } - if(alpha) - { - out[bytes * i + 6] = out[bytes * i + 7] = in[4 * i + c]; - } - } - break; - default: break; - } - } - else if(infoIn->bitDepth == 16) - { - switch(infoIn->colorType) - { - case 0: /*greyscale color*/ - for(i = 0; i < numpixels; i++) - { - out[bytes * i + 0] = out[bytes * i + 2] = out[bytes * i + 4] = in[2 * i]; - out[bytes * i + 1] = out[bytes * i + 3] = out[bytes * i + 5] = in[2 * i + 1]; - if(alpha) - { - if(infoIn->key_defined && 256U * in[i] + in[i + 1] == infoIn->key_r) - out[bytes * i + 6] = out[bytes * i + 7] = 0; - else out[bytes * i + 6] = out[bytes * i + 7] = 255; - } - } - break; - case 2: /*RGB color*/ - for(i = 0; i < numpixels; i++) - { - for(c = 0; c < 6; c++) out[bytes * i + c] = in[6 * i + c]; - if(alpha) - { - if(infoIn->key_defined && 256U * in[6 * i + 0] + in[6 * i + 1] == infoIn->key_r - && 256U * in[6 * i + 2] + in[6 * i + 3] == infoIn->key_g - && 256U * in[6 * i + 4] + in[6 * i + 5] == infoIn->key_b) - out[bytes * i + 6] = out[bytes * i + 7] = 0; - else out[bytes * i + 6] = out[bytes * i + 7] = 255; - } - } - break; - case 4: /*greyscale with alpha*/ - for(i = 0; i < numpixels; i++) - { - out[bytes * i + 0] = out[bytes * i + 2] = out[bytes * i + 4] = in[4 * i + 0]; - out[bytes * i + 1] = out[bytes * i + 3] = out[bytes * i + 5] = in[4 * i + 1]; - if(alpha) - { - out[bytes * i + 6] = in[4 * i + 2]; - out[bytes * i + 7] = in[4 * i + 3]; - } - } - break; - case 6: /*RGB with alpha*/ - for(i = 0; i < numpixels; i++) - { - for(c = 0; c < bytes; c++) out[bytes * i + c] = in[8 * i + 2 * c]; - } - break; - default: break; - } - } - else /*infoIn->bitDepth is less than 8 bit per channel*/ - { - switch(infoIn->colorType) - { - case 0: /*greyscale color*/ - for(i = 0; i < numpixels; i++) - { - unsigned value = readBitsFromReversedStream(&bp, in, infoIn->bitDepth); - unsigned highest = ((1U << infoIn->bitDepth) - 1U); /*highest possible value for this bit depth*/ - /*scale value from 0 to 255*/ - out[bytes * i + 0] = out[bytes * i + 2] = out[bytes * i + 4] - = out[bytes * i + 1] = out[bytes * i + 3] - = out[bytes * i + 5] = (unsigned char)((value * 255) / highest); - if(alpha) - { - if(infoIn->key_defined && value == infoIn->key_r) out[bytes * i + 6] = out[bytes * i + 7] = 0; - else out[bytes * i + 6] = out[bytes * i + 7] = 255; - } - } - break; - case 3: /*indexed color (palette)*/ - for(i = 0; i < numpixels; i++) - { - unsigned value = readBitsFromReversedStream(&bp, in, infoIn->bitDepth); - if(value >= infoIn->palettesize) return 47; - for(c = 0; c < bytes / 2; c++) - { - out[bytes * i + c * 2 + 0] = out[bytes * i + c * 2 + 1] = infoIn->palette[4 * value + c]; - } - } - break; - default: break; - } - } - return 0; -} - -/*convert from any greyscale color type to 16-bit greyscale with or without alpha channel*/ -static unsigned LodePNG_convert_grey_16(unsigned char* out, const unsigned char* in, - LodePNG_InfoColor* infoIn, size_t numpixels, unsigned bytes, unsigned alpha) -{ - size_t i, c, bp = 0; /*bp = bitpointer, used by less-than-8-bit color types*/ - - if(infoIn->bitDepth == 8) - { - switch(infoIn->colorType) - { - case 0: /*greyscale color*/ - for(i = 0; i < numpixels; i++) - { - out[bytes * i] = out[bytes * i + 1] = in[i]; - if(alpha) - { - if(infoIn->key_defined && in[i] == infoIn->key_r) out[bytes * i + 2] = out[bytes * i + 3] = 0; - else out[bytes * i + 2] = out[bytes * i + 3] = 255; - } - } - break; - case 4: /*greyscale with alpha*/ - for(i = 0; i < numpixels; i++) - { - out[bytes * i + 0] = out[bytes * i + 1] = in[2 * i + 0]; - if(alpha) out[bytes * i + 2] = out[bytes * i + 3] = in[2 * i + 1]; - } - break; - default: return 31; - } - } - else if(infoIn->bitDepth == 16) - { - switch(infoIn->colorType) - { - case 0: /*greyscale color*/ - for(i = 0; i < numpixels; i++) - { - out[bytes * i + 0] = in[2 * i + 0]; - out[bytes * i + 1] = in[2 * i + 1]; - if(alpha) - { - if(infoIn->key_defined && 256U * in[i] + in[i + 1] == infoIn->key_r) - out[bytes * i + 2] = out[bytes * i + 3] = 0; - else out[bytes * i + 2] = out[bytes * i + 3] = 255; - } - } - break; - case 4: /*greyscale with alpha*/ - for(i = 0; i < numpixels; i++) - { - for(c = 0; c < bytes; c++) out[bytes * i + c] = in[4 * i + c]; - } - break; - default: return 31; - } - } - else /*infoIn->bitDepth is less than 8 bit per channel*/ - { - if(infoIn->colorType != 0) return 31; /*colorType 0 is the only greyscale type with < 8 bits per channel*/ - for(i = 0; i < numpixels; i++) - { - unsigned value = readBitsFromReversedStream(&bp, in, infoIn->bitDepth); - unsigned highest = ((1U << infoIn->bitDepth) - 1U); /*highest possible value for this bit depth*/ - out[bytes * i] = out[bytes * i + 1] = (unsigned char)((value * 255) / highest); /*scale value from 0 to 255*/ - if(alpha) + for(i = 0; i < numpixels; i++, buffer += num_channels) { - if(infoIn->key_defined && value == infoIn->key_r) out[bytes * i + 2] = out[bytes * i + 3] = 0; - else out[bytes * i + 2] = out[bytes * i + 3] = 255; + buffer[0] = in[i * 3 + 0]; + buffer[1] = in[i * 3 + 1]; + buffer[2] = in[i * 3 + 2]; + if(has_alpha) buffer[3] = mode->key_defined && buffer[0] == mode->key_r + && buffer[1]== mode->key_g && buffer[2] == mode->key_b ? 0 : 255; + } + } + else + { + for(i = 0; i < numpixels; i++, buffer += num_channels) + { + buffer[0] = in[i * 6 + 0]; + buffer[1] = in[i * 6 + 2]; + buffer[2] = in[i * 6 + 4]; + if(has_alpha) buffer[3] = mode->key_defined + && 256U * in[i * 6 + 0] + in[i * 6 + 1] == mode->key_r + && 256U * in[i * 6 + 2] + in[i * 6 + 3] == mode->key_g + && 256U * in[i * 6 + 4] + in[i * 6 + 5] == mode->key_b ? 0 : 255; } } } - return 0; + else if(mode->colortype == LCT_PALETTE) + { + unsigned index; + size_t j = 0; + for(i = 0; i < numpixels; i++, buffer += num_channels) + { + if(mode->bitdepth == 8) index = in[i]; + else index = readBitsFromReversedStream(&j, in, mode->bitdepth); + if(index >= mode->palettesize) return 47; /*index out of palette*/ + buffer[0] = mode->palette[index * 4 + 0]; + buffer[1] = mode->palette[index * 4 + 1]; + buffer[2] = mode->palette[index * 4 + 2]; + if(has_alpha) buffer[3] = mode->palette[index * 4 + 3]; + } + } + else if(mode->colortype == LCT_GREY_ALPHA) + { + if(mode->bitdepth == 8) + { + for(i = 0; i < numpixels; i++, buffer += num_channels) + { + buffer[0] = buffer[1] = buffer[2] = in[i * 2 + 0]; + if(has_alpha) buffer[3] = in[i * 2 + 1]; + } + } + else + { + for(i = 0; i < numpixels; i++, buffer += num_channels) + { + buffer[0] = buffer[1] = buffer[2] = in[i * 4 + 0]; + if(has_alpha) buffer[3] = in[i * 4 + 2]; + } + } + } + else if(mode->colortype == LCT_RGBA) + { + if(mode->bitdepth == 8) + { + for(i = 0; i < numpixels; i++, buffer += num_channels) + { + buffer[0] = in[i * 4 + 0]; + buffer[1] = in[i * 4 + 1]; + buffer[2] = in[i * 4 + 2]; + if(has_alpha) buffer[3] = in[i * 4 + 3]; + } + } + else + { + for(i = 0; i < numpixels; i++, buffer += num_channels) + { + buffer[0] = in[i * 8 + 0]; + buffer[1] = in[i * 8 + 2]; + buffer[2] = in[i * 8 + 4]; + if(has_alpha) buffer[3] = in[i * 8 + 6]; + } + } + } + + return 0; /*no error*/ +} + +/*Get RGBA16 color of pixel with index i (y * width + x) from the raw image with +given color type, but the given color type must be 16-bit itself.*/ +static unsigned getPixelColorRGBA16(unsigned short* r, unsigned short* g, unsigned short* b, unsigned short* a, + const unsigned char* in, size_t i, const LodePNGColorMode* mode) +{ + if(mode->bitdepth != 16) return 85; /*error: this function only supports 16-bit input*/ + + if(mode->colortype == LCT_GREY) + { + *r = *g = *b = 256 * in[i * 2 + 0] + in[i * 2 + 1]; + if(mode->key_defined && 256U * in[i * 2 + 0] + in[i * 2 + 1] == mode->key_r) *a = 0; + else *a = 65535; + } + else if(mode->colortype == LCT_RGB) + { + *r = 256 * in[i * 6 + 0] + in[i * 6 + 1]; + *g = 256 * in[i * 6 + 2] + in[i * 6 + 3]; + *b = 256 * in[i * 6 + 4] + in[i * 6 + 5]; + if(mode->key_defined && 256U * in[i * 6 + 0] + in[i * 6 + 1] == mode->key_r + && 256U * in[i * 6 + 2] + in[i * 6 + 3] == mode->key_g + && 256U * in[i * 6 + 4] + in[i * 6 + 5] == mode->key_b) *a = 0; + else *a = 65535; + } + else if(mode->colortype == LCT_GREY_ALPHA) + { + *r = *g = *b = 256 * in[i * 4 + 0] + in[i * 4 + 1]; + *a = 256 * in[i * 4 + 2] + in[i * 4 + 3]; + } + else if(mode->colortype == LCT_RGBA) + { + *r = 256 * in[i * 8 + 0] + in[i * 8 + 1]; + *g = 256 * in[i * 8 + 2] + in[i * 8 + 3]; + *b = 256 * in[i * 8 + 4] + in[i * 8 + 5]; + *a = 256 * in[i * 8 + 6] + in[i * 8 + 7]; + } + else return 85; /*error: this function only supports 16-bit input, not palettes*/ + + return 0; /*no error*/ } /* converts from any color type to 24-bit or 32-bit (later maybe more supported). return value = LodePNG error code the out buffer must have (w * h * bpp + 7) / 8 bytes, where bpp is the bits per pixel of the output color type -(LodePNG_InfoColor_getBpp) for < 8 bpp images, there may _not_ be padding bits at the end of scanlines. +(lodepng_get_bpp) for < 8 bpp images, there may _not_ be padding bits at the end of scanlines. */ -unsigned LodePNG_convert(unsigned char* out, const unsigned char* in, LodePNG_InfoColor* infoOut, - LodePNG_InfoColor* infoIn, unsigned w, unsigned h) +unsigned lodepng_convert(unsigned char* out, const unsigned char* in, + LodePNGColorMode* mode_out, LodePNGColorMode* mode_in, + unsigned w, unsigned h) { - size_t numpixels = w * h; /*amount of pixels*/ - unsigned bytes = LodePNG_InfoColor_getBpp(infoOut) / 8; /*bytes per pixel in the output image*/ - unsigned alpha = LodePNG_InfoColor_isAlphaType(infoOut); /*use 8-bit alpha channel*/ - - /*cases where in and out already have the same format*/ - if(LodePNG_InfoColor_equal(infoIn, infoOut)) + unsigned error = 0; + size_t i; + ColorTree tree; + size_t numpixels = w * h; + + if(lodepng_color_mode_equal(mode_out, mode_in)) { - size_t i; - size_t size = (numpixels * LodePNG_InfoColor_getBpp(infoIn) + 7) / 8; - for(i = 0; i < size; i++) out[i] = in[i]; - return 0; + size_t numbytes = lodepng_get_raw_size(w, h, mode_in); + for(i = 0; i < numbytes; i++) out[i] = in[i]; + return error; } - else if((infoOut->colorType == 2 || infoOut->colorType == 6) && infoOut->bitDepth == 8) + + if(mode_out->colortype == LCT_PALETTE) { - LodePNG_convert_rgb_a_8(out, in, infoIn, numpixels, bytes, alpha); + size_t palsize = 1 << mode_out->bitdepth; + if(mode_out->palettesize < palsize) palsize = mode_out->palettesize; + color_tree_init(&tree); + for(i = 0; i < palsize; i++) + { + unsigned char* p = &mode_out->palette[i * 4]; + color_tree_add(&tree, p[0], p[1], p[2], p[3], i); + } } - else if(LodePNG_InfoColor_isGreyscaleType(infoOut) && infoOut->bitDepth == 8) + + if(mode_in->bitdepth == 16 && mode_out->bitdepth == 16) { - /*conversion from greyscale to greyscale*/ - if(!LodePNG_InfoColor_isGreyscaleType(infoIn)) return 62; /*converting from color to grey is not supported*/ - LodePNG_convert_grey_8(out, in, infoIn, numpixels, bytes, alpha); + for(i = 0; i < numpixels; i++) + { + unsigned short r = 0, g = 0, b = 0, a = 0; + error = getPixelColorRGBA16(&r, &g, &b, &a, in, i, mode_in); + if(error) break; + error = rgba16ToPixel(out, i, mode_out, r, g, b, a); + if(error) break; + } } - else if((infoOut->colorType == 2 || infoOut->colorType == 6) && infoOut->bitDepth == 16) + else if(mode_out->bitdepth == 8 && mode_out->colortype == LCT_RGBA) { - LodePNG_convert_rgb_a_16(out, in, infoIn, numpixels, bytes, alpha); + error = getPixelColorsRGBA8(out, numpixels, 1, in, mode_in); } - else if(LodePNG_InfoColor_isGreyscaleType(infoOut) && infoOut->bitDepth == 16) + else if(mode_out->bitdepth == 8 && mode_out->colortype == LCT_RGB) { - /*conversion from greyscale to greyscale*/ - if(!LodePNG_InfoColor_isGreyscaleType(infoIn)) return 62; /*converting from color to grey is not supported*/ - LodePNG_convert_grey_16(out, in, infoIn, numpixels, bytes, alpha); + error = getPixelColorsRGBA8(out, numpixels, 0, in, mode_in); } - else return 59; /*invalid color mode*/ - return 0; + else + { + unsigned char r = 0, g = 0, b = 0, a = 0; + for(i = 0; i < numpixels; i++) + { + error = getPixelColorRGBA8(&r, &g, &b, &a, in, i, mode_in); + if(error) break; + error = rgba8ToPixel(out, i, mode_out, &tree, r, g, b, a); + if(error) break; + } + } + + if(mode_out->colortype == LCT_PALETTE) + { + color_tree_cleanup(&tree); + } + + return error; } +#ifdef LODEPNG_COMPILE_ENCODER + +typedef struct ColorProfile +{ + unsigned char sixteenbit; /*needs more than 8 bits per channel*/ + unsigned char sixteenbit_done; + + + unsigned char colored; /*not greyscale*/ + unsigned char colored_done; + + unsigned char key; /*a color key is required, or more*/ + unsigned short key_r; /*these values are always in 16-bit bitdepth in the profile*/ + unsigned short key_g; + unsigned short key_b; + unsigned char alpha; /*alpha channel, or alpha palette, required*/ + unsigned char alpha_done; + + unsigned numcolors; + ColorTree tree; /*for listing the counted colors, up to 256*/ + unsigned char* palette; /*size 1024. Remember up to the first 256 RGBA colors*/ + unsigned maxnumcolors; /*if more than that amount counted*/ + unsigned char numcolors_done; + + unsigned greybits; /*amount of bits required for greyscale (1, 2, 4, 8). Does not take 16 bit into account.*/ + unsigned char greybits_done; + +} ColorProfile; + +static void color_profile_init(ColorProfile* profile, LodePNGColorMode* mode) +{ + profile->sixteenbit = 0; + profile->sixteenbit_done = mode->bitdepth == 16 ? 0 : 1; + + profile->colored = 0; + profile->colored_done = lodepng_is_greyscale_type(mode) ? 1 : 0; + + profile->key = 0; + profile->alpha = 0; + profile->alpha_done = lodepng_can_have_alpha(mode) ? 0 : 1; + + profile->numcolors = 0; + color_tree_init(&profile->tree); + profile->palette = (unsigned char*)mymalloc(1024); + profile->maxnumcolors = 257; + if(lodepng_get_bpp(mode) <= 8) + { + int bpp = lodepng_get_bpp(mode); + profile->maxnumcolors = bpp == 1 ? 2 : (bpp == 2 ? 4 : (bpp == 4 ? 16 : 256)); + } + profile->numcolors_done = 0; + + profile->greybits = 1; + profile->greybits_done = lodepng_get_bpp(mode) == 1 ? 1 : 0; +} + +static void color_profile_cleanup(ColorProfile* profile) +{ + color_tree_cleanup(&profile->tree); + myfree(profile->palette); +} + +/*function used for debug purposes with C++*/ +/*void printColorProfile(ColorProfile* p) +{ + std::cout << "sixteenbit: " << (int)p->sixteenbit << std::endl; + std::cout << "sixteenbit_done: " << (int)p->sixteenbit_done << std::endl; + std::cout << "colored: " << (int)p->colored << std::endl; + std::cout << "colored_done: " << (int)p->colored_done << std::endl; + std::cout << "key: " << (int)p->key << std::endl; + std::cout << "key_r: " << (int)p->key_r << std::endl; + std::cout << "key_g: " << (int)p->key_g << std::endl; + std::cout << "key_b: " << (int)p->key_b << std::endl; + std::cout << "alpha: " << (int)p->alpha << std::endl; + std::cout << "alpha_done: " << (int)p->alpha_done << std::endl; + std::cout << "numcolors: " << (int)p->numcolors << std::endl; + std::cout << "maxnumcolors: " << (int)p->maxnumcolors << std::endl; + std::cout << "numcolors_done: " << (int)p->numcolors_done << std::endl; + std::cout << "greybits: " << (int)p->greybits << std::endl; + std::cout << "greybits_done: " << (int)p->greybits_done << std::endl; +}*/ + +/*Returns how many bits needed to represent given value (max 8 bit)*/ +unsigned getValueRequiredBits(unsigned short value) +{ + if(value == 0 || value == 255) return 1; + /*The scaling of 2-bit and 4-bit values uses multiples of 85 and 17*/ + if(value % 17 == 0) return value % 85 == 0 ? 2 : 4; + return 8; +} + +/*profile must already have been inited with mode. +It's ok to set some parameters of profile to done already.*/ +static unsigned get_color_profile(ColorProfile* profile, + const unsigned char* in, size_t numpixels, + LodePNGColorMode* mode) +{ + unsigned error = 0; + size_t i; + + if(mode->bitdepth == 16) + { + for(i = 0; i < numpixels; i++) + { + unsigned short r, g, b, a; + error = getPixelColorRGBA16(&r, &g, &b, &a, in, i, mode); + if(error) break; + + /*a color is considered good for 8-bit if the first byte and the second byte are equal, + (so if it's divisible through 257), NOT necessarily if the second byte is 0*/ + if(!profile->sixteenbit_done + && (((r & 255) != ((r >> 8) & 255)) + || ((g & 255) != ((g >> 8) & 255)) + || ((b & 255) != ((b >> 8) & 255)))) + { + profile->sixteenbit = 1; + profile->sixteenbit_done = 1; + profile->greybits_done = 1; /*greybits is not applicable anymore at 16-bit*/ + profile->numcolors_done = 1; /*counting colors no longer useful, palette doesn't support 16-bit*/ + } + + if(!profile->colored_done && (r != g || r != b)) + { + profile->colored = 1; + profile->colored_done = 1; + profile->greybits_done = 1; /*greybits is not applicable anymore*/ + } + + if(!profile->alpha_done && a != 65535) + { + if(a == 0 && !(profile->key && (r != profile->key_r || g != profile->key_g || b != profile->key_b))) + { + if(!profile->key) + { + profile->key = 1; + profile->key_r = r; + profile->key_g = g; + profile->key_b = b; + } + } + else + { + profile->alpha = 1; + profile->alpha_done = 1; + profile->greybits_done = 1; /*greybits is not applicable anymore*/ + } + } + + /* Color key cannot be used if an opaque pixel also has that RGB color. */ + if(!profile->alpha_done && a == 65535 && profile->key + && r == profile->key_r && g == profile->key_g && b == profile->key_b) + { + profile->alpha = 1; + profile->alpha_done = 1; + profile->greybits_done = 1; /*greybits is not applicable anymore*/ + } + + if(!profile->greybits_done) + { + /*assuming 8-bit r, this test does not care about 16-bit*/ + unsigned bits = getValueRequiredBits(r); + if(bits > profile->greybits) profile->greybits = bits; + if(profile->greybits >= 8) profile->greybits_done = 1; + } + + if(!profile->numcolors_done) + { + /*assuming 8-bit rgba, this test does not care about 16-bit*/ + if(!color_tree_has(&profile->tree, (unsigned char)r, (unsigned char)g, (unsigned char)b, (unsigned char)a)) + { + color_tree_add(&profile->tree, (unsigned char)r, (unsigned char)g, (unsigned char)b, (unsigned char)a, + profile->numcolors); + if(profile->numcolors < 256) + { + unsigned char* p = profile->palette; + unsigned i = profile->numcolors; + p[i * 4 + 0] = (unsigned char)r; + p[i * 4 + 1] = (unsigned char)g; + p[i * 4 + 2] = (unsigned char)b; + p[i * 4 + 3] = (unsigned char)a; + } + profile->numcolors++; + if(profile->numcolors >= profile->maxnumcolors) profile->numcolors_done = 1; + } + } + + if(profile->alpha_done && profile->numcolors_done + && profile->colored_done && profile->sixteenbit_done && profile->greybits_done) + { + break; + } + }; + } + else /* < 16-bit */ + { + for(i = 0; i < numpixels; i++) + { + unsigned char r = 0, g = 0, b = 0, a = 0; + error = getPixelColorRGBA8(&r, &g, &b, &a, in, i, mode); + if(error) break; + + if(!profile->colored_done && (r != g || r != b)) + { + profile->colored = 1; + profile->colored_done = 1; + profile->greybits_done = 1; /*greybits is not applicable anymore*/ + } + + if(!profile->alpha_done && a != 255) + { + if(a == 0 && !(profile->key && (r != profile->key_r || g != profile->key_g || b != profile->key_b))) + { + if(!profile->key) + { + profile->key = 1; + profile->key_r = r; + profile->key_g = g; + profile->key_b = b; + } + } + else + { + profile->alpha = 1; + profile->alpha_done = 1; + profile->greybits_done = 1; /*greybits is not applicable anymore*/ + } + } + + /* Color key cannot be used if an opaque pixel also has that RGB color. */ + if(!profile->alpha_done && a == 255 && profile->key + && r == profile->key_r && g == profile->key_g && b == profile->key_b) + { + profile->alpha = 1; + profile->alpha_done = 1; + profile->greybits_done = 1; /*greybits is not applicable anymore*/ + } + + if(!profile->greybits_done) + { + unsigned bits = getValueRequiredBits(r); + if(bits > profile->greybits) profile->greybits = bits; + if(profile->greybits >= 8) profile->greybits_done = 1; + } + + if(!profile->numcolors_done) + { + if(!color_tree_has(&profile->tree, r, g, b, a)) + { + + color_tree_add(&profile->tree, r, g, b, a, profile->numcolors); + if(profile->numcolors < 256) + { + unsigned char* p = profile->palette; + unsigned i = profile->numcolors; + p[i * 4 + 0] = r; + p[i * 4 + 1] = g; + p[i * 4 + 2] = b; + p[i * 4 + 3] = a; + } + profile->numcolors++; + if(profile->numcolors >= profile->maxnumcolors) profile->numcolors_done = 1; + } + } + + if(profile->alpha_done && profile->numcolors_done && profile->colored_done && profile->greybits_done) + { + break; + } + }; + } + + /*make the profile's key always 16-bit for consistency*/ + if(mode->bitdepth < 16) + { + /*repeat each byte twice*/ + profile->key_r *= 257; + profile->key_g *= 257; + profile->key_b *= 257; + } + + return error; +} + +/*updates values of mode with a potentially smaller color model. mode_out should +contain the user chosen color model, but will be overwritten with the new chosen one.*/ +static unsigned doAutoChooseColor(LodePNGColorMode* mode_out, + const unsigned char* image, unsigned w, unsigned h, LodePNGColorMode* mode_in, + LodePNGAutoConvert auto_convert) +{ + ColorProfile profile; + unsigned error = 0; + int no_nibbles = auto_convert == LAC_AUTO_NO_NIBBLES || auto_convert == LAC_AUTO_NO_NIBBLES_NO_PALETTE; + int no_palette = auto_convert == LAC_AUTO_NO_PALETTE || auto_convert == LAC_AUTO_NO_NIBBLES_NO_PALETTE; + + if(auto_convert == LAC_ALPHA) + { + if(mode_out->colortype != LCT_RGBA && mode_out->colortype != LCT_GREY_ALPHA) return 0; + } + + color_profile_init(&profile, mode_in); + if(auto_convert == LAC_ALPHA) + { + profile.colored_done = 1; + profile.greybits_done = 1; + profile.numcolors_done = 1; + profile.sixteenbit_done = 1; + } + error = get_color_profile(&profile, image, w * h, mode_in); + + if(!error && auto_convert == LAC_ALPHA) + { + if(!profile.alpha) + { + mode_out->colortype = (mode_out->colortype == LCT_RGBA ? LCT_RGB : LCT_GREY); + } + } + else if(!error && auto_convert != LAC_ALPHA) + { + mode_out->key_defined = 0; + + if(profile.sixteenbit) + { + mode_out->bitdepth = 16; + if(profile.alpha) + { + mode_out->colortype = profile.colored ? LCT_RGBA : LCT_GREY_ALPHA; + } + else + { + mode_out->colortype = profile.colored ? LCT_RGB : LCT_GREY; + if(profile.key) + { + mode_out->key_defined = 1; + mode_out->key_r = profile.key_r; + mode_out->key_g = profile.key_g; + mode_out->key_b = profile.key_b; + } + } + } + else /*less than 16 bits per channel*/ + { + /*don't add palette overhead if image hasn't got a lot of pixels*/ + unsigned n = profile.numcolors; + int palette_ok = !no_palette && n <= 256 && (n * 2 < w * h); + unsigned palettebits = n <= 2 ? 1 : (n <= 4 ? 2 : (n <= 16 ? 4 : 8)); + int grey_ok = !profile.colored && !profile.alpha; /*grey without alpha, with potentially low bits*/ + if(palette_ok || grey_ok) + { + if(!palette_ok || (grey_ok && profile.greybits <= palettebits)) + { + mode_out->colortype = LCT_GREY; + mode_out->bitdepth = profile.greybits; + if(profile.key) + { + unsigned keyval = profile.key_r; + keyval &= (profile.greybits - 1); /*same subgroup of bits repeated, so taking right bits is fine*/ + mode_out->key_defined = 1; + mode_out->key_r = keyval; + mode_out->key_g = keyval; + mode_out->key_b = keyval; + } + } + else + { + /*fill in the palette*/ + unsigned i; + unsigned char* p = profile.palette; + for(i = 0; i < profile.numcolors; i++) + { + error = lodepng_palette_add(mode_out, p[i * 4 + 0], p[i * 4 + 1], p[i * 4 + 2], p[i * 4 + 3]); + if(error) break; + } + + mode_out->colortype = LCT_PALETTE; + mode_out->bitdepth = palettebits; + } + } + else /*8-bit per channel*/ + { + mode_out->bitdepth = 8; + if(profile.alpha) + { + mode_out->colortype = profile.colored ? LCT_RGBA : LCT_GREY_ALPHA; + } + else + { + mode_out->colortype = profile.colored ? LCT_RGB : LCT_GREY /*LCT_GREY normally won't occur, already done earlier*/; + if(profile.key) + { + mode_out->key_defined = 1; + mode_out->key_r = profile.key_r % 256; + mode_out->key_g = profile.key_g % 256; + mode_out->key_b = profile.key_b % 256; + } + } + } + } + } + + color_profile_cleanup(&profile); + + if(mode_out->colortype == LCT_PALETTE && mode_in->palettesize == mode_out->palettesize) + { + /*In this case keep the palette order of the input, so that the user can choose an optimal one*/ + size_t i; + for(i = 0; i < mode_in->palettesize * 4; i++) + { + mode_out->palette[i] = mode_in->palette[i]; + } + } + + if(no_nibbles && mode_out->bitdepth < 8) + { + /*palette can keep its small amount of colors, as long as no indices use it*/ + mode_out->bitdepth = 8; + } + + return error; +} + +#endif /* #ifdef LODEPNG_COMPILE_ENCODER */ + /* Paeth predicter, used by PNG filter type 4 The parameters are of type short, but should come from unsigned chars, the shorts @@ -3339,14 +3853,9 @@ static unsigned char paethPredictor(short a, short b, short c) short pb = abs(a - c); short pc = abs(a + b - c - c); - /*short pc = a + b - c; - short pa = abs(pc - a); - short pb = abs(pc - b); - pc = abs(pc - c);*/ - - if(pa <= pb && pa <= pc) return (unsigned char)a; - else if(pb <= pc) return (unsigned char)b; - else return (unsigned char)c; + if(pc < pa && pc < pb) return (unsigned char)c; + else if(pb < pa) return (unsigned char)b; + else return (unsigned char)a; } /*shared values used by multiple Adam7 related functions*/ @@ -3356,6 +3865,21 @@ static const unsigned ADAM7_IY[7] = { 0, 0, 4, 0, 2, 0, 1 }; /*y start values*/ static const unsigned ADAM7_DX[7] = { 8, 8, 4, 4, 2, 2, 1 }; /*x delta values*/ static const unsigned ADAM7_DY[7] = { 8, 8, 8, 4, 4, 2, 2 }; /*y delta values*/ +/* +Outputs various dimensions and positions in the image related to the Adam7 reduced images. +passw: output containing the width of the 7 passes +passh: output containing the height of the 7 passes +filter_passstart: output containing the index of the start and end of each + reduced image with filter bytes +padded_passstart output containing the index of the start and end of each + reduced image when without filter bytes but with padded scanlines +passstart: output containing the index of the start and end of each reduced + image without padding between scanlines, but still padding between the images +w, h: width and height of non-interlaced image +bpp: bits per pixel +"padded" is only relevant if bpp is less than 8 and a scanline or image does not + end at a full byte +*/ static void Adam7_getpassvalues(unsigned passw[7], unsigned passh[7], size_t filter_passstart[8], size_t padded_passstart[8], size_t passstart[8], unsigned w, unsigned h, unsigned bpp) { @@ -3390,65 +3914,62 @@ static void Adam7_getpassvalues(unsigned passw[7], unsigned passh[7], size_t fil /* / PNG Decoder / */ /* ////////////////////////////////////////////////////////////////////////// */ -/*read the information from the header and store it in the LodePNG_Info. return value is error*/ -void LodePNG_Decoder_inspect(LodePNG_Decoder* decoder, const unsigned char* in, size_t inlength) +/*read the information from the header and store it in the LodePNGInfo. return value is error*/ +unsigned lodepng_inspect(unsigned* w, unsigned* h, LodePNGState* state, + const unsigned char* in, size_t insize) { - if(inlength == 0 || in == 0) + LodePNGInfo* info = &state->info_png; + if(insize == 0 || in == 0) { - decoder->error = 48; /*the given data is empty*/ - return; + CERROR_RETURN_ERROR(state->error, 48); /*error: the given data is empty*/ } - if(inlength < 29) + if(insize < 29) { - decoder->error = 27; /*error: the data length is smaller than the length of a PNG header*/ - return; + CERROR_RETURN_ERROR(state->error, 27); /*error: the data length is smaller than the length of a PNG header*/ } /*when decoding a new PNG image, make sure all parameters created after previous decoding are reset*/ - LodePNG_InfoPng_cleanup(&decoder->infoPng); - LodePNG_InfoPng_init(&decoder->infoPng); - decoder->error = 0; + lodepng_info_cleanup(info); + lodepng_info_init(info); if(in[0] != 137 || in[1] != 80 || in[2] != 78 || in[3] != 71 || in[4] != 13 || in[5] != 10 || in[6] != 26 || in[7] != 10) { - decoder->error = 28; /*error: the first 8 bytes are not the correct PNG signature*/ - return; + CERROR_RETURN_ERROR(state->error, 28); /*error: the first 8 bytes are not the correct PNG signature*/ } if(in[12] != 'I' || in[13] != 'H' || in[14] != 'D' || in[15] != 'R') { - decoder->error = 29; /*error: it doesn't start with a IHDR chunk!*/ - return; + CERROR_RETURN_ERROR(state->error, 29); /*error: it doesn't start with a IHDR chunk!*/ } /*read the values given in the header*/ - decoder->infoPng.width = LodePNG_read32bitInt(&in[16]); - decoder->infoPng.height = LodePNG_read32bitInt(&in[20]); - decoder->infoPng.color.bitDepth = in[24]; - decoder->infoPng.color.colorType = in[25]; - decoder->infoPng.compressionMethod = in[26]; - decoder->infoPng.filterMethod = in[27]; - decoder->infoPng.interlaceMethod = in[28]; + *w = lodepng_read32bitInt(&in[16]); + *h = lodepng_read32bitInt(&in[20]); + info->color.bitdepth = in[24]; + info->color.colortype = (LodePNGColorType)in[25]; + info->compression_method = in[26]; + info->filter_method = in[27]; + info->interlace_method = in[28]; - if(!decoder->settings.ignoreCrc) + if(!state->decoder.ignore_crc) { - unsigned CRC = LodePNG_read32bitInt(&in[29]); - unsigned checksum = Crc32_crc(&in[12], 17); + unsigned CRC = lodepng_read32bitInt(&in[29]); + unsigned checksum = lodepng_crc32(&in[12], 17); if(CRC != checksum) { - decoder->error = 57; /*invalid CRC*/ - return; + CERROR_RETURN_ERROR(state->error, 57); /*invalid CRC*/ } } /*error: only compression method 0 is allowed in the specification*/ - if(decoder->infoPng.compressionMethod != 0) { decoder->error = 32; return; } + if(info->compression_method != 0) CERROR_RETURN_ERROR(state->error, 32); /*error: only filter method 0 is allowed in the specification*/ - if(decoder->infoPng.filterMethod != 0) { decoder->error = 33; return; } + if(info->filter_method != 0) CERROR_RETURN_ERROR(state->error, 33); /*error: only interlace methods 0 and 1 exist in the specification*/ - if(decoder->infoPng.interlaceMethod > 1) { decoder->error = 34; return; } + if(info->interlace_method > 1) CERROR_RETURN_ERROR(state->error, 34); - decoder->error = checkColorValidity(decoder->infoPng.color.colorType, decoder->infoPng.color.bitDepth); + state->error = checkColorValidity(info->color.colortype, info->color.bitdepth); + return state->error; } static unsigned unfilterScanline(unsigned char* recon, const unsigned char* scanline, const unsigned char* precon, @@ -3470,8 +3991,8 @@ static unsigned unfilterScanline(unsigned char* recon, const unsigned char* scan for(i = 0; i < length; i++) recon[i] = scanline[i]; break; case 1: - for(i = 0; i < bytewidth; i++) recon[i] = scanline[i]; - for(i = bytewidth; i < length; i++) recon[i] = scanline[i] + recon[i - bytewidth]; + for(i = 0; i < bytewidth; i++) recon[i] = scanline[i]; + for(i = bytewidth; i < length; i++) recon[i] = scanline[i] + recon[i - bytewidth]; break; case 2: if(precon) @@ -3486,13 +4007,13 @@ static unsigned unfilterScanline(unsigned char* recon, const unsigned char* scan case 3: if(precon) { - for(i = 0; i < bytewidth; i++) recon[i] = scanline[i] + precon[i] / 2; - for(i = bytewidth; i < length; i++) recon[i] = scanline[i] + ((recon[i - bytewidth] + precon[i]) / 2); + for(i = 0; i < bytewidth; i++) recon[i] = scanline[i] + precon[i] / 2; + for(i = bytewidth; i < length; i++) recon[i] = scanline[i] + ((recon[i - bytewidth] + precon[i]) / 2); } else { - for(i = 0; i < bytewidth; i++) recon[i] = scanline[i]; - for(i = bytewidth; i < length; i++) recon[i] = scanline[i] + recon[i - bytewidth] / 2; + for(i = 0; i < bytewidth; i++) recon[i] = scanline[i]; + for(i = bytewidth; i < length; i++) recon[i] = scanline[i] + recon[i - bytewidth] / 2; } break; case 4: @@ -3548,8 +4069,7 @@ static unsigned unfilter(unsigned char* out, const unsigned char* in, unsigned w size_t inindex = (1 + linebytes) * y; /*the extra filterbyte added to each row*/ unsigned char filterType = in[inindex]; - unsigned error = unfilterScanline(&out[outindex], &in[inindex + 1], prevline, bytewidth, filterType, linebytes); - if(error) return error; + CERROR_TRY_RETURN(unfilterScanline(&out[outindex], &in[inindex + 1], prevline, bytewidth, filterType, linebytes)); prevline = &out[outindex]; } @@ -3557,12 +4077,19 @@ static unsigned unfilter(unsigned char* out, const unsigned char* in, unsigned w return 0; } +/* +in: Adam7 interlaced image, with no padding bits between scanlines, but between + reduced images so that each reduced image starts at a byte. +out: the same pixels, but re-ordered so that they're now a non-interlaced image with size w*h +bpp: bits per pixel +out has the following size in bits: w * h * bpp. +in is possibly bigger due to padding bits between reduced images. +out must be big enough AND must be 0 everywhere if bpp < 8 in the current implementation +(because that's likely a little bit faster) +NOTE: comments about padding bits are only relevant if bpp < 8 +*/ static void Adam7_deinterlace(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, unsigned bpp) { - /*Note: this function works on image buffers WITHOUT padding bits at end of scanlines - with non-multiple-of-8 bit amounts, only between reduced images is padding - out must be big enough AND must be 0 everywhere if bpp < 8 in the current implementation - (because that's likely a little bit faster)*/ unsigned passw[7], passh[7]; size_t filter_passstart[8], padded_passstart[8], passstart[8]; unsigned i; @@ -3641,7 +4168,8 @@ static void removePaddingBits(unsigned char* out, const unsigned char* in, /*out must be buffer big enough to contain full image, and in must contain the full decompressed data from the IDAT chunks (with filter index bytes and possible padding bits) return value is error*/ -static unsigned postProcessScanlines(unsigned char* out, unsigned char* in, const LodePNG_InfoPng* infoPng) +static unsigned postProcessScanlines(unsigned char* out, unsigned char* in, + unsigned w, unsigned h, const LodePNGInfo* info_png) { /* This function converts the filtered-padded-interlaced data into pure 2D image buffer with the PNG's colortype. @@ -3650,23 +4178,20 @@ static unsigned postProcessScanlines(unsigned char* out, unsigned char* in, cons *) if adam7: 1) 7x unfilter 2) 7x remove padding bits 3) Adam7_deinterlace NOTE: the in buffer will be overwritten with intermediate data! */ - unsigned bpp = LodePNG_InfoColor_getBpp(&infoPng->color); - unsigned w = infoPng->width; - unsigned h = infoPng->height; - unsigned error = 0; + unsigned bpp = lodepng_get_bpp(&info_png->color); if(bpp == 0) return 31; /*error: invalid colortype*/ - if(infoPng->interlaceMethod == 0) + if(info_png->interlace_method == 0) { if(bpp < 8 && w * bpp != ((w * bpp + 7) / 8) * 8) { - error = unfilter(in, in, w, h, bpp); - if(error) return error; + CERROR_TRY_RETURN(unfilter(in, in, w, h, bpp)); removePaddingBits(out, in, w * bpp, ((w * bpp + 7) / 8) * 8, h); } - else error = unfilter(out, in, w, h, bpp); /*we can immediatly filter into the out buffer, no other steps needed*/ + /*we can immediatly filter into the out buffer, no other steps needed*/ + else CERROR_TRY_RETURN(unfilter(out, in, w, h, bpp)); } - else /*interlaceMethod is 1 (Adam7)*/ + else /*interlace_method is 1 (Adam7)*/ { unsigned passw[7], passh[7]; size_t filter_passstart[8], padded_passstart[8], passstart[8]; unsigned i; @@ -3675,8 +4200,7 @@ static unsigned postProcessScanlines(unsigned char* out, unsigned char* in, cons for(i = 0; i < 7; i++) { - error = unfilter(&in[padded_passstart[i]], &in[filter_passstart[i]], passw[i], passh[i], bpp); - if(error) return error; + CERROR_TRY_RETURN(unfilter(&in[padded_passstart[i]], &in[filter_passstart[i]], passw[i], passh[i], bpp)); /*TODO: possible efficiency improvement: if in this reduced image the bits fit nicely in 1 scanline, move bytes instead of bits or move not at all*/ if(bpp < 8) @@ -3691,11 +4215,319 @@ static unsigned postProcessScanlines(unsigned char* out, unsigned char* in, cons Adam7_deinterlace(out, in, w, h, bpp); } + return 0; +} + +static unsigned readChunk_PLTE(LodePNGColorMode* color, const unsigned char* data, size_t chunkLength) +{ + unsigned pos = 0, i; + if(color->palette) myfree(color->palette); + color->palettesize = chunkLength / 3; + color->palette = (unsigned char*)mymalloc(4 * color->palettesize); + if(!color->palette && color->palettesize) + { + color->palettesize = 0; + return 83; /*alloc fail*/ + } + if(color->palettesize > 256) return 38; /*error: palette too big*/ + + for(i = 0; i < color->palettesize; i++) + { + color->palette[4 * i + 0] = data[pos++]; /*R*/ + color->palette[4 * i + 1] = data[pos++]; /*G*/ + color->palette[4 * i + 2] = data[pos++]; /*B*/ + color->palette[4 * i + 3] = 255; /*alpha*/ + } + + return 0; /* OK */ +} + +static unsigned readChunk_tRNS(LodePNGColorMode* color, const unsigned char* data, size_t chunkLength) +{ + unsigned i; + if(color->colortype == LCT_PALETTE) + { + /*error: more alpha values given than there are palette entries*/ + if(chunkLength > color->palettesize) return 38; + + for(i = 0; i < chunkLength; i++) color->palette[4 * i + 3] = data[i]; + } + else if(color->colortype == LCT_GREY) + { + /*error: this chunk must be 2 bytes for greyscale image*/ + if(chunkLength != 2) return 30; + + color->key_defined = 1; + color->key_r = color->key_g = color->key_b = 256 * data[0] + data[1]; + } + else if(color->colortype == LCT_RGB) + { + /*error: this chunk must be 6 bytes for RGB image*/ + if(chunkLength != 6) return 41; + + color->key_defined = 1; + color->key_r = 256 * data[0] + data[1]; + color->key_g = 256 * data[2] + data[3]; + color->key_b = 256 * data[4] + data[5]; + } + else return 42; /*error: tRNS chunk not allowed for other color models*/ + + return 0; /* OK */ +} + + +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS +/*background color chunk (bKGD)*/ +static unsigned readChunk_bKGD(LodePNGInfo* info, const unsigned char* data, size_t chunkLength) +{ + if(info->color.colortype == LCT_PALETTE) + { + /*error: this chunk must be 1 byte for indexed color image*/ + if(chunkLength != 1) return 43; + + info->background_defined = 1; + info->background_r = info->background_g = info->background_b = data[0]; + } + else if(info->color.colortype == LCT_GREY || info->color.colortype == LCT_GREY_ALPHA) + { + /*error: this chunk must be 2 bytes for greyscale image*/ + if(chunkLength != 2) return 44; + + info->background_defined = 1; + info->background_r = info->background_g = info->background_b + = 256 * data[0] + data[1]; + } + else if(info->color.colortype == LCT_RGB || info->color.colortype == LCT_RGBA) + { + /*error: this chunk must be 6 bytes for greyscale image*/ + if(chunkLength != 6) return 45; + + info->background_defined = 1; + info->background_r = 256 * data[0] + data[1]; + info->background_g = 256 * data[2] + data[3]; + info->background_b = 256 * data[4] + data[5]; + } + + return 0; /* OK */ +} + +/*text chunk (tEXt)*/ +static unsigned readChunk_tEXt(LodePNGInfo* info, const unsigned char* data, size_t chunkLength) +{ + unsigned error = 0; + char *key = 0, *str = 0; + unsigned i; + + while(!error) /*not really a while loop, only used to break on error*/ + { + unsigned length, string2_begin; + + length = 0; + while(length < chunkLength && data[length] != 0) length++; + /*even though it's not allowed by the standard, no error is thrown if + there's no null termination char, if the text is empty*/ + if(length < 1 || length > 79) CERROR_BREAK(error, 89); /*keyword too short or long*/ + + key = (char*)mymalloc(length + 1); + if(!key) CERROR_BREAK(error, 83); /*alloc fail*/ + + key[length] = 0; + for(i = 0; i < length; i++) key[i] = data[i]; + + string2_begin = length + 1; /*skip keyword null terminator*/ + + length = chunkLength < string2_begin ? 0 : chunkLength - string2_begin; + str = (char*)mymalloc(length + 1); + if(!str) CERROR_BREAK(error, 83); /*alloc fail*/ + + str[length] = 0; + for(i = 0; i < length; i++) str[i] = data[string2_begin + i]; + + error = lodepng_add_text(info, key, str); + + break; + } + + myfree(key); + myfree(str); + return error; } +/*compressed text chunk (zTXt)*/ +static unsigned readChunk_zTXt(LodePNGInfo* info, const LodePNGDecompressSettings* zlibsettings, + const unsigned char* data, size_t chunkLength) +{ + unsigned error = 0; + unsigned i; + + unsigned length, string2_begin; + char *key = 0; + ucvector decoded; + + ucvector_init(&decoded); + + while(!error) /*not really a while loop, only used to break on error*/ + { + for(length = 0; length < chunkLength && data[length] != 0; length++) ; + if(length + 2 >= chunkLength) CERROR_BREAK(error, 75); /*no null termination, corrupt?*/ + if(length < 1 || length > 79) CERROR_BREAK(error, 89); /*keyword too short or long*/ + + key = (char*)mymalloc(length + 1); + if(!key) CERROR_BREAK(error, 83); /*alloc fail*/ + + key[length] = 0; + for(i = 0; i < length; i++) key[i] = data[i]; + + if(data[length + 1] != 0) CERROR_BREAK(error, 72); /*the 0 byte indicating compression must be 0*/ + + string2_begin = length + 2; + if(string2_begin > chunkLength) CERROR_BREAK(error, 75); /*no null termination, corrupt?*/ + + length = chunkLength - string2_begin; + /*will fail if zlib error, e.g. if length is too small*/ + error = zlib_decompress(&decoded.data, &decoded.size, + (unsigned char*)(&data[string2_begin]), + length, zlibsettings); + if(error) break; + ucvector_push_back(&decoded, 0); + + error = lodepng_add_text(info, key, (char*)decoded.data); + + break; + } + + myfree(key); + ucvector_cleanup(&decoded); + + return error; +} + +/*international text chunk (iTXt)*/ +static unsigned readChunk_iTXt(LodePNGInfo* info, const LodePNGDecompressSettings* zlibsettings, + const unsigned char* data, size_t chunkLength) +{ + unsigned error = 0; + unsigned i; + + unsigned length, begin, compressed; + char *key = 0, *langtag = 0, *transkey = 0; + ucvector decoded; + ucvector_init(&decoded); + + while(!error) /*not really a while loop, only used to break on error*/ + { + /*Quick check if the chunk length isn't too small. Even without check + it'd still fail with other error checks below if it's too short. This just gives a different error code.*/ + if(chunkLength < 5) CERROR_BREAK(error, 30); /*iTXt chunk too short*/ + + /*read the key*/ + for(length = 0; length < chunkLength && data[length] != 0; length++) ; + if(length + 3 >= chunkLength) CERROR_BREAK(error, 75); /*no null termination char, corrupt?*/ + if(length < 1 || length > 79) CERROR_BREAK(error, 89); /*keyword too short or long*/ + + key = (char*)mymalloc(length + 1); + if(!key) CERROR_BREAK(error, 83); /*alloc fail*/ + + key[length] = 0; + for(i = 0; i < length; i++) key[i] = data[i]; + + /*read the compression method*/ + compressed = data[length + 1]; + if(data[length + 2] != 0) CERROR_BREAK(error, 72); /*the 0 byte indicating compression must be 0*/ + + /*even though it's not allowed by the standard, no error is thrown if + there's no null termination char, if the text is empty for the next 3 texts*/ + + /*read the langtag*/ + begin = length + 3; + length = 0; + for(i = begin; i < chunkLength && data[i] != 0; i++) length++; + + langtag = (char*)mymalloc(length + 1); + if(!langtag) CERROR_BREAK(error, 83); /*alloc fail*/ + + langtag[length] = 0; + for(i = 0; i < length; i++) langtag[i] = data[begin + i]; + + /*read the transkey*/ + begin += length + 1; + length = 0; + for(i = begin; i < chunkLength && data[i] != 0; i++) length++; + + transkey = (char*)mymalloc(length + 1); + if(!transkey) CERROR_BREAK(error, 83); /*alloc fail*/ + + transkey[length] = 0; + for(i = 0; i < length; i++) transkey[i] = data[begin + i]; + + /*read the actual text*/ + begin += length + 1; + + length = chunkLength < begin ? 0 : chunkLength - begin; + + if(compressed) + { + /*will fail if zlib error, e.g. if length is too small*/ + error = zlib_decompress(&decoded.data, &decoded.size, + (unsigned char*)(&data[begin]), + length, zlibsettings); + if(error) break; + if(decoded.allocsize < decoded.size) decoded.allocsize = decoded.size; + ucvector_push_back(&decoded, 0); + } + else + { + if(!ucvector_resize(&decoded, length + 1)) CERROR_BREAK(error, 83 /*alloc fail*/); + + decoded.data[length] = 0; + for(i = 0; i < length; i++) decoded.data[i] = data[begin + i]; + } + + error = lodepng_add_itext(info, key, langtag, transkey, (char*)decoded.data); + + break; + } + + myfree(key); + myfree(langtag); + myfree(transkey); + ucvector_cleanup(&decoded); + + return error; +} + +static unsigned readChunk_tIME(LodePNGInfo* info, const unsigned char* data, size_t chunkLength) +{ + if(chunkLength != 7) return 73; /*invalid tIME chunk size*/ + + info->time_defined = 1; + info->time.year = 256 * data[0] + data[+ 1]; + info->time.month = data[2]; + info->time.day = data[3]; + info->time.hour = data[4]; + info->time.minute = data[5]; + info->time.second = data[6]; + + return 0; /* OK */ +} + +static unsigned readChunk_pHYs(LodePNGInfo* info, const unsigned char* data, size_t chunkLength) +{ + if(chunkLength != 9) return 74; /*invalid pHYs chunk size*/ + + info->phys_defined = 1; + info->phys_x = 16777216 * data[0] + 65536 * data[1] + 256 * data[2] + data[3]; + info->phys_y = 16777216 * data[4] + 65536 * data[5] + 256 * data[6] + data[7]; + info->phys_unit = data[8]; + + return 0; /* OK */ +} +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + /*read a PNG, the result will be in the same color type as the PNG (hence "generic")*/ -static void decodeGeneric(LodePNG_Decoder* decoder, unsigned char** out, size_t* outsize, +static void decodeGeneric(unsigned char** out, unsigned* w, unsigned* h, + LodePNGState* state, const unsigned char* in, size_t insize) { unsigned char IEND = 0; @@ -3705,394 +4537,165 @@ static void decodeGeneric(LodePNG_Decoder* decoder, unsigned char** out, size_t* /*for unknown chunk order*/ unsigned unknown = 0; -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS unsigned critical_pos = 1; /*1 = after IHDR, 2 = after PLTE, 3 = after IDAT*/ #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ /*provide some proper output values if error will happen*/ *out = 0; - *outsize = 0; - LodePNG_Decoder_inspect(decoder, in, insize); /*reads header and resets other parameters in decoder->infoPng*/ - if(decoder->error) return; + state->error = lodepng_inspect(w, h, state, in, insize); /*reads header and resets other parameters in state->info_png*/ + if(state->error) return; ucvector_init(&idat); - chunk = &in[33]; /*first byte of the first chunk after the header*/ /*loop through the chunks, ignoring unknown chunks and stopping at IEND chunk. IDAT data is put at the start of the in buffer*/ - while(!IEND) + while(!IEND && !state->error) { unsigned chunkLength; const unsigned char* data; /*the data in the chunk*/ /*error: size of the in buffer too small to contain next chunk*/ - if((size_t)((chunk - in) + 12) > insize || chunk < in) CERROR_BREAK(decoder->error, 30); + if((size_t)((chunk - in) + 12) > insize || chunk < in) CERROR_BREAK(state->error, 30); /*length of the data of the chunk, excluding the length bytes, chunk type and CRC bytes*/ - chunkLength = LodePNG_chunk_length(chunk); + chunkLength = lodepng_chunk_length(chunk); /*error: chunk length larger than the max PNG chunk size*/ - if(chunkLength > 2147483647) CERROR_BREAK(decoder->error, 63); + if(chunkLength > 2147483647) CERROR_BREAK(state->error, 63); if((size_t)((chunk - in) + chunkLength + 12) > insize || (chunk + chunkLength + 12) < in) { - CERROR_BREAK(decoder->error, 64); /*error: size of the in buffer too small to contain next chunk*/ + CERROR_BREAK(state->error, 64); /*error: size of the in buffer too small to contain next chunk*/ } - data = LodePNG_chunk_data_const(chunk); + data = lodepng_chunk_data_const(chunk); /*IDAT chunk, containing compressed image data*/ - if(LodePNG_chunk_type_equals(chunk, "IDAT")) + if(lodepng_chunk_type_equals(chunk, "IDAT")) { size_t oldsize = idat.size; - if(!ucvector_resize(&idat, oldsize + chunkLength)) CERROR_BREAK(decoder->error, 9936 /*alloc fail*/); + if(!ucvector_resize(&idat, oldsize + chunkLength)) CERROR_BREAK(state->error, 83 /*alloc fail*/); for(i = 0; i < chunkLength; i++) idat.data[oldsize + i] = data[i]; -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS critical_pos = 3; -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ } /*IEND chunk*/ - else if(LodePNG_chunk_type_equals(chunk, "IEND")) + else if(lodepng_chunk_type_equals(chunk, "IEND")) { IEND = 1; } /*palette chunk (PLTE)*/ - else if(LodePNG_chunk_type_equals(chunk, "PLTE")) + else if(lodepng_chunk_type_equals(chunk, "PLTE")) { - unsigned pos = 0; - if(decoder->infoPng.color.palette) free(decoder->infoPng.color.palette); - decoder->infoPng.color.palettesize = chunkLength / 3; - decoder->infoPng.color.palette = (unsigned char*)malloc(4 * decoder->infoPng.color.palettesize); - if(!decoder->infoPng.color.palette && decoder->infoPng.color.palettesize) - { - decoder->infoPng.color.palettesize = 0; - CERROR_BREAK(decoder->error, 9937); /*alloc fail*/ - } - if(decoder->infoPng.color.palettesize > 256) CERROR_BREAK(decoder->error, 38); /*error: palette too big*/ - - for(i = 0; i < decoder->infoPng.color.palettesize; i++) - { - decoder->infoPng.color.palette[4 * i + 0] = data[pos++]; /*R*/ - decoder->infoPng.color.palette[4 * i + 1] = data[pos++]; /*G*/ - decoder->infoPng.color.palette[4 * i + 2] = data[pos++]; /*B*/ - decoder->infoPng.color.palette[4 * i + 3] = 255; /*alpha*/ - } -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS + state->error = readChunk_PLTE(&state->info_png.color, data, chunkLength); + if(state->error) break; +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS critical_pos = 2; -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ } /*palette transparency chunk (tRNS)*/ - else if(LodePNG_chunk_type_equals(chunk, "tRNS")) + else if(lodepng_chunk_type_equals(chunk, "tRNS")) { - if(decoder->infoPng.color.colorType == 3) - { - /*error: more alpha values given than there are palette entries*/ - if(chunkLength > decoder->infoPng.color.palettesize) CERROR_BREAK(decoder->error, 38); - - for(i = 0; i < chunkLength; i++) decoder->infoPng.color.palette[4 * i + 3] = data[i]; - } - else if(decoder->infoPng.color.colorType == 0) - { - /*error: this chunk must be 2 bytes for greyscale image*/ - if(chunkLength != 2) CERROR_BREAK(decoder->error, 30); - - decoder->infoPng.color.key_defined = 1; - decoder->infoPng.color.key_r = decoder->infoPng.color.key_g - = decoder->infoPng.color.key_b = 256 * data[0] + data[1]; - } - else if(decoder->infoPng.color.colorType == 2) - { - /*error: this chunk must be 6 bytes for RGB image*/ - if(chunkLength != 6) CERROR_BREAK(decoder->error, 41); - - decoder->infoPng.color.key_defined = 1; - decoder->infoPng.color.key_r = 256 * data[0] + data[1]; - decoder->infoPng.color.key_g = 256 * data[2] + data[3]; - decoder->infoPng.color.key_b = 256 * data[4] + data[5]; - } - else CERROR_BREAK(decoder->error, 42); /*error: tRNS chunk not allowed for other color models*/ + state->error = readChunk_tRNS(&state->info_png.color, data, chunkLength); + if(state->error) break; } #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS /*background color chunk (bKGD)*/ - else if(LodePNG_chunk_type_equals(chunk, "bKGD")) + else if(lodepng_chunk_type_equals(chunk, "bKGD")) { - if(decoder->infoPng.color.colorType == 3) - { - /*error: this chunk must be 1 byte for indexed color image*/ - if(chunkLength != 1) CERROR_BREAK(decoder->error, 43); - - decoder->infoPng.background_defined = 1; - decoder->infoPng.background_r = decoder->infoPng.background_g = decoder->infoPng.background_b = data[0]; - } - else if(decoder->infoPng.color.colorType == 0 || decoder->infoPng.color.colorType == 4) - { - /*error: this chunk must be 2 bytes for greyscale image*/ - if(chunkLength != 2) CERROR_BREAK(decoder->error, 44); - - decoder->infoPng.background_defined = 1; - decoder->infoPng.background_r = decoder->infoPng.background_g = decoder->infoPng.background_b - = 256 * data[0] + data[1]; - } - else if(decoder->infoPng.color.colorType == 2 || decoder->infoPng.color.colorType == 6) - { - /*error: this chunk must be 6 bytes for greyscale image*/ - if(chunkLength != 6) CERROR_BREAK(decoder->error, 45); - - decoder->infoPng.background_defined = 1; - decoder->infoPng.background_r = 256 * data[0] + data[1]; - decoder->infoPng.background_g = 256 * data[2] + data[3]; - decoder->infoPng.background_b = 256 * data[4] + data[5]; - } + state->error = readChunk_bKGD(&state->info_png, data, chunkLength); + if(state->error) break; } /*text chunk (tEXt)*/ - else if(LodePNG_chunk_type_equals(chunk, "tEXt")) + else if(lodepng_chunk_type_equals(chunk, "tEXt")) { - if(decoder->settings.readTextChunks) + if(state->decoder.read_text_chunks) { - char *key = 0, *str = 0; - - while(!decoder->error) /*not really a while loop, only used to break on error*/ - { - unsigned length, string2_begin; - - length = 0; - while(length < chunkLength && data[length] != 0) length++; - /*error, end reached, no null terminator?*/ - if(length + 1 >= chunkLength) CERROR_BREAK(decoder->error, 75); - - key = (char*)malloc(length + 1); - if(!key) CERROR_BREAK(decoder->error, 9938); /*alloc fail*/ - - key[length] = 0; - for(i = 0; i < length; i++) key[i] = data[i]; - - string2_begin = length + 1; - /*error, end reached, no null terminator?*/ - if(string2_begin > chunkLength) CERROR_BREAK(decoder->error, 75); - - length = chunkLength - string2_begin; - str = (char*)malloc(length + 1); - if(!str) CERROR_BREAK(decoder->error, 9939); /*alloc fail*/ - - str[length] = 0; - for(i = 0; i < length; i++) str[i] = data[string2_begin + i]; - - decoder->error = LodePNG_Text_add(&decoder->infoPng.text, key, str); - - break; - } - - free(key); - free(str); + state->error = readChunk_tEXt(&state->info_png, data, chunkLength); + if(state->error) break; } } /*compressed text chunk (zTXt)*/ - else if(LodePNG_chunk_type_equals(chunk, "zTXt")) + else if(lodepng_chunk_type_equals(chunk, "zTXt")) { - if(decoder->settings.readTextChunks) + if(state->decoder.read_text_chunks) { - unsigned length, string2_begin; - char *key = 0; - ucvector decoded; - - ucvector_init(&decoded); - - while(!decoder->error) /*not really a while loop, only used to break on error*/ - { - for(length = 0; length < chunkLength && data[length] != 0; length++) ; - if(length + 2 >= chunkLength) CERROR_BREAK(decoder->error, 75); /*no null termination, corrupt?*/ - - key = (char*)malloc(length + 1); - if(!key) CERROR_BREAK(decoder->error, 9940); /*alloc fail*/ - - key[length] = 0; - for(i = 0; i < length; i++) key[i] = data[i]; - - if(data[length + 1] != 0) CERROR_BREAK(decoder->error, 72); /*the 0 byte indicating compression must be 0*/ - - string2_begin = length + 2; - if(string2_begin > chunkLength) CERROR_BREAK(decoder->error, 75); /*no null termination, corrupt?*/ - - length = chunkLength - string2_begin; - decoder->error = LodePNG_zlib_decompress(&decoded.data, &decoded.size, - (unsigned char*)(&data[string2_begin]), - length, &decoder->settings.zlibsettings); - if(decoder->error) break; - ucvector_push_back(&decoded, 0); - - decoder->error = LodePNG_Text_add(&decoder->infoPng.text, key, (char*)decoded.data); - - break; - } - - free(key); - ucvector_cleanup(&decoded); - if(decoder->error) break; + state->error = readChunk_zTXt(&state->info_png, &state->decoder.zlibsettings, data, chunkLength); + if(state->error) break; } } /*international text chunk (iTXt)*/ - else if(LodePNG_chunk_type_equals(chunk, "iTXt")) + else if(lodepng_chunk_type_equals(chunk, "iTXt")) { - if(decoder->settings.readTextChunks) + if(state->decoder.read_text_chunks) { - unsigned length, begin, compressed; - char *key = 0, *langtag = 0, *transkey = 0; - ucvector decoded; - ucvector_init(&decoded); - - while(!decoder->error) /*not really a while loop, only used to break on error*/ - { - /*Quick check if the chunk length isn't too small. Even without check - it'd still fail with other error checks below if it's too short. This just gives a different error code.*/ - if(chunkLength < 5) CERROR_BREAK(decoder->error, 30); /*iTXt chunk too short*/ - - /*read the key*/ - for(length = 0; length < chunkLength && data[length] != 0; length++) ; - if(length + 2 >= chunkLength) CERROR_BREAK(decoder->error, 75); /*no null termination char found*/ - - key = (char*)malloc(length + 1); - if(!key) CERROR_BREAK(decoder->error, 9941); /*alloc fail*/ - - key[length] = 0; - for(i = 0; i < length; i++) key[i] = data[i]; - - /*read the compression method*/ - compressed = data[length + 1]; - if(data[length + 2] != 0) CERROR_BREAK(decoder->error, 72); /*the 0 byte indicating compression must be 0*/ - - /*read the langtag*/ - begin = length + 3; - length = 0; - for(i = begin; i < chunkLength && data[i] != 0; i++) length++; - if(begin + length + 1 >= chunkLength) CERROR_BREAK(decoder->error, 75); /*no null termination char found*/ - - langtag = (char*)malloc(length + 1); - if(!langtag) CERROR_BREAK(decoder->error, 9942); /*alloc fail*/ - - langtag[length] = 0; - for(i = 0; i < length; i++) langtag[i] = data[begin + i]; - - /*read the transkey*/ - begin += length + 1; - length = 0; - for(i = begin; i < chunkLength && data[i] != 0; i++) length++; - if(begin + length + 1 >= chunkLength) CERROR_BREAK(decoder->error, 75); /*no null termination, corrupt?*/ - - transkey = (char*)malloc(length + 1); - if(!transkey) CERROR_BREAK(decoder->error, 9943); /*alloc fail*/ - - transkey[length] = 0; - for(i = 0; i < length; i++) transkey[i] = data[begin + i]; - - /*read the actual text*/ - begin += length + 1; - if(begin > chunkLength) CERROR_BREAK(decoder->error, 75); /*no null termination, corrupt?*/ - - length = chunkLength - begin; - - if(compressed) - { - decoder->error = LodePNG_zlib_decompress(&decoded.data, &decoded.size, - (unsigned char*)(&data[begin]), - length, &decoder->settings.zlibsettings); - if(decoder->error) break; - ucvector_push_back(&decoded, 0); - } - else - { - if(!ucvector_resize(&decoded, length + 1)) CERROR_BREAK(decoder->error, 9944 /*alloc fail*/); - - decoded.data[length] = 0; - for(i = 0; i < length; i++) decoded.data[i] = data[begin + i]; - } - - decoder->error = LodePNG_IText_add(&decoder->infoPng.itext, key, langtag, transkey, (char*)decoded.data); - - break; - } - - free(key); - free(langtag); - free(transkey); - ucvector_cleanup(&decoded); - if(decoder->error) break; + state->error = readChunk_iTXt(&state->info_png, &state->decoder.zlibsettings, data, chunkLength); + if(state->error) break; } } - else if(LodePNG_chunk_type_equals(chunk, "tIME")) + else if(lodepng_chunk_type_equals(chunk, "tIME")) { - if(chunkLength != 7) CERROR_BREAK(decoder->error, 73); /*invalid tIME chunk size*/ - - decoder->infoPng.time_defined = 1; - decoder->infoPng.time.year = 256 * data[0] + data[+ 1]; - decoder->infoPng.time.month = data[2]; - decoder->infoPng.time.day = data[3]; - decoder->infoPng.time.hour = data[4]; - decoder->infoPng.time.minute = data[5]; - decoder->infoPng.time.second = data[6]; + state->error = readChunk_tIME(&state->info_png, data, chunkLength); + if(state->error) break; } - else if(LodePNG_chunk_type_equals(chunk, "pHYs")) + else if(lodepng_chunk_type_equals(chunk, "pHYs")) { - if(chunkLength != 9) CERROR_BREAK(decoder->error, 74); /*invalid pHYs chunk size*/ - - decoder->infoPng.phys_defined = 1; - decoder->infoPng.phys_x = 16777216 * data[0] + 65536 * data[1] + 256 * data[2] + data[3]; - decoder->infoPng.phys_y = 16777216 * data[4] + 65536 * data[5] + 256 * data[6] + data[7]; - decoder->infoPng.phys_unit = data[8]; + state->error = readChunk_pHYs(&state->info_png, data, chunkLength); + if(state->error) break; } #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ else /*it's not an implemented chunk type, so ignore it: skip over the data*/ { /*error: unknown critical chunk (5th bit of first byte of chunk type is 0)*/ - if(LodePNG_chunk_critical(chunk)) CERROR_BREAK(decoder->error, 69); + if(!lodepng_chunk_ancillary(chunk)) CERROR_BREAK(state->error, 69); unknown = 1; -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS - if(decoder->settings.rememberUnknownChunks) +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + if(state->decoder.remember_unknown_chunks) { - LodePNG_UnknownChunks* unknown = &decoder->infoPng.unknown_chunks; - decoder->error = LodePNG_append_chunk(&unknown->data[critical_pos - 1], - &unknown->datasize[critical_pos - 1], chunk); - if(decoder->error) break; + state->error = lodepng_chunk_append(&state->info_png.unknown_chunks_data[critical_pos - 1], + &state->info_png.unknown_chunks_size[critical_pos - 1], chunk); + if(state->error) break; } -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ } - if(!decoder->settings.ignoreCrc && !unknown) /*check CRC if wanted, only on known chunk types*/ + if(!state->decoder.ignore_crc && !unknown) /*check CRC if wanted, only on known chunk types*/ { - if(LodePNG_chunk_check_crc(chunk)) CERROR_BREAK(decoder->error, 57); /*invalid CRC*/ + if(lodepng_chunk_check_crc(chunk)) CERROR_BREAK(state->error, 57); /*invalid CRC*/ } - if(!IEND) chunk = LodePNG_chunk_next_const(chunk); + if(!IEND) chunk = lodepng_chunk_next_const(chunk); } - if(!decoder->error) + if(!state->error) { ucvector scanlines; ucvector_init(&scanlines); /*maximum final image length is already reserved in the vector's length - this is not really necessary*/ - if(!ucvector_resize(&scanlines, ((decoder->infoPng.width * (decoder->infoPng.height - * LodePNG_InfoColor_getBpp(&decoder->infoPng.color) + 7)) / 8) + decoder->infoPng.height)) + if(!ucvector_resize(&scanlines, lodepng_get_raw_size(*w, *h, &state->info_png.color) + *h)) { - decoder->error = 9945; /*alloc fail*/ + state->error = 83; /*alloc fail*/ } - if(!decoder->error) + if(!state->error) { /*decompress with the Zlib decompressor*/ - decoder->error = LodePNG_zlib_decompress(&scanlines.data, &scanlines.size, idat.data, - idat.size, &decoder->settings.zlibsettings); + state->error = zlib_decompress(&scanlines.data, &scanlines.size, idat.data, + idat.size, &state->decoder.zlibsettings); } - if(!decoder->error) + if(!state->error) { ucvector outv; ucvector_init(&outv); - if(!ucvector_resizev(&outv, (decoder->infoPng.height * decoder->infoPng.width - * LodePNG_InfoColor_getBpp(&decoder->infoPng.color) + 7) / 8, 0)) decoder->error = 9946; /*alloc fail*/ - if(!decoder->error) decoder->error = postProcessScanlines(outv.data, scanlines.data, &decoder->infoPng); + if(!ucvector_resizev(&outv, + lodepng_get_raw_size(*w, *h, &state->info_png.color), 0)) state->error = 83; /*alloc fail*/ + if(!state->error) state->error = postProcessScanlines(outv.data, scanlines.data, *w, *h, &state->info_png); *out = outv.data; - *outsize = outv.size; } ucvector_cleanup(&scanlines); } @@ -4100,142 +4703,143 @@ static void decodeGeneric(LodePNG_Decoder* decoder, unsigned char** out, size_t* ucvector_cleanup(&idat); } -void LodePNG_Decoder_decode(LodePNG_Decoder* decoder, unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize) +unsigned lodepng_decode(unsigned char** out, unsigned* w, unsigned* h, + LodePNGState* state, + const unsigned char* in, size_t insize) { *out = 0; - *outsize = 0; - decodeGeneric(decoder, out, outsize, in, insize); - if(decoder->error) return; - if(!decoder->settings.color_convert || LodePNG_InfoColor_equal(&decoder->infoRaw.color, &decoder->infoPng.color)) + decodeGeneric(out, w, h, state, in, insize); + if(state->error) return state->error; + if(!state->decoder.color_convert || lodepng_color_mode_equal(&state->info_raw, &state->info_png.color)) { /*same color type, no copying or converting of data needed*/ - /*store the infoPng color settings on the infoRaw so that the infoRaw still reflects what colorType + /*store the info_png color settings on the info_raw so that the info_raw still reflects what colortype the raw image has to the end user*/ - if(!decoder->settings.color_convert) + if(!state->decoder.color_convert) { - decoder->error = LodePNG_InfoColor_copy(&decoder->infoRaw.color, &decoder->infoPng.color); - if(decoder->error) return; + state->error = lodepng_color_mode_copy(&state->info_raw, &state->info_png.color); + if(state->error) return state->error; } } else { /*color conversion needed; sort of copy of the data*/ unsigned char* data = *out; + size_t outsize; /*TODO: check if this works according to the statement in the documentation: "The converter can convert from greyscale input color type, to 8-bit greyscale or greyscale with alpha"*/ - if(!(decoder->infoRaw.color.colorType == 2 || decoder->infoRaw.color.colorType == 6) - && !(decoder->infoRaw.color.bitDepth == 8)) + if(!(state->info_raw.colortype == LCT_RGB || state->info_raw.colortype == LCT_RGBA) + && !(state->info_raw.bitdepth == 8)) { - decoder->error = 56; /*unsupported color mode conversion*/ - return; + return 56; /*unsupported color mode conversion*/ } - *outsize = (decoder->infoPng.width * decoder->infoPng.height - * LodePNG_InfoColor_getBpp(&decoder->infoRaw.color) + 7) / 8; - *out = (unsigned char*)malloc(*outsize); + outsize = lodepng_get_raw_size(*w, *h, &state->info_raw); + *out = (unsigned char*)mymalloc(outsize); if(!(*out)) { - decoder->error = 9947; /*alloc fail*/ - *outsize = 0; + state->error = 83; /*alloc fail*/ } - else decoder->error = LodePNG_convert(*out, data, &decoder->infoRaw.color, &decoder->infoPng.color, - decoder->infoPng.width, decoder->infoPng.height); - free(data); + else state->error = lodepng_convert(*out, data, &state->info_raw, &state->info_png.color, *w, *h); + myfree(data); } + return state->error; } -unsigned LodePNG_decode(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, - size_t insize, unsigned colorType, unsigned bitDepth) +unsigned lodepng_decode_memory(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, + size_t insize, LodePNGColorType colortype, unsigned bitdepth) { unsigned error; - size_t dummy_size; - LodePNG_Decoder decoder; - LodePNG_Decoder_init(&decoder); - decoder.infoRaw.color.colorType = colorType; - decoder.infoRaw.color.bitDepth = bitDepth; - LodePNG_Decoder_decode(&decoder, out, &dummy_size, in, insize); - error = decoder.error; - *w = decoder.infoPng.width; - *h = decoder.infoPng.height; - LodePNG_Decoder_cleanup(&decoder); + LodePNGState state; + lodepng_state_init(&state); + state.info_raw.colortype = colortype; + state.info_raw.bitdepth = bitdepth; + error = lodepng_decode(out, w, h, &state, in, insize); + lodepng_state_cleanup(&state); return error; } -unsigned LodePNG_decode32(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, size_t insize) +unsigned lodepng_decode32(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, size_t insize) { - return LodePNG_decode(out, w, h, in, insize, 6, 8); + return lodepng_decode_memory(out, w, h, in, insize, LCT_RGBA, 8); } -unsigned LodePNG_decode24(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, size_t insize) +unsigned lodepng_decode24(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, size_t insize) { - return LodePNG_decode(out, w, h, in, insize, 2, 8); + return lodepng_decode_memory(out, w, h, in, insize, LCT_RGB, 8); } #ifdef LODEPNG_COMPILE_DISK -unsigned LodePNG_decode_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename, - unsigned colorType, unsigned bitDepth) +unsigned lodepng_decode_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename, + LodePNGColorType colortype, unsigned bitdepth) { unsigned char* buffer; size_t buffersize; unsigned error; - error = LodePNG_loadFile(&buffer, &buffersize, filename); - if(!error) error = LodePNG_decode(out, w, h, buffer, buffersize, colorType, bitDepth); - free(buffer); + error = lodepng_load_file(&buffer, &buffersize, filename); + if(!error) error = lodepng_decode_memory(out, w, h, buffer, buffersize, colortype, bitdepth); + myfree(buffer); return error; } -unsigned LodePNG_decode32_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename) +unsigned lodepng_decode32_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename) { - return LodePNG_decode_file(out, w, h, filename, 6, 8); + return lodepng_decode_file(out, w, h, filename, LCT_RGBA, 8); } -unsigned LodePNG_decode24_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename) +unsigned lodepng_decode24_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename) { - return LodePNG_decode_file(out, w, h, filename, 2, 8); + return lodepng_decode_file(out, w, h, filename, LCT_RGB, 8); } #endif /*LODEPNG_COMPILE_DISK*/ -void LodePNG_DecodeSettings_init(LodePNG_DecodeSettings* settings) +void lodepng_decoder_settings_init(LodePNGDecoderSettings* settings) { settings->color_convert = 1; #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - settings->readTextChunks = 1; + settings->read_text_chunks = 1; + settings->remember_unknown_chunks = 0; #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - settings->ignoreCrc = 0; -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS - settings->rememberUnknownChunks = 0; -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ - LodePNG_DecompressSettings_init(&settings->zlibsettings); -} - -void LodePNG_Decoder_init(LodePNG_Decoder* decoder) -{ - LodePNG_DecodeSettings_init(&decoder->settings); - LodePNG_InfoRaw_init(&decoder->infoRaw); - LodePNG_InfoPng_init(&decoder->infoPng); - decoder->error = 1; -} - -void LodePNG_Decoder_cleanup(LodePNG_Decoder* decoder) -{ - LodePNG_InfoRaw_cleanup(&decoder->infoRaw); - LodePNG_InfoPng_cleanup(&decoder->infoPng); -} - -void LodePNG_Decoder_copy(LodePNG_Decoder* dest, const LodePNG_Decoder* source) -{ - LodePNG_Decoder_cleanup(dest); - *dest = *source; - LodePNG_InfoRaw_init(&dest->infoRaw); - LodePNG_InfoPng_init(&dest->infoPng); - dest->error = LodePNG_InfoRaw_copy(&dest->infoRaw, &source->infoRaw); if(dest->error) return; - dest->error = LodePNG_InfoPng_copy(&dest->infoPng, &source->infoPng); if(dest->error) return; + settings->ignore_crc = 0; + lodepng_decompress_settings_init(&settings->zlibsettings); } #endif /*LODEPNG_COMPILE_DECODER*/ +#if defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) + +void lodepng_state_init(LodePNGState* state) +{ +#ifdef LODEPNG_COMPILE_DECODER + lodepng_decoder_settings_init(&state->decoder); +#endif /*LODEPNG_COMPILE_DECODER*/ +#ifdef LODEPNG_COMPILE_ENCODER + lodepng_encoder_settings_init(&state->encoder); +#endif /*LODEPNG_COMPILE_ENCODER*/ + lodepng_color_mode_init(&state->info_raw); + lodepng_info_init(&state->info_png); + state->error = 1; +} + +void lodepng_state_cleanup(LodePNGState* state) +{ + lodepng_color_mode_cleanup(&state->info_raw); + lodepng_info_cleanup(&state->info_png); +} + +void lodepng_state_copy(LodePNGState* dest, const LodePNGState* source) +{ + lodepng_state_cleanup(dest); + *dest = *source; + lodepng_color_mode_init(&dest->info_raw); + lodepng_info_init(&dest->info_png); + dest->error = lodepng_color_mode_copy(&dest->info_raw, &source->info_raw); if(dest->error) return; + dest->error = lodepng_info_copy(&dest->info_png, &source->info_png); if(dest->error) return; +} + +#endif /* defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) */ + #ifdef LODEPNG_COMPILE_ENCODER /* ////////////////////////////////////////////////////////////////////////// */ @@ -4245,8 +4849,7 @@ void LodePNG_Decoder_copy(LodePNG_Decoder* dest, const LodePNG_Decoder* source) /*chunkName must be string of 4 characters*/ static unsigned addChunk(ucvector* out, const char* chunkName, const unsigned char* data, size_t length) { - unsigned error = LodePNG_create_chunk(&out->data, &out->size, (unsigned)length, chunkName, data); - if(error) return error; + CERROR_TRY_RETURN(lodepng_chunk_create(&out->data, &out->size, (unsigned)length, chunkName, data)); out->allocsize = out->size; /*fix the allocsize again*/ return 0; } @@ -4264,20 +4867,20 @@ static void writeSignature(ucvector* out) ucvector_push_back(out, 10); } -static unsigned addChunk_IHDR(ucvector* out, unsigned w, unsigned h, unsigned bitDepth, - unsigned colorType, unsigned interlaceMethod) +static unsigned addChunk_IHDR(ucvector* out, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth, unsigned interlace_method) { unsigned error = 0; ucvector header; ucvector_init(&header); - LodePNG_add32bitInt(&header, w); /*width*/ - LodePNG_add32bitInt(&header, h); /*height*/ - ucvector_push_back(&header, (unsigned char)bitDepth); /*bit depth*/ - ucvector_push_back(&header, (unsigned char)colorType); /*color type*/ + lodepng_add32bitInt(&header, w); /*width*/ + lodepng_add32bitInt(&header, h); /*height*/ + ucvector_push_back(&header, (unsigned char)bitdepth); /*bit depth*/ + ucvector_push_back(&header, (unsigned char)colortype); /*color type*/ ucvector_push_back(&header, 0); /*compression method*/ ucvector_push_back(&header, 0); /*filter method*/ - ucvector_push_back(&header, interlaceMethod); /*interlace method*/ + ucvector_push_back(&header, interlace_method); /*interlace method*/ error = addChunk(out, "IHDR", header.data, header.size); ucvector_cleanup(&header); @@ -4285,7 +4888,7 @@ static unsigned addChunk_IHDR(ucvector* out, unsigned w, unsigned h, unsigned bi return error; } -static unsigned addChunk_PLTE(ucvector* out, const LodePNG_InfoColor* info) +static unsigned addChunk_PLTE(ucvector* out, const LodePNGColorMode* info) { unsigned error = 0; size_t i; @@ -4302,18 +4905,25 @@ static unsigned addChunk_PLTE(ucvector* out, const LodePNG_InfoColor* info) return error; } -static unsigned addChunk_tRNS(ucvector* out, const LodePNG_InfoColor* info) +static unsigned addChunk_tRNS(ucvector* out, const LodePNGColorMode* info) { unsigned error = 0; size_t i; ucvector tRNS; ucvector_init(&tRNS); - if(info->colorType == 3) + if(info->colortype == LCT_PALETTE) { + size_t amount = info->palettesize; + /*the tail of palette values that all have 255 as alpha, does not have to be encoded*/ + for(i = info->palettesize; i > 0; i--) + { + if(info->palette[4 * (i - 1) + 3] == 255) amount--; + else break; + } /*add only alpha channel*/ - for(i = 0; i < info->palettesize; i++) ucvector_push_back(&tRNS, info->palette[4 * i + 3]); + for(i = 0; i < amount; i++) ucvector_push_back(&tRNS, info->palette[4 * i + 3]); } - else if(info->colorType == 0) + else if(info->colortype == LCT_GREY) { if(info->key_defined) { @@ -4321,7 +4931,7 @@ static unsigned addChunk_tRNS(ucvector* out, const LodePNG_InfoColor* info) ucvector_push_back(&tRNS, (unsigned char)(info->key_r % 256)); } } - else if(info->colorType == 2) + else if(info->colortype == LCT_RGB) { if(info->key_defined) { @@ -4341,14 +4951,14 @@ static unsigned addChunk_tRNS(ucvector* out, const LodePNG_InfoColor* info) } static unsigned addChunk_IDAT(ucvector* out, const unsigned char* data, size_t datasize, - LodePNG_CompressSettings* zlibsettings) + LodePNGCompressSettings* zlibsettings) { ucvector zlibdata; unsigned error = 0; /*compress with the Zlib compressor*/ ucvector_init(&zlibdata); - error = LodePNG_zlib_compress(&zlibdata.data, &zlibdata.size, data, datasize, zlibsettings); + error = zlib_compress(&zlibdata.data, &zlibdata.size, data, datasize, zlibsettings); if(!error) error = addChunk(out, "IDAT", zlibdata.data, zlibdata.size); ucvector_cleanup(&zlibdata); @@ -4371,7 +4981,8 @@ static unsigned addChunk_tEXt(ucvector* out, const char* keyword, const char* te ucvector text; ucvector_init(&text); for(i = 0; keyword[i] != 0; i++) ucvector_push_back(&text, (unsigned char)keyword[i]); - ucvector_push_back(&text, 0); + if(i < 1 || i > 79) return 89; /*error: invalid keyword size*/ + ucvector_push_back(&text, 0); /*0 termination char*/ for(i = 0; textstring[i] != 0; i++) ucvector_push_back(&text, (unsigned char)textstring[i]); error = addChunk(out, "tEXt", text.data, text.size); ucvector_cleanup(&text); @@ -4380,7 +4991,7 @@ static unsigned addChunk_tEXt(ucvector* out, const char* keyword, const char* te } static unsigned addChunk_zTXt(ucvector* out, const char* keyword, const char* textstring, - LodePNG_CompressSettings* zlibsettings) + LodePNGCompressSettings* zlibsettings) { unsigned error = 0; ucvector data, compressed; @@ -4389,11 +5000,12 @@ static unsigned addChunk_zTXt(ucvector* out, const char* keyword, const char* te ucvector_init(&data); ucvector_init(&compressed); for(i = 0; keyword[i] != 0; i++) ucvector_push_back(&data, (unsigned char)keyword[i]); - ucvector_push_back(&data, 0); /* 0 termination char*/ + if(i < 1 || i > 79) return 89; /*error: invalid keyword size*/ + ucvector_push_back(&data, 0); /*0 termination char*/ ucvector_push_back(&data, 0); /*compression method: 0*/ - error = LodePNG_zlib_compress(&compressed.data, &compressed.size, - (unsigned char*)textstring, textsize, zlibsettings); + error = zlib_compress(&compressed.data, &compressed.size, + (unsigned char*)textstring, textsize, zlibsettings); if(!error) { for(i = 0; i < compressed.size; i++) ucvector_push_back(&data, compressed.data[i]); @@ -4406,15 +5018,16 @@ static unsigned addChunk_zTXt(ucvector* out, const char* keyword, const char* te } static unsigned addChunk_iTXt(ucvector* out, unsigned compressed, const char* keyword, const char* langtag, - const char* transkey, const char* textstring, LodePNG_CompressSettings* zlibsettings) + const char* transkey, const char* textstring, LodePNGCompressSettings* zlibsettings) { unsigned error = 0; - ucvector data, compressed_data; + ucvector data; size_t i, textsize = strlen(textstring); ucvector_init(&data); for(i = 0; keyword[i] != 0; i++) ucvector_push_back(&data, (unsigned char)keyword[i]); + if(i < 1 || i > 79) return 89; /*error: invalid keyword size*/ ucvector_push_back(&data, 0); /*null termination char*/ ucvector_push_back(&data, compressed ? 1 : 0); /*compression flag*/ ucvector_push_back(&data, 0); /*compression method*/ @@ -4425,14 +5038,15 @@ static unsigned addChunk_iTXt(ucvector* out, unsigned compressed, const char* ke if(compressed) { + ucvector compressed_data; ucvector_init(&compressed_data); - error = LodePNG_zlib_compress(&compressed_data.data, &compressed_data.size, - (unsigned char*)textstring, textsize, zlibsettings); + error = zlib_compress(&compressed_data.data, &compressed_data.size, + (unsigned char*)textstring, textsize, zlibsettings); if(!error) { for(i = 0; i < compressed_data.size; i++) ucvector_push_back(&data, compressed_data.data[i]); - for(i = 0; textstring[i] != 0; i++) ucvector_push_back(&data, (unsigned char)textstring[i]); } + ucvector_cleanup(&compressed_data); } else /*not compressed*/ { @@ -4444,17 +5058,17 @@ static unsigned addChunk_iTXt(ucvector* out, unsigned compressed, const char* ke return error; } -static unsigned addChunk_bKGD(ucvector* out, const LodePNG_InfoPng* info) +static unsigned addChunk_bKGD(ucvector* out, const LodePNGInfo* info) { unsigned error = 0; ucvector bKGD; ucvector_init(&bKGD); - if(info->color.colorType == 0 || info->color.colorType == 4) + if(info->color.colortype == LCT_GREY || info->color.colortype == LCT_GREY_ALPHA) { ucvector_push_back(&bKGD, (unsigned char)(info->background_r / 256)); ucvector_push_back(&bKGD, (unsigned char)(info->background_r % 256)); } - else if(info->color.colorType == 2 || info->color.colorType == 6) + else if(info->color.colortype == LCT_RGB || info->color.colortype == LCT_RGBA) { ucvector_push_back(&bKGD, (unsigned char)(info->background_r / 256)); ucvector_push_back(&bKGD, (unsigned char)(info->background_r % 256)); @@ -4463,7 +5077,7 @@ static unsigned addChunk_bKGD(ucvector* out, const LodePNG_InfoPng* info) ucvector_push_back(&bKGD, (unsigned char)(info->background_b / 256)); ucvector_push_back(&bKGD, (unsigned char)(info->background_b % 256)); } - else if(info->color.colorType == 3) + else if(info->color.colortype == LCT_PALETTE) { ucvector_push_back(&bKGD, (unsigned char)(info->background_r % 256)); /*palette index*/ } @@ -4474,11 +5088,11 @@ static unsigned addChunk_bKGD(ucvector* out, const LodePNG_InfoPng* info) return error; } -static unsigned addChunk_tIME(ucvector* out, const LodePNG_Time* time) +static unsigned addChunk_tIME(ucvector* out, const LodePNGTime* time) { unsigned error = 0; - unsigned char* data = (unsigned char*)malloc(7); - if(!data) return 9948; /*alloc fail*/ + unsigned char* data = (unsigned char*)mymalloc(7); + if(!data) return 83; /*alloc fail*/ data[0] = (unsigned char)(time->year / 256); data[1] = (unsigned char)(time->year % 256); data[2] = time->month; @@ -4487,18 +5101,18 @@ static unsigned addChunk_tIME(ucvector* out, const LodePNG_Time* time) data[5] = time->minute; data[6] = time->second; error = addChunk(out, "tIME", data, 7); - free(data); + myfree(data); return error; } -static unsigned addChunk_pHYs(ucvector* out, const LodePNG_InfoPng* info) +static unsigned addChunk_pHYs(ucvector* out, const LodePNGInfo* info) { unsigned error = 0; ucvector data; ucvector_init(&data); - LodePNG_add32bitInt(&data, info->phys_x); - LodePNG_add32bitInt(&data, info->phys_y); + lodepng_add32bitInt(&data, info->phys_x); + lodepng_add32bitInt(&data, info->phys_y); ucvector_push_back(&data, info->phys_unit); error = addChunk(out, "pHYs", data.data, data.size); @@ -4522,12 +5136,12 @@ static void filterScanline(unsigned char* out, const unsigned char* scanline, co if(prevline) { for(i = 0; i < bytewidth; i++) out[i] = scanline[i]; - for(i = bytewidth; i < length ; i++) out[i] = scanline[i] - scanline[i - bytewidth]; + for(i = bytewidth; i < length; i++) out[i] = scanline[i] - scanline[i - bytewidth]; } else { for(i = 0; i < bytewidth; i++) out[i] = scanline[i]; - for(i = bytewidth; i < length; i++) out[i] = scanline[i] - scanline[i - bytewidth]; + for(i = bytewidth; i < length; i++) out[i] = scanline[i] - scanline[i - bytewidth]; } break; case 2: /*Up*/ @@ -4573,8 +5187,17 @@ static void filterScanline(unsigned char* out, const unsigned char* scanline, co } } +/* log2 approximation. A slight bit faster than std::log. */ +static float flog2(float f) +{ + float result = 0; + while(f > 32) { result += 4; f /= 16; } + while(f > 2) { result++; f /= 2; } + return result + 1.442695f * (f * f * f / 3 - 3 * f * f / 2 + 3 * f - 1.83333f); +} + static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, - const LodePNG_InfoColor* info, const LodePNG_EncodeSettings* settings) + const LodePNGColorMode* info, const LodePNGEncoderSettings* settings) { /* For PNG filter method 0 @@ -4582,7 +5205,7 @@ static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, the scanlines with 1 extra byte per scanline */ - unsigned bpp = LodePNG_InfoColor_getBpp(info); + unsigned bpp = lodepng_get_bpp(info); /*the width of a scanline in bytes, not including the filter type*/ size_t linebytes = (w * bpp + 7) / 8; /*bytewidth is used for filtering, is 1 when bpp < 8, number of bytes per pixel otherwise*/ @@ -4590,89 +5213,155 @@ static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, const unsigned char* prevline = 0; unsigned x, y; unsigned error = 0; + LodePNGFilterStrategy strategy = settings->filter_strategy; + + /* + There is a heuristic called the minimum sum of absolute differences heuristic, suggested by the PNG standard: + * If the image type is Palette, or the bit depth is smaller than 8, then do not filter the image (i.e. + use fixed filtering, with the filter None). + * (The other case) If the image type is Grayscale or RGB (with or without Alpha), and the bit depth is + not smaller than 8, then use adaptive filtering heuristic as follows: independently for each row, apply + all five filters and select the filter that produces the smallest sum of absolute values per row. + This heuristic is used if filter strategy is LFS_MINSUM and filter_palette_zero is true. + + If filter_palette_zero is true and filter_strategy is not LFS_MINSUM, the above heuristic is followed, + but for "the other case", whatever strategy filter_strategy is set to instead of the minimum sum + heuristic is used. + */ + if(settings->filter_palette_zero && + (info->colortype == LCT_PALETTE || info->bitdepth < 8)) strategy = LFS_ZERO; if(bpp == 0) return 31; /*error: invalid color type*/ - if(!settings->bruteForceFilters) + if(strategy == LFS_ZERO) { - /* - There is a heuristic called the minimum sum of absolute differences heuristic, suggested by the PNG standard: - * If the image type is Palette, or the bit depth is smaller than 8, then do not filter the image (i.e. - use fixed filtering, with the filter None). - * (The other case) If the image type is Grayscale or RGB (with or without Alpha), and the bit depth is - not smaller than 8, then use adaptive filtering heuristic as follows: independently for each row, apply - all five filters and select the filter that produces the smallest sum of absolute values per row. - */ - if(info->colorType == 3 || info->bitDepth < 8) /*None filtertype for everything*/ + for(y = 0; y < h; y++) + { + size_t outindex = (1 + linebytes) * y; /*the extra filterbyte added to each row*/ + size_t inindex = linebytes * y; + out[outindex] = 0; /*filter type byte*/ + filterScanline(&out[outindex + 1], &in[inindex], prevline, linebytes, bytewidth, 0); + prevline = &in[inindex]; + } + } + else if(strategy == LFS_MINSUM) + { + /*adaptive filtering*/ + size_t sum[5]; + ucvector attempt[5]; /*five filtering attempts, one for each filter type*/ + size_t smallest = 0; + unsigned type, bestType = 0; + + for(type = 0; type < 5; type++) + { + ucvector_init(&attempt[type]); + if(!ucvector_resize(&attempt[type], linebytes)) return 83; /*alloc fail*/ + } + + if(!error) { for(y = 0; y < h; y++) { - size_t outindex = (1 + linebytes) * y; /*the extra filterbyte added to each row*/ - size_t inindex = linebytes * y; - const unsigned TYPE = 0; - out[outindex] = TYPE; /*filter type byte*/ - filterScanline(&out[outindex + 1], &in[inindex], prevline, linebytes, bytewidth, TYPE); - prevline = &in[inindex]; - } - } - else /*adaptive filtering*/ - { - size_t sum[5]; - ucvector attempt[5]; /*five filtering attempts, one for each filter type*/ - size_t smallest = 0; - unsigned type, bestType = 0; - - for(type = 0; type < 5; type++) ucvector_init(&attempt[type]); - for(type = 0; type < 5; type++) - { - if(!ucvector_resize(&attempt[type], linebytes)) ERROR_BREAK(9949 /*alloc fail*/); - } - - if(!error) - { - for(y = 0; y < h; y++) + /*try the 5 filter types*/ + for(type = 0; type < 5; type++) { - /*try the 5 filter types*/ - for(type = 0; type < 5; type++) - { - filterScanline(attempt[type].data, &in[y * linebytes], prevline, linebytes, bytewidth, type); + filterScanline(attempt[type].data, &in[y * linebytes], prevline, linebytes, bytewidth, type); - /*calculate the sum of the result*/ - sum[type] = 0; - /*note that not all pixels are checked to speed this up while still having probably the best choice*/ - for(x = 0; x < attempt[type].size; x+=3) + /*calculate the sum of the result*/ + sum[type] = 0; + if(type == 0) + { + for(x = 0; x < linebytes; x++) sum[type] += (unsigned char)(attempt[type].data[x]); + } + else + { + for(x = 0; x < linebytes; x++) { /*For differences, each byte should be treated as signed, values above 127 are negative (converted to signed char). Filtertype 0 isn't a difference though, so use unsigned there. This means filtertype 0 is almost never chosen, but that is justified.*/ - if(type == 0) sum[type] += (unsigned char)(attempt[type].data[x]); - else - { - signed char s = (signed char)(attempt[type].data[x]); - sum[type] += s < 0 ? -s : s; - } - } - - /*check if this is smallest sum (or if type == 0 it's the first case so always store the values)*/ - if(type == 0 || sum[type] < smallest) - { - bestType = type; - smallest = sum[type]; + signed char s = (signed char)(attempt[type].data[x]); + sum[type] += s < 0 ? -s : s; } } - prevline = &in[y * linebytes]; + /*check if this is smallest sum (or if type == 0 it's the first case so always store the values)*/ + if(type == 0 || sum[type] < smallest) + { + bestType = type; + smallest = sum[type]; + } + } - /*now fill the out values*/ - out[y * (linebytes + 1)] = bestType; /*the first byte of a scanline will be the filter type*/ - for(x = 0; x < linebytes; x++) out[y * (linebytes + 1) + 1 + x] = attempt[bestType].data[x]; + prevline = &in[y * linebytes]; + + /*now fill the out values*/ + out[y * (linebytes + 1)] = bestType; /*the first byte of a scanline will be the filter type*/ + for(x = 0; x < linebytes; x++) out[y * (linebytes + 1) + 1 + x] = attempt[bestType].data[x]; + } + } + + for(type = 0; type < 5; type++) ucvector_cleanup(&attempt[type]); + } + else if(strategy == LFS_ENTROPY) + { + float sum[5]; + ucvector attempt[5]; /*five filtering attempts, one for each filter type*/ + float smallest = 0; + unsigned type, bestType = 0; + unsigned count[256]; + + for(type = 0; type < 5; type++) + { + ucvector_init(&attempt[type]); + if(!ucvector_resize(&attempt[type], linebytes)) return 83; /*alloc fail*/ + } + + for(y = 0; y < h; y++) + { + /*try the 5 filter types*/ + for(type = 0; type < 5; type++) + { + filterScanline(attempt[type].data, &in[y * linebytes], prevline, linebytes, bytewidth, type); + for(x = 0; x < 256; x++) count[x] = 0; + for(x = 0; x < linebytes; x++) count[attempt[type].data[x]]++; + count[type]++; /*the filter type itself is part of the scanline*/ + sum[type] = 0; + for(x = 0; x < 256; x++) + { + float p = count[x] / (float)(linebytes + 1); + sum[type] += count[x] == 0 ? 0 : flog2(1 / p) * p; + } + /*check if this is smallest sum (or if type == 0 it's the first case so always store the values)*/ + if(type == 0 || sum[type] < smallest) + { + bestType = type; + smallest = sum[type]; } } - for(type = 0; type < 5; type++) ucvector_cleanup(&attempt[type]); + prevline = &in[y * linebytes]; + + /*now fill the out values*/ + out[y * (linebytes + 1)] = bestType; /*the first byte of a scanline will be the filter type*/ + for(x = 0; x < linebytes; x++) out[y * (linebytes + 1) + 1 + x] = attempt[bestType].data[x]; + } + + for(type = 0; type < 5; type++) ucvector_cleanup(&attempt[type]); + } + else if(strategy == LFS_PREDEFINED) + { + for(y = 0; y < h; y++) + { + size_t outindex = (1 + linebytes) * y; /*the extra filterbyte added to each row*/ + size_t inindex = linebytes * y; + unsigned type = settings->predefined_filters[y]; + out[outindex] = type; /*filter type byte*/ + filterScanline(&out[outindex + 1], &in[inindex], prevline, linebytes, bytewidth, type); + prevline = &in[inindex]; } } - else + else if(strategy == LFS_BRUTE_FORCE) { /*brute force filter chooser. deflate the scanline after every filter attempt to see which one deflates best. @@ -4682,12 +5371,16 @@ static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, size_t smallest = 0; unsigned type = 0, bestType = 0; unsigned char* dummy; - LodePNG_CompressSettings zlibsettings = settings->zlibsettings; + LodePNGCompressSettings zlibsettings = settings->zlibsettings; /*use fixed tree on the attempts so that the tree is not adapted to the filtertype on purpose, to simulate the true case where the tree is the same for the whole image. Sometimes it gives better result with dynamic tree anyway. Using the fixed tree sometimes gives worse, but in rare cases better compression. It does make this a bit less slow, so it's worth doing this.*/ zlibsettings.btype = 1; + /*a custom encoder likely doesn't read the btype setting and is optimized for complete PNG + images only, so disable it*/ + zlibsettings.custom_zlib = 0; + zlibsettings.custom_deflate = 0; for(type = 0; type < 5; type++) { ucvector_init(&attempt[type]); @@ -4698,14 +5391,13 @@ static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, for(type = 0; type < 5; type++) { unsigned testsize = attempt[type].size; - /*unsigned testsize = attempt[type].size / 8;*/ /*it already works good enough by testing a part of the row*/ - /*if(testsize == 0) testsize = attempt[type].size;*/ + /*if(testsize > 8) testsize /= 8;*/ /*it already works good enough by testing a part of the row*/ filterScanline(attempt[type].data, &in[y * linebytes], prevline, linebytes, bytewidth, type); size[type] = 0; dummy = 0; - LodePNG_zlib_compress(&dummy, &size[type], attempt[type].data, testsize, &zlibsettings); - free(dummy); + zlib_compress(&dummy, &size[type], attempt[type].data, testsize, &zlibsettings); + myfree(dummy); /*check if this is smallest size (or if type == 0 it's the first case so always store the values)*/ if(type == 0 || size[type] < smallest) { @@ -4719,6 +5411,7 @@ static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, } for(type = 0; type < 5; type++) ucvector_cleanup(&attempt[type]); } + else return 88; /* unknown filter strategy */ return error; } @@ -4745,10 +5438,19 @@ static void addPaddingBits(unsigned char* out, const unsigned char* in, } } +/* +in: non-interlaced image with size w*h +out: the same pixels, but re-ordered according to PNG's Adam7 interlacing, with + no padding bits between scanlines, but between reduced images so that each + reduced image starts at a byte. +bpp: bits per pixel +there are no padding bits, not between scanlines, not between reduced images +in has the following size in bits: w * h * bpp. +out is possibly bigger due to padding bits between reduced images +NOTE: comments about padding bits are only relevant if bpp < 8 +*/ static void Adam7_interlace(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, unsigned bpp) { - /*Note: this function works on image buffers WITHOUT padding bits at end of scanlines with non-multiple-of-8 - bit amounts, only between reduced images is padding*/ unsigned passw[7], passh[7]; size_t filter_passstart[8], padded_passstart[8], passstart[8]; unsigned i; @@ -4799,181 +5501,136 @@ static void Adam7_interlace(unsigned char* out, const unsigned char* in, unsigne /*out must be buffer big enough to contain uncompressed IDAT chunk data, and in must contain the full image. return value is error**/ static unsigned preProcessScanlines(unsigned char** out, size_t* outsize, const unsigned char* in, - const LodePNG_InfoPng* infoPng, const LodePNG_EncodeSettings* settings) + unsigned w, unsigned h, + const LodePNGInfo* info_png, const LodePNGEncoderSettings* settings) { /* This function converts the pure 2D image with the PNG's colortype, into filtered-padded-interlaced data. Steps: *) if no Adam7: 1) add padding bits (= posible extra bits per scanline if bpp < 8) 2) filter *) if adam7: 1) Adam7_interlace 2) 7x add padding bits 3) 7x filter */ - unsigned bpp = LodePNG_InfoColor_getBpp(&infoPng->color); - unsigned w = infoPng->width; - unsigned h = infoPng->height; + unsigned bpp = lodepng_get_bpp(&info_png->color); unsigned error = 0; - if(infoPng->interlaceMethod == 0) + if(info_png->interlace_method == 0) { *outsize = h + (h * ((w * bpp + 7) / 8)); /*image size plus an extra byte per scanline + possible padding bits*/ - *out = (unsigned char*)malloc(*outsize); - if(!(*out) && (*outsize)) error = 9950; /*alloc fail*/ + *out = (unsigned char*)mymalloc(*outsize); + if(!(*out) && (*outsize)) error = 83; /*alloc fail*/ if(!error) { /*non multiple of 8 bits per scanline, padding bits needed per scanline*/ if(bpp < 8 && w * bpp != ((w * bpp + 7) / 8) * 8) { - ucvector padded; - ucvector_init(&padded); - if(!ucvector_resize(&padded, h * ((w * bpp + 7) / 8))) error = 9951; /*alloc fail*/ + unsigned char* padded = (unsigned char*)mymalloc(h * ((w * bpp + 7) / 8)); + if(!padded) error = 83; /*alloc fail*/ if(!error) { - addPaddingBits(padded.data, in, ((w * bpp + 7) / 8) * 8, w * bpp, h); - error = filter(*out, padded.data, w, h, &infoPng->color, settings); + addPaddingBits(padded, in, ((w * bpp + 7) / 8) * 8, w * bpp, h); + error = filter(*out, padded, w, h, &info_png->color, settings); } - ucvector_cleanup(&padded); + myfree(padded); } else { /*we can immediatly filter into the out buffer, no other steps needed*/ - error = filter(*out, in, w, h, &infoPng->color, settings); + error = filter(*out, in, w, h, &info_png->color, settings); } } } - else /*interlaceMethod is 1 (Adam7)*/ + else /*interlace_method is 1 (Adam7)*/ { - unsigned char* adam7 = (unsigned char*)malloc((h * w * bpp + 7) / 8); - if(!adam7 && ((h * w * bpp + 7) / 8)) error = 9952; /*alloc fail*/ + unsigned passw[7], passh[7]; + size_t filter_passstart[8], padded_passstart[8], passstart[8]; + unsigned char* adam7; - while(!error) /*not a real while loop, used to break out to cleanup to avoid a goto*/ + Adam7_getpassvalues(passw, passh, filter_passstart, padded_passstart, passstart, w, h, bpp); + + *outsize = filter_passstart[7]; /*image size plus an extra byte per scanline + possible padding bits*/ + *out = (unsigned char*)mymalloc(*outsize); + if(!(*out)) error = 83; /*alloc fail*/ + + adam7 = (unsigned char*)mymalloc(passstart[7]); + if(!adam7 && passstart[7]) error = 83; /*alloc fail*/ + + if(!error) { - unsigned passw[7], passh[7]; - size_t filter_passstart[8], padded_passstart[8], passstart[8]; unsigned i; - Adam7_getpassvalues(passw, passh, filter_passstart, padded_passstart, passstart, w, h, bpp); - - *outsize = filter_passstart[7]; /*image size plus an extra byte per scanline + possible padding bits*/ - *out = (unsigned char*)malloc(*outsize); - if(!(*out) && (*outsize)) ERROR_BREAK(9953 /*alloc fail*/); - Adam7_interlace(adam7, in, w, h, bpp); - for(i = 0; i < 7; i++) { if(bpp < 8) { - ucvector padded; - ucvector_init(&padded); - if(!ucvector_resize(&padded, h * ((w * bpp + 7) / 8))) error = 9954; /*alloc fail*/ - if(!error) - { - addPaddingBits(&padded.data[padded_passstart[i]], &adam7[passstart[i]], - ((passw[i] * bpp + 7) / 8) * 8, passw[i] * bpp, passh[i]); - error = filter(&(*out)[filter_passstart[i]], &padded.data[padded_passstart[i]], - passw[i], passh[i], &infoPng->color, settings); - } - - ucvector_cleanup(&padded); + unsigned char* padded = (unsigned char*)mymalloc(padded_passstart[i + 1] - padded_passstart[i]); + if(!padded) ERROR_BREAK(83); /*alloc fail*/ + addPaddingBits(padded, &adam7[passstart[i]], + ((passw[i] * bpp + 7) / 8) * 8, passw[i] * bpp, passh[i]); + error = filter(&(*out)[filter_passstart[i]], padded, + passw[i], passh[i], &info_png->color, settings); + myfree(padded); } else { error = filter(&(*out)[filter_passstart[i]], &adam7[padded_passstart[i]], - passw[i], passh[i], &infoPng->color, settings); + passw[i], passh[i], &info_png->color, settings); } - } - break; + if(error) break; + } } - free(adam7); + myfree(adam7); } return error; } -/*palette must have 4 * palettesize bytes allocated, and given in format RGBARGBARGBARGBA...*/ -static unsigned isPaletteFullyOpaque(const unsigned char* palette, size_t palettesize) +/* +palette must have 4 * palettesize bytes allocated, and given in format RGBARGBARGBARGBA... +returns 0 if the palette is opaque, +returns 1 if the palette has a single color with alpha 0 ==> color key +returns 2 if the palette is semi-translucent. +*/ +static unsigned getPaletteTranslucency(const unsigned char* palette, size_t palettesize) { - size_t i; + size_t i, key = 0; + unsigned r = 0, g = 0, b = 0; /*the value of the color with alpha 0, so long as color keying is possible*/ for(i = 0; i < palettesize; i++) { - if(palette[4 * i + 3] != 255) return 0; + if(!key && palette[4 * i + 3] == 0) + { + r = palette[4 * i + 0]; g = palette[4 * i + 1]; b = palette[4 * i + 2]; + key = 1; + i = (size_t)(-1); /*restart from beginning, to detect earlier opaque colors with key's value*/ + } + else if(palette[4 * i + 3] != 255) return 2; + /*when key, no opaque RGB may have key's RGB*/ + else if(key && r == palette[i * 4 + 0] && g == palette[i * 4 + 1] && b == palette[i * 4 + 2]) return 2; } - return 1; + return key; } -/*this function checks if the input image given by the user has no transparent pixels*/ -static unsigned isFullyOpaque(const unsigned char* image, unsigned w, unsigned h, const LodePNG_InfoColor* info) -{ - /*TODO: When the user specified a color key for the input image, then this function must - also check for pixels that are the same as the color key and treat those as transparent.*/ - - unsigned i, numpixels = w * h; - if(info->colorType == 6) - { - if(info->bitDepth == 8) - { - for(i = 0; i < numpixels; i++) - { - if(image[i * 4 + 3] != 255) return 0; - } - } - else - { - for(i = 0; i < numpixels; i++) - { - if(image[i * 8 + 6] != 255 || image[i * 8 + 7] != 255) return 0; - } - } - return 1; /*no single pixel with alpha channel other than 255 found*/ - } - else if(info->colorType == 4) - { - if(info->bitDepth == 8) - { - for(i = 0; i < numpixels; i++) - { - if(image[i * 2 + 1] != 255) return 0; - } - } - else - { - for(i = 0; i < numpixels; i++) - { - if(image[i * 4 + 2] != 255 || image[i * 4 + 3] != 255) return 0; - } - } - return 1; /*no single pixel with alpha channel other than 255 found*/ - } - else if(info->colorType == 3) - { - /*when there's a palette, we could check every pixel for translucency, - but much quicker is to just check the palette*/ - return(isPaletteFullyOpaque(info->palette, info->palettesize)); - } - - return 0; /*color type that isn't supported by this function yet, so assume there is transparency to be safe*/ -} - -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS static unsigned addUnknownChunks(ucvector* out, unsigned char* data, size_t datasize) { unsigned char* inchunk = data; while((size_t)(inchunk - data) < datasize) { - unsigned error = LodePNG_append_chunk(&out->data, &out->size, inchunk); - if(error) return error; /*error: not enough memory*/ + CERROR_TRY_RETURN(lodepng_chunk_append(&out->data, &out->size, inchunk)); out->allocsize = out->size; /*fix the allocsize again*/ - inchunk = LodePNG_chunk_next(inchunk); + inchunk = lodepng_chunk_next(inchunk); } return 0; } -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -void LodePNG_Encoder_encode(LodePNG_Encoder* encoder, unsigned char** out, size_t* outsize, - const unsigned char* image, unsigned w, unsigned h) +unsigned lodepng_encode(unsigned char** out, size_t* outsize, + const unsigned char* image, unsigned w, unsigned h, + LodePNGState* state) { - LodePNG_InfoPng info; + LodePNGInfo info; ucvector outv; unsigned char* data = 0; /*uncompressed version of the IDAT chunk data*/ size_t datasize = 0; @@ -4981,64 +5638,61 @@ void LodePNG_Encoder_encode(LodePNG_Encoder* encoder, unsigned char** out, size_ /*provide some proper output values if error will happen*/ *out = 0; *outsize = 0; - encoder->error = 0; + state->error = 0; - /*UNSAFE copy to avoid having to cleanup! but we will only change primitive parameters, - and not invoke the cleanup function nor touch the palette's buffer so we use it safely*/ - info = encoder->infoPng; - info.width = w; - info.height = h; + lodepng_info_init(&info); + lodepng_info_copy(&info, &state->info_png); - if(encoder->settings.autoLeaveOutAlphaChannel && isFullyOpaque(image, w, h, &encoder->infoRaw.color)) + if((info.color.colortype == LCT_PALETTE || state->encoder.force_palette) + && (info.color.palettesize == 0 || info.color.palettesize > 256)) { - /*go to a color type without alpha channel*/ - if(info.color.colorType == 6) info.color.colorType = 2; - else if(info.color.colorType == 4) info.color.colorType = 0; + state->error = 68; /*invalid palette size, it is only allowed to be 1-256*/ + return state->error; } - if(encoder->settings.zlibsettings.windowSize > 32768) + if(state->encoder.auto_convert != LAC_NO) { - encoder->error = 60; /*error: windowsize larger than allowed*/ - return; + state->error = doAutoChooseColor(&info.color, image, w, h, &state->info_raw, + state->encoder.auto_convert); } - if(encoder->settings.zlibsettings.btype > 2) - { - encoder->error = 61; /*error: unexisting btype*/ - return; - } - if(encoder->infoPng.interlaceMethod > 1) - { - encoder->error = 71; /*error: unexisting interlace mode*/ - return; - } - /*error: unexisting color type given*/ - if((encoder->error = checkColorValidity(info.color.colorType, info.color.bitDepth))) return; - /*error: unexisting color type given*/ - if((encoder->error = checkColorValidity(encoder->infoRaw.color.colorType, encoder->infoRaw.color.bitDepth))) return; + if(state->error) return state->error; - if(!LodePNG_InfoColor_equal(&encoder->infoRaw.color, &info.color)) + if(state->encoder.zlibsettings.windowsize > 32768) + { + CERROR_RETURN_ERROR(state->error, 60); /*error: windowsize larger than allowed*/ + } + if(state->encoder.zlibsettings.btype > 2) + { + CERROR_RETURN_ERROR(state->error, 61); /*error: unexisting btype*/ + } + if(state->info_png.interlace_method > 1) + { + CERROR_RETURN_ERROR(state->error, 71); /*error: unexisting interlace mode*/ + } + + state->error = checkColorValidity(info.color.colortype, info.color.bitdepth); + if(state->error) return state->error; /*error: unexisting color type given*/ + state->error = checkColorValidity(state->info_raw.colortype, state->info_raw.bitdepth); + if(state->error) return state->error; /*error: unexisting color type given*/ + + if(!lodepng_color_mode_equal(&state->info_raw, &info.color)) { unsigned char* converted; - size_t size = (w * h * LodePNG_InfoColor_getBpp(&info.color) + 7) / 8; + size_t size = (w * h * lodepng_get_bpp(&info.color) + 7) / 8; - if((info.color.colorType != 6 && info.color.colorType != 2) || (info.color.bitDepth != 8)) + converted = (unsigned char*)mymalloc(size); + if(!converted && size) state->error = 83; /*alloc fail*/ + if(!state->error) { - encoder->error = 59; /*for the output image, only these types are supported*/ - return; + state->error = lodepng_convert(converted, image, &info.color, &state->info_raw, w, h); } - converted = (unsigned char*)malloc(size); - if(!converted && size) encoder->error = 9955; /*alloc fail*/ - if(!encoder->error) - { - encoder->error = LodePNG_convert(converted, image, &info.color, &encoder->infoRaw.color, w, h); - } - if(!encoder->error) preProcessScanlines(&data, &datasize, converted, &info, &encoder->settings); - free(converted); + if(!state->error) preProcessScanlines(&data, &datasize, converted, w, h, &info, &state->encoder); + myfree(converted); } - else preProcessScanlines(&data, &datasize, image, &info, &encoder->settings); + else preProcessScanlines(&data, &datasize, image, w, h, &info, &state->encoder); ucvector_init(&outv); - while(!encoder->error) /*while only executed once, to break on error*/ + while(!state->error) /*while only executed once, to break on error*/ { #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS size_t i; @@ -5046,40 +5700,30 @@ void LodePNG_Encoder_encode(LodePNG_Encoder* encoder, unsigned char** out, size_ /*write signature and chunks*/ writeSignature(&outv); /*IHDR*/ - addChunk_IHDR(&outv, w, h, info.color.bitDepth, info.color.colorType, info.interlaceMethod); -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS + addChunk_IHDR(&outv, w, h, info.color.colortype, info.color.bitdepth, info.interlace_method); +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS /*unknown chunks between IHDR and PLTE*/ - if(info.unknown_chunks.data[0]) + if(info.unknown_chunks_data[0]) { - encoder->error = addUnknownChunks(&outv, info.unknown_chunks.data[0], info.unknown_chunks.datasize[0]); - if(encoder->error) break; + state->error = addUnknownChunks(&outv, info.unknown_chunks_data[0], info.unknown_chunks_size[0]); + if(state->error) break; } -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ /*PLTE*/ - if(info.color.colorType == 3) + if(info.color.colortype == LCT_PALETTE) { - if(info.color.palettesize == 0 || info.color.palettesize > 256) - { - encoder->error = 68; /*invalid palette size*/ - break; - } addChunk_PLTE(&outv, &info.color); } - if(encoder->settings.force_palette && (info.color.colorType == 2 || info.color.colorType == 6)) + if(state->encoder.force_palette && (info.color.colortype == LCT_RGB || info.color.colortype == LCT_RGBA)) { - if(info.color.palettesize == 0 || info.color.palettesize > 256) - { - encoder->error = 68; /*invalid palette size*/ - break; - } addChunk_PLTE(&outv, &info.color); } /*tRNS*/ - if(info.color.colorType == 3 && !isPaletteFullyOpaque(info.color.palette, info.color.palettesize)) + if(info.color.colortype == LCT_PALETTE && getPaletteTranslucency(info.color.palette, info.color.palettesize) != 0) { addChunk_tRNS(&outv, &info.color); } - if((info.color.colorType == 0 || info.color.colorType == 2) && info.color.key_defined) + if((info.color.colortype == LCT_GREY || info.color.colortype == LCT_RGB) && info.color.key_defined) { addChunk_tRNS(&outv, &info.color); } @@ -5088,46 +5732,45 @@ void LodePNG_Encoder_encode(LodePNG_Encoder* encoder, unsigned char** out, size_ if(info.background_defined) addChunk_bKGD(&outv, &info); /*pHYs (must come before the IDAT chunks)*/ if(info.phys_defined) addChunk_pHYs(&outv, &info); -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS + /*unknown chunks between PLTE and IDAT*/ - if(info.unknown_chunks.data[1]) + if(info.unknown_chunks_data[1]) { - encoder->error = addUnknownChunks(&outv, info.unknown_chunks.data[1], info.unknown_chunks.datasize[1]); - if(encoder->error) break; + state->error = addUnknownChunks(&outv, info.unknown_chunks_data[1], info.unknown_chunks_size[1]); + if(state->error) break; } -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ /*IDAT (multiple IDAT chunks must be consecutive)*/ - encoder->error = addChunk_IDAT(&outv, data, datasize, &encoder->settings.zlibsettings); - if(encoder->error) break; + state->error = addChunk_IDAT(&outv, data, datasize, &state->encoder.zlibsettings); + if(state->error) break; #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS /*tIME*/ if(info.time_defined) addChunk_tIME(&outv, &info.time); /*tEXt and/or zTXt*/ - for(i = 0; i < info.text.num; i++) + for(i = 0; i < info.text_num; i++) { - if(strlen(info.text.keys[i]) > 79) + if(strlen(info.text_keys[i]) > 79) { - encoder->error = 66; /*text chunk too large*/ + state->error = 66; /*text chunk too large*/ break; } - if(strlen(info.text.keys[i]) < 1) + if(strlen(info.text_keys[i]) < 1) { - encoder->error = 67; /*text chunk too small*/ + state->error = 67; /*text chunk too small*/ break; } - if(encoder->settings.text_compression) - addChunk_zTXt(&outv, info.text.keys[i], info.text.strings[i], &encoder->settings.zlibsettings); + if(state->encoder.text_compression) + addChunk_zTXt(&outv, info.text_keys[i], info.text_strings[i], &state->encoder.zlibsettings); else - addChunk_tEXt(&outv, info.text.keys[i], info.text.strings[i]); + addChunk_tEXt(&outv, info.text_keys[i], info.text_strings[i]); } /*LodePNG version id in text chunk*/ - if(encoder->settings.add_id) + if(state->encoder.add_id) { unsigned alread_added_id_text = 0; - for(i = 0; i < info.text.num; i++) + for(i = 0; i < info.text_num; i++) { - if(!strcmp(info.text.keys[i], "LodePNG")) + if(!strcmp(info.text_keys[i], "LodePNG")) { alread_added_id_text = 1; break; @@ -5137,141 +5780,117 @@ void LodePNG_Encoder_encode(LodePNG_Encoder* encoder, unsigned char** out, size_ addChunk_tEXt(&outv, "LodePNG", VERSION_STRING); /*it's shorter as tEXt than as zTXt chunk*/ } /*iTXt*/ - for(i = 0; i < info.itext.num; i++) + for(i = 0; i < info.itext_num; i++) { - if(strlen(info.itext.keys[i]) > 79) + if(strlen(info.itext_keys[i]) > 79) { - encoder->error = 66; /*text chunk too large*/ + state->error = 66; /*text chunk too large*/ break; } - if(strlen(info.itext.keys[i]) < 1) + if(strlen(info.itext_keys[i]) < 1) { - encoder->error = 67; /*text chunk too small*/ + state->error = 67; /*text chunk too small*/ break; } - addChunk_iTXt(&outv, encoder->settings.text_compression, - info.itext.keys[i], info.itext.langtags[i], info.itext.transkeys[i], info.itext.strings[i], - &encoder->settings.zlibsettings); + addChunk_iTXt(&outv, state->encoder.text_compression, + info.itext_keys[i], info.itext_langtags[i], info.itext_transkeys[i], info.itext_strings[i], + &state->encoder.zlibsettings); + } + + /*unknown chunks between IDAT and IEND*/ + if(info.unknown_chunks_data[2]) + { + state->error = addUnknownChunks(&outv, info.unknown_chunks_data[2], info.unknown_chunks_size[2]); + if(state->error) break; } #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS - /*unknown chunks between IDAT and IEND*/ - if(info.unknown_chunks.data[2]) - { - encoder->error = addUnknownChunks(&outv, info.unknown_chunks.data[2], info.unknown_chunks.datasize[2]); - if(encoder->error) break; - } -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ /*IEND*/ addChunk_IEND(&outv); break; /*this isn't really a while loop; no error happened so break out now!*/ } - free(data); + lodepng_info_cleanup(&info); + myfree(data); /*instead of cleaning the vector up, give it to the output*/ *out = outv.data; *outsize = outv.size; + + return state->error; } -unsigned LodePNG_encode(unsigned char** out, size_t* outsize, const unsigned char* image, - unsigned w, unsigned h, unsigned colorType, unsigned bitDepth) +unsigned lodepng_encode_memory(unsigned char** out, size_t* outsize, const unsigned char* image, + unsigned w, unsigned h, LodePNGColorType colortype, unsigned bitdepth) { unsigned error; - LodePNG_Encoder encoder; - LodePNG_Encoder_init(&encoder); - encoder.infoRaw.color.colorType = colorType; - encoder.infoRaw.color.bitDepth = bitDepth; - encoder.infoPng.color.colorType = colorType; - encoder.infoPng.color.bitDepth = bitDepth; - LodePNG_Encoder_encode(&encoder, out, outsize, image, w, h); - error = encoder.error; - LodePNG_Encoder_cleanup(&encoder); + LodePNGState state; + lodepng_state_init(&state); + state.info_raw.colortype = colortype; + state.info_raw.bitdepth = bitdepth; + state.info_png.color.colortype = colortype; + state.info_png.color.bitdepth = bitdepth; + lodepng_encode(out, outsize, image, w, h, &state); + error = state.error; + lodepng_state_cleanup(&state); return error; } -unsigned LodePNG_encode32(unsigned char** out, size_t* outsize, const unsigned char* image, unsigned w, unsigned h) +unsigned lodepng_encode32(unsigned char** out, size_t* outsize, const unsigned char* image, unsigned w, unsigned h) { - return LodePNG_encode(out, outsize, image, w, h, 6, 8); + return lodepng_encode_memory(out, outsize, image, w, h, LCT_RGBA, 8); } -unsigned LodePNG_encode24(unsigned char** out, size_t* outsize, const unsigned char* image, unsigned w, unsigned h) +unsigned lodepng_encode24(unsigned char** out, size_t* outsize, const unsigned char* image, unsigned w, unsigned h) { - return LodePNG_encode(out, outsize, image, w, h, 2, 8); + return lodepng_encode_memory(out, outsize, image, w, h, LCT_RGB, 8); } #ifdef LODEPNG_COMPILE_DISK -unsigned LodePNG_encode_file(const char* filename, const unsigned char* image, unsigned w, unsigned h, - unsigned colorType, unsigned bitDepth) +unsigned lodepng_encode_file(const char* filename, const unsigned char* image, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth) { unsigned char* buffer; size_t buffersize; - unsigned error = LodePNG_encode(&buffer, &buffersize, image, w, h, colorType, bitDepth); - if(!error) error = LodePNG_saveFile(buffer, buffersize, filename); - free(buffer); + unsigned error = lodepng_encode_memory(&buffer, &buffersize, image, w, h, colortype, bitdepth); + if(!error) error = lodepng_save_file(buffer, buffersize, filename); + myfree(buffer); return error; } -unsigned LodePNG_encode32_file(const char* filename, const unsigned char* image, unsigned w, unsigned h) +unsigned lodepng_encode32_file(const char* filename, const unsigned char* image, unsigned w, unsigned h) { - return LodePNG_encode_file(filename, image, w, h, 6, 8); + return lodepng_encode_file(filename, image, w, h, LCT_RGBA, 8); } -unsigned LodePNG_encode24_file(const char* filename, const unsigned char* image, unsigned w, unsigned h) +unsigned lodepng_encode24_file(const char* filename, const unsigned char* image, unsigned w, unsigned h) { - return LodePNG_encode_file(filename, image, w, h, 2, 8); + return lodepng_encode_file(filename, image, w, h, LCT_RGB, 8); } #endif /*LODEPNG_COMPILE_DISK*/ -void LodePNG_EncodeSettings_init(LodePNG_EncodeSettings* settings) +void lodepng_encoder_settings_init(LodePNGEncoderSettings* settings) { - LodePNG_CompressSettings_init(&settings->zlibsettings); - settings->bruteForceFilters = 0; - settings->autoLeaveOutAlphaChannel = 1; + lodepng_compress_settings_init(&settings->zlibsettings); + settings->filter_palette_zero = 1; + settings->filter_strategy = LFS_MINSUM; + settings->auto_convert = LAC_AUTO; settings->force_palette = 0; + settings->predefined_filters = 0; #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - settings->add_id = 1; - settings->text_compression = 0; + settings->add_id = 0; + settings->text_compression = 1; #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ } -void LodePNG_Encoder_init(LodePNG_Encoder* encoder) -{ - LodePNG_EncodeSettings_init(&encoder->settings); - LodePNG_InfoPng_init(&encoder->infoPng); - LodePNG_InfoRaw_init(&encoder->infoRaw); - encoder->error = 1; -} - -void LodePNG_Encoder_cleanup(LodePNG_Encoder* encoder) -{ - LodePNG_InfoPng_cleanup(&encoder->infoPng); - LodePNG_InfoRaw_cleanup(&encoder->infoRaw); -} - -void LodePNG_Encoder_copy(LodePNG_Encoder* dest, const LodePNG_Encoder* source) -{ - LodePNG_Encoder_cleanup(dest); - *dest = *source; - LodePNG_InfoPng_init(&dest->infoPng); - LodePNG_InfoRaw_init(&dest->infoRaw); - dest->error = LodePNG_InfoPng_copy(&dest->infoPng, &source->infoPng); - if(dest->error) return; - dest->error = LodePNG_InfoRaw_copy(&dest->infoRaw, &source->infoRaw); - if(dest->error) return; -} - #endif /*LODEPNG_COMPILE_ENCODER*/ - #endif /*LODEPNG_COMPILE_PNG*/ #ifdef LODEPNG_COMPILE_ERROR_TEXT - /* This returns the description of a numerical error code in English. This is also the documentation of all the error codes. */ -const char* LodePNG_error_text(unsigned code) +const char* lodepng_error_text(unsigned code) { switch(code) { @@ -5288,13 +5907,11 @@ const char* LodePNG_error_text(unsigned code) case 19: return "end of out buffer memory reached while inflating"; case 20: return "invalid deflate block BTYPE encountered while decoding"; case 21: return "NLEN is not ones complement of LEN in a deflate block"; - /*end of out buffer memory reached while inflating: This can happen if the inflated deflate data is longer than the amount of bytes required to fill up all the pixels of the image, given the color depth and image dimensions. Something that doesn't happen in a normal, well encoded, PNG image.*/ case 22: return "end of out buffer memory reached while inflating"; - case 23: return "end of in buffer memory reached while inflating"; case 24: return "invalid FCHECK in zlib header"; case 25: return "invalid compression method in zlib header"; @@ -5330,23 +5947,22 @@ const char* LodePNG_error_text(unsigned code) case 51: return "jumped past memory while inflating huffman block"; case 52: return "jumped past memory while inflating"; case 53: return "size of zlib data too small"; - + case 54: return "repeat symbol in tree while there was no value symbol yet"; /*jumped past tree while generating huffman tree, this could be when the tree will have more leaves than symbols after generating it out of the given lenghts. They call this an oversubscribed dynamic bit lengths tree in zlib.*/ case 55: return "jumped past tree while generating huffman tree"; - - case 56: return "given output image colorType or bitDepth not supported for color conversion"; + case 56: return "given output image colortype or bitdepth not supported for color conversion"; case 57: return "invalid CRC encountered (checking CRC can be disabled)"; case 58: return "invalid ADLER32 encountered (checking ADLER32 can be disabled)"; - case 59: return "conversion to unexisting color mode or color mode conversion not supported"; + case 59: return "requested color conversion not supported"; case 60: return "invalid window size given in the settings of the encoder (must be 0-32768)"; case 61: return "invalid BTYPE given in the settings of the encoder (only 0, 1 and 2 are allowed)"; /*LodePNG leaves the choice of RGB to greyscale conversion formula to the user.*/ - case 62: return "conversion from RGB to greyscale not supported"; + case 62: return "conversion from color to greyscale not supported"; case 63: return "length of a chunk too long, max allowed for PNG is 2147483647 bytes per chunk"; /*(2^31-1)*/ /*this would result in the inability of a deflated block to ever contain an end code. It must be at least 1.*/ - case 64: return "the length of the END symbol 256 in the Huffman tree is 0"; + case 64: return "the length of the END symbol 256 in the Huffman tree is 0"; case 66: return "the length of a text chunk keyword given to the encoder is longer than the maximum of 79 bytes"; case 67: return "the length of a text chunk keyword given to the encoder is smaller than the minimum of 1 byte"; case 68: return "tried to encode a PLTE chunk with a palette that has less than 1 or more than 256 colors"; @@ -5363,435 +5979,248 @@ const char* LodePNG_error_text(unsigned code) case 79: return "failed to open file for writing"; case 80: return "tried creating a tree of 0 symbols"; case 81: return "lazy matching at pos 0 is impossible"; - default: ; /*nothing to do here, checks for other error values are below*/ + case 82: return "color conversion to palette requested while a color isn't in palette"; + case 83: return "memory allocation failed"; + case 84: return "given image too small to contain all pixels to be encoded"; + case 85: return "internal color conversion bug"; + case 86: return "impossible offset in lz77 encoding (internal bug)"; + case 87: return "must provide custom zlib function pointer if LODEPNG_COMPILE_ZLIB is not defined"; + case 88: return "invalid filter strategy given for LodePNGEncoderSettings.filter_strategy"; + case 89: return "text chunk keyword too short or long: must have size 1-79"; } - - if(code >= 9900 && code <= 9999) return "memory allocation failed"; - return "unknown error code"; } - #endif /*LODEPNG_COMPILE_ERROR_TEXT*/ /* ////////////////////////////////////////////////////////////////////////// */ /* ////////////////////////////////////////////////////////////////////////// */ -/* // End of PNG related code. Begin of C++ wrapper. // */ +/* // C++ Wrapper // */ /* ////////////////////////////////////////////////////////////////////////// */ /* ////////////////////////////////////////////////////////////////////////// */ -#ifdef __cplusplus -namespace LodePNG + +#ifdef LODEPNG_COMPILE_CPP +namespace lodepng { + #ifdef LODEPNG_COMPILE_DISK - void loadFile(std::vector& buffer, const std::string& filename) - { - std::ifstream file(filename.c_str(), std::ios::in|std::ios::binary|std::ios::ate); +void load_file(std::vector& buffer, const std::string& filename) +{ + std::ifstream file(filename.c_str(), std::ios::in|std::ios::binary|std::ios::ate); - /*get filesize*/ - std::streamsize size = 0; - if(file.seekg(0, std::ios::end).good()) size = file.tellg(); - if(file.seekg(0, std::ios::beg).good()) size -= file.tellg(); + /*get filesize*/ + std::streamsize size = 0; + if(file.seekg(0, std::ios::end).good()) size = file.tellg(); + if(file.seekg(0, std::ios::beg).good()) size -= file.tellg(); - /*read contents of the file into the vector*/ - buffer.resize(size_t(size)); - if(size > 0) file.read((char*)(&buffer[0]), size); - } + /*read contents of the file into the vector*/ + buffer.resize(size_t(size)); + if(size > 0) file.read((char*)(&buffer[0]), size); +} - /*write given buffer to the file, overwriting the file, it doesn't append to it.*/ - void saveFile(const std::vector& buffer, const std::string& filename) - { - std::ofstream file(filename.c_str(), std::ios::out|std::ios::binary); - file.write(buffer.empty() ? 0 : (char*)&buffer[0], std::streamsize(buffer.size())); - } +/*write given buffer to the file, overwriting the file, it doesn't append to it.*/ +void save_file(const std::vector& buffer, const std::string& filename) +{ + std::ofstream file(filename.c_str(), std::ios::out|std::ios::binary); + file.write(buffer.empty() ? 0 : (char*)&buffer[0], std::streamsize(buffer.size())); +} #endif //LODEPNG_COMPILE_DISK -/* ////////////////////////////////////////////////////////////////////////// */ - #ifdef LODEPNG_COMPILE_ZLIB #ifdef LODEPNG_COMPILE_DECODER - unsigned decompress(std::vector& out, const unsigned char* in, size_t insize, - const LodePNG_DecompressSettings& settings) +unsigned decompress(std::vector& out, const unsigned char* in, size_t insize, + const LodePNGDecompressSettings& settings) +{ + unsigned char* buffer = 0; + size_t buffersize = 0; + unsigned error = zlib_decompress(&buffer, &buffersize, in, insize, &settings); + if(buffer) { - unsigned char* buffer = 0; - size_t buffersize = 0; - unsigned error = LodePNG_zlib_decompress(&buffer, &buffersize, in, insize, &settings); - if(buffer) - { - out.insert(out.end(), &buffer[0], &buffer[buffersize]); - free(buffer); - } - return error; + out.insert(out.end(), &buffer[0], &buffer[buffersize]); + myfree(buffer); } + return error; +} - unsigned decompress(std::vector& out, const std::vector& in, - const LodePNG_DecompressSettings& settings) - { - return decompress(out, in.empty() ? 0 : &in[0], in.size(), settings); - } +unsigned decompress(std::vector& out, const std::vector& in, + const LodePNGDecompressSettings& settings) +{ + return decompress(out, in.empty() ? 0 : &in[0], in.size(), settings); +} #endif //LODEPNG_COMPILE_DECODER #ifdef LODEPNG_COMPILE_ENCODER - unsigned compress(std::vector& out, const unsigned char* in, size_t insize, - const LodePNG_CompressSettings& settings) +unsigned compress(std::vector& out, const unsigned char* in, size_t insize, + const LodePNGCompressSettings& settings) +{ + unsigned char* buffer = 0; + size_t buffersize = 0; + unsigned error = zlib_compress(&buffer, &buffersize, in, insize, &settings); + if(buffer) { - unsigned char* buffer = 0; - size_t buffersize = 0; - unsigned error = LodePNG_zlib_compress(&buffer, &buffersize, in, insize, &settings); - if(buffer) - { - out.insert(out.end(), &buffer[0], &buffer[buffersize]); - free(buffer); - } - return error; + out.insert(out.end(), &buffer[0], &buffer[buffersize]); + myfree(buffer); } + return error; +} - unsigned compress(std::vector& out, const std::vector& in, - const LodePNG_CompressSettings& settings) - { - return compress(out, in.empty() ? 0 : &in[0], in.size(), settings); - } +unsigned compress(std::vector& out, const std::vector& in, + const LodePNGCompressSettings& settings) +{ + return compress(out, in.empty() ? 0 : &in[0], in.size(), settings); +} #endif //LODEPNG_COMPILE_ENCODER #endif //LODEPNG_COMPILE_ZLIB + #ifdef LODEPNG_COMPILE_PNG -#ifdef LODEPNG_COMPILE_DECODER - Decoder::Decoder() - { - LodePNG_Decoder_init(this); - } - Decoder::~Decoder() - { - LodePNG_Decoder_cleanup(this); - } +State::State() +{ + lodepng_state_init(this); +} - void Decoder::operator=(const LodePNG_Decoder& other) - { - LodePNG_Decoder_copy(this, &other); - } +State::State(const State& other) +{ + lodepng_state_init(this); + lodepng_state_copy(this, &other); +} - bool Decoder::hasError() const - { - return error != 0; - } - unsigned Decoder::getError() const - { - return error; - } +State::~State() +{ + lodepng_state_cleanup(this); +} - unsigned Decoder::getWidth() const - { - return infoPng.width; - } - - unsigned Decoder::getHeight() const - { - return infoPng.height; - } - - unsigned Decoder::getBpp() - { - return LodePNG_InfoColor_getBpp(&infoPng.color); - } - - unsigned Decoder::getChannels() - { - return LodePNG_InfoColor_getChannels(&infoPng.color); - } - - unsigned Decoder::isGreyscaleType() - { - return LodePNG_InfoColor_isGreyscaleType(&infoPng.color); - } - - unsigned Decoder::isAlphaType() - { - return LodePNG_InfoColor_isAlphaType(&infoPng.color); - } - - void Decoder::decode(std::vector& out, const unsigned char* in, size_t insize) - { - unsigned char* buffer; - size_t buffersize; - LodePNG_Decoder_decode(this, &buffer, &buffersize, in, insize); - if(buffer) - { - out.insert(out.end(), &buffer[0], &buffer[buffersize]); - free(buffer); - } - } - - void Decoder::decode(std::vector& out, const std::vector& in) - { - decode(out, in.empty() ? 0 : &in[0], in.size()); - } - - void Decoder::inspect(const unsigned char* in, size_t insize) - { - LodePNG_Decoder_inspect(this, in, insize); - } - - void Decoder::inspect(const std::vector& in) - { - inspect(in.empty() ? 0 : &in[0], in.size()); - } - - const LodePNG_DecodeSettings& Decoder::getSettings() const - { - return settings; - } - - LodePNG_DecodeSettings& Decoder::getSettings() - { - return settings; - } - - void Decoder::setSettings(const LodePNG_DecodeSettings& settings) - { - this->settings = settings; - } - - const LodePNG_InfoPng& Decoder::getInfoPng() const - { - return infoPng; - } - - LodePNG_InfoPng& Decoder::getInfoPng() - { - return infoPng; - } - - void Decoder::setInfoPng(const LodePNG_InfoPng& info) - { - error = LodePNG_InfoPng_copy(&this->infoPng, &info); - } - - void Decoder::swapInfoPng(LodePNG_InfoPng& info) - { - LodePNG_InfoPng_swap(&this->infoPng, &info); - } - - const LodePNG_InfoRaw& Decoder::getInfoRaw() const - { - return infoRaw; - } - - LodePNG_InfoRaw& Decoder::getInfoRaw() - { - return infoRaw; - } - - void Decoder::setInfoRaw(const LodePNG_InfoRaw& info) - { - error = LodePNG_InfoRaw_copy(&this->infoRaw, &info); - } - -#endif //LODEPNG_COMPILE_DECODER - - /* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_ENCODER - - Encoder::Encoder() - { - LodePNG_Encoder_init(this); - } - - Encoder::~Encoder() - { - LodePNG_Encoder_cleanup(this); - } - - void Encoder::operator=(const LodePNG_Encoder& other) - { - LodePNG_Encoder_copy(this, &other); - } - - bool Encoder::hasError() const - { - return error != 0; - } - - unsigned Encoder::getError() const - { - return error; - } - - void Encoder::encode(std::vector& out, const unsigned char* image, unsigned w, unsigned h) - { - unsigned char* buffer; - size_t buffersize; - LodePNG_Encoder_encode(this, &buffer, &buffersize, image, w, h); - if(buffer) - { - out.insert(out.end(), &buffer[0], &buffer[buffersize]); - free(buffer); - } - } - - void Encoder::encode(std::vector& out, const std::vector& image, - unsigned w, unsigned h) - { - encode(out, image.empty() ? 0 : &image[0], w, h); - } - - void Encoder::clearPalette() - { - LodePNG_InfoColor_clearPalette(&infoPng.color); - } - - void Encoder::addPalette(unsigned char r, unsigned char g, unsigned char b, unsigned char a) - { - error = LodePNG_InfoColor_addPalette(&infoPng.color, r, g, b, a); - } - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - void Encoder::clearText() - { - LodePNG_Text_clear(&infoPng.text); - } - - void Encoder::addText(const std::string& key, const std::string& str) - { - error = LodePNG_Text_add(&infoPng.text, key.c_str(), str.c_str()); - } - - void Encoder::clearIText() - { - LodePNG_IText_clear(&infoPng.itext); - } - - void Encoder::addIText(const std::string& key, const std::string& langtag, - const std::string& transkey, const std::string& str) - { - error = LodePNG_IText_add(&infoPng.itext, key.c_str(), langtag.c_str(), transkey.c_str(), str.c_str()); - } -#endif //LODEPNG_COMPILE_ANCILLARY_CHUNKS - - const LodePNG_EncodeSettings& Encoder::getSettings() const - { - return settings; - } - - LodePNG_EncodeSettings& Encoder::getSettings() - { - return settings; - } - - void Encoder::setSettings(const LodePNG_EncodeSettings& settings) - { - this->settings = settings; - } - - const LodePNG_InfoPng& Encoder::getInfoPng() const - { - return infoPng; - } - - LodePNG_InfoPng& Encoder::getInfoPng() - { - return infoPng; - } - - void Encoder::setInfoPng(const LodePNG_InfoPng& info) - { - error = LodePNG_InfoPng_copy(&this->infoPng, &info); - } - - void Encoder::swapInfoPng(LodePNG_InfoPng& info) - { - LodePNG_InfoPng_swap(&this->infoPng, &info); - } - - const LodePNG_InfoRaw& Encoder::getInfoRaw() const - { - return infoRaw; - } - - LodePNG_InfoRaw& Encoder::getInfoRaw() - { - return infoRaw; - } - - void Encoder::setInfoRaw(const LodePNG_InfoRaw& info) - { - error = LodePNG_InfoRaw_copy(&this->infoRaw, &info); - } -#endif //LODEPNG_COMPILE_ENCODER - - /* ////////////////////////////////////////////////////////////////////////// */ +State& State::operator=(const State& other) +{ + lodepng_state_copy(this, &other); + return *this; +} #ifdef LODEPNG_COMPILE_DECODER - unsigned decode(std::vector& out, unsigned& w, unsigned& h, const unsigned char* in, - size_t insize, unsigned colorType, unsigned bitDepth) +unsigned decode(std::vector& out, unsigned& w, unsigned& h, const unsigned char* in, + size_t insize, LodePNGColorType colortype, unsigned bitdepth) +{ + unsigned char* buffer; + unsigned error = lodepng_decode_memory(&buffer, &w, &h, in, insize, colortype, bitdepth); + if(buffer && !error) { - Decoder decoder; - decoder.getInfoRaw().color.colorType = colorType; - decoder.getInfoRaw().color.bitDepth = bitDepth; - decoder.decode(out, in, insize); - w = decoder.getWidth(); - h = decoder.getHeight(); - return decoder.getError(); + State state; + state.info_raw.colortype = colortype; + state.info_raw.bitdepth = bitdepth; + size_t buffersize = lodepng_get_raw_size(w, h, &state.info_raw); + out.insert(out.end(), &buffer[0], &buffer[buffersize]); + myfree(buffer); } + return error; +} - unsigned decode(std::vector& out, unsigned& w, unsigned& h, - const std::vector& in, unsigned colorType, unsigned bitDepth) +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + const std::vector& in, LodePNGColorType colortype, unsigned bitdepth) +{ + return decode(out, w, h, in.empty() ? 0 : &in[0], (unsigned)in.size(), colortype, bitdepth); +} + +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + State& state, + const unsigned char* in, size_t insize) +{ + unsigned char* buffer; + unsigned error = lodepng_decode(&buffer, &w, &h, &state, in, insize); + if(buffer && !error) { - return decode(out, w, h, in.empty() ? 0 : &in[0], (unsigned)in.size(), colorType, bitDepth); + size_t buffersize = lodepng_get_raw_size(w, h, &state.info_raw); + out.insert(out.end(), &buffer[0], &buffer[buffersize]); + myfree(buffer); } + return error; +} + +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + State& state, + const std::vector& in) +{ + return decode(out, w, h, state, in.empty() ? 0 : &in[0], in.size()); +} #ifdef LODEPNG_COMPILE_DISK - unsigned decode(std::vector& out, unsigned& w, unsigned& h, const std::string& filename, - unsigned colorType, unsigned bitDepth) - { - std::vector buffer; - loadFile(buffer, filename); - return decode(out, w, h, buffer, colorType, bitDepth); - } +unsigned decode(std::vector& out, unsigned& w, unsigned& h, const std::string& filename, + LodePNGColorType colortype, unsigned bitdepth) +{ + std::vector buffer; + load_file(buffer, filename); + return decode(out, w, h, buffer, colortype, bitdepth); +} #endif //LODEPNG_COMPILE_DECODER #endif //LODEPNG_COMPILE_DISK #ifdef LODEPNG_COMPILE_ENCODER - - unsigned encode(std::vector& out, const unsigned char* in, unsigned w, unsigned h, - unsigned colorType, unsigned bitDepth) +unsigned encode(std::vector& out, const unsigned char* in, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth) +{ + unsigned char* buffer; + size_t buffersize; + unsigned error = lodepng_encode_memory(&buffer, &buffersize, in, w, h, colortype, bitdepth); + if(buffer) { - Encoder encoder; - encoder.getInfoRaw().color.colorType = colorType; - encoder.getInfoRaw().color.bitDepth = bitDepth; - encoder.getInfoPng().color.colorType = colorType; - encoder.getInfoPng().color.bitDepth = bitDepth; - encoder.encode(out, in, w, h); - return encoder.getError(); + out.insert(out.end(), &buffer[0], &buffer[buffersize]); + myfree(buffer); } + return error; +} - unsigned encode(std::vector& out, const std::vector& in, unsigned w, unsigned h, - unsigned colorType, unsigned bitDepth) +unsigned encode(std::vector& out, + const std::vector& in, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth) +{ + if(lodepng_get_raw_size_lct(w, h, colortype, bitdepth) > in.size()) return 84; + return encode(out, in.empty() ? 0 : &in[0], w, h, colortype, bitdepth); +} + +unsigned encode(std::vector& out, + const unsigned char* in, unsigned w, unsigned h, + State& state) +{ + unsigned char* buffer; + size_t buffersize; + unsigned error = lodepng_encode(&buffer, &buffersize, in, w, h, &state); + if(buffer) { - return encode(out, in.empty() ? 0 : &in[0], w, h, colorType, bitDepth); + out.insert(out.end(), &buffer[0], &buffer[buffersize]); + myfree(buffer); } + return error; +} + +unsigned encode(std::vector& out, + const std::vector& in, unsigned w, unsigned h, + State& state) +{ + if(lodepng_get_raw_size(w, h, &state.info_raw) > in.size()) return 84; + return encode(out, in.empty() ? 0 : &in[0], w, h, state); +} #ifdef LODEPNG_COMPILE_DISK - unsigned encode(const std::string& filename, const unsigned char* in, unsigned w, unsigned h, - unsigned colorType, unsigned bitDepth) - { - std::vector buffer; - Encoder encoder; - encoder.getInfoRaw().color.colorType = colorType; - encoder.getInfoRaw().color.bitDepth = bitDepth; - encoder.encode(buffer, in, w, h); - if(!encoder.hasError()) saveFile(buffer, filename); - return encoder.getError(); - } +unsigned encode(const std::string& filename, + const unsigned char* in, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth) +{ + std::vector buffer; + unsigned error = encode(buffer, in, w, h, colortype, bitdepth); + if(!error) save_file(buffer, filename); + return error; +} - unsigned encode(const std::string& filename, const std::vector& in, unsigned w, unsigned h, - unsigned colorType, unsigned bitDepth) - { - return encode(filename, in.empty() ? 0 : &in[0], w, h, colorType, bitDepth); - } +unsigned encode(const std::string& filename, + const std::vector& in, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth) +{ + if(lodepng_get_raw_size_lct(w, h, colortype, bitdepth) > in.size()) return 84; + return encode(filename, in.empty() ? 0 : &in[0], w, h, colortype, bitdepth); +} #endif //LODEPNG_COMPILE_DISK #endif //LODEPNG_COMPILE_ENCODER #endif //LODEPNG_COMPILE_PNG -} //namespace LodePNG -#endif /*__cplusplus C++ RAII wrapper*/ +} //namespace lodepng +#endif /*LODEPNG_COMPILE_CPP*/ diff --git a/src/lodepng.h b/src/lodepng.h index a0a654f7..6057acc1 100644 --- a/src/lodepng.h +++ b/src/lodepng.h @@ -1,10 +1,7 @@ -#ifndef LODEPNG_H_ -#define LODEPNG_H_ - /* -LodePNG version 20110908 +LodePNG version 20130128 -Copyright (c) 2005-2011 Lode Vandevenne +Copyright (c) 2005-2013 Lode Vandevenne This software is provided 'as-is', without any express or implied warranty. In no event will the authors be held liable for any damages @@ -36,369 +33,340 @@ freely, subject to the following restrictions: #include #endif /*__cplusplus*/ -/* ////////////////////////////////////////////////////////////////////////// */ -/* Code Sections */ -/* ////////////////////////////////////////////////////////////////////////// */ - /* The following #defines are used to create code sections. They can be disabled to disable code sections, which can give faster compile time and smaller binary. +The "NO_COMPILE" defines are designed to be used to pass as defines to the +compiler command to disable them without modifying this header, e.g. +-DLODEPNG_NO_COMPILE_ZLIB for gcc. */ - -/*deflate&zlib encoder and deflate&zlib decoder. -If this is disabled, you need to implement the dummy LodePNG_zlib_compress and -LodePNG_zlib_decompress functions in the #else belonging to this #define in the -source file.*/ +/*deflate & zlib. If disabled, you must specify alternative zlib functions in +the custom_zlib field of the compress and decompress settings*/ +#ifndef LODEPNG_NO_COMPILE_ZLIB #define LODEPNG_COMPILE_ZLIB +#endif /*png encoder and png decoder*/ +#ifndef LODEPNG_NO_COMPILE_PNG #define LODEPNG_COMPILE_PNG +#endif /*deflate&zlib decoder and png decoder*/ +#ifndef LODEPNG_NO_COMPILE_DECODER #define LODEPNG_COMPILE_DECODER +#endif /*deflate&zlib encoder and png encoder*/ +#ifndef LODEPNG_NO_COMPILE_ENCODER #define LODEPNG_COMPILE_ENCODER +#endif /*the optional built in harddisk file loading and saving functions*/ +#ifndef LODEPNG_NO_COMPILE_DISK #define LODEPNG_COMPILE_DISK -/*any code or struct datamember related to chunks other than IHDR, IDAT, PLTE, tRNS, IEND*/ +#endif +/*support for chunks other than IHDR, IDAT, PLTE, tRNS, IEND: ancillary and unknown chunks*/ +#ifndef LODEPNG_NO_COMPILE_ANCILLARY_CHUNKS #define LODEPNG_COMPILE_ANCILLARY_CHUNKS -/*handling of unknown chunks*/ -#define LODEPNG_COMPILE_UNKNOWN_CHUNKS +#endif /*ability to convert error numerical codes to English text string*/ +#ifndef LODEPNG_NO_COMPILE_ERROR_TEXT #define LODEPNG_COMPILE_ERROR_TEXT - -/* ////////////////////////////////////////////////////////////////////////// */ -/* Simple Functions */ -/* ////////////////////////////////////////////////////////////////////////// */ - -/* -This are the simple C and C++ functions, which cover basic usage. -Further on in the header file are the more advanced functions allowing custom behaviour. -*/ +#endif +/*compile the C++ version (you can disable the C++ wrapper here even when compiling for C++)*/ +#ifdef __cplusplus +#ifndef LODEPNG_NO_COMPILE_CPP +#define LODEPNG_COMPILE_CPP +#endif +#endif #ifdef LODEPNG_COMPILE_PNG - -/*constants for the PNG color types. "LCT" = "LodePNG Color Type"*/ -#define LCT_GREY 0 /*PNG color type greyscale*/ -#define LCT_RGB 2 /*PNG color type RGB*/ -#define LCT_PALETTE 3 /*PNG color type palette*/ -#define LCT_GREY_ALPHA 4 /*PNG color type greyscale with alpha*/ -#define LCT_RGBA 6 /*PNG color type RGB with alpha*/ +/*The PNG color types (also used for raw).*/ +typedef enum LodePNGColorType +{ + LCT_GREY = 0, /*greyscale: 1,2,4,8,16 bit*/ + LCT_RGB = 2, /*RGB: 8,16 bit*/ + LCT_PALETTE = 3, /*palette: 1,2,4,8 bit*/ + LCT_GREY_ALPHA = 4, /*greyscale with alpha: 8,16 bit*/ + LCT_RGBA = 6 /*RGB with alpha: 8,16 bit*/ +} LodePNGColorType; #ifdef LODEPNG_COMPILE_DECODER /* Converts PNG data in memory to raw pixel data. out: Output parameter. Pointer to buffer that will contain the raw pixel data. - Its size is w * h * (bytes per pixel), bytes per pixel depends on colorType and bitDepth. + After decoding, its size is w * h * (bytes per pixel) bytes larger than + initially. Bytes per pixel depends on colortype and bitdepth. Must be freed after usage with free(*out). + Note: for 16-bit per channel colors, uses big endian format like PNG does. w: Output parameter. Pointer to width of pixel data. h: Output parameter. Pointer to height of pixel data. in: Memory buffer with the PNG file. insize: size of the in buffer. -colorType: the desired color type for the raw output image. See explanation on PNG color types. -bitDepth: the desired bit depth for the raw output image. See explanation on PNG color types. +colortype: the desired color type for the raw output image. See explanation on PNG color types. +bitdepth: the desired bit depth for the raw output image. See explanation on PNG color types. Return value: LodePNG error code (0 means no error). */ -unsigned LodePNG_decode(unsigned char** out, unsigned* w, unsigned* h, - const unsigned char* in, size_t insize, unsigned colorType, unsigned bitDepth); +unsigned lodepng_decode_memory(unsigned char** out, unsigned* w, unsigned* h, + const unsigned char* in, size_t insize, + LodePNGColorType colortype, unsigned bitdepth); -/*Same as LodePNG_decode, but uses colorType = 6 and bitDepth = 8 by default (32-bit RGBA)*/ -unsigned LodePNG_decode32(unsigned char** out, unsigned* w, unsigned* h, +/*Same as lodepng_decode_memory, but always decodes to 32-bit RGBA raw image*/ +unsigned lodepng_decode32(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, size_t insize); -/*Same as LodePNG_decode, but uses colorType = 2 and bitDepth = 8 by default (24-bit RGB)*/ -unsigned LodePNG_decode24(unsigned char** out, unsigned* w, unsigned* h, +/*Same as lodepng_decode_memory, but always decodes to 24-bit RGB raw image*/ +unsigned lodepng_decode24(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, size_t insize); #ifdef LODEPNG_COMPILE_DISK /* Load PNG from disk, from file with given name. -out: Output parameter. Pointer to buffer that will contain the raw pixel data. - Its size is w * h * (bytes per pixel), bytes per pixel depends on colorType and bitDepth. - Must be freed after usage with free(*out). -w: Output parameter. Pointer to width of pixel data. -h: Output parameter. Pointer to height of pixel data. -filename: Path on disk of the PNG file. -colorType: the desired color type for the raw output image. See explanation on PNG color types. -bitDepth: the desired bit depth for the raw output image. See explanation on PNG color types. -Return value: LodePNG error code (0 means no error). +Same as the other decode functions, but instead takes a filename as input. */ -unsigned LodePNG_decode_file(unsigned char** out, unsigned* w, unsigned* h, - const char* filename, unsigned colorType, unsigned bitDepth); - -/*Same as LodePNG_decode_file, but uses colorType = 6 and bitDepth = 8 by default (32-bit RGBA)*/ -unsigned LodePNG_decode32_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename); - -/*Same as LodePNG_decode_file, but uses colorType = 2 and bitDepth = 8 by default (24-bit RGB)*/ -unsigned LodePNG_decode24_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename); +unsigned lodepng_decode_file(unsigned char** out, unsigned* w, unsigned* h, + const char* filename, + LodePNGColorType colortype, unsigned bitdepth); +/*Same as lodepng_decode_file, but always decodes to 32-bit RGBA raw image.*/ +unsigned lodepng_decode32_file(unsigned char** out, unsigned* w, unsigned* h, + const char* filename); +/*Same as lodepng_decode_file, but always decodes to 24-bit RGB raw image.*/ +unsigned lodepng_decode24_file(unsigned char** out, unsigned* w, unsigned* h, + const char* filename); #endif /*LODEPNG_COMPILE_DISK*/ #endif /*LODEPNG_COMPILE_DECODER*/ + #ifdef LODEPNG_COMPILE_ENCODER /* -Converts raw pixel data into a PNG image in memory. The colorType and bitDepth +Converts raw pixel data into a PNG image in memory. The colortype and bitdepth of the output PNG image cannot be chosen, they are automatically determined - by the colorType, bitDepth and content of the input pixel data. -out: Output parameter. Pointer to buffer that will contain the raw pixel data. + by the colortype, bitdepth and content of the input pixel data. + Note: for 16-bit per channel colors, needs big endian format like PNG does. +out: Output parameter. Pointer to buffer that will contain the PNG image data. Must be freed after usage with free(*out). outsize: Output parameter. Pointer to the size in bytes of the out buffer. image: The raw pixel data to encode. The size of this buffer should be - w * h * (bytes per pixel), bytes per pixel depends on colorType and bitDepth. + w * h * (bytes per pixel), bytes per pixel depends on colortype and bitdepth. w: width of the raw pixel data in pixels. h: height of the raw pixel data in pixels. -colorType: the color type of the raw input image. See explanation on PNG color types. -bitDepth: the bit depth of the raw input image. See explanation on PNG color types. +colortype: the color type of the raw input image. See explanation on PNG color types. +bitdepth: the bit depth of the raw input image. See explanation on PNG color types. Return value: LodePNG error code (0 means no error). */ -unsigned LodePNG_encode(unsigned char** out, size_t* outsize, - const unsigned char* image, unsigned w, unsigned h, unsigned colorType, unsigned bitDepth); +unsigned lodepng_encode_memory(unsigned char** out, size_t* outsize, + const unsigned char* image, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth); -/*Same as LodePNG_encode, but uses colorType = 6 and bitDepth = 8 by default (32-bit RGBA).*/ -unsigned LodePNG_encode32(unsigned char** out, size_t* outsize, const unsigned char* image, unsigned w, unsigned h); +/*Same as lodepng_encode_memory, but always encodes from 32-bit RGBA raw image.*/ +unsigned lodepng_encode32(unsigned char** out, size_t* outsize, + const unsigned char* image, unsigned w, unsigned h); -/*Same as LodePNG_encode, but uses colorType = 2 and bitDepth = 8 by default (24-bit RGB).*/ -unsigned LodePNG_encode24(unsigned char** out, size_t* outsize, const unsigned char* image, unsigned w, unsigned h); +/*Same as lodepng_encode_memory, but always encodes from 24-bit RGB raw image.*/ +unsigned lodepng_encode24(unsigned char** out, size_t* outsize, + const unsigned char* image, unsigned w, unsigned h); #ifdef LODEPNG_COMPILE_DISK - /* -Converts raw pixel data into a PNG file on disk. Same as LodePNG_encode, but -outputs to disk instead of memory buffer. -filename: path to file on disk to write the PNG image to. -image: The raw pixel data to encode. The size of this buffer should be - w * h * (bytes per pixel), bytes per pixel depends on colorType and bitDepth. -w: width of the raw pixel data in pixels. -h: height of the raw pixel data in pixels. -colorType: the color type of the raw input image. See explanation on PNG color types. -bitDepth: the bit depth of the raw input image. See explanation on PNG color types. -Return value: LodePNG error code (0 means no error). +Converts raw pixel data into a PNG file on disk. +Same as the other encode functions, but instead takes a filename as output. +NOTE: This overwrites existing files without warning! */ -unsigned LodePNG_encode_file(const char* filename, const unsigned char* image, - unsigned w, unsigned h, unsigned colorType, unsigned bitDepth); +unsigned lodepng_encode_file(const char* filename, + const unsigned char* image, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth); -/*Same as LodePNG_encode_file, but uses colorType = 6 and bitDepth = 8 by default (32-bit RGBS).*/ -unsigned LodePNG_encode32_file(const char* filename, const unsigned char* image, unsigned w, unsigned h); +/*Same as lodepng_encode_file, but always encodes from 32-bit RGBA raw image.*/ +unsigned lodepng_encode32_file(const char* filename, + const unsigned char* image, unsigned w, unsigned h); -/*Same as LodePNG_encode_file, but uses colorType = 2 and bitDepth = 8 by default (24-bit RGB).*/ -unsigned LodePNG_encode24_file(const char* filename, const unsigned char* image, unsigned w, unsigned h); +/*Same as lodepng_encode_file, but always encodes from 24-bit RGB raw image.*/ +unsigned lodepng_encode24_file(const char* filename, + const unsigned char* image, unsigned w, unsigned h); #endif /*LODEPNG_COMPILE_DISK*/ #endif /*LODEPNG_COMPILE_ENCODER*/ -#ifdef __cplusplus -namespace LodePNG + +#ifdef LODEPNG_COMPILE_CPP +namespace lodepng { - #ifdef LODEPNG_COMPILE_DECODER - /* - Converts PNG data in memory to raw pixel data. - out: Output parameter, std::vector containing the raw pixel data. Its size - will be w * h * (bytes per pixel), where bytes per pixel is 4 if the default - colorType=6 and bitDepth=8 is used. The pixels are 32-bit RGBA bit in that case. - w: Output parameter, width of the image in pixels. - h: Output parameter, height of the image in pixels. - in: Memory buffer with the PNG file. - insize: size of the in buffer. - colorType: the desired color type for the raw output image. See explanation on PNG color types. - bitDepth: the desired bit depth for the raw output image. See explanation on PNG color types. - Return value: LodePNG error code (0 means no error). - */ - unsigned decode(std::vector& out, unsigned& w, unsigned& h, - const unsigned char* in, size_t insize, unsigned colorType = LCT_RGBA, unsigned bitDepth = 8); - - /* - Same as the decode function that takes a unsigned char buffer, but instead of giving - a pointer and a size, this takes the input buffer as an std::vector. - */ - unsigned decode(std::vector& out, unsigned& w, unsigned& h, - const std::vector& in, unsigned colorType = LCT_RGBA, unsigned bitDepth = 8); +/*Same as lodepng_decode_memory, but decodes to an std::vector.*/ +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + const unsigned char* in, size_t insize, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + const std::vector& in, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); #ifdef LODEPNG_COMPILE_DISK - /* - Converts PNG file from disk to raw pixel data in memory. - out: Output parameter, std::vector containing the raw pixel data. Its size - will be w * h * (bytes per pixel), where bytes per pixel is 4 if the default - colorType=6 and bitDepth=8 is used. The pixels are 32-bit RGBA bit in that case. - w: Output parameter, width of the image in pixels. - h: Output parameter, height of the image in pixels. - filename: Path to PNG file on disk. - colorType: the desired color type for the raw output image. See explanation on PNG color types. - bitDepth: the desired bit depth for the raw output image. See explanation on PNG color types. - Return value: LodePNG error code (0 means no error). - */ - unsigned decode(std::vector& out, unsigned& w, unsigned& h, - const std::string& filename, unsigned colorType = LCT_RGBA, unsigned bitDepth = 8); +/* +Converts PNG file from disk to raw pixel data in memory. +Same as the other decode functions, but instead takes a filename as input. +*/ +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + const std::string& filename, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); #endif //LODEPNG_COMPILE_DISK #endif //LODEPNG_COMPILE_DECODER #ifdef LODEPNG_COMPILE_ENCODER - /* - Converts 32-bit RGBA raw pixel data into a PNG image in memory. - out: Output parameter, std::vector containing the PNG image data. - in: Memory buffer with raw pixel data. The size of this buffer should be - w * h * (bytes per pixel), With the default colorType=6 and bitDepth=8, bytes - per pixel should be 4 and the data is a 32-bit RGBA pixel buffer. - w: Width of the image in pixels. - h: Height of the image in pixels. - colorType: the color type of the raw input image. See explanation on PNG color types. - bitDepth: the bit depth of the raw input image. See explanation on PNG color types. - Return value: LodePNG error code (0 means no error). - */ - unsigned encode(std::vector& out, const unsigned char* in, - unsigned w, unsigned h, unsigned colorType = LCT_RGBA, unsigned bitDepth = 8); - - /* - Same as the encode function that takes a unsigned char buffer, but instead of giving - a pointer and a size, this takes the input buffer as an std::vector. - */ - unsigned encode(std::vector& out, const std::vector& in, - unsigned w, unsigned h, unsigned colorType = LCT_RGBA, unsigned bitDepth = 8); +/*Same as lodepng_encode_memory, but encodes to an std::vector.*/ +unsigned encode(std::vector& out, + const unsigned char* in, unsigned w, unsigned h, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +unsigned encode(std::vector& out, + const std::vector& in, unsigned w, unsigned h, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); #ifdef LODEPNG_COMPILE_DISK - /* - Converts 32-bit RGBA raw pixel data into a PNG file on disk. - filename: Path to the file to write the PNG image to. - in: Memory buffer with raw pixel data. The size of this buffer should be - w * h * (bytes per pixel), With the default colorType=6 and bitDepth=8, bytes - per pixel should be 4 and the data is a 32-bit RGBA pixel buffer. - w: Width of the image in pixels. - h: Height of the image in pixels. - colorType: the color type of the raw input image. See explanation on PNG color types. - bitDepth: the bit depth of the raw input image. See explanation on PNG color types. - Return value: LodePNG error code (0 means no error). - */ - unsigned encode(const std::string& filename, const unsigned char* in, - unsigned w, unsigned h, unsigned colorType = LCT_RGBA, unsigned bitDepth = 8); - - /* - Same as the encode function that takes a unsigned char buffer, but instead of giving - a pointer and a size, this takes the input buffer as an std::vector. - */ - unsigned encode(const std::string& filename, const std::vector& in, - unsigned w, unsigned h, unsigned colorType = LCT_RGBA, unsigned bitDepth = 8); +/* +Converts 32-bit RGBA raw pixel data into a PNG file on disk. +Same as the other encode functions, but instead takes a filename as output. +NOTE: This overwrites existing files without warning! +*/ +unsigned encode(const std::string& filename, + const unsigned char* in, unsigned w, unsigned h, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +unsigned encode(const std::string& filename, + const std::vector& in, unsigned w, unsigned h, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); #endif //LODEPNG_COMPILE_DISK #endif //LODEPNG_COMPILE_ENCODER -} //namespace LodePNG -#endif /*__cplusplus*/ +} //namespace lodepng +#endif /*LODEPNG_COMPILE_CPP*/ #endif /*LODEPNG_COMPILE_PNG*/ #ifdef LODEPNG_COMPILE_ERROR_TEXT -/* -Returns a textual description of the error code, in English. The -numerical value of the code itself is not included in this description. -*/ -const char* LodePNG_error_text(unsigned code); +/*Returns an English description of the numerical error code.*/ +const char* lodepng_error_text(unsigned code); #endif /*LODEPNG_COMPILE_ERROR_TEXT*/ -/* ////////////////////////////////////////////////////////////////////////// */ -/* Inflate & Deflate Setting Structs */ -/* ////////////////////////////////////////////////////////////////////////// */ - -/* -These structs contain settings for the decompression and compression of the -PNG files. Typically you won't need these directly. -*/ - #ifdef LODEPNG_COMPILE_DECODER -typedef struct LodePNG_DecompressSettings +/*Settings for zlib decompression*/ +typedef struct LodePNGDecompressSettings LodePNGDecompressSettings; +struct LodePNGDecompressSettings { - unsigned ignoreAdler32; /*if 1, continue and don't give an error message if the Adler32 checksum is corrupted*/ -} LodePNG_DecompressSettings; + unsigned ignore_adler32; /*if 1, continue and don't give an error message if the Adler32 checksum is corrupted*/ -extern const LodePNG_DecompressSettings LodePNG_defaultDecompressSettings; -void LodePNG_DecompressSettings_init(LodePNG_DecompressSettings* settings); + /*use custom zlib decoder instead of built in one (default: null)*/ + unsigned (*custom_zlib)(unsigned char**, size_t*, + const unsigned char*, size_t, + const LodePNGDecompressSettings*); + /*use custom deflate decoder instead of built in one (default: null) + if custom_zlib is used, custom_deflate is ignored since only the built in + zlib function will call custom_deflate*/ + unsigned (*custom_inflate)(unsigned char**, size_t*, + const unsigned char*, size_t, + const LodePNGDecompressSettings*); + + void* custom_context; /*optional custom settings for custom functions*/ +}; + +extern const LodePNGDecompressSettings lodepng_default_decompress_settings; +void lodepng_decompress_settings_init(LodePNGDecompressSettings* settings); #endif /*LODEPNG_COMPILE_DECODER*/ #ifdef LODEPNG_COMPILE_ENCODER /* -Compression settings. Tweaking these settings tweaks the balance between -speed and compression ratio. +Settings for zlib compression. Tweaking these settings tweaks the balance +between speed and compression ratio. */ -typedef struct LodePNG_CompressSettings /*deflate = compress*/ +typedef struct LodePNGCompressSettings LodePNGCompressSettings; +struct LodePNGCompressSettings /*deflate = compress*/ { /*LZ77 related settings*/ unsigned btype; /*the block type for LZ (0, 1, 2 or 3, see zlib standard). Should be 2 for proper compression.*/ - unsigned useLZ77; /*whether or not to use LZ77. Should be 1 for proper compression.*/ - unsigned windowSize; /*the maximum is 32768, higher gives more compression but is slower. Typical value: 2048.*/ -} LodePNG_CompressSettings; + unsigned use_lz77; /*whether or not to use LZ77. Should be 1 for proper compression.*/ + unsigned windowsize; /*the maximum is 32768, higher gives more compression but is slower. Typical value: 2048.*/ + unsigned minmatch; /*mininum lz77 length. 3 is normally best, 6 can be better for some PNGs. Default: 0*/ + unsigned nicematch; /*stop searching if >= this length found. Set to 258 for best compression. Default: 128*/ + unsigned lazymatching; /*use lazy matching: better compression but a bit slower. Default: true*/ -extern const LodePNG_CompressSettings LodePNG_defaultCompressSettings; -void LodePNG_CompressSettings_init(LodePNG_CompressSettings* settings); + /*use custom zlib encoder instead of built in one (default: null)*/ + unsigned (*custom_zlib)(unsigned char**, size_t*, + const unsigned char*, size_t, + const LodePNGCompressSettings*); + /*use custom deflate encoder instead of built in one (default: null) + if custom_zlib is used, custom_deflate is ignored since only the built in + zlib function will call custom_deflate*/ + unsigned (*custom_deflate)(unsigned char**, size_t*, + const unsigned char*, size_t, + const LodePNGCompressSettings*); + + void* custom_context; /*optional custom settings for custom functions*/ +}; + +extern const LodePNGCompressSettings lodepng_default_compress_settings; +void lodepng_compress_settings_init(LodePNGCompressSettings* settings); #endif /*LODEPNG_COMPILE_ENCODER*/ #ifdef LODEPNG_COMPILE_PNG -/* ////////////////////////////////////////////////////////////////////////// */ -/* PNG and Raw Image Information Structs */ -/* ////////////////////////////////////////////////////////////////////////// */ - /* -Info about the color type of an image. -The same LodePNG_InfoColor struct is used for both the PNG and raw image type, -even though they are two totally different things. +Color mode of an image. Contains all information required to decode the pixel +bits to RGBA colors. This information is the same as used in the PNG file +format, and is used both for PNG and raw image data in LodePNG. */ -typedef struct LodePNG_InfoColor +typedef struct LodePNGColorMode { /*header (IHDR)*/ - unsigned colorType; /*color type, see PNG standard or documentation further in this header file*/ - unsigned bitDepth; /*bits per sample, see PNG standard or documentation further in this header file*/ + LodePNGColorType colortype; /*color type, see PNG standard or documentation further in this header file*/ + unsigned bitdepth; /*bits per sample, see PNG standard or documentation further in this header file*/ /* palette (PLTE and tRNS) - This is a dynamically allocated unsigned char array with the colors of the palette, including alpha. - The value palettesize indicates the amount of colors in the palette. - The allocated size of the buffer is 4 * palettesize bytes, in order RGBARGBARGBA... - - When encoding a PNG, to store your colors in the palette of the LodePNG_InfoRaw, first use - LodePNG_InfoColor_clearPalette, then for each color use LodePNG_InfoColor_addPalette. - + Dynamically allocated with the colors of the palette, including alpha. + When encoding a PNG, to store your colors in the palette of the LodePNGColorMode, first use + lodepng_palette_clear, then for each color use lodepng_palette_add. If you encode an image without alpha with palette, don't forget to put value 255 in each A byte of the palette. When decoding, by default you can ignore this palette, since LodePNG already fills the palette colors in the pixels of the raw RGBA output. + + The palette is only supported for color type 3. */ unsigned char* palette; /*palette in RGBARGBA... order*/ size_t palettesize; /*palette size in number of colors (amount of bytes is 4 * palettesize)*/ /* transparent color key (tRNS) - This color uses the same bit depth as the bitDepth value in this struct, which can be 1-bit to 16-bit. + + This color uses the same bit depth as the bitdepth value in this struct, which can be 1-bit to 16-bit. For greyscale PNGs, r, g and b will all 3 be set to the same. When decoding, by default you can ignore this information, since LodePNG sets pixels with this key to transparent already in the raw RGBA output. + + The color key is only supported for color types 0 and 2. */ unsigned key_defined; /*is a transparent color key given? 0 = false, 1 = true*/ unsigned key_r; /*red/greyscale component of color key*/ unsigned key_g; /*green component of color key*/ unsigned key_b; /*blue component of color key*/ -} LodePNG_InfoColor; +} LodePNGColorMode; /*init, cleanup and copy functions to use with this struct*/ -void LodePNG_InfoColor_init(LodePNG_InfoColor* info); -void LodePNG_InfoColor_cleanup(LodePNG_InfoColor* info); +void lodepng_color_mode_init(LodePNGColorMode* info); +void lodepng_color_mode_cleanup(LodePNGColorMode* info); /*return value is error code (0 means no error)*/ -unsigned LodePNG_InfoColor_copy(LodePNG_InfoColor* dest, const LodePNG_InfoColor* source); +unsigned lodepng_color_mode_copy(LodePNGColorMode* dest, const LodePNGColorMode* source); -void LodePNG_InfoColor_clearPalette(LodePNG_InfoColor* info); +void lodepng_palette_clear(LodePNGColorMode* info); /*add 1 color to the palette*/ -unsigned LodePNG_InfoColor_addPalette(LodePNG_InfoColor* info, unsigned char r, - unsigned char g, unsigned char b, unsigned char a); +unsigned lodepng_palette_add(LodePNGColorMode* info, + unsigned char r, unsigned char g, unsigned char b, unsigned char a); -/*additional color info*/ - -/*get the total amount of bits per pixel, based on colorType and bitDepth in the struct*/ -unsigned LodePNG_InfoColor_getBpp(const LodePNG_InfoColor* info); -/*get the amount of color channels used, based on colorType in the struct. +/*get the total amount of bits per pixel, based on colortype and bitdepth in the struct*/ +unsigned lodepng_get_bpp(const LodePNGColorMode* info); +/*get the amount of color channels used, based on colortype in the struct. If a palette is used, it counts as 1 channel.*/ -unsigned LodePNG_InfoColor_getChannels(const LodePNG_InfoColor* info); -/*is it a greyscale type? (only colorType 0 or 4)*/ -unsigned LodePNG_InfoColor_isGreyscaleType(const LodePNG_InfoColor* info); -/*has it got an alpha channel? (only colorType 2 or 6)*/ -unsigned LodePNG_InfoColor_isAlphaType(const LodePNG_InfoColor* info); -/*has it got a palette? (only colorType 3)*/ -unsigned LodePNG_InfoColor_isPaletteType(const LodePNG_InfoColor* info); +unsigned lodepng_get_channels(const LodePNGColorMode* info); +/*is it a greyscale type? (only colortype 0 or 4)*/ +unsigned lodepng_is_greyscale_type(const LodePNGColorMode* info); +/*has it got an alpha channel? (only colortype 2 or 6)*/ +unsigned lodepng_is_alpha_type(const LodePNGColorMode* info); +/*has it got a palette? (only colortype 3)*/ +unsigned lodepng_is_palette_type(const LodePNGColorMode* info); /*only returns true if there is a palette and there is a value in the palette with alpha < 255. Loops through the palette to check this.*/ -unsigned LodePNG_InfoColor_hasPaletteAlpha(const LodePNG_InfoColor* info); - +unsigned lodepng_has_palette_alpha(const LodePNGColorMode* info); /* Check if the given color info indicates the possibility of having non-opaque pixels in the PNG image. Returns true if the image can have translucent or invisible pixels (it still be opaque if it doesn't use such pixels). @@ -406,144 +374,36 @@ Returns false if the image can only have opaque pixels. In detail, it returns true only if it's a color type with alpha, or has a palette with non-opaque values, or if "key_defined" is true. */ -unsigned LodePNG_InfoColor_canHaveAlpha(const LodePNG_InfoColor* info); +unsigned lodepng_can_have_alpha(const LodePNGColorMode* info); +/*Returns the byte size of a raw image buffer with given width, height and color mode*/ +size_t lodepng_get_raw_size(unsigned w, unsigned h, const LodePNGColorMode* color); #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS -/* -The information of a Time chunk in PNG. -To make the encoder add a time chunk, set time_defined to 1 and fill in -the correct values in all the time parameters. LodePNG will not fill the current -time in these values itself, all it does is copy them over into the chunk bytes. -*/ -typedef struct LodePNG_Time +/*The information of a Time chunk in PNG.*/ +typedef struct LodePNGTime { - unsigned year; /*2 bytes used (0-65535)*/ - unsigned char month; /*1-12*/ - unsigned char day; /*1-31*/ - unsigned char hour; /*0-23*/ - unsigned char minute; /*0-59*/ - unsigned char second; /*0-60 (to allow for leap seconds)*/ -} LodePNG_Time; - -/* -Info about text chunks in a PNG file. The arrays can contain multiple keys -and strings. The amount of keys and strings is the same. The amount of strings -ends when the pointer to the string is a null pointer. - -They keyword of text chunks gives a short description what the actual text -represents. There are a few standard standard keywords recognised -by many programs: Title, Author, Description, Copyright, Creation Time, -Software, Disclaimer, Warning, Source, Comment. It's allowed to use other keys. - -A keyword is minimum 1 character and maximum 79 characters long. It's -discouraged to use a single line length longer than 79 characters for texts. -*/ -typedef struct LodePNG_Text /*non-international text*/ -{ - /*Don't allocate these text buffers yourself. Use the init/cleanup functions - correctly and use LodePNG_Text_add and LodePNG_Text_clear.*/ - size_t num; /*the amount of texts in these char** buffers (there may be more texts in itext)*/ - char** keys; /*the keyword of a text chunk (e.g. "Comment")*/ - char** strings; /*the actual text*/ -} LodePNG_Text; - -/*init, cleanup and copy functions to use with this struct*/ -void LodePNG_Text_init(LodePNG_Text* text); -void LodePNG_Text_cleanup(LodePNG_Text* text); -/*return value is error code (0 means no error)*/ -unsigned LodePNG_Text_copy(LodePNG_Text* dest, const LodePNG_Text* source); - -/*Use these functions instead of allocating the char**s manually*/ -void LodePNG_Text_clear(LodePNG_Text* text); /*use this to clear the texts again after you filled them in*/ -unsigned LodePNG_Text_add(LodePNG_Text* text, const char* key, const char* str); /*push back both texts at once*/ - -/* -Info about international text chunks in a PNG file. The arrays can contain multiple keys -and strings. The amount of keys, lengtags, transkeys and strings is the same. -The amount of strings ends when the pointer to the string is a null pointer. - -A keyword is minimum 1 character and maximum 79 characters long. It's -discouraged to use a single line length longer than 79 characters for texts. -*/ -typedef struct LodePNG_IText /*international text*/ -{ - /*Don't allocate these text buffers yourself. Use the init/cleanup functions - correctly and use LodePNG_IText_add and LodePNG_IText_clear.*/ - - /*the amount of international texts in this PNG*/ - size_t num; - /*the English keyword of the text chunk (e.g. "Comment")*/ - char** keys; - /*the language tag for this text's international language, ISO/IEC 646 string, e.g. ISO 639 language tag*/ - char** langtags; - /*keyword translated to the international language - UTF-8 string*/ - char** transkeys; - /*the actual international text - UTF-8 string*/ - char** strings; -} LodePNG_IText; - -/*init, cleanup and copy functions to use with this struct*/ -void LodePNG_IText_init(LodePNG_IText* text); -void LodePNG_IText_cleanup(LodePNG_IText* text); -/*return value is error code (0 means no error)*/ -unsigned LodePNG_IText_copy(LodePNG_IText* dest, const LodePNG_IText* source); - -/*Use these functions instead of allocating the char**s manually*/ -void LodePNG_IText_clear(LodePNG_IText* text); /*use this to clear the itexts again after you filled them in*/ -unsigned LodePNG_IText_add(LodePNG_IText* text, const char* key, const char* langtag, - const char* transkey, const char* str); /*push back the 4 texts of 1 chunk at once*/ + unsigned year; /*2 bytes used (0-65535)*/ + unsigned month; /*1-12*/ + unsigned day; /*1-31*/ + unsigned hour; /*0-23*/ + unsigned minute; /*0-59*/ + unsigned second; /*0-60 (to allow for leap seconds)*/ +} LodePNGTime; #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS -/* -Unknown chunks read from the PNG, or extra chunks the user wants to have added -in the encoded PNG. -*/ -typedef struct LodePNG_UnknownChunks +/*Information about the PNG image, except pixels, width and height.*/ +typedef struct LodePNGInfo { - /*There are 3 buffers, one for each position in the PNG where unknown chunks can appear - each buffer contains all unknown chunks for that position consecutively - The 3 buffers are the unknown chunks between certain critical chunks: - 0: IHDR-PLTE, 1: PLTE-IDAT, 2: IDAT-IEND - - Do not allocate or traverse this data yourself. Use the chunk traversing functions declared - later, such as LodePNG_chunk_next and LodePNG_append_chunk, to read/write this struct. - */ - unsigned char* data[3]; - size_t datasize[3]; /*size in bytes of the unknown chunks, given for protection*/ - -} LodePNG_UnknownChunks; - -/*init, cleanup and copy functions to use with this struct*/ -void LodePNG_UnknownChunks_init(LodePNG_UnknownChunks* chunks); -void LodePNG_UnknownChunks_cleanup(LodePNG_UnknownChunks* chunks); -/*return value is error code (0 means no error)*/ -unsigned LodePNG_UnknownChunks_copy(LodePNG_UnknownChunks* dest, const LodePNG_UnknownChunks* src); -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ - -/* -Information about the PNG image, except pixels and sometimes except width and height. -*/ -typedef struct LodePNG_InfoPng -{ - /*header (IHDR), palette (PLTE) and transparency (tRNS)*/ - - /* - Note: width and height are only used as information of a decoded PNG image. When encoding one, you don't have - to specify width and height in an LodePNG_Info struct, but you give them as parameters of the encode function. - The rest of the LodePNG_Info struct IS used by the encoder though! - */ - unsigned width; /*width of the image in pixels (ignored by encoder, but filled in by decoder)*/ - unsigned height; /*height of the image in pixels (ignored by encoder, but filled in by decoder)*/ - unsigned compressionMethod; /*compression method of the original file. Always 0.*/ - unsigned filterMethod; /*filter method of the original file*/ - unsigned interlaceMethod; /*interlace method of the original file*/ - LodePNG_InfoColor color; /*color type and bits, palette and transparency of the PNG file*/ + /*header (IHDR), palette (PLTE) and transparency (tRNS) chunks*/ + unsigned compression_method;/*compression method of the original file. Always 0.*/ + unsigned filter_method; /*filter method of the original file*/ + unsigned interlace_method; /*interlace method of the original file*/ + LodePNGColorMode color; /*color type and bits, palette and transparency of the PNG file*/ #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS /* - suggested background color (bKGD) - This color uses the same bit depth as the bitDepth value in this struct, which can be 1-bit to 16-bit. + suggested background color chunk (bKGD) + This color uses the same color mode as the PNG (except alpha channel), which can be 1-bit to 16-bit. For greyscale PNGs, r, g and b will all 3 be set to the same. When encoding the encoder writes the red one. For palette PNGs: When decoding, the RGB value @@ -557,250 +417,290 @@ typedef struct LodePNG_InfoPng unsigned background_g; /*green component of suggested background color*/ unsigned background_b; /*blue component of suggested background color*/ - /*non-international text chunks (tEXt and zTXt)*/ - LodePNG_Text text; + /* + non-international text chunks (tEXt and zTXt) - /*international text chunks (iTXt)*/ - LodePNG_IText itext; + The char** arrays each contain num strings. The actual messages are in + text_strings, while text_keys are keywords that give a short description what + the actual text represents, e.g. Title, Author, Description, or anything else. + + A keyword is minimum 1 character and maximum 79 characters long. It's + discouraged to use a single line length longer than 79 characters for texts. + + Don't allocate these text buffers yourself. Use the init/cleanup functions + correctly and use lodepng_add_text and lodepng_clear_text. + */ + size_t text_num; /*the amount of texts in these char** buffers (there may be more texts in itext)*/ + char** text_keys; /*the keyword of a text chunk (e.g. "Comment")*/ + char** text_strings; /*the actual text*/ + + /* + international text chunks (iTXt) + Similar to the non-international text chunks, but with additional strings + "langtags" and "transkeys". + */ + size_t itext_num; /*the amount of international texts in this PNG*/ + char** itext_keys; /*the English keyword of the text chunk (e.g. "Comment")*/ + char** itext_langtags; /*language tag for this text's language, ISO/IEC 646 string, e.g. ISO 639 language tag*/ + char** itext_transkeys; /*keyword translated to the international language - UTF-8 string*/ + char** itext_strings; /*the actual international text - UTF-8 string*/ /*time chunk (tIME)*/ - unsigned char time_defined; /*if 0, no tIME chunk was or will be generated in the PNG image*/ - LodePNG_Time time; + unsigned time_defined; /*set to 1 to make the encoder generate a tIME chunk*/ + LodePNGTime time; /*phys chunk (pHYs)*/ unsigned phys_defined; /*if 0, there is no pHYs chunk and the values below are undefined, if 1 else there is one*/ unsigned phys_x; /*pixels per unit in x direction*/ unsigned phys_y; /*pixels per unit in y direction*/ - unsigned char phys_unit; /*may be 0 (unknown unit) or 1 (metre)*/ + unsigned phys_unit; /*may be 0 (unknown unit) or 1 (metre)*/ + + /* + unknown chunks + There are 3 buffers, one for each position in the PNG where unknown chunks can appear + each buffer contains all unknown chunks for that position consecutively + The 3 buffers are the unknown chunks between certain critical chunks: + 0: IHDR-PLTE, 1: PLTE-IDAT, 2: IDAT-IEND + Do not allocate or traverse this data yourself. Use the chunk traversing functions declared + later, such as lodepng_chunk_next and lodepng_chunk_append, to read/write this struct. + */ + unsigned char* unknown_chunks_data[3]; + size_t unknown_chunks_size[3]; /*size in bytes of the unknown chunks, given for protection*/ #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS - /*unknown chunks*/ - LodePNG_UnknownChunks unknown_chunks; -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ -} LodePNG_InfoPng; +} LodePNGInfo; /*init, cleanup and copy functions to use with this struct*/ -void LodePNG_InfoPng_init(LodePNG_InfoPng* info); -void LodePNG_InfoPng_cleanup(LodePNG_InfoPng* info); +void lodepng_info_init(LodePNGInfo* info); +void lodepng_info_cleanup(LodePNGInfo* info); /*return value is error code (0 means no error)*/ -unsigned LodePNG_InfoPng_copy(LodePNG_InfoPng* dest, const LodePNG_InfoPng* source); +unsigned lodepng_info_copy(LodePNGInfo* dest, const LodePNGInfo* source); -/* -Contains user-chosen information about the raw image data, which is independent of the PNG image -With raw images, I mean the image data in the form of the simple raw buffer to which the -compressed PNG data is decoded, or from which a PNG image can be encoded. -*/ -typedef struct LodePNG_InfoRaw -{ - LodePNG_InfoColor color; /*color info of the raw image, note that the same struct as for PNG data is used.*/ -} LodePNG_InfoRaw; +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS +void lodepng_clear_text(LodePNGInfo* info); /*use this to clear the texts again after you filled them in*/ +unsigned lodepng_add_text(LodePNGInfo* info, const char* key, const char* str); /*push back both texts at once*/ -/*init, cleanup and copy functions to use with this struct*/ -void LodePNG_InfoRaw_init(LodePNG_InfoRaw* info); -void LodePNG_InfoRaw_cleanup(LodePNG_InfoRaw* info); -/*return value is error code (0 means no error)*/ -unsigned LodePNG_InfoRaw_copy(LodePNG_InfoRaw* dest, const LodePNG_InfoRaw* source); +void lodepng_clear_itext(LodePNGInfo* info); /*use this to clear the itexts again after you filled them in*/ +unsigned lodepng_add_itext(LodePNGInfo* info, const char* key, const char* langtag, + const char* transkey, const char* str); /*push back the 4 texts of 1 chunk at once*/ +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ /* Converts raw buffer from one color type to another color type, based on -LodePNG_InfoColor structs to describe the input and output color type. +LodePNGColorMode structs to describe the input and output color type. See the reference manual at the end of this header file to see which color conversions are supported. return value = LodePNG error code (0 if all went ok, an error if the conversion isn't supported) The out buffer must have size (w * h * bpp + 7) / 8, where bpp is the bits per pixel -of the output color type (LodePNG_InfoColor_getBpp) +of the output color type (lodepng_get_bpp) +Note: for 16-bit per channel colors, uses big endian format like PNG does. */ -unsigned LodePNG_convert(unsigned char* out, const unsigned char* in, LodePNG_InfoColor* infoOut, - LodePNG_InfoColor* infoIn, unsigned w, unsigned h); +unsigned lodepng_convert(unsigned char* out, const unsigned char* in, + LodePNGColorMode* mode_out, LodePNGColorMode* mode_in, + unsigned w, unsigned h); + #ifdef LODEPNG_COMPILE_DECODER - -/* ////////////////////////////////////////////////////////////////////////// */ -/* LodePNG Decoder */ -/* ////////////////////////////////////////////////////////////////////////// */ - /* Settings for the decoder. This contains settings for the PNG and the Zlib decoder, but not the Info settings from the Info structs. */ -typedef struct LodePNG_DecodeSettings +typedef struct LodePNGDecoderSettings { - LodePNG_DecompressSettings zlibsettings; /*in here is the setting to ignore Adler32 checksums*/ + LodePNGDecompressSettings zlibsettings; /*in here is the setting to ignore Adler32 checksums*/ - unsigned ignoreCrc; /*ignore CRC checksums*/ + unsigned ignore_crc; /*ignore CRC checksums*/ unsigned color_convert; /*whether to convert the PNG to the color type you want. Default: yes*/ #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - unsigned readTextChunks; /*if false but rememberUnknownChunks is true, they're stored in the unknown chunks*/ + unsigned read_text_chunks; /*if false but remember_unknown_chunks is true, they're stored in the unknown chunks*/ + /*store all bytes from unknown chunks in the LodePNGInfo (off by default, useful for a png editor)*/ + unsigned remember_unknown_chunks; #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ +} LodePNGDecoderSettings; -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS - /*store all bytes from unknown chunks in the InfoPng (off by default, useful for a png editor)*/ - unsigned rememberUnknownChunks; -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ -} LodePNG_DecodeSettings; - -void LodePNG_DecodeSettings_init(LodePNG_DecodeSettings* settings); - -/* -The LodePNG_Decoder struct has most input and output parameters the decoder uses, -such as the settings, the info of the PNG and the raw data, and the error. Only -the pixel buffer is not contained in this struct. -*/ -typedef struct LodePNG_Decoder -{ - LodePNG_DecodeSettings settings; /*the decoding settings*/ - LodePNG_InfoRaw infoRaw; /*specifies the format in which you would like to get the raw pixel buffer*/ - LodePNG_InfoPng infoPng; /*info of the PNG image obtained after decoding*/ - unsigned error; -} LodePNG_Decoder; - -/*init, cleanup and copy functions to use with this struct*/ -void LodePNG_Decoder_init(LodePNG_Decoder* decoder); -void LodePNG_Decoder_cleanup(LodePNG_Decoder* decoder); -void LodePNG_Decoder_copy(LodePNG_Decoder* dest, const LodePNG_Decoder* source); - -/* -Decode based on a LodePNG_Decoder. -This function allocates the out buffer and stores the size in *outsize. This buffer -needs to be freed after usage. -Other information about the PNG file, such as the size, colorType and extra chunks -are stored in the infoPng field of the LodePNG_Decoder. -*/ -void LodePNG_Decoder_decode(LodePNG_Decoder* decoder, unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize); - -/* -Read the PNG header, but not the actual data. This returns only the information -that is in the header chunk of the PNG, such as width, height and color type. The -information is placed in the infoPng field of the LodePNG_Decoder. -*/ -void LodePNG_Decoder_inspect(LodePNG_Decoder* decoder, const unsigned char* in, size_t insize); +void lodepng_decoder_settings_init(LodePNGDecoderSettings* settings); #endif /*LODEPNG_COMPILE_DECODER*/ #ifdef LODEPNG_COMPILE_ENCODER -/* ////////////////////////////////////////////////////////////////////////// */ -/* LodePNG Encoder */ -/* ////////////////////////////////////////////////////////////////////////// */ +/*automatically use color type with less bits per pixel if losslessly possible. Default: AUTO*/ +typedef enum LodePNGFilterStrategy +{ + /*every filter at zero*/ + LFS_ZERO, + /*Use filter that gives minumum sum, as described in the official PNG filter heuristic.*/ + LFS_MINSUM, + /*Use the filter type that gives smallest Shannon entropy for this scanline. Depending + on the image, this is better or worse than minsum.*/ + LFS_ENTROPY, + /* + Brute-force-search PNG filters by compressing each filter for each scanline. + Experimental, very slow, and only rarely gives better compression than MINSUM. + */ + LFS_BRUTE_FORCE, + /*use predefined_filters buffer: you specify the filter type for each scanline*/ + LFS_PREDEFINED +} LodePNGFilterStrategy; + +/*automatically use color type with less bits per pixel if losslessly possible. Default: LAC_AUTO*/ +typedef enum LodePNGAutoConvert +{ + LAC_NO, /*use color type user requested*/ + LAC_ALPHA, /*use color type user requested, but if only opaque pixels and RGBA or grey+alpha, use RGB or grey*/ + LAC_AUTO, /*use PNG color type that can losslessly represent the uncompressed image the smallest possible*/ + /* + like AUTO, but do not choose 1, 2 or 4 bit per pixel types. + sometimes a PNG image compresses worse if less than 8 bits per pixels. + */ + LAC_AUTO_NO_NIBBLES, + /* + like AUTO, but never choose palette color type. For small images, encoding + the palette may take more bytes than what is gained. Note that AUTO also + already prevents encoding the palette for extremely small images, but that may + not be sufficient because due to the compression it cannot predict when to + switch. + */ + LAC_AUTO_NO_PALETTE, + LAC_AUTO_NO_NIBBLES_NO_PALETTE +} LodePNGAutoConvert; + /*Settings for the encoder.*/ -typedef struct LodePNG_EncodeSettings +typedef struct LodePNGEncoderSettings { - LodePNG_CompressSettings zlibsettings; /*settings for the zlib encoder, such as window size, ...*/ + LodePNGCompressSettings zlibsettings; /*settings for the zlib encoder, such as window size, ...*/ - /*Brute-force-search PNG filters by compressing each filter for each scanline. - This gives better compression, at the cost of being super slow. - Don't enable this for normal image saving, compression can take minutes - instead of seconds. This is experimental. If enabled, compression still isn't - as good as some other PNG encoders and optimizers, except for some images. - If you enable this, also consider setting zlibsettings.windowSize to 32768, and consider - using a less than 24-bit per pixel colorType if the image has <= 256 colors, for optimal compression. - Default: 0 (false)*/ - unsigned bruteForceFilters; + LodePNGAutoConvert auto_convert; /*how to automatically choose output PNG color type, if at all*/ + + /*If true, follows the official PNG heuristic: if the PNG uses a palette or lower than + 8 bit depth, set all filters to zero. Otherwise use the filter_strategy. Note that to + completely follow the official PNG heuristic, filter_palette_zero must be true and + filter_strategy must be LFS_MINSUM*/ + unsigned filter_palette_zero; + /*Which filter strategy to use when not using zeroes due to filter_palette_zero. + Set filter_palette_zero to 0 to ensure always using your chosen strategy. Default: LFS_MINSUM*/ + LodePNGFilterStrategy filter_strategy; + /*used if filter_strategy is LFS_PREDEFINED. In that case, this must point to a buffer with + the same length as the amount of scanlines in the image, and each value must <= 5. You + have to cleanup this buffer, LodePNG will never free it. Don't forget that filter_palette_zero + must be set to 0 to ensure this is also used on palette or low bitdepth images.*/ + unsigned char* predefined_filters; - /*automatically use color type without alpha instead of given one, if given image is opaque*/ - unsigned autoLeaveOutAlphaChannel; /*force creating a PLTE chunk if colortype is 2 or 6 (= a suggested palette). If colortype is 3, PLTE is _always_ created.*/ unsigned force_palette; #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /*add LodePNG version as text chunk*/ + /*add LodePNG identifier and version as a text chunk, for debugging*/ unsigned add_id; /*encode text chunks as zTXt chunks instead of tEXt chunks, and use compression in iTXt chunks*/ unsigned text_compression; #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -} LodePNG_EncodeSettings; +} LodePNGEncoderSettings; -void LodePNG_EncodeSettings_init(LodePNG_EncodeSettings* settings); - -/* -This struct has most input and output parameters the encoder uses, -such as the settings, the info of the PNG and the raw data, and the error. Only -the pixel buffer is not contained in this struct. -*/ -typedef struct LodePNG_Encoder -{ - /*compression settings of the encoder*/ - LodePNG_EncodeSettings settings; - /*the info specified by the user is not changed by the encoder. The encoder - will try to generate a PNG close to the given info.*/ - LodePNG_InfoPng infoPng; - /*put the properties of the input raw image in here*/ - LodePNG_InfoRaw infoRaw; - /*error value filled in if error happened, or 0 if all went ok*/ - unsigned error; -} LodePNG_Encoder; - -/*init, cleanup and copy functions to use with this struct*/ -void LodePNG_Encoder_init(LodePNG_Encoder* encoder); -void LodePNG_Encoder_cleanup(LodePNG_Encoder* encoder); -void LodePNG_Encoder_copy(LodePNG_Encoder* dest, const LodePNG_Encoder* source); - -/*This function allocates the out buffer with standard malloc and stores the size in *outsize.*/ -void LodePNG_Encoder_encode(LodePNG_Encoder* encoder, unsigned char** out, size_t* outsize, - const unsigned char* image, unsigned w, unsigned h); +void lodepng_encoder_settings_init(LodePNGEncoderSettings* settings); #endif /*LODEPNG_COMPILE_ENCODER*/ -/* ////////////////////////////////////////////////////////////////////////// */ -/* Chunk Traversing Utilities */ -/* ////////////////////////////////////////////////////////////////////////// */ + +#if defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) +/*The settings, state and information for extended encoding and decoding.*/ +typedef struct LodePNGState +{ +#ifdef LODEPNG_COMPILE_DECODER + LodePNGDecoderSettings decoder; /*the decoding settings*/ +#endif /*LODEPNG_COMPILE_DECODER*/ +#ifdef LODEPNG_COMPILE_ENCODER + LodePNGEncoderSettings encoder; /*the encoding settings*/ +#endif /*LODEPNG_COMPILE_ENCODER*/ + LodePNGColorMode info_raw; /*specifies the format in which you would like to get the raw pixel buffer*/ + LodePNGInfo info_png; /*info of the PNG image obtained after decoding*/ + unsigned error; +#ifdef LODEPNG_COMPILE_CPP + //For the lodepng::State subclass. + virtual ~LodePNGState(){} +#endif +} LodePNGState; + +/*init, cleanup and copy functions to use with this struct*/ +void lodepng_state_init(LodePNGState* state); +void lodepng_state_cleanup(LodePNGState* state); +void lodepng_state_copy(LodePNGState* dest, const LodePNGState* source); +#endif /* defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) */ + +#ifdef LODEPNG_COMPILE_DECODER +/* +Same as lodepng_decode_memory, but uses a LodePNGState to allow custom settings and +getting much more information about the PNG image and color mode. +*/ +unsigned lodepng_decode(unsigned char** out, unsigned* w, unsigned* h, + LodePNGState* state, + const unsigned char* in, size_t insize); /* -LodePNG_chunk functions: -These functions need as input a large enough amount of allocated memory. -These functions can be used on raw PNG data, but they are exposed in the API -because they are needed if you want to traverse the unknown chunks stored -in the LodePNG_UnknownChunks struct, or add new ones to it. +Read the PNG header, but not the actual data. This returns only the information +that is in the header chunk of the PNG, such as width, height and color type. The +information is placed in the info_png field of the LodePNGState. +*/ +unsigned lodepng_inspect(unsigned* w, unsigned* h, + LodePNGState* state, + const unsigned char* in, size_t insize); +#endif /*LODEPNG_COMPILE_DECODER*/ + + +#ifdef LODEPNG_COMPILE_ENCODER +/*This function allocates the out buffer with standard malloc and stores the size in *outsize.*/ +unsigned lodepng_encode(unsigned char** out, size_t* outsize, + const unsigned char* image, unsigned w, unsigned h, + LodePNGState* state); +#endif /*LODEPNG_COMPILE_ENCODER*/ + +/* +The lodepng_chunk functions are normally not needed, except to traverse the +unknown chunks stored in the LodePNGInfo struct, or add new ones to it. +It also allows traversing the chunks of an encoded PNG file yourself. + +PNG standard chunk naming conventions: +First byte: uppercase = critical, lowercase = ancillary +Second byte: uppercase = public, lowercase = private +Third byte: must be uppercase +Fourth byte: uppercase = unsafe to copy, lowercase = safe to copy */ /*get the length of the data of the chunk. Total chunk length has 12 bytes more.*/ -unsigned LodePNG_chunk_length(const unsigned char* chunk); +unsigned lodepng_chunk_length(const unsigned char* chunk); /*puts the 4-byte type in null terminated string*/ -void LodePNG_chunk_type(char type[5], const unsigned char* chunk); +void lodepng_chunk_type(char type[5], const unsigned char* chunk); /*check if the type is the given type*/ -unsigned char LodePNG_chunk_type_equals(const unsigned char* chunk, const char* type); +unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type); -/* -These functions get properties of PNG chunks gotten from capitalization of chunk -type name, as defined by the PNG standard. -*/ +/*0: it's one of the critical chunk types, 1: it's an ancillary chunk (see PNG standard)*/ +unsigned char lodepng_chunk_ancillary(const unsigned char* chunk); -/* -properties of PNG chunks gotten from capitalization of chunk type name, as defined by the standard -0: ancillary chunk, 1: it's one of the critical chunk types -*/ -unsigned char LodePNG_chunk_critical(const unsigned char* chunk); +/*0: public, 1: private (see PNG standard)*/ +unsigned char lodepng_chunk_private(const unsigned char* chunk); -/*0: public, 1: private*/ -unsigned char LodePNG_chunk_private(const unsigned char* chunk); +/*0: the chunk is unsafe to copy, 1: the chunk is safe to copy (see PNG standard)*/ +unsigned char lodepng_chunk_safetocopy(const unsigned char* chunk); -/*0: the chunk is unsafe to copy, 1: the chunk is safe to copy*/ -unsigned char LodePNG_chunk_safetocopy(const unsigned char* chunk); +/*get pointer to the data of the chunk, where the input points to the header of the chunk*/ +unsigned char* lodepng_chunk_data(unsigned char* chunk); +const unsigned char* lodepng_chunk_data_const(const unsigned char* chunk); -/*get pointer to the data of the chunk*/ -unsigned char* LodePNG_chunk_data(unsigned char* chunk); - -/*get pointer to the data of the chunk*/ -const unsigned char* LodePNG_chunk_data_const(const unsigned char* chunk); - -/*returns 0 if the crc is correct, 1 if it's incorrect*/ -unsigned LodePNG_chunk_check_crc(const unsigned char* chunk); +/*returns 0 if the crc is correct, 1 if it's incorrect (0 for OK as usual!)*/ +unsigned lodepng_chunk_check_crc(const unsigned char* chunk); /*generates the correct CRC from the data and puts it in the last 4 bytes of the chunk*/ -void LodePNG_chunk_generate_crc(unsigned char* chunk); +void lodepng_chunk_generate_crc(unsigned char* chunk); /*iterate to next chunks. don't use on IEND chunk, as there is no next chunk then*/ -unsigned char* LodePNG_chunk_next(unsigned char* chunk); -const unsigned char* LodePNG_chunk_next_const(const unsigned char* chunk); +unsigned char* lodepng_chunk_next(unsigned char* chunk); +const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk); /* Appends chunk to the data in out. The given chunk should already have its chunk header. The out variable and outlength are updated to reflect the new reallocated buffer. Returns error code (0 if it went ok) */ -unsigned LodePNG_append_chunk(unsigned char** out, size_t* outlength, const unsigned char* chunk); +unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk); /* Appends new chunk to out. The chunk to append is given by giving its length, type @@ -808,15 +708,16 @@ and data separately. The type is a 4-letter string. The out variable and outlength are updated to reflect the new reallocated buffer. Returne error code (0 if it went ok) */ -unsigned LodePNG_create_chunk(unsigned char** out, size_t* outlength, unsigned length, +unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length, const char* type, const unsigned char* data); + + +/*Calculate CRC32 of buffer*/ +unsigned lodepng_crc32(const unsigned char* buf, size_t len); #endif /*LODEPNG_COMPILE_PNG*/ -#ifdef LODEPNG_COMPILE_ZLIB -/* ////////////////////////////////////////////////////////////////////////// */ -/* Zlib encoder and decoder */ -/* ////////////////////////////////////////////////////////////////////////// */ +#ifdef LODEPNG_COMPILE_ZLIB /* This zlib part can be used independently to zlib compress and decompress a buffer. It cannot be used to create gzip files however, and it only supports the @@ -824,34 +725,59 @@ part of zlib that is required for PNG, it does not support dictionaries. */ #ifdef LODEPNG_COMPILE_DECODER -/*Decompresses Zlib data. Reallocates the out buffer and appends the data. The +/*Inflate a buffer. Inflate is the decompression step of deflate. Out buffer must be freed after use.*/ +unsigned lodepng_inflate(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGDecompressSettings* settings); + +/* +Decompresses Zlib data. Reallocates the out buffer and appends the data. The data must be according to the zlib specification. Either, *out must be NULL and *outsize must be 0, or, *out must be a valid -buffer and *outsize its size in bytes. out must be freed by user after usage.*/ -unsigned LodePNG_zlib_decompress(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, const LodePNG_DecompressSettings* settings); +buffer and *outsize its size in bytes. out must be freed by user after usage. +*/ +unsigned lodepng_zlib_decompress(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGDecompressSettings* settings); #endif /*LODEPNG_COMPILE_DECODER*/ #ifdef LODEPNG_COMPILE_ENCODER -/*Compresses data with Zlib. Reallocates the out buffer and appends the data. +/* +Compresses data with Zlib. Reallocates the out buffer and appends the data. +Zlib adds a small header and trailer around the deflate data. The data is output in the format of the zlib specification. Either, *out must be NULL and *outsize must be 0, or, *out must be a valid -buffer and *outsize its size in bytes. out must be freed by user after usage.*/ -unsigned LodePNG_zlib_compress(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, const LodePNG_CompressSettings* settings); +buffer and *outsize its size in bytes. out must be freed by user after usage. +*/ +unsigned lodepng_zlib_compress(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGCompressSettings* settings); + +/* +Find length-limited Huffman code for given frequencies. This function is in the +public interface only for tests, it's used internally by lodepng_deflate. +*/ +unsigned lodepng_huffman_code_lengths(unsigned* lengths, const unsigned* frequencies, + size_t numcodes, unsigned maxbitlen); + +/*Compress a buffer with deflate. See RFC 1951. Out buffer must be freed after use.*/ +unsigned lodepng_deflate(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGCompressSettings* settings); + #endif /*LODEPNG_COMPILE_ENCODER*/ #endif /*LODEPNG_COMPILE_ZLIB*/ #ifdef LODEPNG_COMPILE_DISK /* Load a file from disk into buffer. The function allocates the out buffer, and -after usage you are responsible for freeing it. +after usage you should free it. out: output parameter, contains pointer to loaded buffer. outsize: output parameter, size of the allocated out buffer filename: the path to the file to load return value: error code (0 means ok) */ -unsigned LodePNG_loadFile(unsigned char** out, size_t* outsize, const char* filename); +unsigned lodepng_load_file(unsigned char** out, size_t* outsize, const char* filename); /* Save a file from buffer to disk. Warning, if it exists, this function overwrites @@ -861,188 +787,91 @@ buffersize: size of the buffer to write filename: the path to the file to save to return value: error code (0 means ok) */ -unsigned LodePNG_saveFile(const unsigned char* buffer, size_t buffersize, const char* filename); +unsigned lodepng_save_file(const unsigned char* buffer, size_t buffersize, const char* filename); #endif /*LODEPNG_COMPILE_DISK*/ -#ifdef __cplusplus -/* ////////////////////////////////////////////////////////////////////////// */ -/* LodePNG C++ wrapper */ -/* ////////////////////////////////////////////////////////////////////////// */ - -//The LodePNG C++ wrapper uses classes with handy constructors and destructors -//instead of manual init and cleanup functions, and uses std::vectors instead of -//manually allocated memory buffers. - -namespace LodePNG +#ifdef LODEPNG_COMPILE_CPP +//The LodePNG C++ wrapper uses std::vectors instead of manually allocated memory buffers. +namespace lodepng { -#ifdef LODEPNG_COMPILE_ZLIB -//The C++ wrapper for the zlib part -#ifdef LODEPNG_COMPILE_DECODER - //Zlib-decompress an unsigned char buffer - unsigned decompress(std::vector& out, const unsigned char* in, size_t insize, - const LodePNG_DecompressSettings& settings = LodePNG_defaultDecompressSettings); - - //Zlib-decompress an std::vector - unsigned decompress(std::vector& out, const std::vector& in, - const LodePNG_DecompressSettings& settings = LodePNG_defaultDecompressSettings); -#endif //LODEPNG_COMPILE_DECODER - -#ifdef LODEPNG_COMPILE_ENCODER - //Zlib-compress an unsigned char buffer - unsigned compress(std::vector& out, const unsigned char* in, size_t insize, - const LodePNG_CompressSettings& settings = LodePNG_defaultCompressSettings); - - //Zlib-compress an std::vector - unsigned compress(std::vector& out, const std::vector& in, - const LodePNG_CompressSettings& settings = LodePNG_defaultCompressSettings); -#endif //LODEPNG_COMPILE_ENCODER -#endif //LODEPNG_COMPILE_ZLIB - #ifdef LODEPNG_COMPILE_PNG +class State : public LodePNGState +{ + public: + State(); + State(const State& other); + virtual ~State(); + State& operator=(const State& other); +}; + #ifdef LODEPNG_COMPILE_DECODER - /* - Class to decode a PNG image. Before decoding, settings can be set and - after decoding, extra information about the PNG can be retrieved. - Extends from the C-struct LodePNG_Decoder to add constructors and destructors - to initialize/cleanup it automatically. Beware, no virtual destructor is used. - */ - class Decoder : public LodePNG_Decoder - { - public: - - Decoder(); - ~Decoder(); - void operator=(const LodePNG_Decoder& other); - - //decode PNG buffer to raw out buffer. Width and height can be retrieved with getWidth() and - //getHeight() and error should be checked with hasError() and getError() - void decode(std::vector& out, const unsigned char* in, size_t insize); - - //decode PNG buffer to raw out buffer. Width and height can be retrieved with getWidth() and - //getHeight() and error should be checked with hasError() and getError() - void decode(std::vector& out, const std::vector& in); - - //inspect functions: get only the info from the PNG header. The info can then be retrieved with - //the functions of this class. - void inspect(const unsigned char* in, size_t insize); - - //inspect functions: get only the info from the PNG header. The info can then be retrieved with - //the functions of this class. - void inspect(const std::vector& in); - - //error checking after decoding - bool hasError() const; - unsigned getError() const; - - //convenient access to some InfoPng parameters after decoding - unsigned getWidth() const; //width of image in pixels - unsigned getHeight() const; //height of image in pixels - unsigned getBpp(); //bits per pixel - unsigned getChannels(); //amount of channels - unsigned isGreyscaleType(); //is it a greyscale type? (colorType 0 or 4) - unsigned isAlphaType(); //has it an alpha channel? (colorType 2 or 6) - - //getters and setters for the decoding settings - const LodePNG_DecodeSettings& getSettings() const; - LodePNG_DecodeSettings& getSettings(); - void setSettings(const LodePNG_DecodeSettings& info); - - //getters and setters for the PNG image info, after decoding this describes information of the PNG image - const LodePNG_InfoPng& getInfoPng() const; - LodePNG_InfoPng& getInfoPng(); - void setInfoPng(const LodePNG_InfoPng& info); - void swapInfoPng(LodePNG_InfoPng& info); //faster than copying with setInfoPng - - //getters and setters for the raw image info, this determines in what format - //you get the pixel buffer from the decoder - const LodePNG_InfoRaw& getInfoRaw() const; - LodePNG_InfoRaw& getInfoRaw(); - void setInfoRaw(const LodePNG_InfoRaw& info); - }; -#endif //LODEPNG_COMPILE_DECODER +//Same as other lodepng::decode, but using a State for more settings and information. +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + State& state, + const unsigned char* in, size_t insize); +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + State& state, + const std::vector& in); +#endif /*LODEPNG_COMPILE_DECODER*/ #ifdef LODEPNG_COMPILE_ENCODER - /* - Class to encode a PNG image. Before encoding, settings can be set. - Extends from the C-struct LodePNG_Enoder to add constructors and destructors - to initialize/cleanup it automatically. Beware, no virtual destructor is used. - */ - class Encoder : public LodePNG_Encoder - { - public: - - Encoder(); - ~Encoder(); - void operator=(const LodePNG_Encoder& other); - - //encoding image to PNG buffer - void encode(std::vector& out, const unsigned char* image, unsigned w, unsigned h); - - //encoding image to PNG buffer - void encode(std::vector& out, const std::vector& image, unsigned w, unsigned h); - - //error checking after decoding - bool hasError() const; - unsigned getError() const; - - //convenient direct access to some parameters of the InfoPng - void clearPalette(); - void addPalette(unsigned char r, unsigned char g, unsigned char b, unsigned char a); //add 1 color to the palette -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - void clearText(); - void addText(const std::string& key, const std::string& str); //push back both texts at once - void clearIText(); - void addIText(const std::string& key, const std::string& langtag, - const std::string& transkey, const std::string& str); -#endif //LODEPNG_COMPILE_ANCILLARY_CHUNKS - - //getters and setters for the encoding settings - const LodePNG_EncodeSettings& getSettings() const; - LodePNG_EncodeSettings& getSettings(); - void setSettings(const LodePNG_EncodeSettings& info); - - //getters and setters for the PNG image info, this describes what color type - //and other settings the resulting PNG should have - const LodePNG_InfoPng& getInfoPng() const; - LodePNG_InfoPng& getInfoPng(); - void setInfoPng(const LodePNG_InfoPng& info); - void swapInfoPng(LodePNG_InfoPng& info); //faster than copying with setInfoPng - - //getters and setters for the raw image info, this describes how the encoder - //should interpret the input pixel buffer - const LodePNG_InfoRaw& getInfoRaw() const; - LodePNG_InfoRaw& getInfoRaw(); - void setInfoRaw(const LodePNG_InfoRaw& info); - }; -#endif //LODEPNG_COMPILE_ENCODER +//Same as other lodepng::encode, but using a State for more settings and information. +unsigned encode(std::vector& out, + const unsigned char* in, unsigned w, unsigned h, + State& state); +unsigned encode(std::vector& out, + const std::vector& in, unsigned w, unsigned h, + State& state); +#endif /*LODEPNG_COMPILE_ENCODER*/ #ifdef LODEPNG_COMPILE_DISK - /* - Load a file from disk into an std::vector. If the vector is empty, then either - the file doesn't exist or is an empty file. - */ - void loadFile(std::vector& buffer, const std::string& filename); +/* +Load a file from disk into an std::vector. If the vector is empty, then either +the file doesn't exist or is an empty file. +*/ +void load_file(std::vector& buffer, const std::string& filename); - /* - Save the binary data in an std::vector to a file on disk. The file is overwritten - without warning. - */ - void saveFile(const std::vector& buffer, const std::string& filename); +/* +Save the binary data in an std::vector to a file on disk. The file is overwritten +without warning. +*/ +void save_file(const std::vector& buffer, const std::string& filename); #endif //LODEPNG_COMPILE_DISK #endif //LODEPNG_COMPILE_PNG -} //namespace LodePNG -#endif /*end of __cplusplus wrapper*/ + +#ifdef LODEPNG_COMPILE_ZLIB +#ifdef LODEPNG_COMPILE_DECODER +//Zlib-decompress an unsigned char buffer +unsigned decompress(std::vector& out, const unsigned char* in, size_t insize, + const LodePNGDecompressSettings& settings = lodepng_default_decompress_settings); + +//Zlib-decompress an std::vector +unsigned decompress(std::vector& out, const std::vector& in, + const LodePNGDecompressSettings& settings = lodepng_default_decompress_settings); +#endif //LODEPNG_COMPILE_DECODER + +#ifdef LODEPNG_COMPILE_ENCODER +//Zlib-compress an unsigned char buffer +unsigned compress(std::vector& out, const unsigned char* in, size_t insize, + const LodePNGCompressSettings& settings = lodepng_default_compress_settings); + +//Zlib-compress an std::vector +unsigned compress(std::vector& out, const std::vector& in, + const LodePNGCompressSettings& settings = lodepng_default_compress_settings); +#endif //LODEPNG_COMPILE_ENCODER +#endif //LODEPNG_COMPILE_ZLIB +} //namespace lodepng +#endif /*LODEPNG_COMPILE_CPP*/ /* TODO: [.] test if there are no memory leaks or security exploits - done a lot but needs to be checked often [.] check compatibility with vareous compilers - done but needs to be redone for every newer version -[ ] LZ77 encoder more like the one described in zlib - to make sure it's patentfree [X] converting color to 16-bit per channel types [ ] read all public PNG chunk types (but never let the color profile and gamma ones touch RGB values) [ ] make sure encoder generates no chunks with size > (2^31)-1 [ ] partial decoding (stream processing) -[ ] let the "isFullyOpaque" function check color keys and transparent palettes too +[X] let the "isFullyOpaque" function check color keys and transparent palettes too [X] better name for the variables "codes", "codesD", "codelengthcodes", "clcl" and "lldl" [ ] don't stop decoding on errors like 69, 57, 58 (make warnings) [ ] make option to choose if the raw image with non multiple of 8 bits per scanline should have padding bits or not @@ -1055,9 +884,6 @@ TODO: LodePNG Documentation --------------------- -This documentations contains background information and examples. For the function -and class documentation, see the comments in the declarations above. - 0. table of contents -------------------- @@ -1070,16 +896,15 @@ and class documentation, see the comments in the declarations above. 5. encoding 6. color conversions 6.1. PNG color types - 6.2. Default Behaviour of LodePNG - 6.3. Color Conversions - 6.4. More Notes + 6.2. color conversions + 6.3. padding bits + 6.4. A note about 16-bits per channel and endianness 7. error values 8. chunks and PNG editing 9. compiler support 10. examples 10.1. decoder C++ example - 10.2. encoder C++ example - 10.3. decoder C example + 10.2. decoder C example 11. changes 12. contact information @@ -1088,7 +913,7 @@ and class documentation, see the comments in the declarations above. -------- PNG is a file format to store raster images losslessly with good compression, -supporting different color types. It can be implemented in a patent-free way. +supporting different color types and alpha channel. LodePNG is a PNG codec according to the Portable Network Graphics (PNG) Specification (Second Edition) - W3C Recommendation 10 November 2003. @@ -1103,7 +928,7 @@ The specifications used are: http://www.gzip.org/zlib/rfc-deflate.html The most recent version of LodePNG can currently be found at -http://members.gamedev.net/lode/projects/LodePNG/ +http://lodev.org/lodepng/ LodePNG works both in C (ISO C90) and C++, with a C++ wrapper that adds extra functionality. @@ -1113,24 +938,22 @@ LodePNG exists out of two files: -lodepng.c(pp): give it the name lodepng.c or lodepng.cpp (or .cc) depending on your usage If you want to start using LodePNG right away without reading this doc, get the -files lodepng_examples.c or lodepng_examples.cpp to see how to use it in code, -or check the (smaller) examples in chapter 13 here. +examples from the LodePNG website to see how to use it in code, or check the +smaller examples in chapter 13 here. LodePNG is simple but only supports the basic requirements. To achieve simplicity, the following design choices were made: There are no dependencies -on any external library. To decode PNGs, there's a Decoder struct or class that -can convert any PNG file data into an RGBA image buffer with a single function -call. To encode PNGs, there's an Encoder struct or class that can convert image -data into PNG file data with a single function call. To read and write files, -there are simple functions to convert the files to/from buffers in memory. +on any external library. There are functions to decode and encode a PNG with +a single function call, and extended versions of these functions taking a +LodePNGState struct allowing to specify or get more information. By default +the colors of the raw image are always RGB or RGBA, no matter what color type +the PNG file uses. To read and write files, there are simple functions to +convert the files to/from buffers in memory. -This all makes LodePNG suitable for loading textures in games, demoscene -productions, saving a screenshot, images in programs that require them for simple -usage, ... It's less suitable for full fledged image editors, loading PNGs +This all makes LodePNG suitable for loading textures in games, demos and small +programs, ... It's less suitable for full fledged image editors, loading PNGs over network (it requires all the image data to be available before decoding can begin), life-critical systems, ... -LodePNG has a standards conformant decoder and encoder, and supports the ability -to make a somewhat conformant editor. 1.1. supported features ----------------------- @@ -1169,27 +992,26 @@ The following features are _not_ supported: *) partial loading/stream processing. All data must be available and is processed in one call. *) The following public chunks are not supported but treated as unknown chunks by LodePNG cHRM, gAMA, iCCP, sRGB, sBIT, hIST, sPLT + Some of these are not supported on purpose: LodePNG wants to provide the RGB values + stored in the pixels, not values modified by system dependent gamma or color models. 2. C and C++ version -------------------- The C version uses buffers allocated with alloc that you need to free() -yourself. On top of that, you need to use init and cleanup functions for each -struct whenever using a struct from the C version to avoid exploits and memory leaks. +yourself. You need to use init and cleanup functions for each struct whenever +using a struct from the C version to avoid exploits and memory leaks. -The C++ version has constructors and destructors that take care of these things, -and uses std::vectors in the interface for storing data. +The C++ version has extra functions with std::vectors in the interface and the +lodepng::State class which is a LodePNGState with constructor and destructor. -Both the C and the C++ version are contained in this file! The C++ code depends on -the C code, the C code works on its own. +These files work without modification for both C and C++ compilers because all +the additional C++ code is in "#ifdef __cplusplus" blocks that make C-compilers +ignore it, and the C code is made to compile both with strict ISO C90 and C++. -These files work without modification for both C and C++ compilers because all the -additional C++ code is in "#ifdef __cplusplus" blocks that make C-compilers ignore -it, and the C code is made to compile both with strict ISO C90 and C++. - -To use the C++ version, you need to rename the source file to lodepng.cpp (instead -of lodepng.c), and compile it with a C++ compiler. +To use the C++ version, you need to rename the source file to lodepng.cpp +(instead of lodepng.c), and compile it with a C++ compiler. To use the C version, you need to rename the source file to lodepng.c (instead of lodepng.cpp), and compile it with a C compiler. @@ -1198,18 +1020,18 @@ of lodepng.cpp), and compile it with a C compiler. 3. Security ----------- -As with most software, even if carefully designed, it's always possible that -LodePNG may contain possible exploits. +Even if carefully designed, it's always possible that LodePNG contains possible +exploits. If you discover one, please let me know, and it will be fixed. -If you discover a possible exploit, please let me know, and it will be fixed. +When using LodePNG, care has to be taken with the C version of LodePNG, as well +as the C-style structs when working with C++. The following conventions are used +for all C-style structs: -When using LodePNG, care has to be taken with the C version of LodePNG, as well as the C-style -structs when working with C++. The following conventions are used for all C-style structs: - --if a struct has a corresponding init function, always call the init function when making a new one, to avoid exploits +-if a struct has a corresponding init function, always call the init function when making a new one -if a struct has a corresponding cleanup function, call it before the struct disappears to avoid memory leaks -if a struct has a corresponding copy function, use the copy function instead of "=". - The destination must also be inited already! + The destination must also be inited already. + 4. Decoding ----------- @@ -1217,57 +1039,49 @@ structs when working with C++. The following conventions are used for all C-styl Decoding converts a PNG compressed image to a raw pixel buffer. Most documentation on using the decoder is at its declarations in the header -above. For C, simple decoding can be done with functions such as LodePNG_decode32, -and more advanced decoding can be done with the struct LodePNG_Decoder and its -functions. For C++, simple decoding can be done with the LodePNG::decode functions -and advanced decoding with the LodePNG::Decoder class. +above. For C, simple decoding can be done with functions such as +lodepng_decode32, and more advanced decoding can be done with the struct +LodePNGState and lodepng_decode. For C++, all decoding can be done with the +various lodepng::decode functions, and lodepng::State can be used for advanced +features. -The Decoder contains 3 components: -*) LodePNG_InfoPng: it stores information about the PNG (the input) in an LodePNG_InfoPng struct, - don't modify this one yourself -*) Settings: you can specify a few other settings for the decoder to use -*) LodePNG_InfoRaw: here you can say what type of raw image (the output) you want to get +When using the LodePNGState, it uses the following fields for decoding: +*) LodePNGInfo info_png: it stores extra information about the PNG (the input) in here +*) LodePNGColorMode info_raw: here you can say what color mode of the raw image (the output) you want to get +*) LodePNGDecoderSettings decoder: you can specify a few extra settings for the decoder to use -Some of the parameters described below may be inside the sub-struct "LodePNG_InfoColor color". -In the C and C++ version, when using Info structs outside of the decoder or encoder, you need to use their -init and cleanup functions, but normally you use the ones in the decoder that are already handled -in the init and cleanup functions of the decoder itself. +LodePNGInfo info_png +-------------------- -=LodePNG_InfoPng= +After decoding, this contains extra information of the PNG image, except the actual +pixels, width and height because these are already gotten directly from the decoder +functions. -This contains information such as the original color type of the PNG image, text -comments, suggested background color, etc... More details about the LodePNG_InfoPng struct -are at its declaration documentation. +It contains for example the original color type of the PNG image, text comments, +suggested background color, etc... More details about the LodePNGInfo struct are +at its declaration documentation. -Because the dimensions of the image are important, there are shortcuts to get them in the -C++ version: use decoder.getWidth() and decoder.getHeight(). -In the C version, use decoder.infoPng.width and decoder.infoPng.height. +LodePNGColorMode info_raw +------------------------- -=LodePNG_InfoRaw= - -In the LodePNG_InfoRaw struct of the Decoder, you can specify which color type you want -the resulting raw image to be. If this is different from the colorType of the -PNG, then the decoder will automatically convert the result to your LodePNG_InfoRaw -settings. Not all combinations of color conversions are supported though, see -a different section for information about the color modes and supported conversions. - -Palette of LodePNG_InfoRaw isn't used by the Decoder, when converting from palette color -to palette color, the values of the pixels are left untouched so that the colors -will change if the palette is different. Color key of LodePNG_InfoRaw is not used by the -Decoder. If setting color_convert is false then LodePNG_InfoRaw is completely ignored, -but it will be modified to match the color type of the PNG so will be overwritten. +When decoding, here you can specify which color type you want +the resulting raw image to be. If this is different from the colortype of the +PNG, then the decoder will automatically convert the result. This conversion +always works, except if you want it to convert a color PNG to greyscale or to +a palette with missing colors. By default, 32-bit color is used for the result. -=Settings= +LodePNGDecoderSettings decoder +------------------------------ -The Settings can be used to ignore the errors created by invalid CRC and Adler32 +The settings can be used to ignore the errors created by invalid CRC and Adler32 chunks, and to disable the decoding of tEXt chunks. There's also a setting color_convert, true by default. If false, no conversion is done, the resulting data will be as it was in the PNG (after decompression) and you'll have to puzzle the colors of the pixels together yourself using the -color type information in the LodePNG_InfoPng. +color type information in the LodePNGInfo. 5. Encoding @@ -1276,53 +1090,41 @@ color type information in the LodePNG_InfoPng. Encoding converts a raw pixel buffer to a PNG compressed image. Most documentation on using the encoder is at its declarations in the header -above. For C, simple encoding can be done with functions such as LodePNG_encode32, -and more advanced decoding can be done with the struct LodePNG_Encoder and its -functions. For C++, simple encoding can be done with the LodePNG::encode functions -and advanced decoding with the LodePNG::Encoder class. +above. For C, simple encoding can be done with functions such as +lodepng_encode32, and more advanced decoding can be done with the struct +LodePNGState and lodepng_encode. For C++, all encoding can be done with the +various lodepng::encode functions, and lodepng::State can be used for advanced +features. Like the decoder, the encoder can also give errors. However it gives less errors since the encoder input is trusted, the decoder input (a PNG image that could be forged by anyone) is not trusted. -Like the Decoder, the Encoder has 3 components: -*) LodePNG_InfoRaw: here you say what color type of the raw image (the input) has -*) Settings: you can specify a few settings for the encoder to use -*) LodePNG_InfoPng: the same LodePNG_InfoPng struct as created by the Decoder. For the encoder, -with this you specify how you want the PNG (the output) to be. +When using the LodePNGState, it uses the following fields for encoding: +*) LodePNGInfo info_png: here you specify how you want the PNG (the output) to be. +*) LodePNGColorMode info_raw: here you say what color type of the raw image (the input) has +*) LodePNGEncoderSettings encoder: you can specify a few settings for the encoder to use -Some of the parameters described below may be inside the sub-struct "LodePNG_InfoColor color". -In the C and C++ version, when using Info structs outside of the decoder or encoder, you need to use their -init and cleanup functions, but normally you use the ones in the encoder that are already handled -in the init and cleanup functions of the decoder itself. +LodePNGInfo info_png +-------------------- -=LodePNG_InfoPng= +When encoding, you use this the opposite way as when decoding: for encoding, +you fill in the values you want the PNG to have before encoding. By default it's +not needed to specify a color type for the PNG since it's automatically chosen, +but it's possible to choose it yourself given the right settings. -The Decoder class stores information about the PNG image in an LodePNG_InfoPng object. With -the Encoder you can do the opposite: you give it an LodePNG_InfoPng object, and it'll try -to match the LodePNG_InfoPng you give as close as possible in the PNG it encodes. For -example in the LodePNG_InfoPng you can specify the color type you want to use, possible -tEXt chunks you want the PNG to contain, etc... For an explanation of all the -values in LodePNG_InfoPng see a further section. Not all PNG color types are supported -by the Encoder. +The encoder will not always exactly match the LodePNGInfo struct you give, +it tries as close as possible. Some things are ignored by the encoder. The +encoder uses, for example, the following settings from it when applicable: +colortype and bitdepth, text chunks, time chunk, the color key, the palette, the +background color, the interlace method, unknown chunks, ... -The encoder will not always exactly match the LodePNG_InfoPng struct you give, -it tries as close as possible. Some things are ignored by the encoder. The width -and height of LodePNG_InfoPng are ignored as well, because instead the width and -height of the raw image you give in the input are used. In fact the encoder -currently uses only the following settings from it: --colorType and bitDepth: the ones it supports --text chunks, that you can add to the LodePNG_InfoPng with "addText" --the color key, if applicable for the given color type --the palette, if you encode to a PNG with colorType 3 --the background color: it'll add a bKGD chunk to the PNG if one is given --the interlaceMethod: None (0) or Adam7 (1) - -When encoding to a PNG with colorType 3, the encoder will generate a PLTE chunk. +When encoding to a PNG with colortype 3, the encoder will generate a PLTE chunk. If the palette contains any colors for which the alpha channel is not 255 (so there are translucent colors in the palette), it'll add a tRNS chunk. -=LodePNG_InfoRaw= +LodePNGColorMode info_raw +------------------------- You specify the color type of the raw image that you give to the input here, including a possible transparent color key and palette you happen to be using in @@ -1331,23 +1133,25 @@ your raw image data. By default, 32-bit color is assumed, meaning your input has to be in RGBA format with 4 bytes (unsigned chars) per pixel. -=Settings= +LodePNGEncoderSettings encoder +------------------------------ The following settings are supported (some are in sub-structs): -*) autoLeaveOutAlphaChannel: when this option is enabled, when you specify a PNG -color type with alpha channel (not to be confused with the color type of the raw -image you specify!!), but the encoder detects that all pixels of the given image -are opaque, then it'll automatically use the corresponding type without alpha -channel, resulting in a smaller PNG image. -*) btype: the block type for LZ77. - 0 = uncompressed, 1 = fixed huffman tree, 2 = dynamic huffman tree (best compression) -*) useLZ77: whether or not to use LZ77 for compressed block types -*) windowSize: the window size used by the LZ77 encoder (1 - 32768) -*) force_palette: if colorType is 2 or 6, you can make the encoder write a PLTE +*) auto_convert: when this option is enabled, the encoder will +automatically choose the smallest possible color mode (including color key) that +can encode the colors of all pixels without information loss. +*) btype: the block type for LZ77. 0 = uncompressed, 1 = fixed huffman tree, + 2 = dynamic huffman tree (best compression). Should be 2 for proper + compression. +*) use_lz77: whether or not to use LZ77 for compressed block types. Should be + true for proper compression. +*) windowsize: the window size used by the LZ77 encoder (1 - 32768). Has value + 2048 by default, but can be set to 32768 for better, but slow, compression. +*) force_palette: if colortype is 2 or 6, you can make the encoder write a PLTE chunk if force_palette is true. This can used as suggested palette to convert to by viewers that don't support more than 256 colors (if those still exist) *) add_id: add text chunk "Encoder: LodePNG " to the image. -*) text_compression: default 0. If 1, it'll store texts as zTXt instead of tEXt chunks. +*) text_compression: default 1. If 1, it'll store texts as zTXt instead of tEXt chunks. zTXt chunks use zlib compression on the text. This gives a smaller result on large texts but a larger result on small texts (such as a single program name). It's all tEXt or all zTXt though, there's no separate setting per text yet. @@ -1356,13 +1160,29 @@ channel, resulting in a smaller PNG image. 6. color conversions -------------------- -In LodePNG, the color mode (bits, channels and palette) used in the PNG image, -and the color mode used in the raw data, are separate and independently -configurable. Therefore, LodePNG needs to do conversions from one color mode to -another. Not all possible conversions are supported (e.g. converting to a palette -or a lower bit depth isn't supported). This section will explain which conversions -are supported and how to configure this. This explains for example when LodePNG -uses the settings in LodePNG_InfoPng, LodePNG_InfoRaw and Settings. +An important thing to note about LodePNG, is that the color type of the PNG, and +the color type of the raw image, are completely independent. By default, when +you decode a PNG, you get the result as a raw image in the color type you want, +no matter whether the PNG was encoded with a palette, greyscale or RGBA color. +And if you encode an image, by default LodePNG will automatically choose the PNG +color type that gives good compression based on the values of colors and amount +of colors in the image. It can be configured to let you control it instead as +well, though. + +To be able to do this, LodePNG does conversions from one color mode to another. +It can convert from almost any color type to any other color type, except the +following conversions: RGB to greyscale is not supported, and converting to a +palette when the palette doesn't have a required color is not supported. This is +not supported on purpose: this is information loss which requires a color +reduction algorithm that is beyong the scope of a PNG encoder (yes, RGB to grey +is easy, but there are multiple ways if you want to give some channels more +weight). + +By default, when decoding, you get the raw image in 32-bit RGBA or 24-bit RGB +color, no matter what color type the PNG has. And by default when encoding, +LodePNG automatically picks the best color model for the output PNG, and expects +the input image to be 32-bit RGBA or 24-bit RGB. So, unless you want to control +the color format of the images yourself, you can skip this chapter. 6.1. PNG color types -------------------- @@ -1373,7 +1193,7 @@ in the PNG image is done, the raw pixel data will have that color type and thus a certain amount of bits per pixel. If you want the output raw image after decoding to have another color type, a conversion is done by LodePNG. -The PNG specification mentions the following color types: +The PNG specification gives the following color types: 0: greyscale, bit depths 1, 2, 4, 8, 16 2: RGB, bit depths 8 and 16 @@ -1382,109 +1202,124 @@ The PNG specification mentions the following color types: 6: RGBA, bit depths 8 and 16 Bit depth is the amount of bits per pixel per color channel. So the total amount -of bits per pixel = amount of channels * bitDepth. +of bits per pixel is: amount of channels * bitdepth. -6.2. Default Behaviour of LodePNG ---------------------------------- - -By default, the Decoder will convert the data from the PNG to 32-bit RGBA color, -no matter what color type the PNG has, so that the result can be used directly -as a texture in OpenGL etc... without worries about what color type the original -image has. - -The Encoder assumes by default that the raw input you give it is a 32-bit RGBA -buffer and will store the PNG as either 32 bit or 24 bit depending on whether -or not any translucent pixels were detected in it. - -To get the default behaviour, don't change the values of LodePNG_InfoRaw and -LodePNG_InfoPng of the encoder, and don't change the values of LodePNG_InfoRaw -of the decoder. - -6.3. Color Conversions +6.2. color conversions ---------------------- -As explained in the sections about the Encoder and Decoder, you can specify -color types and bit depths in LodePNG_InfoPng and LodePNG_InfoRaw, to change the default behaviour -explained above. (for the Decoder you can only specify the LodePNG_InfoRaw, because the -LodePNG_InfoPng contains what the PNG file has). +As explained in the sections about the encoder and decoder, you can specify +color types and bit depths in info_png and info_raw to change the default +behaviour. + +If, when decoding, you want the raw image to be something else than the default, +you need to set the color type and bit depth you want in the LodePNGColorMode, +or the parameters of the simple function of LodePNG you're using. + +If, when encoding, you use another color type than the default in the input +image, you need to specify its color type and bit depth in the LodePNGColorMode +of the raw image, or use the parameters of the simplefunction of LodePNG you're +using. + +If, when encoding, you don't want LodePNG to choose the output PNG color type +but control it yourself, you need to set auto_convert in the encoder settings +to LAC_NONE, and specify the color type you want in the LodePNGInfo of the +encoder. + +If you do any of the above, LodePNG may need to do a color conversion, which +follows the rules below, and may sometimes not be allowed. To avoid some confusion: --the Decoder converts from PNG to raw image --the Encoder converts from raw image to PNG --the color type and bit depth in LodePNG_InfoRaw, are those of the raw image --the color type and bit depth in LodePNG_InfoPng, are those of the PNG --if the color type of the LodePNG_InfoRaw and PNG image aren't the same, a conversion -between the color types is done if the color types are supported. If it is not -supported, an error is returned. If the types are the same, no conversion is done -and this is supported for any color type. +-the decoder converts from PNG to raw image +-the encoder converts from raw image to PNG +-the colortype and bitdepth in LodePNGColorMode info_raw, are those of the raw image +-the colortype and bitdepth in the color field of LodePNGInfo info_png, are those of the PNG +-when encoding, the color type in LodePNGInfo is ignored if auto_convert + is enabled, it is automatically generated instead +-when decoding, the color type in LodePNGInfo is set by the decoder to that of the original + PNG image, but it can be ignored since the raw image has the color type you requested instead +-if the color type of the LodePNGColorMode and PNG image aren't the same, a conversion + between the color types is done if the color types are supported. If it is not + supported, an error is returned. If the types are the same, no conversion is done. +-even though some conversions aren't supported, LodePNG supports loading PNGs from any + colortype and saving PNGs to any colortype, sometimes it just requires preparing + the raw image correctly before encoding. +-both encoder and decoder use the same color converter. + +Non supported color conversions: +-color to greyscale: no error is thrown, but the result will look ugly because +only the red channel is taken +-anything, to palette when that palette does not have that color in it: in this +case an error is thrown Supported color conversions: --It's possible to load PNGs from any colortype and to save PNGs of any colorType. --Both encoder and decoder use the same converter. So both encoder and decoder -suport the same color types at the input and the output. So the decoder supports -any type of PNG image and can convert it to certain types of raw image, while the -encoder supports any type of raw data but only certain color types for the output PNG. --The converter can convert from _any_ input color type, to 24-bit RGB or 32-bit RGBA (8 bits per channel) --The converter can convert from _any_ input color type, to 48-bit RGB or 64-bit RGBA (16 bits per channel) --The converter can convert from greyscale input color type, to 8-bit greyscale or greyscale with alpha --The converter can convert from greyscale input color type, to 16-bit greyscale or greyscale with alpha --If both color types are the same, conversion from anything to anything is possible --Color types that are invalid according to the PNG specification are not allowed --When converting from a type with alpha channel to one without, the alpha channel information is discarded --When converting from a type without alpha channel to one with, the result will be opaque except - pixels that have the same color as the color key of the input if one was given --When converting from 16-bit bitDepth to 8-bit bitDepth, the 16-bit precision information is lost, - only the most significant byte is kept --When converting from 8-bit bitDepth to 16-bit bitDepth, the 8-bit byte is duplicated, so that 0 stays 0, and - the 8-bit maximum 255 is converted to the 16-bit maximum 65535. Something similar happens at bit level for - converting very low bit depths to 8 or 16 bit. --Converting from color to greyscale or to palette is not supported on purpose: there are multiple possible - algorithms to do this color reduction, LodePNG does not want to pick one and leaves this choice to the - user instead, because it's beyond the scope of PNG encoding. --Converting from a palette to a palette, only keeps the indices, it ignores the colors defined in the - palette without giving an error +-anything to 8-bit RGB, 8-bit RGBA, 16-bit RGB, 16-bit RGBA +-any grey or grey+alpha, to grey or grey+alpha +-anything to a palette, as long as the palette has the requested colors in it +-removing alpha channel +-higher to smaller bitdepth, and vice versa -No conversion needed...: --If the color type of the PNG image and raw image are the same, then no -conversion is done, and all color types are supported. --In the encoder, you can make it save a PNG with any color by giving the -LodePNG_InfoRaw and LodePNG_InfoPng the same color type. +If you want no color conversion to be done: +-In the encoder, you can make it save a PNG with any color type by giving the +raw color mode and LodePNGInfo the same color mode, and setting auto_convert to +LAC_NO. -In the decoder, you can make it store the pixel data in the same color type as the PNG has, by setting the color_convert setting to false. Settings in -infoRaw are then ignored. +info_raw are then ignored. -The function LodePNG_convert does this, which is available in the interface but -normally isn't needed since the encoder and decoder already call it. +The function lodepng_convert does the color conversion. It is available in the +interface but normally isn't needed since the encoder and decoder already call +it. -6.4. More Notes ---------------- +6.3. padding bits +----------------- In the PNG file format, if a less than 8-bit per pixel color type is used and the scanlines have a bit amount that isn't a multiple of 8, then padding bits are used so that each -scanline starts at a fresh byte. But that is NOT true for the LodePNG input and output! +scanline starts at a fresh byte. But that is NOT true for the LodePNG raw input and output. The raw input image you give to the encoder, and the raw output image you get from the decoder will NOT have these padding bits, e.g. in the case of a 1-bit image with a width of 7 pixels, the first pixel of the second scanline will the the 8th bit of the first byte, not the first bit of a new byte. +6.4. A note about 16-bits per channel and endianness +---------------------------------------------------- + +LodePNG uses unsigned char arrays for 16-bit per channel colors too, just like +for any other color format. The 16-bit values are stored in big endian (most +significant byte first) in these arrays. This is the opposite order of the +little endian used by x86 CPU's. + +LodePNG always uses big endian because the PNG file format does so internally. +Conversions to other formats than PNG uses internally are not supported by +LodePNG on purpose, there are myriads of formats, including endianness of 16-bit +colors, the order in which you store R, G, B and A, and so on. Supporting and +converting to/from all that is outside the scope of LodePNG. + +This may mean that, depending on your use case, you may want to convert the big +endian output of LodePNG to little endian with a for loop. This is certainly not +always needed, many applications and libraries support big endian 16-bit colors +anyway, but it means you cannot simply cast the unsigned char* buffer to an +unsigned short* buffer on x86 CPUs. + + 7. error values --------------- All functions in LodePNG that return an error code, return 0 if everything went -OK, or one of the code defined by LodePNG if there was an error. +OK, or a non-zero code if there was an error. The meaning of the LodePNG error values can be retrieved with the function -LodePNG_error_text: given the numerical error code, it returns a description +lodepng_error_text: given the numerical error code, it returns a description of the error in English as a string. -Check the implementation of LodePNG_error_text to see the meaning of each error code. +Check the implementation of lodepng_error_text to see the meaning of each code. 8. chunks and PNG editing ------------------------- If you want to add extra chunks to a PNG you encode, or use LodePNG for a PNG -editor that should follow the rules about handling of unknown chunks, or if you +editor that should follow the rules about handling of unknown chunks, or if your program is able to read other types of chunks than the ones handled by LodePNG, then that's possible with the chunk functions of LodePNG. @@ -1495,7 +1330,6 @@ A PNG chunk has the following layout: length bytes data 4 bytes CRC - 8.1. iterating through chunks ----------------------------- @@ -1506,21 +1340,21 @@ then you have a chunk, and can check the following things of it. NOTE: none of these functions check for memory buffer boundaries. To avoid exploits, always make sure the buffer contains all the data of the chunks. -When using LodePNG_chunk_next, make sure the returned value is within the +When using lodepng_chunk_next, make sure the returned value is within the allocated memory. -unsigned LodePNG_chunk_length(const unsigned char* chunk): +unsigned lodepng_chunk_length(const unsigned char* chunk): Get the length of the chunk's data. The total chunk length is this length + 12. -void LodePNG_chunk_type(char type[5], const unsigned char* chunk): -unsigned char LodePNG_chunk_type_equals(const unsigned char* chunk, const char* type): +void lodepng_chunk_type(char type[5], const unsigned char* chunk): +unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type): Get the type of the chunk or compare if it's a certain type -unsigned char LodePNG_chunk_critical(const unsigned char* chunk): -unsigned char LodePNG_chunk_private(const unsigned char* chunk): -unsigned char LodePNG_chunk_safetocopy(const unsigned char* chunk): +unsigned char lodepng_chunk_critical(const unsigned char* chunk): +unsigned char lodepng_chunk_private(const unsigned char* chunk): +unsigned char lodepng_chunk_safetocopy(const unsigned char* chunk): Check if the chunk is critical in the PNG standard (only IHDR, PLTE, IDAT and IEND are). Check if the chunk is private (public chunks are part of the standard, private ones not). @@ -1528,25 +1362,25 @@ Check if the chunk is safe to copy. If it's not, then, when modifying data in a chunk, unsafe to copy chunks of the old image may NOT be saved in the new one if your program doesn't handle that type of unknown chunk. -unsigned char* LodePNG_chunk_data(unsigned char* chunk): -const unsigned char* LodePNG_chunk_data_const(const unsigned char* chunk): +unsigned char* lodepng_chunk_data(unsigned char* chunk): +const unsigned char* lodepng_chunk_data_const(const unsigned char* chunk): Get a pointer to the start of the data of the chunk. -unsigned LodePNG_chunk_check_crc(const unsigned char* chunk): -void LodePNG_chunk_generate_crc(unsigned char* chunk): +unsigned lodepng_chunk_check_crc(const unsigned char* chunk): +void lodepng_chunk_generate_crc(unsigned char* chunk): Check if the crc is correct or generate a correct one. -unsigned char* LodePNG_chunk_next(unsigned char* chunk): -const unsigned char* LodePNG_chunk_next_const(const unsigned char* chunk): +unsigned char* lodepng_chunk_next(unsigned char* chunk): +const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk): Iterate to the next chunk. This works if you have a buffer with consecutive chunks. Note that these functions do no boundary checking of the allocated data whatsoever, so make sure there is enough data available in the buffer to be able to go to the next chunk. -unsigned LodePNG_append_chunk(unsigned char** out, size_t* outlength, const unsigned char* chunk): -unsigned LodePNG_create_chunk(unsigned char** out, size_t* outlength, unsigned length, +unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk): +unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length, const char* type, const unsigned char* data): These functions are used to create new chunks that are appended to the data in *out that has @@ -1554,37 +1388,36 @@ length *outlength. The append function appends an existing chunk to the new data function creates a new chunk with the given parameters and appends it. Type is the 4-letter name of the chunk. +8.2. chunks in info_png +----------------------- -8.2. chunks in infoPng ----------------------- - -The LodePNG_InfoPng struct contains a struct LodePNG_UnknownChunks in it. This -struct has 3 buffers (each with size) to contain 3 types of unknown chunks: +The LodePNGInfo struct contains fields with the unknown chunk in it. It has 3 +buffers (each with size) to contain 3 types of unknown chunks: the ones that come before the PLTE chunk, the ones that come between the PLTE and the IDAT chunks, and the ones that come after the IDAT chunks. It's necessary to make the distionction between these 3 cases because the PNG standard forces to keep the ordering of unknown chunks compared to the critical chunks, but does not force any other ordering rules. -infoPng.unknown_chunks.data[0] is the chunks before PLTE -infoPng.unknown_chunks.data[1] is the chunks after PLTE, before IDAT -infoPng.unknown_chunks.data[2] is the chunks after IDAT +info_png.unknown_chunks_data[0] is the chunks before PLTE +info_png.unknown_chunks_data[1] is the chunks after PLTE, before IDAT +info_png.unknown_chunks_data[2] is the chunks after IDAT The chunks in these 3 buffers can be iterated through and read by using the same way described in the previous subchapter. When using the decoder to decode a PNG, you can make it store all unknown chunks -if you set the option settings.rememberUnknownChunks to 1. By default, this option -is off and is 0. +if you set the option settings.remember_unknown_chunks to 1. By default, this +option is off (0). -The encoder will always encode unknown chunks that are stored in the infoPng. If -you need it to add a particular chunk that isn't known by LodePNG, you can use -LodePNG_append_chunk or LodePNG_create_chunk to the chunk data in -infoPng.unknown_chunks.data[x]. +The encoder will always encode unknown chunks that are stored in the info_png. +If you need it to add a particular chunk that isn't known by LodePNG, you can +use lodepng_chunk_append or lodepng_chunk_create to the chunk data in +info_png.unknown_chunks_data[x]. Chunks that are known by LodePNG should not be added in that way. E.g. to make LodePNG add a bKGD chunk, set background_defined to true and add the correct -parameters there and LodePNG will generate the chunk. +parameters there instead. 9. compiler support @@ -1595,12 +1428,12 @@ LodePNG. For the C++ version, only the standard C++ library is needed on top. Add the files lodepng.c(pp) and lodepng.h to your project, include lodepng.h where needed, and your program can read/write PNG files. -Use optimization! For both the encoder and decoder, compiling with the best -optimizations makes a large difference. +If performance is important, use optimization when compiling! For both the +encoder and decoder, this makes a large difference. Make sure that LodePNG is compiled with the same compiler of the same version and with the same settings as the rest of the program, or the interfaces with -std::vectors and std::strings in C++ can be incompatible resulting in bad things. +std::vectors and std::strings in C++ can be incompatible. CHAR_BITS must be 8 or higher, because LodePNG uses unsigned chars for octets. @@ -1608,27 +1441,34 @@ CHAR_BITS must be 8 or higher, because LodePNG uses unsigned chars for octets. LodePNG is developed in gcc so this compiler is natively supported. It gives no warnings with compiler options "-Wall -Wextra -pedantic -ansi", with gcc and g++ -version 4.5.1 on Linux. +version 4.7.1 on Linux, 32-bit and 64-bit. -*) Mingw and Bloodshed DevC++ +*) Mingw -The Mingw compiler (a port of gcc) used by Bloodshed DevC++ for Windows is fully -supported by LodePNG. +The Mingw compiler (a port of gcc) for Windows is fully supported by LodePNG. -*) Visual Studio 2005 and Visual C++ 2005 Express Edition +*) Visual Studio 2005 and up, Visual C++ Express Edition 2005 and up -Versions 20070604 up to 20080107 have been tested on VS2005 and work. Visual -studio may give warnings about 'fopen' being deprecated. A multiplatform library -can't support the proposed Visual Studio alternative however. +Visual Studio may give warnings about 'fopen' being deprecated. A multiplatform library +can't support the proposed Visual Studio alternative however, so LodePNG keeps using +fopen. If you don't want to see the deprecated warnings, put this on top of lodepng.h +before the inclusions: +#define _CRT_SECURE_NO_DEPRECATE -If you're using LodePNG in VS2005 and don't want to see the deprecated warnings, -put this on top of lodepng.h before the inclusions: #define _CRT_SECURE_NO_DEPRECATE +With warning level 4 (W4), there may be a lot of warnings about possible loss of data +due to integer conversions. I'm not planning to resolve these warnings. The gcc compiler +doesn't give those even with strict warning flags. With warning level 3 in VS 2008 +Express Edition, LodePNG is, other than the fopen warnings, warning-free again since +version 20120923. + +Visual Studio may want "stdafx.h" files to be included in each source file. That +is not standard C++ and will not be added to the stock LodePNG. Try to find a +setting to disable it for this source file. *) Visual Studio 6.0 -The C++ version of LodePNG was not supported by Visual Studio 6.0 because Visual -Studio 6.0 doesn't follow the C++ standard and implements it incorrectly. -The current C version of LodePNG has not been tested in VS6 but may work now. +LodePNG support for Visual Studio 6.0 is not guaranteed because VS6 doesn't +follow the C++ standard correctly. *) Comeau C/C++ @@ -1642,51 +1482,22 @@ for C and C++. *) Other Compilers -If you encounter problems on other compilers, I'm happy to help out make LodePNG -support the compiler if it supports the ISO C90 and C++ standard well enough and -the required modification doesn't require using non standard or less good C/C++ -code or headers. +If you encounter problems on other compilers, feel free to let me know and I may +try to fix it if the compiler is modern standards complient. 10. examples ------------ -This decoder and encoder example show the most basic usage of LodePNG (using the -classes, not the simple functions, which would be trivial) - -More complex examples can be found in: --lodepng_examples.c: 9 different examples in C, such as showing the image with SDL, ... --lodepng_examples.cpp: the same examples in C++ using the C++ wrapper of LodePNG - -These files can be found on the LodePNG website or searched for on the internet. +This decoder example shows the most basic usage of LodePNG. More complex +examples can be found on the LodePNG website. 10.1. decoder C++ example ------------------------- -//////////////////////////////////////////////////////////////////////////////// #include "lodepng.h" #include -int main(int argc, char *argv[]) -{ - const char* filename = argc > 1 ? argv[1] : "test.png"; - - //load and decode - std::vector buffer, image; //buffer will contain the PNG file, image will contain the raw pixels - LodePNG::loadFile(buffer, filename); //load the image file with given filename - LodePNG::Decoder decoder; - decoder.decode(image, buffer.size() ? &buffer[0] : 0, (unsigned)buffer.size()); //decode the png - - //if there's an error, display it - if(decoder.hasError()) - std::cout << "error " << decoder.getError() << ": "<< LodePNG_error_text(decoder.getError()) << std::endl; - - int width = decoder.getWidth(); //get the width in pixels - int height = decoder.getHeight(); //get the height in pixels - //the pixels are now in the vector "image", 4 bytes per pixel, ordered RGBARGBA..., use it as texture, draw it, ... -} - -//alternative version using the "simple" function int main(int argc, char *argv[]) { const char* filename = argc > 1 ? argv[1] : "test.png"; @@ -1694,62 +1505,17 @@ int main(int argc, char *argv[]) //load and decode std::vector image; unsigned width, height; - unsigned error = LodePNG::decode(image, width, height, filename); + unsigned error = lodepng::decode(image, width, height, filename); //if there's an error, display it - if(error != 0) std::cout << "error " << error << ": " << LodePNG_error_text(error) << std::endl; + if(error) std::cout << "decoder error " << error << ": " << lodepng_error_text(error) << std::endl; //the pixels are now in the vector "image", 4 bytes per pixel, ordered RGBARGBA..., use it as texture, draw it, ... } -//////////////////////////////////////////////////////////////////////////////// - -10.2. encoder C++ example -------------------------- - -//////////////////////////////////////////////////////////////////////////////// -#include "lodepng.h" -#include - -//saves image to filename given as argument. Warning, this overwrites the file without warning! -int main(int argc, char *argv[]) -{ - //check if user gave a filename - if(argc <= 1) - { - std::cout << "please provide a filename to save to\n"; - return 0; - } - - //generate some image - std::vector image; - image.resize(512 * 512 * 4); - for(unsigned y = 0; y < 512; y++) - for(unsigned x = 0; x < 512; x++) - { - image[4 * 512 * y + 4 * x + 0] = 255 * !(x & y); - image[4 * 512 * y + 4 * x + 1] = x ^ y; - image[4 * 512 * y + 4 * x + 2] = x | y; - image[4 * 512 * y + 4 * x + 3] = 255; - } - - //encode and save, using the Encoder class - std::vector buffer; - LodePNG::Encoder encoder; - encoder.encode(buffer, image, 512, 512); - LodePNG::saveFile(buffer, argv[1]); - - //the same as the 4 lines of code above, but in 1 call without the class: - //LodePNG::encode(argv[1], image, 512, 512); -} -//////////////////////////////////////////////////////////////////////////////// - - -10.3. Decoder C example +10.2. decoder C example ----------------------- -This example loads the PNG from a file into a pixel buffer in 1 function call - #include "lodepng.h" int main(int argc, char *argv[]) @@ -1757,16 +1523,16 @@ int main(int argc, char *argv[]) unsigned error; unsigned char* image; size_t width, height; + const char* filename = argc > 1 ? argv[1] : "test.png"; - if(argc <= 1) return 0; + error = lodepng_decode32_file(&image, &width, &height, filename); - error = LodePNG_decode32_file(&image, &width, &height, filename); + if(error) printf("decoder error %u: %s\n", error, lodepng_error_text(error)); - if(error != 0) printf("error %u: %s\n", error, LodePNG_error_text(error)); - - //use image here + / * use image here * / free(image); + return 0; } @@ -1779,6 +1545,25 @@ yyyymmdd. Some changes aren't backwards compatible. Those are indicated with a (!) symbol. +*) 28 jan 2013: Bugfix with color key. +*) 27 okt 2012: Tweaks in text chunk keyword length error handling. +*) 8 okt 2012 (!): Added new filter strategy (entropy) and new auto color mode. + (no palette). Better deflate tree encoding. New compression tweak settings. + Faster color conversions while decoding. Some internal cleanups. +*) 23 sep 2012: Reduced warnings in Visual Studio a little bit. +*) 1 sep 2012 (!): Removed #define's for giving custom (de)compression functions + and made it work with function pointers instead. +*) 23 jun 2012: Added more filter strategies. Made it easier to use custom alloc + and free functions and toggle #defines from compiler flags. Small fixes. +*) 6 may 2012 (!): Made plugging in custom zlib/deflate functions more flexible. +*) 22 apr 2012 (!): Made interface more consistent, renaming a lot. Removed + redundant C++ codec classes. Reduced amount of structs. Everything changed, + but it is cleaner now imho and functionality remains the same. Also fixed + several bugs and shrinked the implementation code. Made new samples. +*) 6 nov 2011 (!): By default, the encoder now automatically chooses the best + PNG color model and bit depth, based on the amount and type of colors of the + raw image. For this, autoLeaveOutAlphaChannel replaced by auto_choose_color. +*) 9 okt 2011: simpler hash chain implementation for the encoder. *) 8 sep 2011: lz77 encoder lazy matching instead of greedy matching. *) 23 aug 2011: tweaked the zlib compression parameters after benchmarking. A bug with the PNG filtertype heuristic was fixed, so that it chooses much @@ -1833,7 +1618,7 @@ symbol. *) 11 mar 2007: very simple addition: ability to encode bKGD chunks. *) 04 mar 2007: (!) tEXt chunk related fixes, and support for encoding palettized PNG images. Plus little interface change with palette and texts. -*) 03 mar 2007: Made it encode dynamic Huffman shorter with repeat codes. +*) 03 mar 2007: Made it encode dynamic Huffman shorter with repeat codes. Fixed a bug where the end code of a block had length 0 in the Huffman tree. *) 26 feb 2007: Huffman compression with dynamic trees (BTYPE 2) now implemented and supported by the encoder, resulting in smaller PNGs at the output. @@ -1892,8 +1677,5 @@ Domain: gmail dot com. Account: lode dot vandevenne. -Copyright (c) 2005-2011 Lode Vandevenne +Copyright (c) 2005-2012 Lode Vandevenne */ - -#endif -