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Diffstat (limited to 'tests/lodepng.cpp')
| -rw-r--r-- | tests/lodepng.cpp | 5797 |
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diff --git a/tests/lodepng.cpp b/tests/lodepng.cpp deleted file mode 100644 index 831194f..0000000 --- a/tests/lodepng.cpp +++ /dev/null @@ -1,5797 +0,0 @@ -/* -LodePNG version 20110908 - -Copyright (c) 2005-2011 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 -arising from the use of this software. - -Permission is granted to anyone to use this software for any purpose, -including commercial applications, and to alter it and redistribute it -freely, subject to the following restrictions: - - 1. The origin of this software must not be misrepresented; you must not - claim that you wrote the original software. If you use this software - in a product, an acknowledgment in the product documentation would be - appreciated but is not required. - - 2. Altered source versions must be plainly marked as such, and must not be - misrepresented as being the original software. - - 3. This notice may not be removed or altered from any source - distribution. -*/ - -/* -The manual and changelog are in the header file "lodepng.h" -Rename this file to lodepng.cpp to use it for C++, or to lodepng.c to use it for C. -*/ - -#include "lodepng.h" - -#include <stdio.h> -#include <stdlib.h> - -#ifdef __cplusplus -#include <fstream> -#endif /*__cplusplus*/ - -#define VERSION_STRING "20110908" - -/* -This source file is built up in the following large parts. The code sections -with the "LODEPNG_COMPILE_" #defines divide this up further in an intermixed way. --Tools for C and common code for PNG and Zlib --C Code for Zlib (huffman, deflate, ...) --C Code for PNG (file format chunks, adam7, PNG filters, color conversions, ...) --The C++ wrapper around all of the above -*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* // Tools for C, and common code for PNG and Zlib. // */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ - -/* -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); -*/ -#define CERROR_BREAK(errorvar, code)\ -{\ - errorvar = code;\ - break;\ -} - -/*version of CERROR_BREAK that assumes the common case where the error variable is named "error"*/ -#define ERROR_BREAK(code) CERROR_BREAK(error, code) - -/* -About vector, 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. --They're not used in the interface, only internally in this file as static functions. --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 -{ - unsigned* data; - size_t size; /*size in number of unsigned longs*/ - size_t allocsize; /*allocated size in bytes*/ -} uivector; - -static void uivector_cleanup(void* p) -{ - ((uivector*)p)->size = ((uivector*)p)->allocsize = 0; - free(((uivector*)p)->data); - ((uivector*)p)->data = NULL; -} - -/*returns 1 if success, 0 if failure ==> nothing done*/ -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); - if(data) - { - p->allocsize = newsize; - p->data = (unsigned*)data; - p->size = size; - } - else return 0; - } - else p->size = size; - return 1; -} - -/*resize and give all new elements the value*/ -static unsigned uivector_resizev(uivector* p, size_t size, unsigned value) -{ - size_t oldsize = p->size, i; - if(!uivector_resize(p, size)) return 0; - for(i = oldsize; i < size; i++) p->data[i] = value; - return 1; -} - -static void uivector_init(uivector* p) -{ - p->data = NULL; - p->size = p->allocsize = 0; -} - -#ifdef LODEPNG_COMPILE_ENCODER -/*returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned uivector_push_back(uivector* p, unsigned c) -{ - if(!uivector_resize(p, p->size + 1)) return 0; - p->data[p->size - 1] = c; - return 1; -} - -/*copy q to p, returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned uivector_copy(uivector* p, const uivector* q) -{ - size_t i; - if(!uivector_resize(p, q->size)) return 0; - for(i = 0; i < q->size; i++) p->data[i] = q->data[i]; - return 1; -} - -static void uivector_swap(uivector* p, uivector* q) -{ - size_t tmp; - unsigned* 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; -} -#endif /*LODEPNG_COMPILE_ENCODER*/ -#endif /*LODEPNG_COMPILE_ZLIB*/ - -/* /////////////////////////////////////////////////////////////////////////// */ - -/*dynamic vector of unsigned chars*/ -typedef struct ucvector -{ - unsigned char* data; - size_t size; /*used size*/ - 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); - if(data) - { - p->allocsize = newsize; - p->data = (unsigned char*)data; - p->size = size; - } - else return 0; /*error: not enough memory*/ - } - else p->size = size; - return 1; -} - -#ifdef LODEPNG_COMPILE_DECODER -#ifdef LODEPNG_COMPILE_PNG -/*resize and give all new elements the value*/ -static unsigned ucvector_resizev(ucvector* p, size_t size, unsigned char value) -{ - size_t oldsize = p->size, i; - if(!ucvector_resize(p, size)) return 0; - 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; -} - -#ifdef LODEPNG_COMPILE_ZLIB -/*you can both convert from vector to buffer&size and vica versa. If you use -init_buffer to take over a buffer and size, it is not needed to use cleanup*/ -static void ucvector_init_buffer(ucvector* p, unsigned char* buffer, size_t size) -{ - p->data = buffer; - p->allocsize = p->size = size; -} -#endif /*LODEPNG_COMPILE_ZLIB*/ - -#ifdef LODEPNG_COMPILE_ENCODER -/*returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned ucvector_push_back(ucvector* p, unsigned char c) -{ - if(!ucvector_resize(p, p->size + 1)) return 0; - p->data[p->size - 1] = c; - return 1; -} -#endif /*LODEPNG_COMPILE_ENCODER*/ - - -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_PNG -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS -/*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); - if(data) - { - data[size] = 0; /*null termination char*/ - *out = data; - } - return data != 0; -} - -/*init a {char*, size_t} pair for use as string*/ -static void string_init(char** out) -{ - *out = NULL; - string_resize(out, 0); -} - -/*free the above pair again*/ -static void string_cleanup(char** out) -{ - free(*out); - *out = NULL; -} - -static void string_set(char** out, const char* in) -{ - size_t insize = strlen(in), i = 0; - if(string_resize(out, insize)) - { - for(i = 0; i < insize; i++) - { - (*out)[i] = in[i]; - } - } -} -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -#endif /*LODEPNG_COMPILE_PNG*/ - -/* ////////////////////////////////////////////////////////////////////////// */ - -unsigned LodePNG_read32bitInt(const unsigned char* buffer) -{ - return (buffer[0] << 24) | (buffer[1] << 16) | (buffer[2] << 8) | buffer[3]; -} - -/*buffer must have at least 4 allocated bytes available*/ -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); -} - -#ifdef LODEPNG_COMPILE_ENCODER -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); -} -#endif /*LODEPNG_COMPILE_ENCODER*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / File IO / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_DISK - -unsigned LodePNG_loadFile(unsigned char** out, size_t* outsize, const char* filename) -{ - FILE* file; - long size; - - /*provide some proper output values if error will happen*/ - *out = 0; - *outsize = 0; - - file = fopen(filename, "rb"); - if(!file) return 78; - - /*get filesize:*/ - fseek(file , 0 , SEEK_END); - size = ftell(file); - rewind(file); - - /*read contents of the file into the vector*/ - *outsize = 0; - *out = (unsigned char*)malloc((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*/ - 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) -{ - FILE* file; - file = fopen(filename, "wb" ); - if(!file) return 79; - fwrite((char*)buffer , 1 , buffersize, file); - fclose(file); - return 0; -} - -#endif /*LODEPNG_COMPILE_DISK*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* // End of common code and tools. Begin of Zlib related code. // */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ - -#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) -{ - /*add a new byte at the end*/ - if((*bitpointer) % 8 == 0) ucvector_push_back(bitstream, (unsigned char)0); - /*earlier bit of huffman code is in a lesser significant bit of an earlier byte*/ - (bitstream->data[bitstream->size - 1]) |= (bit << ((*bitpointer) & 0x7)); - (*bitpointer)++; -} - -static void addBitsToStream(size_t* bitpointer, ucvector* bitstream, unsigned value, size_t nbits) -{ - size_t i; - for(i = 0; i < nbits; i++) addBitToStream(bitpointer, bitstream, (unsigned char)((value >> i) & 1)); -} - -static void addBitsToStreamReversed(size_t* bitpointer, ucvector* bitstream, unsigned value, size_t nbits) -{ - size_t i; - for(i = 0; i < nbits; i++) addBitToStream(bitpointer, bitstream, (unsigned char)((value >> (nbits - 1 - i)) & 1)); -} -#endif /*LODEPNG_COMPILE_ENCODER*/ - -#ifdef LODEPNG_COMPILE_DECODER - -#define READBIT(bitpointer, bitstream) ((bitstream[bitpointer >> 3] >> (bitpointer & 0x7)) & (unsigned char)1) - -static unsigned char readBitFromStream(size_t* bitpointer, const unsigned char* bitstream) -{ - unsigned char result = (unsigned char)(READBIT(*bitpointer, bitstream)); - (*bitpointer)++; - return result; -} - -static unsigned readBitsFromStream(size_t* bitpointer, const unsigned char* bitstream, size_t nbits) -{ - unsigned result = 0, i; - for(i = 0; i < nbits; i++) - { - result += ((unsigned)READBIT(*bitpointer, bitstream)) << i; - (*bitpointer)++; - } - return result; -} -#endif /*LODEPNG_COMPILE_DECODER*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Deflate - Huffman / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -#define FIRST_LENGTH_CODE_INDEX 257 -#define LAST_LENGTH_CODE_INDEX 285 -/*256 literals, the end code, some length codes, and 2 unused codes*/ -#define NUM_DEFLATE_CODE_SYMBOLS 288 -/*the distance codes have their own symbols, 30 used, 2 unused*/ -#define NUM_DISTANCE_SYMBOLS 32 -/*the code length codes. 0-15: code lengths, 16: copy previous 3-6 times, 17: 3-10 zeros, 18: 11-138 zeros*/ -#define NUM_CODE_LENGTH_CODES 19 - -/*the base lengths represented by codes 257-285*/ -static const unsigned LENGTHBASE[29] - = {3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 35, 43, 51, 59, - 67, 83, 99, 115, 131, 163, 195, 227, 258}; - -/*the extra bits used by codes 257-285 (added to base length)*/ -static const unsigned LENGTHEXTRA[29] - = {0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, - 4, 4, 4, 4, 5, 5, 5, 5, 0}; - -/*the base backwards distances (the bits of distance codes appear after length codes and use their own huffman tree)*/ -static const unsigned DISTANCEBASE[30] - = {1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385, 513, - 769, 1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577}; - -/*the extra bits of backwards distances (added to base)*/ -static const unsigned DISTANCEEXTRA[30] - = {0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, - 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13}; - -/*the order in which "code length alphabet code lengths" are stored, out of this -the huffman tree of the dynamic huffman tree lengths is generated*/ -static const unsigned CLCL_ORDER[NUM_CODE_LENGTH_CODES] - = {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; - -/* ////////////////////////////////////////////////////////////////////////// */ - -/* -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 maxbitlen; /*maximum number of bits a single code can get*/ - unsigned numcodes; /*number of symbols in the alphabet = number of codes*/ -} HuffmanTree; - -/*function used for debug purposes to draw the tree in ascii art with C++*/ -/*#include <iostream> -static void HuffmanTree_draw(HuffmanTree* tree) -{ - std::cout << "tree. length: " << tree->numcodes << " maxbitlen: " << tree->maxbitlen << std::endl; - for(size_t i = 0; i < tree->tree1d.size; i++) - { - if(tree->lengths.data[i]) - std::cout << i << " " << tree->tree1d.data[i] << " " << tree->lengths.data[i] << std::endl; - } - std::cout << std::endl; -}*/ - -static void HuffmanTree_init(HuffmanTree* tree) -{ - uivector_init(&tree->tree2d); - uivector_init(&tree->tree1d); - uivector_init(&tree->lengths); -} - -static void HuffmanTree_cleanup(HuffmanTree* tree) -{ - uivector_cleanup(&tree->tree2d); - uivector_cleanup(&tree->tree1d); - uivector_cleanup(&tree->lengths); -} - -/*the tree representation used by the decoder. return value is error*/ -static unsigned HuffmanTree_make2DTree(HuffmanTree* tree) -{ - unsigned nodefilled = 0; /*up to which node it is filled*/ - 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*/ - - /* - convert tree1d[] to tree2d[][]. In the 2D array, a value of 32767 means - uninited, a value >= numcodes is an address to another bit, a value < numcodes - is a code. The 2 rows are the 2 possible bit values (0 or 1), there are as - many columns as codes - 1. - A good huffmann tree has N * 2 - 1 nodes, of which N - 1 are internal nodes. - Here, the internal nodes are stored (what their 0 and 1 option point to). - 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++) - { - tree->tree2d.data[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*/ - { - 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*/ - { - if(i + 1 == tree->lengths.data[n]) /*last bit*/ - { - tree->tree2d.data[2 * treepos + bit] = n; /*put the current code in it*/ - treepos = 0; - } - else - { - /*put address of the next step in here, first that address has to be found of course - (it's just nodefilled + 1)...*/ - nodefilled++; - /*addresses encoded with numcodes added to it*/ - tree->tree2d.data[2 * treepos + bit] = nodefilled + tree->numcodes; - treepos = nodefilled; - } - } - else treepos = tree->tree2d.data[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*/ - } - - return 0; -} - -/* -Second step for the ...makeFromLengths and ...makeFromFrequencies functions. -numcodes, lengths and maxbitlen must already be filled in correctly. return -value is error. -*/ -static unsigned HuffmanTree_makeFromLengths2(HuffmanTree* tree) -{ - uivector blcount; - uivector nextcode; - unsigned bits, n, error = 0; - - uivector_init(&blcount); - uivector_init(&nextcode); - if(!uivector_resize(&tree->tree1d, tree->numcodes) - || !uivector_resizev(&blcount, tree->maxbitlen + 1, 0) - || !uivector_resizev(&nextcode, tree->maxbitlen + 1, 0)) - error = 9902; /*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]]++; - /*step 2: generate the nextcode values*/ - for(bits = 1; bits <= tree->maxbitlen; bits++) - { - nextcode.data[bits] = (nextcode.data[bits - 1] + blcount.data[bits - 1]) << 1; - } - /*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]]++; - } - } - - uivector_cleanup(&blcount); - uivector_cleanup(&nextcode); - - if(!error) return HuffmanTree_make2DTree(tree); - else return error; -} - -/* -given the code lengths (as stored in the PNG file), generate the tree as defined -by Deflate. maxbitlen is the maximum bits that a code in the tree can have. -return value is error. -*/ -static unsigned HuffmanTree_makeFromLengths(HuffmanTree* tree, const unsigned* bitlen, - 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->numcodes = (unsigned)numcodes; /*number of symbols*/ - tree->maxbitlen = maxbitlen; - return HuffmanTree_makeFromLengths2(tree); -} - -#ifdef LODEPNG_COMPILE_ENCODER - -/* -A coin, this is the terminology used for the package-merge algorithm and the -coin collector's problem. This is used to generate the huffman tree. -A coin can be multiple coins (when they're merged) -*/ -typedef struct Coin -{ - uivector symbols; - float weight; /*the sum of all weights in this coin*/ -} Coin; - -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) -{ - uivector_cleanup(&((Coin*)c)->symbols); -} - -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) -{ - size_t i; - for(i = 0; i < c2->symbols.size; i++) uivector_push_back(&c1->symbols, c2->symbols.data[i]); - c1->weight += c2->weight; -} - -/* -Coin_sort: 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) -{ - size_t gap = amount; - unsigned char swapped = 0; - while((gap > 1) || swapped) - { - size_t i; - gap = (gap * 10) / 13; /*shrink factor 1.3*/ - if(gap == 9 || gap == 10) gap = 11; /*combsort11*/ - if(gap < 1) gap = 1; - swapped = 0; - for(i = 0; i < amount - gap; i++) - { - size_t j = i + gap; - if(data[j].weight < data[i].weight) - { - float temp = data[j].weight; data[j].weight = data[i].weight; data[i].weight = temp; - uivector_swap(&data[i].symbols, &data[j].symbols); - swapped = 1; - } - } - } -} - -static unsigned HuffmanTree_fillInCoins(vector* coins, const unsigned* frequencies, unsigned numcodes, size_t sum) -{ - unsigned i; - 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)) - { - vector_cleanup(coins); - return 9904; /*alloc fail*/ - } - 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 i, j; - size_t sum = 0, numpresent = 0; - unsigned error = 0; - - vector prev_row; /*type Coin, the previous row of coins*/ - vector coins; /*type Coin, the coins of the currently calculated row*/ - - tree->maxbitlen = maxbitlen; - - for(i = 0; i < numcodes; i++) - { - if(frequencies[i] > 0) - { - numpresent++; - sum += frequencies[i]; - } - } - - 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*/ - - /*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) */ - if(numpresent == 0) - { - tree->lengths.data[0] = 1; - return HuffmanTree_makeFromLengths2(tree); - } - /*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*/ - { - 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(!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); - } - } - } - - if(!error) - { - /*keep the coins with lowest weight, so that they add up to the amount of symbols - 1*/ - vector_resized(&coins, numpresent - 1, Coin_cleanup); - - /*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++) - { - Coin* coin = (Coin*)vector_get(&coins, i); - for(j = 0; j < coin->symbols.size; j++) tree->lengths.data[coin->symbols.data[j]]++; - } - - error = HuffmanTree_makeFromLengths2(tree); - } - - vector_cleanupd(&coins, Coin_cleanup); - vector_cleanupd(&prev_row, Coin_cleanup); - - return error; -} - -static unsigned HuffmanTree_getCode(const HuffmanTree* tree, unsigned index) -{ - return tree->tree1d.data[index]; -} - -static unsigned HuffmanTree_getLength(const HuffmanTree* tree, unsigned index) -{ - return tree->lengths.data[index]; -} -#endif /*LODEPNG_COMPILE_ENCODER*/ - -/*get the literal and length code tree of a deflated block with fixed tree, as per the deflate specification*/ -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*/ - - 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; - - error = HuffmanTree_makeFromLengths(tree, bitlen.data, NUM_DEFLATE_CODE_SYMBOLS, 15); - } - - uivector_cleanup(&bitlen); - return error; -} - -/*get the distance code tree of a deflated block with fixed tree, as specified in the deflate specification*/ -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*/ - - /*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); - return error; -} - -#ifdef LODEPNG_COMPILE_DECODER - -/* -returns the code, or (unsigned)(-1) if error happened -inbitlength is the length of the complete buffer, in bits (so its byte length times 8) -*/ -static unsigned huffmanDecodeSymbol(const unsigned char* in, size_t* bp, - const HuffmanTree* codetree, size_t inbitlength) -{ - unsigned treepos = 0, ct; - for(;;) - { - 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)]; - (*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*/ - - if(treepos >= codetree->numcodes) return (unsigned)(-1); /*error: it appeared outside the codetree*/ - } -} -#endif /*LODEPNG_COMPILE_DECODER*/ - -#ifdef LODEPNG_COMPILE_DECODER - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Inflator (Decompressor) / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -/*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...*/ - generateFixedLitLenTree(tree_ll); - generateFixedDistanceTree(tree_d); -} - -/*get the tree of a deflated block with dynamic tree, the tree itself is also Huffman compressed with a known tree*/ -static unsigned getTreeInflateDynamic(HuffmanTree* tree_ll, HuffmanTree* tree_d, - const unsigned char* in, size_t* bp, size_t inlength) -{ - /*make sure that length values that aren't filled in will be 0, or a wrong tree will be generated*/ - unsigned error = 0; - unsigned n, HLIT, HDIST, HCLEN, i; - 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*/ - /*code length code lengths ("clcl"), the bit lengths of the huffman tree used to compress bitlen_ll and bitlen_d*/ - uivector bitlen_cl; - 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*/ - - /*number of literal/length codes + 257. Unlike the spec, the value 257 is added to it here already*/ - HLIT = readBitsFromStream(bp, in, 5) + 257; - /*number of distance codes. Unlike the spec, the value 1 is added to it here already*/ - HDIST = readBitsFromStream(bp, in, 5) + 1; - /*number of code length codes. Unlike the spec, the value 4 is added to it here already*/ - 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); - - 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*/ - } - - error = HuffmanTree_makeFromLengths(&tree_cl, bitlen_cl.data, bitlen_cl.size, 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*/ - - /*i is the current symbol we're reading in the part that contains the code lengths of lit/len and dist codes*/ - 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; - i++; - } - else if(code == 16) /*repeat previous*/ - { - 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*/ - - replength += readBitsFromStream(bp, in, 2); - - if((i - 1) < HLIT) value = bitlen_ll.data[i - 1]; - else value = bitlen_d.data[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; - 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*/ - - replength += readBitsFromStream(bp, in, 3); - - /*repeat this value in the next lengths*/ - for(n = 0; n < replength; n++) - { - 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; - 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*/ - - replength += readBitsFromStream(bp, in, 7); - - /*repeat this value in the next lengths*/ - for(n = 0; n < replength; n++) - { - 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; - i++; - } - } - else /*if(code == (unsigned)(-1))*/ /*huffmanDecodeSymbol returns (unsigned)(-1) in case of error*/ - { - if(code == (unsigned)(-1)) - { - /*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; - } - else error = 16; /*unexisting code, this can never happen*/ - break; - } - } - if(error) break; - - if(bitlen_ll.data[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); - if(error) break; - error = HuffmanTree_makeFromLengths(tree_d, &bitlen_d.data[0], bitlen_d.size, 15); - - break; /*end of error-while*/ - } - - uivector_cleanup(&bitlen_cl); - uivector_cleanup(&bitlen_ll); - uivector_cleanup(&bitlen_d); - HuffmanTree_cleanup(&tree_cl); - - return error; -} - -/*inflate a block with dynamic of fixed Huffman tree*/ -static unsigned inflateHuffmanBlock(ucvector* out, const unsigned char* in, size_t* bp, - size_t* pos, size_t inlength, unsigned btype) -{ - unsigned error = 0; - HuffmanTree tree_ll; /*the huffman tree for literal and length codes*/ - HuffmanTree tree_d; /*the huffman tree for distance codes*/ - size_t inbitlength = inlength * 8; - - HuffmanTree_init(&tree_ll); - 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); - } - - for(;;) /*decode all symbols until end reached*/ - { - /*code_ll is literal, length or end code*/ - unsigned code_ll = huffmanDecodeSymbol(in, bp, &tree_ll, inbitlength); - if(code_ll <= 255) /*literal symbol*/ - { - if((*pos) >= out->size) - { - /*reserve more room at once*/ - if(!ucvector_resize(out, ((*pos) + 1) * 2)) ERROR_BREAK(9913 /*alloc fail*/); - } - out->data[(*pos)] = (unsigned char)(code_ll); - (*pos)++; - } - else if(code_ll >= FIRST_LENGTH_CODE_INDEX && code_ll <= LAST_LENGTH_CODE_INDEX) /*length code*/ - { - 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*/ - length += readBitsFromStream(bp, in, numextrabits_l); - - /*part 3: get distance code*/ - code_d = huffmanDecodeSymbol(in, bp, &tree_d, inbitlength); - if(code_d > 29) - { - if(code_ll == (unsigned)(-1)) /*huffmanDecodeSymbol returns (unsigned)(-1) in case of error*/ - { - /*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; - } - else error = 18; /*error: invalid distance code (30-31 are never used)*/ - break; - } - distance = DISTANCEBASE[code_d]; - - /*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*/ - - distance += readBitsFromStream(bp, in, numextrabits_d); - - /*part 5: fill in all the out[n] values based on the length and dist*/ - start = (*pos); - 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*/); - } - - for(forward = 0; forward < length; forward++) - { - out->data[(*pos)] = out->data[backward]; - (*pos)++; - backward++; - if(backward >= start) backward = start - distance; - } - } - else if(code_ll == 256) - { - break; /*end code, break the loop*/ - } - else /*if(code == (unsigned)(-1))*/ /*huffmanDecodeSymbol returns (unsigned)(-1) in case of error*/ - { - /*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; - break; - } - } - - HuffmanTree_cleanup(&tree_ll); - HuffmanTree_cleanup(&tree_d); - - return error; -} - -static unsigned inflateNoCompression(ucvector* out, const unsigned char* in, size_t* bp, size_t* pos, size_t inlength) -{ - /*go to first boundary of byte*/ - size_t p; - unsigned LEN, NLEN, n, error = 0; - while(((*bp) & 0x7) != 0) (*bp)++; - p = (*bp) / 8; /*byte position*/ - - /*read LEN (2 bytes) and NLEN (2 bytes)*/ - if(p >= inlength - 4) return 52; /*error, bit pointer will jump past memory*/ - LEN = in[p] + 256 * in[p + 1]; p += 2; - NLEN = in[p] + 256 * in[p + 1]; p += 2; - - /*check if 16-bit NLEN is really the one's complement of LEN*/ - if(LEN + NLEN != 65535) return 21; /*error: NLEN is not one's complement of LEN*/ - - if((*pos) + LEN >= out->size) - { - if(!ucvector_resize(out, (*pos) + LEN)) return 9915; /*alloc fail*/ - } - - /*read the literal data: LEN bytes are now stored in the out buffer*/ - if(p + LEN > inlength) return 23; /*error: reading outside of in buffer*/ - for(n = 0; n < LEN; n++) out->data[(*pos)++] = in[p++]; - - (*bp) = p * 8; - - 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) -{ - /*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; - unsigned BFINAL = 0; - size_t pos = 0; /*byte position in the out buffer*/ - - unsigned error = 0; - - 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]); - - 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*/ - - 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*/ - - return error; -} - -#endif /*LODEPNG_COMPILE_DECODER*/ - -#ifdef LODEPNG_COMPILE_ENCODER - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Deflator (Compressor) / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -static const size_t MAX_SUPPORTED_DEFLATE_LENGTH = 258; - -/*bitlen is the size in bits of the code*/ -static void addHuffmanSymbol(size_t* bp, ucvector* compressed, unsigned code, unsigned bitlen) -{ - addBitsToStreamReversed(bp, compressed, code, bitlen); -} - -/*search the index in the array, that has the largest value smaller than or equal to the given value, -given array must be sorted (if no value is smaller, it returns the size of the given array)*/ -static size_t searchCodeIndex(const unsigned* array, size_t array_size, size_t value) -{ - /*linear search implementation*/ - /*for(size_t i = 1; i < array_size; i++) if(array[i] > value) return i - 1; - return array_size - 1;*/ - - /*binary search implementation (not that much faster) (precondition: array_size > 0)*/ - size_t left = 1; - size_t right = array_size - 1; - while(left <= right) - { - size_t mid = (left + right) / 2; - if(array[mid] <= value) left = mid + 1; /*the value to find is more to the right*/ - else if(array[mid - 1] > value) right = mid - 1; /*the value to find is more to the left*/ - else return mid - 1; - } - return array_size - 1; -} - -static void addLengthDistance(uivector* values, size_t length, size_t distance) -{ - /*values in encoded vector are those used by deflate: - 0-255: literal bytes - 256: end - 257-285: length/distance pair (length code, followed by extra length bits, distance code, extra distance bits) - 286-287: invalid*/ - - unsigned length_code = (unsigned)searchCodeIndex(LENGTHBASE, 29, length); - unsigned extra_length = (unsigned)(length - LENGTHBASE[length_code]); - unsigned dist_code = (unsigned)searchCodeIndex(DISTANCEBASE, 30, distance); - unsigned extra_distance = (unsigned)(distance - DISTANCEBASE[dist_code]); - - uivector_push_back(values, length_code + FIRST_LENGTH_CODE_INDEX); - uivector_push_back(values, extra_length); - uivector_push_back(values, dist_code); - 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_CHARACTERS = 3; -static const unsigned HASH_SHIFT = 2; -/* -The HASH_NUM_CHARACTERS value is used to make encoding faster by using longer -sequences to generate a hash value from the stream bytes. Setting it to 3 -gives exactly the same compression as the brute force method, since deflate's -run length encoding starts with lengths of 3. Setting it to higher values, -like 6, can make the encoding faster (not always though!), but will cause the -encoding to miss any length between 3 and this value, so that the compression -may be worse (but this can vary too depending on the image, sometimes it is -even a bit better instead). -The HASH_NUM_VALUES is the amount of unique possible hash values that -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) -{ - unsigned result = 0; - size_t amount, i; - if(pos >= size) return 0; - amount = num; - 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) -{ - 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; -} - -/*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) -{ - 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; -} - -/*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 -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) -{ - /**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<std::vector<unsigned> > 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 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*/ - - if(!error) - { - unsigned offset, max_offset; /*the offset represents the distance in LZ77 terminology*/ - unsigned length, tablepos; -#ifdef LAZY_MATCHING - unsigned lazy = 0; - unsigned lazylength, lazyoffset; -#endif /*LAZY_MATCHING*/ - unsigned hash, initialZeros = 0; - unsigned backpos, current_offset, t1, t2, t11, 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; - - for(pos = 0; 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*/ - - /*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) - { - 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; - } - - t1 = tablepos1.data[hash]; - t2 = tablepos2.data[hash] - 1; - if(tablepos2.data[hash] == 0) t2 = hashWindow - 1; - - 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) - { - backpos = v->data[tablepos]; - current_offset = pos - backpos; - /*test the next characters*/ - foreptr = &in[pos]; - backptr = &in[backpos]; - - 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; - } - } - -#ifdef LAZY_MATCHING - if(!lazy && length >= 3 && length < MAX_SUPPORTED_DEFLATE_LENGTH) - { - lazylength = length; - lazyoffset = offset; - lazy = 1; - continue; - } - if(lazy) - { - if(pos == 0) ERROR_BREAK(81); - lazy = 0; - if(length > lazylength + 1) - { - /*push the previous character as literal*/ - if(!uivector_push_back(out, in[pos - 1])) ERROR_BREAK(9921 /*alloc fail*/); - } - else - { - length = lazylength; - offset = lazyoffset; - pos--; - } - } -#endif /*LAZY_MATCHING*/ - - /**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*/); - } - else - { - unsigned j, local_hash; - addLengthDistance(out, length, offset); - for(j = 0; j < length - 1; j++) - { - 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) - { - 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++; - } - } - } - } /*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; -} - -/* /////////////////////////////////////////////////////////////////////////// */ - -static unsigned deflateNoCompression(ucvector* out, const unsigned char* data, size_t datasize) -{ - /*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; - unsigned datapos = 0; - for(i = 0; i < numdeflateblocks; i++) - { - unsigned BFINAL, BTYPE, LEN, NLEN; - unsigned char firstbyte; - - BFINAL = (i == numdeflateblocks - 1); - BTYPE = 0; - - firstbyte = (unsigned char)(BFINAL + ((BTYPE & 1) << 1) + ((BTYPE & 2) << 1)); - ucvector_push_back(out, firstbyte); - - LEN = 65535; - if(datasize - datapos < 65535) LEN = (unsigned)datasize - datapos; - NLEN = 65535 - LEN; - - ucvector_push_back(out, (unsigned char)(LEN % 256)); - ucvector_push_back(out, (unsigned char)(LEN / 256)); - ucvector_push_back(out, (unsigned char)(NLEN % 256)); - ucvector_push_back(out, (unsigned char)(NLEN / 256)); - - /*Decompressed data*/ - for(j = 0; j < 65535 && datapos < datasize; j++) - { - ucvector_push_back(out, data[datapos++]); - } - } - - return 0; -} - -/* -write the lz77-encoded data, which has lit, len and dist codes, to compressed stream using huffman trees. -tree_ll: the tree for lit and len codes. -tree_d: the tree for distance codes. -*/ -static void writeLZ77data(size_t* bp, ucvector* out, const uivector* lz77_encoded, - const HuffmanTree* tree_ll, const HuffmanTree* tree_d) -{ - size_t i = 0; - for(i = 0; i < lz77_encoded->size; i++) - { - unsigned val = lz77_encoded->data[i]; - addHuffmanSymbol(bp, out, HuffmanTree_getCode(tree_ll, val), HuffmanTree_getLength(tree_ll, val)); - if(val > 256) /*for a length code, 3 more things have to be added*/ - { - unsigned length_index = val - FIRST_LENGTH_CODE_INDEX; - unsigned n_length_extra_bits = LENGTHEXTRA[length_index]; - unsigned length_extra_bits = lz77_encoded->data[++i]; - - unsigned distance_code = lz77_encoded->data[++i]; - - unsigned distance_index = distance_code; - unsigned n_distance_extra_bits = DISTANCEEXTRA[distance_index]; - unsigned distance_extra_bits = lz77_encoded->data[++i]; - - addBitsToStream(bp, out, length_extra_bits, n_length_extra_bits); - addHuffmanSymbol(bp, out, HuffmanTree_getCode(tree_d, distance_code), - HuffmanTree_getLength(tree_d, distance_code)); - addBitsToStream(bp, out, distance_extra_bits, n_distance_extra_bits); - } - } -} - -/*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) -{ - unsigned error = 0; - - /* - A block is compressed as follows: The PNG data is lz77 encoded, resulting in - literal bytes and length/distance pairs. This is then huffman compressed with - two huffman trees. One huffman tree is used for the lit and len values ("ll"), - another huffman tree is used for the dist values ("d"). These two trees are - stored using their code lengths, and to compress even more these code lengths - are also run-length encoded and huffman compressed. This gives a huffman tree - 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*/ - HuffmanTree tree_d; /*tree for distance codes*/ - HuffmanTree tree_cl; /*tree for encoding the code lengths representing tree_ll and tree_d*/ - uivector frequencies_ll; /*frequency of lit,len codes*/ - uivector frequencies_d; /*frequency of dist codes*/ - uivector frequencies_cl; /*frequency of code length codes*/ - uivector bitlen_lld; /*lit,len,dist code lenghts (int bits), literally (without repeat codes).*/ - uivector bitlen_lld_e; /*bitlen_lld encoded with repeat codes (this is a rudemtary run length compression)*/ - /*bitlen_cl is the code length code lengths ("clcl"). The bit lengths of codes to represent tree_cl - (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; - - /* - 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_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*/ - size_t numcodes_ll, numcodes_d, i; - size_t bp = 0; /*the bit pointer*/ - unsigned HLIT, HDIST, HCLEN; - - uivector_init(&lz77_encoded); - HuffmanTree_init(&tree_ll); - HuffmanTree_init(&tree_d); - HuffmanTree_init(&tree_cl); - uivector_init(&frequencies_ll); - uivector_init(&frequencies_d); - uivector_init(&frequencies_cl); - uivector_init(&bitlen_lld); - 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 - allow breaking out of it to the cleanup phase on error conditions.*/ - while(!error) - { - if(settings->useLZ77) - { - error = encodeLZ77(&lz77_encoded, data, datasize, settings->windowSize); /*LZ77 encoded*/ - 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_resizev(&frequencies_ll, 286, 0)) ERROR_BREAK(9924 /*alloc fail*/); - if(!uivector_resizev(&frequencies_d, 30, 0)) ERROR_BREAK(9925 /*alloc fail*/); - - /*Count the frequencies of lit, len and dist codes*/ - for(i = 0; i < lz77_encoded.size; i++) - { - unsigned symbol = lz77_encoded.data[i]; - frequencies_ll.data[symbol]++; - if(symbol > 256) - { - unsigned dist = lz77_encoded.data[i + 2]; - frequencies_d.data[dist]++; - i += 3; - } - } - 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); - if(error) break; - error = HuffmanTree_makeFromFrequencies(&tree_d, frequencies_d.data, frequencies_d.size, 15); - if(error) break; - - numcodes_ll = tree_ll.numcodes; if(numcodes_ll > 286) numcodes_ll = 286; - numcodes_d = tree_d.numcodes; if(numcodes_d > 30) numcodes_d = 30; - /*store the code lengths of both generated trees in bitlen_lld*/ - for(i = 0; i < numcodes_ll; i++) uivector_push_back(&bitlen_lld, HuffmanTree_getLength(&tree_ll, (unsigned)i)); - for(i = 0; i < numcodes_d; i++) uivector_push_back(&bitlen_lld, HuffmanTree_getLength(&tree_d, (unsigned)i)); - - /*run-length compress bitlen_ldd into bitlen_lld_e by using repeat codes 16 (copy length 3-6 times), - 17 (3-10 zeroes), 18 (11-138 zeroes)*/ - for(i = 0; i < (unsigned)bitlen_lld.size; i++) - { - unsigned j = 0; /*amount of repititions*/ - while(i + j + 1 < (unsigned)bitlen_lld.size && bitlen_lld.data[i + j + 1] == bitlen_lld.data[i]) j++; - - if(bitlen_lld.data[i] == 0 && j >= 2) /*repeat code for zeroes*/ - { - j++; /*include the first zero*/ - if(j <= 10) /*repeat code 17 supports max 10 zeroes*/ - { - uivector_push_back(&bitlen_lld_e, 17); - uivector_push_back(&bitlen_lld_e, j - 3); - } - else /*repeat code 18 supports max 138 zeroes*/ - { - if(j > 138) j = 138; - uivector_push_back(&bitlen_lld_e, 18); - uivector_push_back(&bitlen_lld_e, j - 11); - } - i += (j - 1); - } - else if(j >= 3) /*repeat code for value other than zero*/ - { - size_t k; - unsigned num = j / 6, rest = j % 6; - uivector_push_back(&bitlen_lld_e, bitlen_lld.data[i]); - for(k = 0; k < num; k++) - { - uivector_push_back(&bitlen_lld_e, 16); - uivector_push_back(&bitlen_lld_e, 6 - 3); - } - if(rest >= 3) - { - uivector_push_back(&bitlen_lld_e, 16); - uivector_push_back(&bitlen_lld_e, rest - 3); - } - else j -= rest; - i += j; - } - else /*too short to benefit from repeat code*/ - { - uivector_push_back(&bitlen_lld_e, bitlen_lld.data[i]); - } - } - - /*generate tree_cl, the huffmantree of huffmantrees*/ - - if(!uivector_resizev(&frequencies_cl, NUM_CODE_LENGTH_CODES, 0)) ERROR_BREAK(9926 /*alloc fail*/); - for(i = 0; i < bitlen_lld_e.size; i++) - { - frequencies_cl.data[bitlen_lld_e.data[i]]++; - /*after a repeat code come the bits that specify the number of repetitions, - those don't need to be in the frequencies_cl calculation*/ - if(bitlen_lld_e.data[i] >= 16) i++; - } - - error = HuffmanTree_makeFromFrequencies(&tree_cl, frequencies_cl.data, 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++) - { - /*lenghts of code length tree is in the order as specified by deflate*/ - bitlen_cl.data[i] = HuffmanTree_getLength(&tree_cl, CLCL_ORDER[i]); - } - 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(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 - - HLIT + 257 code lenghts of lit/length alphabet (encoded using the code length - alphabet, + possible repetition codes 16, 17, 18) - - HDIST + 1 code lengths of distance alphabet (encoded using the code length - alphabet, + possible repetition codes 16, 17, 18) - - compressed data - - 256 (end code) - */ - - /*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"*/ - - /*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); - - /*write the code lenghts of the code length alphabet*/ - 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]), - 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); - } - - /*write the compressed data symbols*/ - 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)); - - break; /*end of error-while*/ - } - - /*cleanup*/ - uivector_cleanup(&lz77_encoded); - HuffmanTree_cleanup(&tree_ll); - HuffmanTree_cleanup(&tree_d); - HuffmanTree_cleanup(&tree_cl); - uivector_cleanup(&frequencies_ll); - uivector_cleanup(&frequencies_d); - uivector_cleanup(&frequencies_cl); - uivector_cleanup(&bitlen_lld_e); - uivector_cleanup(&bitlen_lld); - uivector_cleanup(&bitlen_cl); - - return error; -} - -static unsigned deflateFixed(ucvector* out, const unsigned char* data, - size_t datasize, const LodePNG_CompressSettings* settings) -{ - 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 error = 0; - size_t i, bp = 0; /*the bit pointer*/ - - HuffmanTree_init(&tree_ll); - HuffmanTree_init(&tree_d); - - 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*/ - - if(settings->useLZ77) /*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); - uivector_cleanup(&lz77_encoded); - } - else /*no LZ77, but still will be Huffman compressed*/ - { - for(i = 0; i < datasize; 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)); - - /*cleanup*/ - HuffmanTree_cleanup(&tree_ll); - HuffmanTree_cleanup(&tree_d); - - return error; -} - -static unsigned LodePNG_deflate(ucvector* out, const unsigned char* data, size_t datasize, - const LodePNG_CompressSettings* 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; - return error; -} - -#endif /*LODEPNG_COMPILE_DECODER*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Adler32 */ -/* ////////////////////////////////////////////////////////////////////////// */ - -static unsigned update_adler32(unsigned adler, const unsigned char* data, unsigned len) -{ - unsigned s1 = adler & 0xffff; - unsigned s2 = (adler >> 16) & 0xffff; - - while(len > 0) - { - /*at least 5550 sums can be done before the sums overflow, saving a lot of module divisions*/ - unsigned amount = len > 5550 ? 5550 : len; - len -= amount; - while(amount > 0) - { - s1 = (s1 + *data++); - s2 = (s2 + s1); - amount--; - } - s1 %= 65521; - s2 %= 65521; - } - - return (s2 << 16) | s1; -} - -/*Return the adler32 of the bytes data[0..len-1]*/ -static unsigned adler32(const unsigned char* data, unsigned len) -{ - return update_adler32(1L, data, len); -} - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Zlib / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -#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 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*/ - if((in[0] * 256 + in[1]) % 31 != 0) - { - /*error: 256 * in[0] + in[1] must be a multiple of 31, the FCHECK value is supposed to be made that way*/ - return 24; - } - - CM = in[0] & 15; - CINFO = (in[0] >> 4) & 15; - /*FCHECK = in[1] & 31;*/ /*FCHECK is already tested above*/ - FDICT = (in[1] >> 5) & 1; - /*FLEVEL = (in[1] >> 6) & 3;*/ /*FLEVEL is not used here*/ - - if(CM != 8 || CINFO > 7) - { - /*error: only compression method 8: inflate with sliding window of 32k is supported by the PNG spec*/ - return 25; - } - if(FDICT != 0) - { - /*error: the specification of PNG says about the zlib stream: - "The additional flags shall not specify a preset dictionary."*/ - 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; - if(error) return error; - - if(!settings->ignoreAdler32) - { - unsigned ADLER32 = LodePNG_read32bitInt(&in[insize - 4]); - unsigned checksum = adler32(outv.data, (unsigned)outv.size); - if(checksum != ADLER32) return 58; /*error, adler checksum not correct, data must be corrupted*/ - } - - return 0; /*no error*/ -} - -#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) -{ - /*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; - size_t i; - unsigned error; - - unsigned ADLER32; - /*zlib data: 1 byte CMF (CM+CINFO), 1 byte FLG, deflate data, 4 byte ADLER32 checksum of the Decompressed data*/ - unsigned CMF = 120; /*0b01111000: CM 8, CINFO 7. With CINFO 7, any window size up to 32768 can be used.*/ - unsigned FLEVEL = 0; - unsigned FDICT = 0; - unsigned CMFFLG = 256 * CMF + FDICT * 32 + FLEVEL * 64; - unsigned FCHECK = 31 - CMFFLG % 31; - CMFFLG += FCHECK; - - /*ucvector-controlled version of the output buffer, for dynamic array*/ - ucvector_init_buffer(&outv, *out, *outsize); - - 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); - - 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); - } - - *out = outv.data; - *outsize = outv.size; - - return error; -} - -#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) -{ - return 0; //Placeholder to be implemented if LODEPNG_COMPILE_ZLIB is disabled. -} -#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) -{ - return 0; //Placeholder to be implemented if LODEPNG_COMPILE_ZLIB is disabled. -} -#endif /*LODEPNG_COMPILE_ENCODER*/ - -#endif /*LODEPNG_COMPILE_ZLIB*/ - -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_ENCODER - -/*this is a good tradeoff between speed and compression ratio*/ -#define DEFAULT_WINDOWSIZE 2048 - -void LodePNG_CompressSettings_init(LodePNG_CompressSettings* 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; -} - -const LodePNG_CompressSettings LodePNG_defaultCompressSettings = {2, 1, DEFAULT_WINDOWSIZE}; - -#endif /*LODEPNG_COMPILE_ENCODER*/ - -#ifdef LODEPNG_COMPILE_DECODER - -void LodePNG_DecompressSettings_init(LodePNG_DecompressSettings* settings) -{ - settings->ignoreAdler32 = 0; -} - -const LodePNG_DecompressSettings LodePNG_defaultDecompressSettings = {0}; - -#endif /*LODEPNG_COMPILE_DECODER*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* // End of Zlib related code. Begin of PNG related code. // */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_PNG - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / CRC32 / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -static unsigned Crc32_crc_table_computed = 0; -static unsigned Crc32_crc_table[256]; - -/*Make the table for a fast CRC.*/ -static void Crc32_make_crc_table(void) -{ - unsigned c, k, n; - for(n = 0; n < 256; n++) - { - c = n; - for(k = 0; k < 8; k++) - { - if(c & 1) c = 0xedb88320L ^ (c >> 1); - else c = c >> 1; - } - Crc32_crc_table[n] = c; - } - Crc32_crc_table_computed = 1; -} - -/*Update a running CRC with the bytes buf[0..len-1]--the CRC should be -initialized to all 1's, and the transmitted value is the 1's complement of the -final running CRC (see the crc() routine below).*/ -static unsigned Crc32_update_crc(const unsigned char* buf, unsigned crc, size_t len) -{ - unsigned c = crc; - size_t n; - - if(!Crc32_crc_table_computed) Crc32_make_crc_table(); - for(n = 0; n < len; n++) - { - c = Crc32_crc_table[(c ^ buf[n]) & 0xff] ^ (c >> 8); - } - return c; -} - -/*Return the CRC of the bytes buf[0..len-1].*/ -static unsigned Crc32_crc(const unsigned char* buf, size_t len) -{ - return Crc32_update_crc(buf, 0xffffffffL, len) ^ 0xffffffffL; -} - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Reading and writing single bits and bytes from/to stream for LodePNG / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -static unsigned char readBitFromReversedStream(size_t* bitpointer, const unsigned char* bitstream) -{ - unsigned char result = (unsigned char)((bitstream[(*bitpointer) >> 3] >> (7 - ((*bitpointer) & 0x7))) & 1); - (*bitpointer)++; - return result; -} - -static unsigned readBitsFromReversedStream(size_t* bitpointer, const unsigned char* bitstream, size_t nbits) -{ - unsigned result = 0; - size_t i; - for(i = nbits - 1; i < nbits; i--) - { - result += (unsigned)readBitFromReversedStream(bitpointer, bitstream) << i; - } - return result; -} - -#ifdef LODEPNG_COMPILE_DECODER -static void setBitOfReversedStream0(size_t* bitpointer, unsigned char* bitstream, unsigned char bit) -{ - /*the current bit in bitstream must be 0 for this to work*/ - if(bit) - { - /*earlier bit of huffman code is in a lesser significant bit of an earlier byte*/ - bitstream[(*bitpointer) >> 3] |= (bit << (7 - ((*bitpointer) & 0x7))); - } - (*bitpointer)++; -} -#endif /*LODEPNG_COMPILE_DECODER*/ - -static void setBitOfReversedStream(size_t* bitpointer, unsigned char* bitstream, unsigned char bit) -{ - /*the current bit in bitstream may be 0 or 1 for this to work*/ - if(bit == 0) bitstream[(*bitpointer) >> 3] &= (unsigned char)(~(1 << (7 - ((*bitpointer) & 0x7)))); - else bitstream[(*bitpointer) >> 3] |= (1 << (7 - ((*bitpointer) & 0x7))); - (*bitpointer)++; -} - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / PNG chunks / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -unsigned LodePNG_chunk_length(const unsigned char* chunk) -{ - return LodePNG_read32bitInt(&chunk[0]); -} - -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) -{ - 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) -{ - return((chunk[4] & 32) == 0); -} - -unsigned char LodePNG_chunk_private(const unsigned char* chunk) -{ - return((chunk[6] & 32) != 0); -} - -unsigned char LodePNG_chunk_safetocopy(const unsigned char* chunk) -{ - return((chunk[7] & 32) != 0); -} - -unsigned char* LodePNG_chunk_data(unsigned char* chunk) -{ - return &chunk[8]; -} - -const unsigned char* LodePNG_chunk_data_const(const unsigned char* chunk) -{ - return &chunk[8]; -} - -unsigned LodePNG_chunk_check_crc(const unsigned char* chunk) -{ - 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); - if(CRC != checksum) return 1; - else return 0; -} - -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 char* LodePNG_chunk_next(unsigned char* chunk) -{ - 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) -{ - 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 i; - 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*/ - (*out) = new_buffer; - (*outlength) = new_length; - chunk_start = &(*out)[new_length - total_chunk_length]; - - for(i = 0; i < total_chunk_length; i++) chunk_start[i] = chunk[i]; - - return 0; -} - -unsigned LodePNG_create_chunk(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*/ - (*out) = new_buffer; - (*outlength) = new_length; - chunk = &(*out)[(*outlength) - length - 12]; - - /*1: length*/ - LodePNG_set32bitInt(chunk, (unsigned)length); - - /*2: chunk name (4 letters)*/ - chunk[4] = type[0]; - chunk[5] = type[1]; - chunk[6] = type[2]; - chunk[7] = type[3]; - - /*3: the data*/ - 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); - - return 0; -} - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Color types and such / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -/*return type is a LodePNG error code*/ -static unsigned checkColorValidity(unsigned colorType, unsigned bd) /*bd = bitDepth*/ -{ - 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*/ - case 3: if(!(bd == 1 || bd == 2 || bd == 4 || bd == 8 )) return 37; break; /*palette*/ - case 4: if(!( bd == 8 || bd == 16)) return 37; break; /*grey + alpha*/ - case 6: if(!( bd == 8 || bd == 16)) return 37; break; /*RGBA*/ - default: return 31; - } - return 0; /*allowed color type / bits combination*/ -} - -static unsigned getNumColorChannels(unsigned colorType) -{ - switch(colorType) - { - case 0: return 1; /*grey*/ - case 2: return 3; /*RGB*/ - case 3: return 1; /*palette*/ - case 4: return 2; /*grey + alpha*/ - case 6: return 4; /*RGBA*/ - } - return 0; /*unexisting color type*/ -} - -static unsigned getBpp(unsigned colorType, unsigned bitDepth) -{ - /*bits per pixel is amount of channels * bits per channel*/ - return getNumColorChannels(colorType) * bitDepth; -} - -/* ////////////////////////////////////////////////////////////////////////// */ - -void LodePNG_InfoColor_init(LodePNG_InfoColor* info) -{ - info->key_defined = 0; - info->key_r = info->key_g = info->key_b = 0; - info->colorType = 6; - info->bitDepth = 8; - info->palette = 0; - info->palettesize = 0; -} - -void LodePNG_InfoColor_cleanup(LodePNG_InfoColor* info) -{ - LodePNG_InfoColor_clearPalette(info); -} - -void LodePNG_InfoColor_clearPalette(LodePNG_InfoColor* info) -{ - if(info->palette) free(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 char* data; - /*the same resize technique as C++ std::vectors is used, and here it's made so that for a palette with - the max of 256 colors, it'll have the exact alloc size*/ - if(!(info->palettesize & (info->palettesize - 1))) /*if palettesize is 0 or a power of two*/ - { - /*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*/ - else info->palette = data; - } - info->palette[4 * info->palettesize + 0] = r; - info->palette[4 * info->palettesize + 1] = g; - info->palette[4 * info->palettesize + 2] = b; - info->palette[4 * info->palettesize + 3] = a; - info->palettesize++; - return 0; -} - -unsigned LodePNG_InfoColor_getBpp(const LodePNG_InfoColor* info) -{ - /*calculate bits per pixel out of colorType and bitDepth*/ - return getBpp(info->colorType, info->bitDepth); -} - -unsigned LodePNG_InfoColor_getChannels(const LodePNG_InfoColor* info) -{ - return getNumColorChannels(info->colorType); -} - -unsigned LodePNG_InfoColor_isGreyscaleType(const LodePNG_InfoColor* info) -{ - return info->colorType == 0 || info->colorType == 4; -} - -unsigned LodePNG_InfoColor_isAlphaType(const LodePNG_InfoColor* info) -{ - return (info->colorType & 4) != 0; -} - -unsigned LodePNG_InfoColor_isPaletteType(const LodePNG_InfoColor* info) -{ - return info->colorType == 3; -} - -unsigned LodePNG_InfoColor_hasPaletteAlpha(const LodePNG_InfoColor* info) -{ - size_t i; - for(i = 0; i < info->palettesize; i++) - { - if(info->palette[i * 4 + 3] < 255) return 1; - } - return 0; -} - -unsigned LodePNG_InfoColor_canHaveAlpha(const LodePNG_InfoColor* info) -{ - return info->key_defined - || LodePNG_InfoColor_isAlphaType(info) - || LodePNG_InfoColor_hasPaletteAlpha(info); -} - -unsigned LodePNG_InfoColor_equal(const LodePNG_InfoColor* info1, const LodePNG_InfoColor* info2) -{ - return info1->colorType == info2->colorType - && info1->bitDepth == info2->bitDepth; /*palette and color key not compared*/ -} - -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS -void LodePNG_UnknownChunks_init(LodePNG_UnknownChunks* chunks) -{ - unsigned i; - for(i = 0; i < 3; i++) chunks->data[i] = 0; - for(i = 0; i < 3; i++) chunks->datasize[i] = 0; -} - -void LodePNG_UnknownChunks_cleanup(LodePNG_UnknownChunks* chunks) -{ - unsigned i; - for(i = 0; i < 3; i++) free(chunks->data[i]); -} - -unsigned LodePNG_UnknownChunks_copy(LodePNG_UnknownChunks* dest, const LodePNG_UnknownChunks* src) -{ - unsigned i; - - LodePNG_UnknownChunks_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]; - } - - 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) -{ - text->num = 0; - text->keys = NULL; - text->langtags = NULL; - text->transkeys = NULL; - text->strings = NULL; -} - -void LodePNG_IText_cleanup(LodePNG_IText* text) -{ - LodePNG_IText_clear(text); -} - -unsigned LodePNG_IText_copy(LodePNG_IText* dest, const LodePNG_IText* 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++) - { - unsigned error = LodePNG_IText_add(dest, source->keys[i], source->langtags[i], - source->transkeys[i], source->strings[i]); - if(error) return error; - } - return 0; -} - -void LodePNG_IText_clear(LodePNG_IText* text) -{ - 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); -} - -unsigned LodePNG_IText_add(LodePNG_IText* text, const char* key, const char* langtag, - const char* transkey, 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) - { - free(new_keys); - free(new_langtags); - free(new_transkeys); - free(new_strings); - return 9934; /*alloc fail*/ - } - - text->num++; - text->keys = new_keys; - text->langtags = new_langtags; - text->transkeys = new_transkeys; - text->strings = new_strings; - - string_init(&text->keys[text->num - 1]); - string_set(&text->keys[text->num - 1], key); - - string_init(&text->langtags[text->num - 1]); - string_set(&text->langtags[text->num - 1], langtag); - - string_init(&text->transkeys[text->num - 1]); - string_set(&text->transkeys[text->num - 1], transkey); - - string_init(&text->strings[text->num - 1]); - string_set(&text->strings[text->num - 1], str); - - return 0; -} -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - -void LodePNG_InfoPng_init(LodePNG_InfoPng* info) -{ - info->width = info->height = 0; - LodePNG_InfoColor_init(&info->color); - info->interlaceMethod = 0; - info->compressionMethod = 0; - info->filterMethod = 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); - - info->time_defined = 0; - info->phys_defined = 0; -#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) -{ - LodePNG_InfoColor_cleanup(&info->color); -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - LodePNG_Text_cleanup(&info->text); - LodePNG_IText_cleanup(&info->itext); -#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 error = 0; - LodePNG_InfoPng_cleanup(dest); - *dest = *source; - LodePNG_InfoColor_init(&dest->color); - error = LodePNG_InfoColor_copy(&dest->color, &source->color); if(error) return error; - -#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*/ - -#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; -} - -void LodePNG_InfoPng_swap(LodePNG_InfoPng* a, LodePNG_InfoPng* b) -{ - LodePNG_InfoPng 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) -{ - 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; -} - -/*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*/ - - if(infoIn->bitDepth == 8) - { - switch(infoIn->colorType) - { - 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; - } - } - else if(infoIn->bitDepth == 16) - { - switch(infoIn->colorType) - { - 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; - } - } - 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] = (unsigned char)((value * 255) / highest); /*scale value from 0 to 255*/ - if(alpha) - { - if(infoIn->key_defined && value == infoIn->key_r) out[bytes * i + 1] = 0; - else out[bytes * i + 1] = 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) - { - 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[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) - { - 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; - } - } - } - return 0; -} - -/* -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. -*/ -unsigned LodePNG_convert(unsigned char* out, const unsigned char* in, LodePNG_InfoColor* infoOut, - LodePNG_InfoColor* infoIn, 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)) - { - 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; - } - else if((infoOut->colorType == 2 || infoOut->colorType == 6) && infoOut->bitDepth == 8) - { - LodePNG_convert_rgb_a_8(out, in, infoIn, numpixels, bytes, alpha); - } - else if(LodePNG_InfoColor_isGreyscaleType(infoOut) && infoOut->bitDepth == 8) - { - /*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); - } - else if((infoOut->colorType == 2 || infoOut->colorType == 6) && infoOut->bitDepth == 16) - { - LodePNG_convert_rgb_a_16(out, in, infoIn, numpixels, bytes, alpha); - } - else if(LodePNG_InfoColor_isGreyscaleType(infoOut) && infoOut->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_16(out, in, infoIn, numpixels, bytes, alpha); - } - else return 59; /*invalid color mode*/ - return 0; -} - -/* -Paeth predicter, used by PNG filter type 4 -The parameters are of type short, but should come from unsigned chars, the shorts -are only needed to make the paeth calculation correct. -*/ -static unsigned char paethPredictor(short a, short b, short c) -{ - short pa = abs(b - 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; -} - -/*shared values used by multiple Adam7 related functions*/ - -static const unsigned ADAM7_IX[7] = { 0, 4, 0, 2, 0, 1, 0 }; /*x start values*/ -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*/ - -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) -{ - /*the passstart values have 8 values: the 8th one indicates the byte after the end of the 7th (= last) pass*/ - unsigned i; - - /*calculate width and height in pixels of each pass*/ - for(i = 0; i < 7; i++) - { - passw[i] = (w + ADAM7_DX[i] - ADAM7_IX[i] - 1) / ADAM7_DX[i]; - passh[i] = (h + ADAM7_DY[i] - ADAM7_IY[i] - 1) / ADAM7_DY[i]; - if(passw[i] == 0) passh[i] = 0; - if(passh[i] == 0) passw[i] = 0; - } - - filter_passstart[0] = padded_passstart[0] = passstart[0] = 0; - for(i = 0; i < 7; i++) - { - /*if passw[i] is 0, it's 0 bytes, not 1 (no filtertype-byte)*/ - filter_passstart[i + 1] = filter_passstart[i] - + ((passw[i] && passh[i]) ? passh[i] * (1 + (passw[i] * bpp + 7) / 8) : 0); - /*bits padded if needed to fill full byte at end of each scanline*/ - padded_passstart[i + 1] = padded_passstart[i] + passh[i] * ((passw[i] * bpp + 7) / 8); - /*only padded at end of reduced image*/ - passstart[i + 1] = passstart[i] + (passh[i] * passw[i] * bpp + 7) / 8; - } -} - -#ifdef LODEPNG_COMPILE_DECODER - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / 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) -{ - if(inlength == 0 || in == 0) - { - decoder->error = 48; /*the given data is empty*/ - return; - } - if(inlength < 29) - { - decoder->error = 27; /*error: the data length is smaller than the length of a PNG header*/ - return; - } - - /*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; - - 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; - } - 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; - } - - /*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]; - - if(!decoder->settings.ignoreCrc) - { - unsigned CRC = LodePNG_read32bitInt(&in[29]); - unsigned checksum = Crc32_crc(&in[12], 17); - if(CRC != checksum) - { - decoder->error = 57; /*invalid CRC*/ - return; - } - } - - /*error: only compression method 0 is allowed in the specification*/ - if(decoder->infoPng.compressionMethod != 0) { decoder->error = 32; return; } - /*error: only filter method 0 is allowed in the specification*/ - if(decoder->infoPng.filterMethod != 0) { decoder->error = 33; return; } - /*error: only interlace methods 0 and 1 exist in the specification*/ - if(decoder->infoPng.interlaceMethod > 1) { decoder->error = 34; return; } - - decoder->error = checkColorValidity(decoder->infoPng.color.colorType, decoder->infoPng.color.bitDepth); -} - -static unsigned unfilterScanline(unsigned char* recon, const unsigned char* scanline, const unsigned char* precon, - size_t bytewidth, unsigned char filterType, size_t length) -{ - /* - For PNG filter method 0 - unfilter a PNG image scanline by scanline. when the pixels are smaller than 1 byte, - the filter works byte per byte (bytewidth = 1) - precon is the previous unfiltered scanline, recon the result, scanline the current one - the incoming scanlines do NOT include the filtertype byte, that one is given in the parameter filterType instead - recon and scanline MAY be the same memory address! precon must be disjoint. - */ - - size_t i; - switch(filterType) - { - case 0: - 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]; - break; - case 2: - if(precon) - { - for(i = 0; i < length; i++) recon[i] = scanline[i] + precon[i]; - } - else - { - for(i = 0; i < length; i++) recon[i] = scanline[i]; - } - break; - 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); - } - 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; - } - break; - case 4: - if(precon) - { - for(i = 0; i < bytewidth; i++) - { - recon[i] = (scanline[i] + precon[i]); /*paethPredictor(0, precon[i], 0) is always precon[i]*/ - } - for(i = bytewidth; i < length; i++) - { - recon[i] = (scanline[i] + paethPredictor(recon[i - bytewidth], precon[i], precon[i - bytewidth])); - } - } - else - { - for(i = 0; i < bytewidth; i++) - { - recon[i] = scanline[i]; - } - for(i = bytewidth; i < length; i++) - { - /*paethPredictor(recon[i - bytewidth], 0, 0) is always recon[i - bytewidth]*/ - recon[i] = (scanline[i] + recon[i - bytewidth]); - } - } - break; - default: return 36; /*error: unexisting filter type given*/ - } - return 0; -} - -static unsigned unfilter(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, unsigned bpp) -{ - /* - For PNG filter method 0 - this function unfilters a single image (e.g. without interlacing this is called once, with Adam7 seven times) - out must have enough bytes allocated already, in must have the scanlines + 1 filtertype byte per scanline - w and h are image dimensions or dimensions of reduced image, bpp is bits per pixel - in and out are allowed to be the same memory address (but aren't the same size since in has the extra filter bytes) - */ - - unsigned y; - unsigned char* prevline = 0; - - /*bytewidth is used for filtering, is 1 when bpp < 8, number of bytes per pixel otherwise*/ - size_t bytewidth = (bpp + 7) / 8; - size_t linebytes = (w * bpp + 7) / 8; - - for(y = 0; y < h; y++) - { - size_t outindex = linebytes * y; - 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; - - prevline = &out[outindex]; - } - - return 0; -} - -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; - - Adam7_getpassvalues(passw, passh, filter_passstart, padded_passstart, passstart, w, h, bpp); - - if(bpp >= 8) - { - for(i = 0; i < 7; i++) - { - unsigned x, y, b; - size_t bytewidth = bpp / 8; - for(y = 0; y < passh[i]; y++) - for(x = 0; x < passw[i]; x++) - { - size_t pixelinstart = passstart[i] + (y * passw[i] + x) * bytewidth; - size_t pixeloutstart = ((ADAM7_IY[i] + y * ADAM7_DY[i]) * w + ADAM7_IX[i] + x * ADAM7_DX[i]) * bytewidth; - for(b = 0; b < bytewidth; b++) - { - out[pixeloutstart + b] = in[pixelinstart + b]; - } - } - } - } - else /*bpp < 8: Adam7 with pixels < 8 bit is a bit trickier: with bit pointers*/ - { - for(i = 0; i < 7; i++) - { - unsigned x, y, b; - unsigned ilinebits = bpp * passw[i]; - unsigned olinebits = bpp * w; - size_t obp, ibp; /*bit pointers (for out and in buffer)*/ - for(y = 0; y < passh[i]; y++) - for(x = 0; x < passw[i]; x++) - { - ibp = (8 * passstart[i]) + (y * ilinebits + x * bpp); - obp = (ADAM7_IY[i] + y * ADAM7_DY[i]) * olinebits + (ADAM7_IX[i] + x * ADAM7_DX[i]) * bpp; - for(b = 0; b < bpp; b++) - { - unsigned char bit = readBitFromReversedStream(&ibp, in); - /*note that this function assumes the out buffer is completely 0, use setBitOfReversedStream otherwise*/ - setBitOfReversedStream0(&obp, out, bit); - } - } - } - } -} - -static void removePaddingBits(unsigned char* out, const unsigned char* in, - size_t olinebits, size_t ilinebits, unsigned h) -{ - /* - After filtering there are still padding bits if scanlines have non multiple of 8 bit amounts. They need - to be removed (except at last scanline of (Adam7-reduced) image) before working with pure image buffers - for the Adam7 code, the color convert code and the output to the user. - in and out are allowed to be the same buffer, in may also be higher but still overlapping; in must - have >= ilinebits*h bits, out must have >= olinebits*h bits, olinebits must be <= ilinebits - also used to move bits after earlier such operations happened, e.g. in a sequence of reduced images from Adam7 - only useful if (ilinebits - olinebits) is a value in the range 1..7 - */ - unsigned y; - size_t diff = ilinebits - olinebits; - size_t ibp = 0, obp = 0; /*input and output bit pointers*/ - for(y = 0; y < h; y++) - { - size_t x; - for(x = 0; x < olinebits; x++) - { - unsigned char bit = readBitFromReversedStream(&ibp, in); - setBitOfReversedStream(&obp, out, bit); - } - ibp += diff; - } -} - -/*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) -{ - /* - This function converts the filtered-padded-interlaced data into pure 2D image buffer with the PNG's colortype. - Steps: - *) if no Adam7: 1) unfilter 2) remove padding bits (= posible extra bits per scanline if bpp < 8) - *) 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; - if(bpp == 0) return 31; /*error: invalid colortype*/ - - if(infoPng->interlaceMethod == 0) - { - if(bpp < 8 && w * bpp != ((w * bpp + 7) / 8) * 8) - { - error = unfilter(in, in, w, h, bpp); - if(error) return error; - 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*/ - } - else /*interlaceMethod is 1 (Adam7)*/ - { - 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); - - 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; - /*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) - { - /*remove padding bits in scanlines; after this there still may be padding - bits between the different reduced images: each reduced image still starts nicely at a byte*/ - removePaddingBits(&in[passstart[i]], &in[padded_passstart[i]], passw[i] * bpp, - ((passw[i] * bpp + 7) / 8) * 8, passh[i]); - } - } - - Adam7_deinterlace(out, in, w, h, bpp); - } - - return error; -} - -/*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, - const unsigned char* in, size_t insize) -{ - unsigned char IEND = 0; - const unsigned char* chunk; - size_t i; - ucvector idat; /*the data from idat chunks*/ - - /*for unknown chunk order*/ - unsigned unknown = 0; -#ifdef LODEPNG_COMPILE_UNKNOWN_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; - - 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) - { - 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); - - /*length of the data of the chunk, excluding the length bytes, chunk type and CRC bytes*/ - chunkLength = LodePNG_chunk_length(chunk); - /*error: chunk length larger than the max PNG chunk size*/ - if(chunkLength > 2147483647) CERROR_BREAK(decoder->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*/ - } - - data = LodePNG_chunk_data_const(chunk); - - /*IDAT chunk, containing compressed image data*/ - 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*/); - for(i = 0; i < chunkLength; i++) idat.data[oldsize + i] = data[i]; -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS - critical_pos = 3; -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ - } - /*IEND chunk*/ - else if(LodePNG_chunk_type_equals(chunk, "IEND")) - { - IEND = 1; - } - /*palette 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 - critical_pos = 2; -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ - } - /*palette transparency 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*/ - } -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /*background color 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]; - } - } - /*text chunk (tEXt)*/ - else if(LodePNG_chunk_type_equals(chunk, "tEXt")) - { - if(decoder->settings.readTextChunks) - { - 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); - } - } - /*compressed text chunk (zTXt)*/ - else if(LodePNG_chunk_type_equals(chunk, "zTXt")) - { - if(decoder->settings.readTextChunks) - { - 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; - } - } - /*international text chunk (iTXt)*/ - else if(LodePNG_chunk_type_equals(chunk, "iTXt")) - { - if(decoder->settings.readTextChunks) - { - 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; - } - } - 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]; - } - 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]; - } -#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); - - unknown = 1; -#ifdef LODEPNG_COMPILE_UNKNOWN_CHUNKS - if(decoder->settings.rememberUnknownChunks) - { - 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; - } -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ - } - - if(!decoder->settings.ignoreCrc && !unknown) /*check CRC if wanted, only on known chunk types*/ - { - if(LodePNG_chunk_check_crc(chunk)) CERROR_BREAK(decoder->error, 57); /*invalid CRC*/ - } - - if(!IEND) chunk = LodePNG_chunk_next_const(chunk); - } - - if(!decoder->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)) - { - decoder->error = 9945; /*alloc fail*/ - } - if(!decoder->error) - { - /*decompress with the Zlib decompressor*/ - decoder->error = LodePNG_zlib_decompress(&scanlines.data, &scanlines.size, idat.data, - idat.size, &decoder->settings.zlibsettings); - } - - if(!decoder->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); - *out = outv.data; - *outsize = outv.size; - } - ucvector_cleanup(&scanlines); - } - - ucvector_cleanup(&idat); -} - -void LodePNG_Decoder_decode(LodePNG_Decoder* decoder, unsigned char** out, size_t* outsize, - 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)) - { - /*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 - the raw image has to the end user*/ - if(!decoder->settings.color_convert) - { - decoder->error = LodePNG_InfoColor_copy(&decoder->infoRaw.color, &decoder->infoPng.color); - if(decoder->error) return; - } - } - else - { - /*color conversion needed; sort of copy of the data*/ - unsigned char* data = *out; - - /*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)) - { - decoder->error = 56; /*unsupported color mode conversion*/ - return; - } - - *outsize = (decoder->infoPng.width * decoder->infoPng.height - * LodePNG_InfoColor_getBpp(&decoder->infoRaw.color) + 7) / 8; - *out = (unsigned char*)malloc(*outsize); - if(!(*out)) - { - decoder->error = 9947; /*alloc fail*/ - *outsize = 0; - } - else decoder->error = LodePNG_convert(*out, data, &decoder->infoRaw.color, &decoder->infoPng.color, - decoder->infoPng.width, decoder->infoPng.height); - free(data); - } -} - -unsigned LodePNG_decode(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, - size_t insize, unsigned 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); - return error; -} - -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); -} - -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); -} - -#ifdef LODEPNG_COMPILE_DISK -unsigned LodePNG_decode_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename, - unsigned 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); - return error; -} - -unsigned LodePNG_decode32_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename) -{ - return LodePNG_decode_file(out, w, h, filename, 6, 8); -} - -unsigned LodePNG_decode24_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename) -{ - return LodePNG_decode_file(out, w, h, filename, 2, 8); -} -#endif /*LODEPNG_COMPILE_DISK*/ - -void LodePNG_DecodeSettings_init(LodePNG_DecodeSettings* settings) -{ - settings->color_convert = 1; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - settings->readTextChunks = 1; -#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; -} - -#endif /*LODEPNG_COMPILE_DECODER*/ - -#ifdef LODEPNG_COMPILE_ENCODER - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / PNG Encoder / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -/*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; - out->allocsize = out->size; /*fix the allocsize again*/ - return 0; -} - -static void writeSignature(ucvector* out) -{ - /*8 bytes PNG signature, aka the magic bytes*/ - ucvector_push_back(out, 137); - ucvector_push_back(out, 80); - ucvector_push_back(out, 78); - ucvector_push_back(out, 71); - ucvector_push_back(out, 13); - ucvector_push_back(out, 10); - ucvector_push_back(out, 26); - ucvector_push_back(out, 10); -} - -static unsigned addChunk_IHDR(ucvector* out, unsigned w, unsigned h, unsigned bitDepth, - unsigned colorType, unsigned interlaceMethod) -{ - 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*/ - ucvector_push_back(&header, 0); /*compression method*/ - ucvector_push_back(&header, 0); /*filter method*/ - ucvector_push_back(&header, interlaceMethod); /*interlace method*/ - - error = addChunk(out, "IHDR", header.data, header.size); - ucvector_cleanup(&header); - - return error; -} - -static unsigned addChunk_PLTE(ucvector* out, const LodePNG_InfoColor* info) -{ - unsigned error = 0; - size_t i; - ucvector PLTE; - ucvector_init(&PLTE); - for(i = 0; i < info->palettesize * 4; i++) - { - /*add all channels except alpha channel*/ - if(i % 4 != 3) ucvector_push_back(&PLTE, info->palette[i]); - } - error = addChunk(out, "PLTE", PLTE.data, PLTE.size); - ucvector_cleanup(&PLTE); - - return error; -} - -static unsigned addChunk_tRNS(ucvector* out, const LodePNG_InfoColor* info) -{ - unsigned error = 0; - size_t i; - ucvector tRNS; - ucvector_init(&tRNS); - if(info->colorType == 3) - { - /*add only alpha channel*/ - for(i = 0; i < info->palettesize; i++) ucvector_push_back(&tRNS, info->palette[4 * i + 3]); - } - else if(info->colorType == 0) - { - if(info->key_defined) - { - ucvector_push_back(&tRNS, (unsigned char)(info->key_r / 256)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_r % 256)); - } - } - else if(info->colorType == 2) - { - if(info->key_defined) - { - ucvector_push_back(&tRNS, (unsigned char)(info->key_r / 256)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_r % 256)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_g / 256)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_g % 256)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_b / 256)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_b % 256)); - } - } - - error = addChunk(out, "tRNS", tRNS.data, tRNS.size); - ucvector_cleanup(&tRNS); - - return error; -} - -static unsigned addChunk_IDAT(ucvector* out, const unsigned char* data, size_t datasize, - LodePNG_CompressSettings* 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); - if(!error) error = addChunk(out, "IDAT", zlibdata.data, zlibdata.size); - ucvector_cleanup(&zlibdata); - - return error; -} - -static unsigned addChunk_IEND(ucvector* out) -{ - unsigned error = 0; - error = addChunk(out, "IEND", 0, 0); - return error; -} - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - -static unsigned addChunk_tEXt(ucvector* out, const char* keyword, const char* textstring) -{ - unsigned error = 0; - size_t i; - 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); - 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); - - return error; -} - -static unsigned addChunk_zTXt(ucvector* out, const char* keyword, const char* textstring, - LodePNG_CompressSettings* zlibsettings) -{ - unsigned error = 0; - ucvector data, compressed; - size_t i, textsize = strlen(textstring); - - 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*/ - ucvector_push_back(&data, 0); /*compression method: 0*/ - - error = LodePNG_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]); - error = addChunk(out, "zTXt", data.data, data.size); - } - - ucvector_cleanup(&compressed); - ucvector_cleanup(&data); - return error; -} - -static unsigned addChunk_iTXt(ucvector* out, unsigned compressed, const char* keyword, const char* langtag, - const char* transkey, const char* textstring, LodePNG_CompressSettings* zlibsettings) -{ - unsigned error = 0; - ucvector data, compressed_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]); - ucvector_push_back(&data, 0); /*null termination char*/ - ucvector_push_back(&data, compressed ? 1 : 0); /*compression flag*/ - ucvector_push_back(&data, 0); /*compression method*/ - for(i = 0; langtag[i] != 0; i++) ucvector_push_back(&data, (unsigned char)langtag[i]); - ucvector_push_back(&data, 0); /*null termination char*/ - for(i = 0; transkey[i] != 0; i++) ucvector_push_back(&data, (unsigned char)transkey[i]); - ucvector_push_back(&data, 0); /*null termination char*/ - - if(compressed) - { - ucvector_init(&compressed_data); - error = LodePNG_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]); - } - } - else /*not compressed*/ - { - for(i = 0; textstring[i] != 0; i++) ucvector_push_back(&data, (unsigned char)textstring[i]); - } - - if(!error) error = addChunk(out, "iTXt", data.data, data.size); - ucvector_cleanup(&data); - return error; -} - -static unsigned addChunk_bKGD(ucvector* out, const LodePNG_InfoPng* info) -{ - unsigned error = 0; - ucvector bKGD; - ucvector_init(&bKGD); - if(info->color.colorType == 0 || info->color.colorType == 4) - { - 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) - { - ucvector_push_back(&bKGD, (unsigned char)(info->background_r / 256)); - ucvector_push_back(&bKGD, (unsigned char)(info->background_r % 256)); - ucvector_push_back(&bKGD, (unsigned char)(info->background_g / 256)); - ucvector_push_back(&bKGD, (unsigned char)(info->background_g % 256)); - 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) - { - ucvector_push_back(&bKGD, (unsigned char)(info->background_r % 256)); /*palette index*/ - } - - error = addChunk(out, "bKGD", bKGD.data, bKGD.size); - ucvector_cleanup(&bKGD); - - return error; -} - -static unsigned addChunk_tIME(ucvector* out, const LodePNG_Time* time) -{ - unsigned error = 0; - unsigned char* data = (unsigned char*)malloc(7); - if(!data) return 9948; /*alloc fail*/ - data[0] = (unsigned char)(time->year / 256); - data[1] = (unsigned char)(time->year % 256); - data[2] = time->month; - data[3] = time->day; - data[4] = time->hour; - data[5] = time->minute; - data[6] = time->second; - error = addChunk(out, "tIME", data, 7); - free(data); - return error; -} - -static unsigned addChunk_pHYs(ucvector* out, const LodePNG_InfoPng* info) -{ - unsigned error = 0; - ucvector data; - ucvector_init(&data); - - 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); - ucvector_cleanup(&data); - - return error; -} - -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - -static void filterScanline(unsigned char* out, const unsigned char* scanline, const unsigned char* prevline, - size_t length, size_t bytewidth, unsigned char filterType) -{ - size_t i; - switch(filterType) - { - case 0: /*None*/ - for(i = 0; i < length; i++) out[i] = scanline[i]; - break; - case 1: /*Sub*/ - 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]; - } - else - { - for(i = 0; i < bytewidth; i++) out[i] = scanline[i]; - for(i = bytewidth; i < length; i++) out[i] = scanline[i] - scanline[i - bytewidth]; - } - break; - case 2: /*Up*/ - if(prevline) - { - for(i = 0; i < length; i++) out[i] = scanline[i] - prevline[i]; - } - else - { - for(i = 0; i < length; i++) out[i] = scanline[i]; - } - break; - case 3: /*Average*/ - if(prevline) - { - for(i = 0; i < bytewidth; i++) out[i] = scanline[i] - prevline[i] / 2; - for(i = bytewidth; i < length; i++) out[i] = scanline[i] - ((scanline[i - bytewidth] + prevline[i]) / 2); - } - else - { - for(i = 0; i < bytewidth; i++) out[i] = scanline[i]; - for(i = bytewidth; i < length; i++) out[i] = scanline[i] - scanline[i - bytewidth] / 2; - } - break; - case 4: /*Paeth*/ - if(prevline) - { - /*paethPredictor(0, prevline[i], 0) is always prevline[i]*/ - for(i = 0; i < bytewidth; i++) out[i] = (scanline[i] - prevline[i]); - for(i = bytewidth; i < length; i++) - { - out[i] = (scanline[i] - paethPredictor(scanline[i - bytewidth], prevline[i], prevline[i - bytewidth])); - } - } - else - { - for(i = 0; i < bytewidth; i++) out[i] = scanline[i]; - /*paethPredictor(scanline[i - bytewidth], 0, 0) is always scanline[i - bytewidth]*/ - for(i = bytewidth; i < length; i++) out[i] = (scanline[i] - scanline[i - bytewidth]); - } - break; - default: return; /*unexisting filter type given*/ - } -} - -static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, - const LodePNG_InfoColor* info, const LodePNG_EncodeSettings* settings) -{ - /* - For PNG filter method 0 - out must be a buffer with as size: h + (w * h * bpp + 7) / 8, because there are - the scanlines with 1 extra byte per scanline - */ - - unsigned bpp = LodePNG_InfoColor_getBpp(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*/ - size_t bytewidth = (bpp + 7) / 8; - const unsigned char* prevline = 0; - unsigned x, y; - unsigned error = 0; - - if(bpp == 0) return 31; /*error: invalid color type*/ - - if(!settings->bruteForceFilters) - { - /* - 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; - 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++) - { - 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) - { - /*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]; - } - } - - 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 - { - /*brute force filter chooser. - deflate the scanline after every filter attempt to see which one deflates best. - This is very slow and gives only slightly smaller, sometimes even larger, result*/ - size_t size[5]; - ucvector attempt[5]; /*five filtering attempts, one for each filter type*/ - size_t smallest; - unsigned type = 0, bestType = 0; - unsigned char* dummy; - LodePNG_CompressSettings 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; - for(type = 0; type < 5; type++) - { - ucvector_init(&attempt[type]); - ucvector_resize(&attempt[type], linebytes); /*todo: give error if resize failed*/ - } - for(y = 0; y < h; y++) /*try the 5 filter types*/ - { - 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;*/ - - 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); - /*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) - { - bestType = type; - smallest = size[type]; - } - } - prevline = &in[y * linebytes]; - 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]); - } - - return error; -} - -static void addPaddingBits(unsigned char* out, const unsigned char* in, - size_t olinebits, size_t ilinebits, unsigned h) -{ - /*The opposite of the removePaddingBits function - olinebits must be >= ilinebits*/ - unsigned y; - size_t diff = olinebits - ilinebits; - size_t obp = 0, ibp = 0; /*bit pointers*/ - for(y = 0; y < h; y++) - { - size_t x; - for(x = 0; x < ilinebits; x++) - { - unsigned char bit = readBitFromReversedStream(&ibp, in); - setBitOfReversedStream(&obp, out, bit); - } - /*obp += diff; --> no, fill in some value in the padding bits too, to avoid - "Use of uninitialised value of size ###" warning from valgrind*/ - for(x = 0; x < diff; x++) setBitOfReversedStream(&obp, out, 0); - } -} - -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; - - Adam7_getpassvalues(passw, passh, filter_passstart, padded_passstart, passstart, w, h, bpp); - - if(bpp >= 8) - { - for(i = 0; i < 7; i++) - { - unsigned x, y, b; - size_t bytewidth = bpp / 8; - for(y = 0; y < passh[i]; y++) - for(x = 0; x < passw[i]; x++) - { - size_t pixelinstart = ((ADAM7_IY[i] + y * ADAM7_DY[i]) * w + ADAM7_IX[i] + x * ADAM7_DX[i]) * bytewidth; - size_t pixeloutstart = passstart[i] + (y * passw[i] + x) * bytewidth; - for(b = 0; b < bytewidth; b++) - { - out[pixeloutstart + b] = in[pixelinstart + b]; - } - } - } - } - else /*bpp < 8: Adam7 with pixels < 8 bit is a bit trickier: with bit pointers*/ - { - for(i = 0; i < 7; i++) - { - unsigned x, y, b; - unsigned ilinebits = bpp * passw[i]; - unsigned olinebits = bpp * w; - size_t obp, ibp; /*bit pointers (for out and in buffer)*/ - for(y = 0; y < passh[i]; y++) - for(x = 0; x < passw[i]; x++) - { - ibp = (ADAM7_IY[i] + y * ADAM7_DY[i]) * olinebits + (ADAM7_IX[i] + x * ADAM7_DX[i]) * bpp; - obp = (8 * passstart[i]) + (y * ilinebits + x * bpp); - for(b = 0; b < bpp; b++) - { - unsigned char bit = readBitFromReversedStream(&ibp, in); - setBitOfReversedStream(&obp, out, bit); - } - } - } - } -} - -/*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) -{ - /* - 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 error = 0; - - if(infoPng->interlaceMethod == 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*/ - - 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*/ - if(!error) - { - addPaddingBits(padded.data, in, ((w * bpp + 7) / 8) * 8, w * bpp, h); - error = filter(*out, padded.data, w, h, &infoPng->color, settings); - } - ucvector_cleanup(&padded); - } - else - { - /*we can immediatly filter into the out buffer, no other steps needed*/ - error = filter(*out, in, w, h, &infoPng->color, settings); - } - } - } - else /*interlaceMethod 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*/ - - while(!error) /*not a real while loop, used to break out to cleanup to avoid a goto*/ - { - 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); - } - else - { - error = filter(&(*out)[filter_passstart[i]], &adam7[padded_passstart[i]], - passw[i], passh[i], &infoPng->color, settings); - } - } - - break; - } - - free(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) -{ - size_t i; - for(i = 0; i < palettesize; i++) - { - if(palette[4 * i + 3] != 255) return 0; - } - return 1; -} - -/*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 -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*/ - out->allocsize = out->size; /*fix the allocsize again*/ - inchunk = LodePNG_chunk_next(inchunk); - } - return 0; -} -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ - -void LodePNG_Encoder_encode(LodePNG_Encoder* encoder, unsigned char** out, size_t* outsize, - const unsigned char* image, unsigned w, unsigned h) -{ - LodePNG_InfoPng info; - ucvector outv; - unsigned char* data = 0; /*uncompressed version of the IDAT chunk data*/ - size_t datasize = 0; - - /*provide some proper output values if error will happen*/ - *out = 0; - *outsize = 0; - encoder->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; - - if(encoder->settings.autoLeaveOutAlphaChannel && isFullyOpaque(image, w, h, &encoder->infoRaw.color)) - { - /*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; - } - - if(encoder->settings.zlibsettings.windowSize > 32768) - { - encoder->error = 60; /*error: windowsize larger than allowed*/ - return; - } - 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(!LodePNG_InfoColor_equal(&encoder->infoRaw.color, &info.color)) - { - unsigned char* converted; - size_t size = (w * h * LodePNG_InfoColor_getBpp(&info.color) + 7) / 8; - - if((info.color.colorType != 6 && info.color.colorType != 2) || (info.color.bitDepth != 8)) - { - encoder->error = 59; /*for the output image, only these types are supported*/ - return; - } - 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); - } - else preProcessScanlines(&data, &datasize, image, &info, &encoder->settings); - - ucvector_init(&outv); - while(!encoder->error) /*while only executed once, to break on error*/ - { -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - size_t i; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - /*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 - /*unknown chunks between IHDR and PLTE*/ - if(info.unknown_chunks.data[0]) - { - encoder->error = addUnknownChunks(&outv, info.unknown_chunks.data[0], info.unknown_chunks.datasize[0]); - if(encoder->error) break; - } -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ - /*PLTE*/ - if(info.color.colorType == 3) - { - 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(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)) - { - addChunk_tRNS(&outv, &info.color); - } - if((info.color.colorType == 0 || info.color.colorType == 2) && info.color.key_defined) - { - addChunk_tRNS(&outv, &info.color); - } -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /*bKGD (must come between PLTE and the IDAt chunks*/ - 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]) - { - encoder->error = addUnknownChunks(&outv, info.unknown_chunks.data[1], info.unknown_chunks.datasize[1]); - if(encoder->error) break; - } -#endif /*LODEPNG_COMPILE_UNKNOWN_CHUNKS*/ - /*IDAT (multiple IDAT chunks must be consecutive)*/ - encoder->error = addChunk_IDAT(&outv, data, datasize, &encoder->settings.zlibsettings); - if(encoder->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++) - { - if(strlen(info.text.keys[i]) > 79) - { - encoder->error = 66; /*text chunk too large*/ - break; - } - if(strlen(info.text.keys[i]) < 1) - { - encoder->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); - else - addChunk_tEXt(&outv, info.text.keys[i], info.text.strings[i]); - } - /*LodePNG version id in text chunk*/ - if(encoder->settings.add_id) - { - unsigned alread_added_id_text = 0; - for(i = 0; i < info.text.num; i++) - { - if(!strcmp(info.text.keys[i], "LodePNG")) - { - alread_added_id_text = 1; - break; - } - } - if(alread_added_id_text == 0) - addChunk_tEXt(&outv, "LodePNG", VERSION_STRING); /*it's shorter as tEXt than as zTXt chunk*/ - } - /*iTXt*/ - for(i = 0; i < info.itext.num; i++) - { - if(strlen(info.itext.keys[i]) > 79) - { - encoder->error = 66; /*text chunk too large*/ - break; - } - if(strlen(info.itext.keys[i]) < 1) - { - encoder->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); - } -#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); - /*instead of cleaning the vector up, give it to the output*/ - *out = outv.data; - *outsize = outv.size; -} - -unsigned LodePNG_encode(unsigned char** out, size_t* outsize, const unsigned char* image, - unsigned w, unsigned h, unsigned 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); - return error; -} - -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); -} - -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); -} - -#ifdef LODEPNG_COMPILE_DISK -unsigned LodePNG_encode_file(const char* filename, const unsigned char* image, unsigned w, unsigned h, - unsigned 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); - return error; -} - -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); -} - -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); -} -#endif /*LODEPNG_COMPILE_DISK*/ - -void LodePNG_EncodeSettings_init(LodePNG_EncodeSettings* settings) -{ - LodePNG_CompressSettings_init(&settings->zlibsettings); - settings->bruteForceFilters = 0; - settings->autoLeaveOutAlphaChannel = 1; - settings->force_palette = 0; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - settings->add_id = 1; - settings->text_compression = 0; -#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) -{ - switch(code) - { - case 0: return "no error, everything went ok"; - case 1: return "nothing done yet"; /*the Encoder/Decoder has done nothing yet, error checking makes no sense yet*/ - case 10: return "end of input memory reached without huffman end code"; /*while huffman decoding*/ - case 11: return "error in code tree made it jump outside of huffman tree"; /*while huffman decoding*/ - case 13: return "problem while processing dynamic deflate block"; - case 14: return "problem while processing dynamic deflate block"; - case 15: return "problem while processing dynamic deflate block"; - case 16: return "unexisting code while processing dynamic deflate block"; - case 17: return "end of out buffer memory reached while inflating"; - case 18: return "invalid distance code while inflating"; - 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"; - case 26: return "FDICT encountered in zlib header while it's not used for PNG"; - case 27: return "PNG file is smaller than a PNG header"; - /*Checks the magic file header, the first 8 bytes of the PNG file*/ - case 28: return "incorrect PNG signature, it's no PNG or corrupted"; - case 29: return "first chunk is not the header chunk"; - case 30: return "chunk length too large, chunk broken off at end of file"; - case 31: return "illegal PNG color type or bpp"; - case 32: return "illegal PNG compression method"; - case 33: return "illegal PNG filter method"; - case 34: return "illegal PNG interlace method"; - case 35: return "chunk length of a chunk is too large or the chunk too small"; - case 36: return "illegal PNG filter type encountered"; - case 37: return "illegal bit depth for this color type given"; - case 38: return "the palette is too big"; /*more than 256 colors*/ - case 39: return "more palette alpha values given in tRNS chunk than there are colors in the palette"; - case 40: return "tRNS chunk has wrong size for greyscale image"; - case 41: return "tRNS chunk has wrong size for RGB image"; - case 42: return "tRNS chunk appeared while it was not allowed for this color type"; - case 43: return "bKGD chunk has wrong size for palette image"; - case 44: return "bKGD chunk has wrong size for greyscale image"; - case 45: return "bKGD chunk has wrong size for RGB image"; - /*Is the palette too small?*/ - case 46: return "a value in indexed image is larger than the palette size (bitdepth = 8)"; - /*Is the palette too small?*/ - case 47: return "a value in indexed image is larger than the palette size (bitdepth < 8)"; - /*the input data is empty, maybe a PNG file doesn't exist or is in the wrong path*/ - case 48: return "empty input or file doesn't exist"; - case 49: return "jumped past memory while generating dynamic huffman tree"; - case 50: return "jumped past memory while generating dynamic huffman tree"; - 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"; - - /*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 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 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 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 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"; - case 69: return "unknown chunk type with 'critical' flag encountered by the decoder"; - case 71: return "unexisting interlace mode given to encoder (must be 0 or 1)"; - case 72: return "while decoding, unexisting compression method encountering in zTXt or iTXt chunk (it must be 0)"; - case 73: return "invalid tIME chunk size"; - case 74: return "invalid pHYs chunk size"; - /*length could be wrong, or data chopped off*/ - case 75: return "no null termination char found while decoding text chunk"; - case 76: return "iTXt chunk too short to contain required bytes"; - case 77: return "integer overflow in buffer size"; - case 78: return "failed to open file for reading"; /*file doesn't exist or couldn't be opened for reading*/ - 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*/ - } - - 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. // */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef __cplusplus -namespace LodePNG -{ -#ifdef LODEPNG_COMPILE_DISK - void loadFile(std::vector<unsigned char>& 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(); - - /*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<unsigned char>& 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<unsigned char>& out, const unsigned char* in, size_t insize, - const LodePNG_DecompressSettings& settings) - { - 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; - } - - unsigned decompress(std::vector<unsigned char>& out, const std::vector<unsigned char>& in, - const LodePNG_DecompressSettings& settings) - { - return decompress(out, in.empty() ? 0 : &in[0], in.size(), settings); - } -#endif //LODEPNG_COMPILE_DECODER - -#ifdef LODEPNG_COMPILE_ENCODER - unsigned compress(std::vector<unsigned char>& out, const unsigned char* in, size_t insize, - const LodePNG_CompressSettings& settings) - { - 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; - } - - unsigned compress(std::vector<unsigned char>& out, const std::vector<unsigned char>& in, - const LodePNG_CompressSettings& 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); - } - - void Decoder::operator=(const LodePNG_Decoder& other) - { - LodePNG_Decoder_copy(this, &other); - } - - bool Decoder::hasError() const - { - return error != 0; - } - unsigned Decoder::getError() const - { - return error; - } - - 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<unsigned char>& 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<unsigned char>& out, const std::vector<unsigned char>& 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<unsigned char>& 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<unsigned char>& 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<unsigned char>& out, const std::vector<unsigned char>& 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 - - /* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_DECODER - - unsigned decode(std::vector<unsigned char>& out, unsigned& w, unsigned& h, const unsigned char* in, - size_t insize, unsigned colorType, unsigned bitDepth) - { - 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(); - } - - unsigned decode(std::vector<unsigned char>& out, unsigned& w, unsigned& h, - const std::vector<unsigned char>& in, unsigned colorType, unsigned bitDepth) - { - return decode(out, w, h, in.empty() ? 0 : &in[0], (unsigned)in.size(), colorType, bitDepth); - } - -#ifdef LODEPNG_COMPILE_DISK - unsigned decode(std::vector<unsigned char>& out, unsigned& w, unsigned& h, const std::string& filename, - unsigned colorType, unsigned bitDepth) - { - std::vector<unsigned char> buffer; - loadFile(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<unsigned char>& out, const unsigned char* in, unsigned w, unsigned h, - unsigned colorType, unsigned bitDepth) - { - 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(); - } - - unsigned encode(std::vector<unsigned char>& out, const std::vector<unsigned char>& in, unsigned w, unsigned h, - unsigned colorType, unsigned bitDepth) - { - return encode(out, in.empty() ? 0 : &in[0], w, h, colorType, bitDepth); - } - -#ifdef LODEPNG_COMPILE_DISK - unsigned encode(const std::string& filename, const unsigned char* in, unsigned w, unsigned h, - unsigned colorType, unsigned bitDepth) - { - std::vector<unsigned char> 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 std::vector<unsigned char>& in, unsigned w, unsigned h, - unsigned colorType, unsigned bitDepth) - { - 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*/ |