diff options
Diffstat (limited to 'lodepng.cpp')
| -rw-r--r-- | lodepng.cpp | 6991 |
1 files changed, 0 insertions, 6991 deletions
diff --git a/lodepng.cpp b/lodepng.cpp deleted file mode 100644 index 6ab9694903e4..000000000000 --- a/lodepng.cpp +++ /dev/null @@ -1,6991 +0,0 @@ -/* -LodePNG version 20230410 - -Copyright (c) 2005-2023 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" - -#ifdef LODEPNG_COMPILE_DISK -#include <limits.h> /* LONG_MAX */ -#include <stdio.h> /* file handling */ -#endif /* LODEPNG_COMPILE_DISK */ - -#ifdef LODEPNG_COMPILE_ALLOCATORS -#include <stdlib.h> /* allocations */ -#endif /* LODEPNG_COMPILE_ALLOCATORS */ - -#if defined(_MSC_VER) && (_MSC_VER >= 1310) /*Visual Studio: A few warning types are not desired here.*/ -#pragma warning( disable : 4244 ) /*implicit conversions: not warned by gcc -Wall -Wextra and requires too much casts*/ -#pragma warning( disable : 4996 ) /*VS does not like fopen, but fopen_s is not standard C so unusable here*/ -#endif /*_MSC_VER */ - -const char* LODEPNG_VERSION_STRING = "20230410"; - -/* -This source file is divided into 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. // */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ - -/*The malloc, realloc and free functions defined here with "lodepng_" in front -of the name, so that you can easily change them to others related to your -platform if needed. Everything else in the code calls these. Pass --DLODEPNG_NO_COMPILE_ALLOCATORS to the compiler, or comment out -#define LODEPNG_COMPILE_ALLOCATORS in the header, to disable the ones here and -define them in your own project's source files without needing to change -lodepng source code. Don't forget to remove "static" if you copypaste them -from here.*/ - -#ifdef LODEPNG_COMPILE_ALLOCATORS -static void* lodepng_malloc(size_t size) { -#ifdef LODEPNG_MAX_ALLOC - if(size > LODEPNG_MAX_ALLOC) return 0; -#endif - return malloc(size); -} - -/* NOTE: when realloc returns NULL, it leaves the original memory untouched */ -static void* lodepng_realloc(void* ptr, size_t new_size) { -#ifdef LODEPNG_MAX_ALLOC - if(new_size > LODEPNG_MAX_ALLOC) return 0; -#endif - return realloc(ptr, new_size); -} - -static void lodepng_free(void* ptr) { - free(ptr); -} -#else /*LODEPNG_COMPILE_ALLOCATORS*/ -/* TODO: support giving additional void* payload to the custom allocators */ -void* lodepng_malloc(size_t size); -void* lodepng_realloc(void* ptr, size_t new_size); -void lodepng_free(void* ptr); -#endif /*LODEPNG_COMPILE_ALLOCATORS*/ - -/* convince the compiler to inline a function, for use when this measurably improves performance */ -/* inline is not available in C90, but use it when supported by the compiler */ -#if (defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)) || (defined(__cplusplus) && (__cplusplus >= 199711L)) -#define LODEPNG_INLINE inline -#else -#define LODEPNG_INLINE /* not available */ -#endif - -/* restrict is not available in C90, but use it when supported by the compiler */ -#if (defined(__GNUC__) && (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1))) ||\ - (defined(_MSC_VER) && (_MSC_VER >= 1400)) || \ - (defined(__WATCOMC__) && (__WATCOMC__ >= 1250) && !defined(__cplusplus)) -#define LODEPNG_RESTRICT __restrict -#else -#define LODEPNG_RESTRICT /* not available */ -#endif - -/* Replacements for C library functions such as memcpy and strlen, to support platforms -where a full C library is not available. The compiler can recognize them and compile -to something as fast. */ - -static void lodepng_memcpy(void* LODEPNG_RESTRICT dst, - const void* LODEPNG_RESTRICT src, size_t size) { - size_t i; - for(i = 0; i < size; i++) ((char*)dst)[i] = ((const char*)src)[i]; -} - -static void lodepng_memset(void* LODEPNG_RESTRICT dst, - int value, size_t num) { - size_t i; - for(i = 0; i < num; i++) ((char*)dst)[i] = (char)value; -} - -/* does not check memory out of bounds, do not use on untrusted data */ -static size_t lodepng_strlen(const char* a) { - const char* orig = a; - /* avoid warning about unused function in case of disabled COMPILE... macros */ - (void)(&lodepng_strlen); - while(*a) a++; - return (size_t)(a - orig); -} - -#define LODEPNG_MAX(a, b) (((a) > (b)) ? (a) : (b)) -#define LODEPNG_MIN(a, b) (((a) < (b)) ? (a) : (b)) - -#if defined(LODEPNG_COMPILE_PNG) || defined(LODEPNG_COMPILE_DECODER) -/* Safely check if adding two integers will overflow (no undefined -behavior, compiler removing the code, etc...) and output result. */ -static int lodepng_addofl(size_t a, size_t b, size_t* result) { - *result = a + b; /* Unsigned addition is well defined and safe in C90 */ - return *result < a; -} -#endif /*defined(LODEPNG_COMPILE_PNG) || defined(LODEPNG_COMPILE_DECODER)*/ - -#ifdef LODEPNG_COMPILE_DECODER -/* Safely check if multiplying two integers will overflow (no undefined -behavior, compiler removing the code, etc...) and output result. */ -static int lodepng_mulofl(size_t a, size_t b, size_t* result) { - *result = a * b; /* Unsigned multiplication is well defined and safe in C90 */ - return (a != 0 && *result / a != b); -} - -#ifdef LODEPNG_COMPILE_ZLIB -/* Safely check if a + b > c, even if overflow could happen. */ -static int lodepng_gtofl(size_t a, size_t b, size_t c) { - size_t d; - if(lodepng_addofl(a, b, &d)) return 1; - return d > c; -} -#endif /*LODEPNG_COMPILE_ZLIB*/ -#endif /*LODEPNG_COMPILE_DECODER*/ - - -/* -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_resize(&lz77_encoded, datasize)) ERROR_BREAK(83); -*/ -#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) - -/*Set error var to the error code, and return it.*/ -#define CERROR_RETURN_ERROR(errorvar, code){\ - errorvar = code;\ - return code;\ -} - -/*Try the code, if it returns error, also return the error.*/ -#define CERROR_TRY_RETURN(call){\ - unsigned error = call;\ - if(error) return error;\ -} - -/*Set error var to the error code, and return from the void function.*/ -#define CERROR_RETURN(errorvar, code){\ - errorvar = code;\ - return;\ -} - -/* -About uivector, ucvector and string: --All of them wrap dynamic arrays or text strings in a similar way. --LodePNG was originally written in C++. The vectors replace the std::vectors that were used in the C++ version. --The string tools are made to avoid problems with compilers that declare things like strncat as deprecated. --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 -/*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; - lodepng_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) { - size_t allocsize = size * sizeof(unsigned); - if(allocsize > p->allocsize) { - size_t newsize = allocsize + (p->allocsize >> 1u); - void* data = lodepng_realloc(p->data, newsize); - if(data) { - p->allocsize = newsize; - p->data = (unsigned*)data; - } - else return 0; /*error: not enough memory*/ - } - p->size = size; - return 1; /*success*/ -} - -static void uivector_init(uivector* p) { - p->data = NULL; - p->size = p->allocsize = 0; -} - -/*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; -} -#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; - -/*returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned ucvector_reserve(ucvector* p, size_t size) { - if(size > p->allocsize) { - size_t newsize = size + (p->allocsize >> 1u); - void* data = lodepng_realloc(p->data, newsize); - if(data) { - p->allocsize = newsize; - p->data = (unsigned char*)data; - } - else return 0; /*error: not enough memory*/ - } - return 1; /*success*/ -} - -/*returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned ucvector_resize(ucvector* p, size_t size) { - p->size = size; - return ucvector_reserve(p, size); -} - -static ucvector ucvector_init(unsigned char* buffer, size_t size) { - ucvector v; - v.data = buffer; - v.allocsize = v.size = size; - return v; -} - -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_PNG -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - -/*free string pointer and set it to NULL*/ -static void string_cleanup(char** out) { - lodepng_free(*out); - *out = NULL; -} - -/*also appends null termination character*/ -static char* alloc_string_sized(const char* in, size_t insize) { - char* out = (char*)lodepng_malloc(insize + 1); - if(out) { - lodepng_memcpy(out, in, insize); - out[insize] = 0; - } - return out; -} - -/* dynamically allocates a new string with a copy of the null terminated input text */ -static char* alloc_string(const char* in) { - return alloc_string_sized(in, lodepng_strlen(in)); -} -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -#endif /*LODEPNG_COMPILE_PNG*/ - -/* ////////////////////////////////////////////////////////////////////////// */ - -#if defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_PNG) -static unsigned lodepng_read32bitInt(const unsigned char* buffer) { - return (((unsigned)buffer[0] << 24u) | ((unsigned)buffer[1] << 16u) | - ((unsigned)buffer[2] << 8u) | (unsigned)buffer[3]); -} -#endif /*defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_PNG)*/ - -#if defined(LODEPNG_COMPILE_PNG) || defined(LODEPNG_COMPILE_ENCODER) -/*buffer must have at least 4 allocated bytes available*/ -static void lodepng_set32bitInt(unsigned char* buffer, unsigned value) { - buffer[0] = (unsigned char)((value >> 24) & 0xff); - buffer[1] = (unsigned char)((value >> 16) & 0xff); - buffer[2] = (unsigned char)((value >> 8) & 0xff); - buffer[3] = (unsigned char)((value ) & 0xff); -} -#endif /*defined(LODEPNG_COMPILE_PNG) || defined(LODEPNG_COMPILE_ENCODER)*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / File IO / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_DISK - -/* returns negative value on error. This should be pure C compatible, so no fstat. */ -static long lodepng_filesize(const char* filename) { - FILE* file; - long size; - file = fopen(filename, "rb"); - if(!file) return -1; - - if(fseek(file, 0, SEEK_END) != 0) { - fclose(file); - return -1; - } - - size = ftell(file); - /* It may give LONG_MAX as directory size, this is invalid for us. */ - if(size == LONG_MAX) size = -1; - - fclose(file); - return size; -} - -/* load file into buffer that already has the correct allocated size. Returns error code.*/ -static unsigned lodepng_buffer_file(unsigned char* out, size_t size, const char* filename) { - FILE* file; - size_t readsize; - file = fopen(filename, "rb"); - if(!file) return 78; - - readsize = fread(out, 1, size, file); - fclose(file); - - if(readsize != size) return 78; - return 0; -} - -unsigned lodepng_load_file(unsigned char** out, size_t* outsize, const char* filename) { - long size = lodepng_filesize(filename); - if(size < 0) return 78; - *outsize = (size_t)size; - - *out = (unsigned char*)lodepng_malloc((size_t)size); - if(!(*out) && size > 0) return 83; /*the above malloc failed*/ - - return lodepng_buffer_file(*out, (size_t)size, filename); -} - -/*write given buffer to the file, overwriting the file, it doesn't append to it.*/ -unsigned lodepng_save_file(const unsigned char* buffer, size_t buffersize, const char* filename) { - FILE* file; - file = fopen(filename, "wb" ); - if(!file) return 79; - fwrite(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 -#ifdef LODEPNG_COMPILE_ENCODER - -typedef struct { - ucvector* data; - unsigned char bp; /*ok to overflow, indicates bit pos inside byte*/ -} LodePNGBitWriter; - -static void LodePNGBitWriter_init(LodePNGBitWriter* writer, ucvector* data) { - writer->data = data; - writer->bp = 0; -} - -/*TODO: this ignores potential out of memory errors*/ -#define WRITEBIT(writer, bit){\ - /* append new byte */\ - if(((writer->bp) & 7u) == 0) {\ - if(!ucvector_resize(writer->data, writer->data->size + 1)) return;\ - writer->data->data[writer->data->size - 1] = 0;\ - }\ - (writer->data->data[writer->data->size - 1]) |= (bit << ((writer->bp) & 7u));\ - ++writer->bp;\ -} - -/* LSB of value is written first, and LSB of bytes is used first */ -static void writeBits(LodePNGBitWriter* writer, unsigned value, size_t nbits) { - if(nbits == 1) { /* compiler should statically compile this case if nbits == 1 */ - WRITEBIT(writer, value); - } else { - /* TODO: increase output size only once here rather than in each WRITEBIT */ - size_t i; - for(i = 0; i != nbits; ++i) { - WRITEBIT(writer, (unsigned char)((value >> i) & 1)); - } - } -} - -/* This one is to use for adding huffman symbol, the value bits are written MSB first */ -static void writeBitsReversed(LodePNGBitWriter* writer, unsigned value, size_t nbits) { - size_t i; - for(i = 0; i != nbits; ++i) { - /* TODO: increase output size only once here rather than in each WRITEBIT */ - WRITEBIT(writer, (unsigned char)((value >> (nbits - 1u - i)) & 1u)); - } -} -#endif /*LODEPNG_COMPILE_ENCODER*/ - -#ifdef LODEPNG_COMPILE_DECODER - -typedef struct { - const unsigned char* data; - size_t size; /*size of data in bytes*/ - size_t bitsize; /*size of data in bits, end of valid bp values, should be 8*size*/ - size_t bp; - unsigned buffer; /*buffer for reading bits. NOTE: 'unsigned' must support at least 32 bits*/ -} LodePNGBitReader; - -/* data size argument is in bytes. Returns error if size too large causing overflow */ -static unsigned LodePNGBitReader_init(LodePNGBitReader* reader, const unsigned char* data, size_t size) { - size_t temp; - reader->data = data; - reader->size = size; - /* size in bits, return error if overflow (if size_t is 32 bit this supports up to 500MB) */ - if(lodepng_mulofl(size, 8u, &reader->bitsize)) return 105; - /*ensure incremented bp can be compared to bitsize without overflow even when it would be incremented 32 too much and - trying to ensure 32 more bits*/ - if(lodepng_addofl(reader->bitsize, 64u, &temp)) return 105; - reader->bp = 0; - reader->buffer = 0; - return 0; /*ok*/ -} - -/* -ensureBits functions: -Ensures the reader can at least read nbits bits in one or more readBits calls, -safely even if not enough bits are available. -The nbits parameter is unused but is given for documentation purposes, error -checking for amount of bits must be done beforehand. -*/ - -/*See ensureBits documentation above. This one ensures up to 9 bits */ -static LODEPNG_INLINE void ensureBits9(LodePNGBitReader* reader, size_t nbits) { - size_t start = reader->bp >> 3u; - size_t size = reader->size; - if(start + 1u < size) { - reader->buffer = (unsigned)reader->data[start + 0] | ((unsigned)reader->data[start + 1] << 8u); - reader->buffer >>= (reader->bp & 7u); - } else { - reader->buffer = 0; - if(start + 0u < size) reader->buffer = reader->data[start + 0]; - reader->buffer >>= (reader->bp & 7u); - } - (void)nbits; -} - -/*See ensureBits documentation above. This one ensures up to 17 bits */ -static LODEPNG_INLINE void ensureBits17(LodePNGBitReader* reader, size_t nbits) { - size_t start = reader->bp >> 3u; - size_t size = reader->size; - if(start + 2u < size) { - reader->buffer = (unsigned)reader->data[start + 0] | ((unsigned)reader->data[start + 1] << 8u) | - ((unsigned)reader->data[start + 2] << 16u); - reader->buffer >>= (reader->bp & 7u); - } else { - reader->buffer = 0; - if(start + 0u < size) reader->buffer |= reader->data[start + 0]; - if(start + 1u < size) reader->buffer |= ((unsigned)reader->data[start + 1] << 8u); - reader->buffer >>= (reader->bp & 7u); - } - (void)nbits; -} - -/*See ensureBits documentation above. This one ensures up to 25 bits */ -static LODEPNG_INLINE void ensureBits25(LodePNGBitReader* reader, size_t nbits) { - size_t start = reader->bp >> 3u; - size_t size = reader->size; - if(start + 3u < size) { - reader->buffer = (unsigned)reader->data[start + 0] | ((unsigned)reader->data[start + 1] << 8u) | - ((unsigned)reader->data[start + 2] << 16u) | ((unsigned)reader->data[start + 3] << 24u); - reader->buffer >>= (reader->bp & 7u); - } else { - reader->buffer = 0; - if(start + 0u < size) reader->buffer |= reader->data[start + 0]; - if(start + 1u < size) reader->buffer |= ((unsigned)reader->data[start + 1] << 8u); - if(start + 2u < size) reader->buffer |= ((unsigned)reader->data[start + 2] << 16u); - reader->buffer >>= (reader->bp & 7u); - } - (void)nbits; -} - -/*See ensureBits documentation above. This one ensures up to 32 bits */ -static LODEPNG_INLINE void ensureBits32(LodePNGBitReader* reader, size_t nbits) { - size_t start = reader->bp >> 3u; - size_t size = reader->size; - if(start + 4u < size) { - reader->buffer = (unsigned)reader->data[start + 0] | ((unsigned)reader->data[start + 1] << 8u) | - ((unsigned)reader->data[start + 2] << 16u) | ((unsigned)reader->data[start + 3] << 24u); - reader->buffer >>= (reader->bp & 7u); - reader->buffer |= (((unsigned)reader->data[start + 4] << 24u) << (8u - (reader->bp & 7u))); - } else { - reader->buffer = 0; - if(start + 0u < size) reader->buffer |= reader->data[start + 0]; - if(start + 1u < size) reader->buffer |= ((unsigned)reader->data[start + 1] << 8u); - if(start + 2u < size) reader->buffer |= ((unsigned)reader->data[start + 2] << 16u); - if(start + 3u < size) reader->buffer |= ((unsigned)reader->data[start + 3] << 24u); - reader->buffer >>= (reader->bp & 7u); - } - (void)nbits; -} - -/* Get bits without advancing the bit pointer. Must have enough bits available with ensureBits. Max nbits is 31. */ -static LODEPNG_INLINE unsigned peekBits(LodePNGBitReader* reader, size_t nbits) { - /* The shift allows nbits to be only up to 31. */ - return reader->buffer & ((1u << nbits) - 1u); -} - -/* Must have enough bits available with ensureBits */ -static LODEPNG_INLINE void advanceBits(LodePNGBitReader* reader, size_t nbits) { - reader->buffer >>= nbits; - reader->bp += nbits; -} - -/* Must have enough bits available with ensureBits */ -static LODEPNG_INLINE unsigned readBits(LodePNGBitReader* reader, size_t nbits) { - unsigned result = peekBits(reader, nbits); - advanceBits(reader, nbits); - return result; -} -#endif /*LODEPNG_COMPILE_DECODER*/ - -static unsigned reverseBits(unsigned bits, unsigned num) { - /*TODO: implement faster lookup table based version when needed*/ - unsigned i, result = 0; - for(i = 0; i < num; i++) result |= ((bits >> (num - i - 1u)) & 1u) << i; - return result; -} - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / 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 as specified by deflate, 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 { - unsigned* codes; /*the huffman codes (bit patterns representing the symbols)*/ - unsigned* lengths; /*the lengths of the huffman codes*/ - unsigned maxbitlen; /*maximum number of bits a single code can get*/ - unsigned numcodes; /*number of symbols in the alphabet = number of codes*/ - /* for reading only */ - unsigned char* table_len; /*length of symbol from lookup table, or max length if secondary lookup needed*/ - unsigned short* table_value; /*value of symbol from lookup table, or pointer to secondary table if needed*/ -} HuffmanTree; - -static void HuffmanTree_init(HuffmanTree* tree) { - tree->codes = 0; - tree->lengths = 0; - tree->table_len = 0; - tree->table_value = 0; -} - -static void HuffmanTree_cleanup(HuffmanTree* tree) { - lodepng_free(tree->codes); - lodepng_free(tree->lengths); - lodepng_free(tree->table_len); - lodepng_free(tree->table_value); -} - -/* amount of bits for first huffman table lookup (aka root bits), see HuffmanTree_makeTable and huffmanDecodeSymbol.*/ -/* values 8u and 9u work the fastest */ -#define FIRSTBITS 9u - -/* a symbol value too big to represent any valid symbol, to indicate reading disallowed huffman bits combination, -which is possible in case of only 0 or 1 present symbols. */ -#define INVALIDSYMBOL 65535u - -/* make table for huffman decoding */ -static unsigned HuffmanTree_makeTable(HuffmanTree* tree) { - static const unsigned headsize = 1u << FIRSTBITS; /*size of the first table*/ - static const unsigned mask = (1u << FIRSTBITS) /*headsize*/ - 1u; - size_t i, numpresent, pointer, size; /*total table size*/ - unsigned* maxlens = (unsigned*)lodepng_malloc(headsize * sizeof(unsigned)); - if(!maxlens) return 83; /*alloc fail*/ - - /* compute maxlens: max total bit length of symbols sharing prefix in the first table*/ - lodepng_memset(maxlens, 0, headsize * sizeof(*maxlens)); - for(i = 0; i < tree->numcodes; i++) { - unsigned symbol = tree->codes[i]; - unsigned l = tree->lengths[i]; - unsigned index; - if(l <= FIRSTBITS) continue; /*symbols that fit in first table don't increase secondary table size*/ - /*get the FIRSTBITS MSBs, the MSBs of the symbol are encoded first. See later comment about the reversing*/ - index = reverseBits(symbol >> (l - FIRSTBITS), FIRSTBITS); - maxlens[index] = LODEPNG_MAX(maxlens[index], l); - } - /* compute total table size: size of first table plus all secondary tables for symbols longer than FIRSTBITS */ - size = headsize; - for(i = 0; i < headsize; ++i) { - unsigned l = maxlens[i]; - if(l > FIRSTBITS) size += (1u << (l - FIRSTBITS)); - } - tree->table_len = (unsigned char*)lodepng_malloc(size * sizeof(*tree->table_len)); - tree->table_value = (unsigned short*)lodepng_malloc(size * sizeof(*tree->table_value)); - if(!tree->table_len || !tree->table_value) { - lodepng_free(maxlens); - /* freeing tree->table values is done at a higher scope */ - return 83; /*alloc fail*/ - } - /*initialize with an invalid length to indicate unused entries*/ - for(i = 0; i < size; ++i) tree->table_len[i] = 16; - - /*fill in the first table for long symbols: max prefix size and pointer to secondary tables*/ - pointer = headsize; - for(i = 0; i < headsize; ++i) { - unsigned l = maxlens[i]; - if(l <= FIRSTBITS) continue; - tree->table_len[i] = l; - tree->table_value[i] = pointer; - pointer += (1u << (l - FIRSTBITS)); - } - lodepng_free(maxlens); - - /*fill in the first table for short symbols, or secondary table for long symbols*/ - numpresent = 0; - for(i = 0; i < tree->numcodes; ++i) { - unsigned l = tree->lengths[i]; - unsigned symbol, reverse; - if(l == 0) continue; - symbol = tree->codes[i]; /*the huffman bit pattern. i itself is the value.*/ - /*reverse bits, because the huffman bits are given in MSB first order but the bit reader reads LSB first*/ - reverse = reverseBits(symbol, l); - numpresent++; - - if(l <= FIRSTBITS) { - /*short symbol, fully in first table, replicated num times if l < FIRSTBITS*/ - unsigned num = 1u << (FIRSTBITS - l); - unsigned j; - for(j = 0; j < num; ++j) { - /*bit reader will read the l bits of symbol first, the remaining FIRSTBITS - l bits go to the MSB's*/ - unsigned index = reverse | (j << l); - if(tree->table_len[index] != 16) return 55; /*invalid tree: long symbol shares prefix with short symbol*/ - tree->table_len[index] = l; - tree->table_value[index] = i; - } - } else { - /*long symbol, shares prefix with other long symbols in first lookup table, needs second lookup*/ - /*the FIRSTBITS MSBs of the symbol are the first table index*/ - unsigned index = reverse & mask; - unsigned maxlen = tree->table_len[index]; - /*log2 of secondary table length, should be >= l - FIRSTBITS*/ - unsigned tablelen = maxlen - FIRSTBITS; - unsigned start = tree->table_value[index]; /*starting index in secondary table*/ - unsigned num = 1u << (tablelen - (l - FIRSTBITS)); /*amount of entries of this symbol in secondary table*/ - unsigned j; - if(maxlen < l) return 55; /*invalid tree: long symbol shares prefix with short symbol*/ - for(j = 0; j < num; ++j) { - unsigned reverse2 = reverse >> FIRSTBITS; /* l - FIRSTBITS bits */ - unsigned index2 = start + (reverse2 | (j << (l - FIRSTBITS))); - tree->table_len[index2] = l; - tree->table_value[index2] = i; - } - } - } - - if(numpresent < 2) { - /* In case of exactly 1 symbol, in theory the huffman symbol needs 0 bits, - but deflate uses 1 bit instead. In case of 0 symbols, no symbols can - appear at all, but such huffman tree could still exist (e.g. if distance - codes are never used). In both cases, not all symbols of the table will be - filled in. Fill them in with an invalid symbol value so returning them from - huffmanDecodeSymbol will cause error. */ - for(i = 0; i < size; ++i) { - if(tree->table_len[i] == 16) { - /* As length, use a value smaller than FIRSTBITS for the head table, - and a value larger than FIRSTBITS for the secondary table, to ensure - valid behavior for advanceBits when reading this symbol. */ - tree->table_len[i] = (i < headsize) ? 1 : (FIRSTBITS + 1); - tree->table_value[i] = INVALIDSYMBOL; - } - } - } else { - /* A good huffman tree has N * 2 - 1 nodes, of which N - 1 are internal nodes. - If that is not the case (due to too long length codes), the table will not - have been fully used, and this is an error (not all bit combinations can be - decoded): an oversubscribed huffman tree, indicated by error 55. */ - for(i = 0; i < size; ++i) { - if(tree->table_len[i] == 16) return 55; - } - } - - 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) { - unsigned* blcount; - unsigned* nextcode; - unsigned error = 0; - unsigned bits, n; - - tree->codes = (unsigned*)lodepng_malloc(tree->numcodes * sizeof(unsigned)); - blcount = (unsigned*)lodepng_malloc((tree->maxbitlen + 1) * sizeof(unsigned)); - nextcode = (unsigned*)lodepng_malloc((tree->maxbitlen + 1) * sizeof(unsigned)); - if(!tree->codes || !blcount || !nextcode) error = 83; /*alloc fail*/ - - if(!error) { - for(n = 0; n != tree->maxbitlen + 1; n++) blcount[n] = nextcode[n] = 0; - /*step 1: count number of instances of each code length*/ - for(bits = 0; bits != tree->numcodes; ++bits) ++blcount[tree->lengths[bits]]; - /*step 2: generate the nextcode values*/ - for(bits = 1; bits <= tree->maxbitlen; ++bits) { - nextcode[bits] = (nextcode[bits - 1] + blcount[bits - 1]) << 1u; - } - /*step 3: generate all the codes*/ - for(n = 0; n != tree->numcodes; ++n) { - if(tree->lengths[n] != 0) { - tree->codes[n] = nextcode[tree->lengths[n]]++; - /*remove superfluous bits from the code*/ - tree->codes[n] &= ((1u << tree->lengths[n]) - 1u); - } - } - } - - lodepng_free(blcount); - lodepng_free(nextcode); - - if(!error) error = HuffmanTree_makeTable(tree); - 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; - tree->lengths = (unsigned*)lodepng_malloc(numcodes * sizeof(unsigned)); - if(!tree->lengths) return 83; /*alloc fail*/ - for(i = 0; i != numcodes; ++i) tree->lengths[i] = bitlen[i]; - tree->numcodes = (unsigned)numcodes; /*number of symbols*/ - tree->maxbitlen = maxbitlen; - return HuffmanTree_makeFromLengths2(tree); -} - -#ifdef LODEPNG_COMPILE_ENCODER - -/*BPM: Boundary Package Merge, see "A Fast and Space-Economical Algorithm for Length-Limited Coding", -Jyrki Katajainen, Alistair Moffat, Andrew Turpin, 1995.*/ - -/*chain node for boundary package merge*/ -typedef struct BPMNode { - int weight; /*the sum of all weights in this chain*/ - unsigned index; /*index of this leaf node (called "count" in the paper)*/ - struct BPMNode* tail; /*the next nodes in this chain (null if last)*/ - int in_use; -} BPMNode; - -/*lists of chains*/ -typedef struct BPMLists { - /*memory pool*/ - unsigned memsize; - BPMNode* memory; - unsigned numfree; - unsigned nextfree; - BPMNode** freelist; - /*two heads of lookahead chains per list*/ - unsigned listsize; - BPMNode** chains0; - BPMNode** chains1; -} BPMLists; - -/*creates a new chain node with the given parameters, from the memory in the lists */ -static BPMNode* bpmnode_create(BPMLists* lists, int weight, unsigned index, BPMNode* tail) { - unsigned i; - BPMNode* result; - - /*memory full, so garbage collect*/ - if(lists->nextfree >= lists->numfree) { - /*mark only those that are in use*/ - for(i = 0; i != lists->memsize; ++i) lists->memory[i].in_use = 0; - for(i = 0; i != lists->listsize; ++i) { - BPMNode* node; - for(node = lists->chains0[i]; node != 0; node = node->tail) node->in_use = 1; - for(node = lists->chains1[i]; node != 0; node = node->tail) node->in_use = 1; - } - /*collect those that are free*/ - lists->numfree = 0; - for(i = 0; i != lists->memsize; ++i) { - if(!lists->memory[i].in_use) lists->freelist[lists->numfree++] = &lists->memory[i]; - } - lists->nextfree = 0; - } - - result = lists->freelist[lists->nextfree++]; - result->weight = weight; - result->index = index; - result->tail = tail; - return result; -} - -/*sort the leaves with stable mergesort*/ -static void bpmnode_sort(BPMNode* leaves, size_t num) { - BPMNode* mem = (BPMNode*)lodepng_malloc(sizeof(*leaves) * num); - size_t width, counter = 0; - for(width = 1; width < num; width *= 2) { - BPMNode* a = (counter & 1) ? mem : leaves; - BPMNode* b = (counter & 1) ? leaves : mem; - size_t p; - for(p = 0; p < num; p += 2 * width) { - size_t q = (p + width > num) ? num : (p + width); - size_t r = (p + 2 * width > num) ? num : (p + 2 * width); - size_t i = p, j = q, k; - for(k = p; k < r; k++) { - if(i < q && (j >= r || a[i].weight <= a[j].weight)) b[k] = a[i++]; - else b[k] = a[j++]; - } - } - counter++; - } - if(counter & 1) lodepng_memcpy(leaves, mem, sizeof(*leaves) * num); - lodepng_free(mem); -} - -/*Boundary Package Merge step, numpresent is the amount of leaves, and c is the current chain.*/ -static void boundaryPM(BPMLists* lists, BPMNode* leaves, size_t numpresent, int c, int num) { - unsigned lastindex = lists->chains1[c]->index; - - if(c == 0) { - if(lastindex >= numpresent) return; - lists->chains0[c] = lists->chains1[c]; - lists->chains1[c] = bpmnode_create(lists, leaves[lastindex].weight, lastindex + 1, 0); - } else { - /*sum of the weights of the head nodes of the previous lookahead chains.*/ - int sum = lists->chains0[c - 1]->weight + lists->chains1[c - 1]->weight; - lists->chains0[c] = lists->chains1[c]; - if(lastindex < numpresent && sum > leaves[lastindex].weight) { - lists->chains1[c] = bpmnode_create(lists, leaves[lastindex].weight, lastindex + 1, lists->chains1[c]->tail); - return; - } - lists->chains1[c] = bpmnode_create(lists, sum, lastindex, lists->chains1[c - 1]); - /*in the end we are only interested in the chain of the last list, so no - need to recurse if we're at the last one (this gives measurable speedup)*/ - if(num + 1 < (int)(2 * numpresent - 2)) { - boundaryPM(lists, leaves, numpresent, c - 1, num); - boundaryPM(lists, leaves, numpresent, c - 1, num); - } - } -} - -unsigned lodepng_huffman_code_lengths(unsigned* lengths, const unsigned* frequencies, - size_t numcodes, unsigned maxbitlen) { - unsigned error = 0; - unsigned i; - size_t numpresent = 0; /*number of symbols with non-zero frequency*/ - BPMNode* leaves; /*the symbols, only those with > 0 frequency*/ - - if(numcodes == 0) return 80; /*error: a tree of 0 symbols is not supposed to be made*/ - if((1u << maxbitlen) < (unsigned)numcodes) return 80; /*error: represent all symbols*/ - - leaves = (BPMNode*)lodepng_malloc(numcodes * sizeof(*leaves)); - if(!leaves) return 83; /*alloc fail*/ - - for(i = 0; i != numcodes; ++i) { - if(frequencies[i] > 0) { - leaves[numpresent].weight = (int)frequencies[i]; - leaves[numpresent].index = i; - ++numpresent; - } - } - - lodepng_memset(lengths, 0, numcodes * sizeof(*lengths)); - - /*ensure at least two present symbols. There should be at least one symbol - according to RFC 1951 section 3.2.7. Some decoders incorrectly require two. To - make these work as well ensure there are at least two symbols. The - Package-Merge code below also doesn't work correctly if there's only one - symbol, it'd give it the theoretical 0 bits but in practice zlib wants 1 bit*/ - if(numpresent == 0) { - lengths[0] = lengths[1] = 1; /*note that for RFC 1951 section 3.2.7, only lengths[0] = 1 is needed*/ - } else if(numpresent == 1) { - lengths[leaves[0].index] = 1; - lengths[leaves[0].index == 0 ? 1 : 0] = 1; - } else { - BPMLists lists; - BPMNode* node; - - bpmnode_sort(leaves, numpresent); - - lists.listsize = maxbitlen; - lists.memsize = 2 * maxbitlen * (maxbitlen + 1); - lists.nextfree = 0; - lists.numfree = lists.memsize; - lists.memory = (BPMNode*)lodepng_malloc(lists.memsize * sizeof(*lists.memory)); - lists.freelist = (BPMNode**)lodepng_malloc(lists.memsize * sizeof(BPMNode*)); - lists.chains0 = (BPMNode**)lodepng_malloc(lists.listsize * sizeof(BPMNode*)); - lists.chains1 = (BPMNode**)lodepng_malloc(lists.listsize * sizeof(BPMNode*)); - if(!lists.memory || !lists.freelist || !lists.chains0 || !lists.chains1) error = 83; /*alloc fail*/ - - if(!error) { - for(i = 0; i != lists.memsize; ++i) lists.freelist[i] = &lists.memory[i]; - - bpmnode_create(&lists, leaves[0].weight, 1, 0); - bpmnode_create(&lists, leaves[1].weight, 2, 0); - - for(i = 0; i != lists.listsize; ++i) { - lists.chains0[i] = &lists.memory[0]; - lists.chains1[i] = &lists.memory[1]; - } - - /*each boundaryPM call adds one chain to the last list, and we need 2 * numpresent - 2 chains.*/ - for(i = 2; i != 2 * numpresent - 2; ++i) boundaryPM(&lists, leaves, numpresent, (int)maxbitlen - 1, (int)i); - - for(node = lists.chains1[maxbitlen - 1]; node; node = node->tail) { - for(i = 0; i != node->index; ++i) ++lengths[leaves[i].index]; - } - } - - lodepng_free(lists.memory); - lodepng_free(lists.freelist); - lodepng_free(lists.chains0); - lodepng_free(lists.chains1); - } - - lodepng_free(leaves); - return error; -} - -/*Create the Huffman tree given the symbol frequencies*/ -static unsigned HuffmanTree_makeFromFrequencies(HuffmanTree* tree, const unsigned* frequencies, - size_t mincodes, size_t numcodes, unsigned maxbitlen) { - unsigned error = 0; - while(!frequencies[numcodes - 1] && numcodes > mincodes) --numcodes; /*trim zeroes*/ - tree->lengths = (unsigned*)lodepng_malloc(numcodes * sizeof(unsigned)); - if(!tree->lengths) return 83; /*alloc fail*/ - tree->maxbitlen = maxbitlen; - tree->numcodes = (unsigned)numcodes; /*number of symbols*/ - - error = lodepng_huffman_code_lengths(tree->lengths, frequencies, numcodes, maxbitlen); - if(!error) error = HuffmanTree_makeFromLengths2(tree); - return error; -} -#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; - unsigned* bitlen = (unsigned*)lodepng_malloc(NUM_DEFLATE_CODE_SYMBOLS * sizeof(unsigned)); - if(!bitlen) return 83; /*alloc fail*/ - - /*288 possible codes: 0-255=literals, 256=endcode, 257-285=lengthcodes, 286-287=unused*/ - for(i = 0; i <= 143; ++i) bitlen[i] = 8; - for(i = 144; i <= 255; ++i) bitlen[i] = 9; - for(i = 256; i <= 279; ++i) bitlen[i] = 7; - for(i = 280; i <= 287; ++i) bitlen[i] = 8; - - error = HuffmanTree_makeFromLengths(tree, bitlen, NUM_DEFLATE_CODE_SYMBOLS, 15); - - lodepng_free(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; - unsigned* bitlen = (unsigned*)lodepng_malloc(NUM_DISTANCE_SYMBOLS * sizeof(unsigned)); - if(!bitlen) return 83; /*alloc fail*/ - - /*there are 32 distance codes, but 30-31 are unused*/ - for(i = 0; i != NUM_DISTANCE_SYMBOLS; ++i) bitlen[i] = 5; - error = HuffmanTree_makeFromLengths(tree, bitlen, NUM_DISTANCE_SYMBOLS, 15); - - lodepng_free(bitlen); - return error; -} - -#ifdef LODEPNG_COMPILE_DECODER - -/* -returns the code. The bit reader must already have been ensured at least 15 bits -*/ -static unsigned huffmanDecodeSymbol(LodePNGBitReader* reader, const HuffmanTree* codetree) { - unsigned short code = peekBits(reader, FIRSTBITS); - unsigned short l = codetree->table_len[code]; - unsigned short value = codetree->table_value[code]; - if(l <= FIRSTBITS) { - advanceBits(reader, l); - return value; - } else { - advanceBits(reader, FIRSTBITS); - value += peekBits(reader, l - FIRSTBITS); - advanceBits(reader, codetree->table_len[value] - FIRSTBITS); - return codetree->table_value[value]; - } -} -#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 -Returns error code.*/ -static unsigned getTreeInflateFixed(HuffmanTree* tree_ll, HuffmanTree* tree_d) { - unsigned error = generateFixedLitLenTree(tree_ll); - if(error) return error; - return 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, - LodePNGBitReader* reader) { - /*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; - - /*see comments in deflateDynamic for explanation of the context and these variables, it is analogous*/ - unsigned* bitlen_ll = 0; /*lit,len code lengths*/ - unsigned* bitlen_d = 0; /*dist code lengths*/ - /*code length code lengths ("clcl"), the bit lengths of the huffman tree used to compress bitlen_ll and bitlen_d*/ - unsigned* bitlen_cl = 0; - HuffmanTree tree_cl; /*the code tree for code length codes (the huffman tree for compressed huffman trees)*/ - - if(reader->bitsize - reader->bp < 14) return 49; /*error: the bit pointer is or will go past the memory*/ - ensureBits17(reader, 14); - - /*number of literal/length codes + 257. Unlike the spec, the value 257 is added to it here already*/ - HLIT = readBits(reader, 5) + 257; - /*number of distance codes. Unlike the spec, the value 1 is added to it here already*/ - HDIST = readBits(reader, 5) + 1; - /*number of code length codes. Unlike the spec, the value 4 is added to it here already*/ - HCLEN = readBits(reader, 4) + 4; - - bitlen_cl = (unsigned*)lodepng_malloc(NUM_CODE_LENGTH_CODES * sizeof(unsigned)); - if(!bitlen_cl) return 83 /*alloc fail*/; - - HuffmanTree_init(&tree_cl); - - while(!error) { - /*read the code length codes out of 3 * (amount of code length codes) bits*/ - if(lodepng_gtofl(reader->bp, HCLEN * 3, reader->bitsize)) { - ERROR_BREAK(50); /*error: the bit pointer is or will go past the memory*/ - } - for(i = 0; i != HCLEN; ++i) { - ensureBits9(reader, 3); /*out of bounds already checked above */ - bitlen_cl[CLCL_ORDER[i]] = readBits(reader, 3); - } - for(i = HCLEN; i != NUM_CODE_LENGTH_CODES; ++i) { - bitlen_cl[CLCL_ORDER[i]] = 0; - } - - error = HuffmanTree_makeFromLengths(&tree_cl, bitlen_cl, NUM_CODE_LENGTH_CODES, 7); - if(error) break; - - /*now we can use this tree to read the lengths for the tree that this function will return*/ - bitlen_ll = (unsigned*)lodepng_malloc(NUM_DEFLATE_CODE_SYMBOLS * sizeof(unsigned)); - bitlen_d = (unsigned*)lodepng_malloc(NUM_DISTANCE_SYMBOLS * sizeof(unsigned)); - if(!bitlen_ll || !bitlen_d) ERROR_BREAK(83 /*alloc fail*/); - lodepng_memset(bitlen_ll, 0, NUM_DEFLATE_CODE_SYMBOLS * sizeof(*bitlen_ll)); - lodepng_memset(bitlen_d, 0, NUM_DISTANCE_SYMBOLS * sizeof(*bitlen_d)); - - /*i is the current symbol we're reading in the part that contains the code lengths of lit/len and dist codes*/ - i = 0; - while(i < HLIT + HDIST) { - unsigned code; - ensureBits25(reader, 22); /* up to 15 bits for huffman code, up to 7 extra bits below*/ - code = huffmanDecodeSymbol(reader, &tree_cl); - if(code <= 15) /*a length code*/ { - if(i < HLIT) bitlen_ll[i] = code; - else bitlen_d[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(i == 0) ERROR_BREAK(54); /*can't repeat previous if i is 0*/ - - replength += readBits(reader, 2); - - if(i < HLIT + 1) value = bitlen_ll[i - 1]; - else value = bitlen_d[i - HLIT - 1]; - /*repeat this value in the next lengths*/ - for(n = 0; n < replength; ++n) { - if(i >= HLIT + HDIST) ERROR_BREAK(13); /*error: i is larger than the amount of codes*/ - if(i < HLIT) bitlen_ll[i] = value; - else bitlen_d[i - HLIT] = value; - ++i; - } - } else if(code == 17) /*repeat "0" 3-10 times*/ { - unsigned replength = 3; /*read in the bits that indicate repeat length*/ - replength += readBits(reader, 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[i] = 0; - else bitlen_d[i - HLIT] = 0; - ++i; - } - } else if(code == 18) /*repeat "0" 11-138 times*/ { - unsigned replength = 11; /*read in the bits that indicate repeat length*/ - replength += readBits(reader, 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[i] = 0; - else bitlen_d[i - HLIT] = 0; - ++i; - } - } else /*if(code == INVALIDSYMBOL)*/ { - ERROR_BREAK(16); /*error: tried to read disallowed huffman symbol*/ - } - /*check if any of the ensureBits above went out of bounds*/ - if(reader->bp > reader->bitsize) { - /*return error code 10 or 11 depending on the situation that happened in huffmanDecodeSymbol - (10=no endcode, 11=wrong jump outside of tree)*/ - /* TODO: revise error codes 10,11,50: the above comment is no longer valid */ - ERROR_BREAK(50); /*error, bit pointer jumps past memory*/ - } - } - if(error) break; - - if(bitlen_ll[256] == 0) ERROR_BREAK(64); /*the length of the end code 256 must be larger than 0*/ - - /*now we've finally got HLIT and HDIST, so generate the code trees, and the function is done*/ - error = HuffmanTree_makeFromLengths(tree_ll, bitlen_ll, NUM_DEFLATE_CODE_SYMBOLS, 15); - if(error) break; - error = HuffmanTree_makeFromLengths(tree_d, bitlen_d, NUM_DISTANCE_SYMBOLS, 15); - - break; /*end of error-while*/ - } - - lodepng_free(bitlen_cl); - lodepng_free(bitlen_ll); - lodepng_free(bitlen_d); - HuffmanTree_cleanup(&tree_cl); - - return error; -} - -/*inflate a block with dynamic of fixed Huffman tree. btype must be 1 or 2.*/ -static unsigned inflateHuffmanBlock(ucvector* out, LodePNGBitReader* reader, - unsigned btype, size_t max_output_size) { - unsigned error = 0; - HuffmanTree tree_ll; /*the huffman tree for literal and length codes*/ - HuffmanTree tree_d; /*the huffman tree for distance codes*/ - const size_t reserved_size = 260; /* must be at least 258 for max length, and a few extra for adding a few extra literals */ - int done = 0; - - if(!ucvector_reserve(out, out->size + reserved_size)) return 83; /*alloc fail*/ - - HuffmanTree_init(&tree_ll); - HuffmanTree_init(&tree_d); - - if(btype == 1) error = getTreeInflateFixed(&tree_ll, &tree_d); - else /*if(btype == 2)*/ error = getTreeInflateDynamic(&tree_ll, &tree_d, reader); - - - while(!error && !done) /*decode all symbols until end reached, breaks at end code*/ { - /*code_ll is literal, length or end code*/ - unsigned code_ll; - /* ensure enough bits for 2 huffman code reads (15 bits each): if the first is a literal, a second literal is read at once. This - appears to be slightly faster, than ensuring 20 bits here for 1 huffman symbol and the potential 5 extra bits for the length symbol.*/ - ensureBits32(reader, 30); - code_ll = huffmanDecodeSymbol(reader, &tree_ll); - if(code_ll <= 255) { - /*slightly faster code path if multiple literals in a row*/ - out->data[out->size++] = (unsigned char)code_ll; - code_ll = huffmanDecodeSymbol(reader, &tree_ll); - } - if(code_ll <= 255) /*literal symbol*/ { - out->data[out->size++] = (unsigned char)code_ll; - } 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, 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(numextrabits_l != 0) { - /* bits already ensured above */ - ensureBits25(reader, 5); - length += readBits(reader, numextrabits_l); - } - - /*part 3: get distance code*/ - ensureBits32(reader, 28); /* up to 15 for the huffman symbol, up to 13 for the extra bits */ - code_d = huffmanDecodeSymbol(reader, &tree_d); - if(code_d > 29) { - if(code_d <= 31) { - ERROR_BREAK(18); /*error: invalid distance code (30-31 are never used)*/ - } else /* if(code_d == INVALIDSYMBOL) */{ - ERROR_BREAK(16); /*error: tried to read disallowed huffman symbol*/ - } - } - distance = DISTANCEBASE[code_d]; - - /*part 4: get extra bits from distance*/ - numextrabits_d = DISTANCEEXTRA[code_d]; - if(numextrabits_d != 0) { - /* bits already ensured above */ - distance += readBits(reader, numextrabits_d); - } - - /*part 5: fill in all the out[n] values based on the length and dist*/ - start = out->size; - if(distance > start) ERROR_BREAK(52); /*too long backward distance*/ - backward = start - distance; - - out->size += length; - if(distance < length) { - size_t forward; - lodepng_memcpy(out->data + start, out->data + backward, distance); - start += distance; - for(forward = distance; forward < length; ++forward) { - out->data[start++] = out->data[backward++]; - } - } else { - lodepng_memcpy(out->data + start, out->data + backward, length); - } - } else if(code_ll == 256) { - done = 1; /*end code, finish the loop*/ - } else /*if(code_ll == INVALIDSYMBOL)*/ { - ERROR_BREAK(16); /*error: tried to read disallowed huffman symbol*/ - } - if(out->allocsize - out->size < reserved_size) { - if(!ucvector_reserve(out, out->size + reserved_size)) ERROR_BREAK(83); /*alloc fail*/ - } - /*check if any of the ensureBits above went out of bounds*/ - if(reader->bp > reader->bitsize) { - /*return error code 10 or 11 depending on the situation that happened in huffmanDecodeSymbol - (10=no endcode, 11=wrong jump outside of tree)*/ - /* TODO: revise error codes 10,11,50: the above comment is no longer valid */ - ERROR_BREAK(51); /*error, bit pointer jumps past memory*/ - } - if(max_output_size && out->size > max_output_size) { - ERROR_BREAK(109); /*error, larger than max size*/ - } - } - - HuffmanTree_cleanup(&tree_ll); - HuffmanTree_cleanup(&tree_d); - - return error; -} - -static unsigned inflateNoCompression(ucvector* out, LodePNGBitReader* reader, - const LodePNGDecompressSettings* settings) { - size_t bytepos; - size_t size = reader->size; - unsigned LEN, NLEN, error = 0; - - /*go to first boundary of byte*/ - bytepos = (reader->bp + 7u) >> 3u; - - /*read LEN (2 bytes) and NLEN (2 bytes)*/ - if(bytepos + 4 >= size) return 52; /*error, bit pointer will jump past memory*/ - LEN = (unsigned)reader->data[bytepos] + ((unsigned)reader->data[bytepos + 1] << 8u); bytepos += 2; - NLEN = (unsigned)reader->data[bytepos] + ((unsigned)reader->data[bytepos + 1] << 8u); bytepos += 2; - - /*check if 16-bit NLEN is really the one's complement of LEN*/ - if(!settings->ignore_nlen && LEN + NLEN != 65535) { - return 21; /*error: NLEN is not one's complement of LEN*/ - } - - if(!ucvector_resize(out, out->size + LEN)) return 83; /*alloc fail*/ - - /*read the literal data: LEN bytes are now stored in the out buffer*/ - if(bytepos + LEN > size) return 23; /*error: reading outside of in buffer*/ - - /*out->data can be NULL (when LEN is zero), and arithmetics on NULL ptr is undefined*/ - if (LEN) { - lodepng_memcpy(out->data + out->size - LEN, reader->data + bytepos, LEN); - bytepos += LEN; - } - - reader->bp = bytepos << 3u; - - return error; -} - -static unsigned lodepng_inflatev(ucvector* out, - const unsigned char* in, size_t insize, - const LodePNGDecompressSettings* settings) { - unsigned BFINAL = 0; - LodePNGBitReader reader; - unsigned error = LodePNGBitReader_init(&reader, in, insize); - - if(error) return error; - - while(!BFINAL) { - unsigned BTYPE; - if(reader.bitsize - reader.bp < 3) return 52; /*error, bit pointer will jump past memory*/ - ensureBits9(&reader, 3); - BFINAL = readBits(&reader, 1); - BTYPE = readBits(&reader, 2); - - if(BTYPE == 3) return 20; /*error: invalid BTYPE*/ - else if(BTYPE == 0) error = inflateNoCompression(out, &reader, settings); /*no compression*/ - else error = inflateHuffmanBlock(out, &reader, BTYPE, settings->max_output_size); /*compression, BTYPE 01 or 10*/ - if(!error && settings->max_output_size && out->size > settings->max_output_size) error = 109; - if(error) break; - } - - return error; -} - -unsigned lodepng_inflate(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGDecompressSettings* settings) { - ucvector v = ucvector_init(*out, *outsize); - unsigned error = lodepng_inflatev(&v, in, insize, settings); - *out = v.data; - *outsize = v.size; - return error; -} - -static unsigned inflatev(ucvector* out, const unsigned char* in, size_t insize, - const LodePNGDecompressSettings* settings) { - if(settings->custom_inflate) { - unsigned error = settings->custom_inflate(&out->data, &out->size, in, insize, settings); - out->allocsize = out->size; - if(error) { - /*the custom inflate is allowed to have its own error codes, however, we translate it to code 110*/ - error = 110; - /*if there's a max output size, and the custom zlib returned error, then indicate that error instead*/ - if(settings->max_output_size && out->size > settings->max_output_size) error = 109; - } - return error; - } else { - return lodepng_inflatev(out, in, insize, settings); - } -} - -#endif /*LODEPNG_COMPILE_DECODER*/ - -#ifdef LODEPNG_COMPILE_ENCODER - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Deflator (Compressor) / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -static const size_t MAX_SUPPORTED_DEFLATE_LENGTH = 258; - -/*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) { - /*binary search (only small gain over linear). TODO: use CPU log2 instruction for getting symbols instead*/ - size_t left = 1; - size_t right = array_size - 1; - - while(left <= right) { - size_t mid = (left + right) >> 1; - if(array[mid] >= value) right = mid - 1; - else left = mid + 1; - } - if(left >= array_size || array[left] > value) left--; - return left; -} - -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]); - - size_t pos = values->size; - /*TODO: return error when this fails (out of memory)*/ - unsigned ok = uivector_resize(values, values->size + 4); - if(ok) { - values->data[pos + 0] = length_code + FIRST_LENGTH_CODE_INDEX; - values->data[pos + 1] = extra_length; - values->data[pos + 2] = dist_code; - values->data[pos + 3] = extra_distance; - } -} - -/*3 bytes of data get encoded into two bytes. The hash cannot use more than 3 -bytes as input because 3 is the minimum match length for deflate*/ -static const unsigned HASH_NUM_VALUES = 65536; -static const unsigned HASH_BIT_MASK = 65535; /*HASH_NUM_VALUES - 1, but C90 does not like that as initializer*/ - -typedef struct Hash { - int* head; /*hash value to head circular pos - can be outdated if went around window*/ - /*circular pos to prev circular pos*/ - unsigned short* chain; - int* val; /*circular pos to hash value*/ - - /*TODO: do this not only for zeros but for any repeated byte. However for PNG - it's always going to be the zeros that dominate, so not important for PNG*/ - int* headz; /*similar to head, but for chainz*/ - unsigned short* chainz; /*those with same amount of zeros*/ - unsigned short* zeros; /*length of zeros streak, used as a second hash chain*/ -} Hash; - -static unsigned hash_init(Hash* hash, unsigned windowsize) { - unsigned i; - hash->head = (int*)lodepng_malloc(sizeof(int) * HASH_NUM_VALUES); - hash->val = (int*)lodepng_malloc(sizeof(int) * windowsize); - hash->chain = (unsigned short*)lodepng_malloc(sizeof(unsigned short) * windowsize); - - hash->zeros = (unsigned short*)lodepng_malloc(sizeof(unsigned short) * windowsize); - hash->headz = (int*)lodepng_malloc(sizeof(int) * (MAX_SUPPORTED_DEFLATE_LENGTH + 1)); - hash->chainz = (unsigned short*)lodepng_malloc(sizeof(unsigned short) * windowsize); - - if(!hash->head || !hash->chain || !hash->val || !hash->headz|| !hash->chainz || !hash->zeros) { - return 83; /*alloc fail*/ - } - - /*initialize hash table*/ - for(i = 0; i != HASH_NUM_VALUES; ++i) hash->head[i] = -1; - for(i = 0; i != windowsize; ++i) hash->val[i] = -1; - for(i = 0; i != windowsize; ++i) hash->chain[i] = i; /*same value as index indicates uninitialized*/ - - for(i = 0; i <= MAX_SUPPORTED_DEFLATE_LENGTH; ++i) hash->headz[i] = -1; - for(i = 0; i != windowsize; ++i) hash->chainz[i] = i; /*same value as index indicates uninitialized*/ - - return 0; -} - -static void hash_cleanup(Hash* hash) { - lodepng_free(hash->head); - lodepng_free(hash->val); - lodepng_free(hash->chain); - - lodepng_free(hash->zeros); - lodepng_free(hash->headz); - lodepng_free(hash->chainz); -} - - - -static unsigned getHash(const unsigned char* data, size_t size, size_t pos) { - unsigned result = 0; - if(pos + 2 < size) { - /*A simple shift and xor hash is used. Since the data of PNGs is dominated - by zeroes due to the filters, a better hash does not have a significant - effect on speed in traversing the chain, and causes more time spend on - calculating the hash.*/ - result ^= ((unsigned)data[pos + 0] << 0u); - result ^= ((unsigned)data[pos + 1] << 4u); - result ^= ((unsigned)data[pos + 2] << 8u); - } else { - size_t amount, i; - if(pos >= size) return 0; - amount = size - pos; - for(i = 0; i != amount; ++i) result ^= ((unsigned)data[pos + i] << (i * 8u)); - } - return result & HASH_BIT_MASK; -} - -static unsigned countZeros(const unsigned char* data, size_t size, size_t pos) { - const unsigned char* start = data + pos; - const unsigned char* end = start + MAX_SUPPORTED_DEFLATE_LENGTH; - if(end > data + size) end = data + size; - data = start; - while(data != end && *data == 0) ++data; - /*subtracting two addresses returned as 32-bit number (max value is MAX_SUPPORTED_DEFLATE_LENGTH)*/ - return (unsigned)(data - start); -} - -/*wpos = pos & (windowsize - 1)*/ -static void updateHashChain(Hash* hash, size_t wpos, unsigned hashval, unsigned short numzeros) { - hash->val[wpos] = (int)hashval; - if(hash->head[hashval] != -1) hash->chain[wpos] = hash->head[hashval]; - hash->head[hashval] = (int)wpos; - - hash->zeros[wpos] = numzeros; - if(hash->headz[numzeros] != -1) hash->chainz[wpos] = hash->headz[numzeros]; - hash->headz[numzeros] = (int)wpos; -} - -/* -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, Hash* hash, - const unsigned char* in, size_t inpos, size_t insize, unsigned windowsize, - unsigned minmatch, unsigned nicematch, unsigned lazymatching) { - size_t pos; - unsigned i, error = 0; - /*for large window lengths, assume the user wants no compression loss. Otherwise, max hash chain length speedup.*/ - unsigned maxchainlength = windowsize >= 8192 ? windowsize : windowsize / 8u; - unsigned maxlazymatch = windowsize >= 8192 ? MAX_SUPPORTED_DEFLATE_LENGTH : 64; - - unsigned usezeros = 1; /*not sure if setting it to false for windowsize < 8192 is better or worse*/ - unsigned numzeros = 0; - - unsigned offset; /*the offset represents the distance in LZ77 terminology*/ - unsigned length; - unsigned lazy = 0; - unsigned lazylength = 0, lazyoffset = 0; - unsigned hashval; - unsigned current_offset, current_length; - unsigned prev_offset; - const unsigned char *lastptr, *foreptr, *backptr; - unsigned hashpos; - - if(windowsize == 0 || windowsize > 32768) return 60; /*error: windowsize smaller/larger than allowed*/ - if((windowsize & (windowsize - 1)) != 0) return 90; /*error: must be power of two*/ - - if(nicematch > MAX_SUPPORTED_DEFLATE_LENGTH) nicematch = MAX_SUPPORTED_DEFLATE_LENGTH; - - for(pos = inpos; pos < insize; ++pos) { - size_t wpos = pos & (windowsize - 1); /*position for in 'circular' hash buffers*/ - unsigned chainlength = 0; - - hashval = getHash(in, insize, pos); - - if(usezeros && hashval == 0) { - if(numzeros == 0) numzeros = countZeros(in, insize, pos); - else if(pos + numzeros > insize || in[pos + numzeros - 1] != 0) --numzeros; - } else { - numzeros = 0; - } - - updateHashChain(hash, wpos, hashval, numzeros); - - /*the length and offset found for the current position*/ - length = 0; - offset = 0; - - hashpos = hash->chain[wpos]; - - lastptr = &in[insize < pos + MAX_SUPPORTED_DEFLATE_LENGTH ? insize : pos + MAX_SUPPORTED_DEFLATE_LENGTH]; - - /*search for the longest string*/ - prev_offset = 0; - for(;;) { - if(chainlength++ >= maxchainlength) break; - current_offset = (unsigned)(hashpos <= wpos ? wpos - hashpos : wpos - hashpos + windowsize); - - if(current_offset < prev_offset) break; /*stop when went completely around the circular buffer*/ - prev_offset = current_offset; - if(current_offset > 0) { - /*test the next characters*/ - foreptr = &in[pos]; - backptr = &in[pos - current_offset]; - - /*common case in PNGs is lots of zeros. Quickly skip over them as a speedup*/ - if(numzeros >= 3) { - unsigned skip = hash->zeros[hashpos]; - if(skip > numzeros) skip = numzeros; - 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*/ - /*jump out once a length of max length is found (speed gain). This also jumps - out if length is MAX_SUPPORTED_DEFLATE_LENGTH*/ - if(current_length >= nicematch) break; - } - } - - if(hashpos == hash->chain[hashpos]) break; - - if(numzeros >= 3 && length > numzeros) { - hashpos = hash->chainz[hashpos]; - if(hash->zeros[hashpos] != numzeros) break; - } else { - hashpos = hash->chain[hashpos]; - /*outdated hash value, happens if particular value was not encountered in whole last window*/ - if(hash->val[hashpos] != (int)hashval) break; - } - } - - if(lazymatching) { - if(!lazy && length >= 3 && length <= maxlazymatch && length < MAX_SUPPORTED_DEFLATE_LENGTH) { - lazy = 1; - lazylength = length; - lazyoffset = offset; - continue; /*try the next byte*/ - } - if(lazy) { - lazy = 0; - if(pos == 0) ERROR_BREAK(81); - if(length > lazylength + 1) { - /*push the previous character as literal*/ - if(!uivector_push_back(out, in[pos - 1])) ERROR_BREAK(83 /*alloc fail*/); - } else { - length = lazylength; - offset = lazyoffset; - hash->head[hashval] = -1; /*the same hashchain update will be done, this ensures no wrong alteration*/ - hash->headz[numzeros] = -1; /*idem*/ - --pos; - } - } - } - if(length >= 3 && offset > windowsize) ERROR_BREAK(86 /*too big (or overflown negative) offset*/); - - /*encode it as length/distance pair or literal value*/ - if(length < 3) /*only lengths of 3 or higher are supported as length/distance pair*/ { - if(!uivector_push_back(out, in[pos])) ERROR_BREAK(83 /*alloc fail*/); - } else if(length < minmatch || (length == 3 && offset > 4096)) { - /*compensate for the fact that longer offsets have more extra bits, a - length of only 3 may be not worth it then*/ - if(!uivector_push_back(out, in[pos])) ERROR_BREAK(83 /*alloc fail*/); - } else { - addLengthDistance(out, length, offset); - for(i = 1; i < length; ++i) { - ++pos; - wpos = pos & (windowsize - 1); - hashval = getHash(in, insize, pos); - if(usezeros && hashval == 0) { - if(numzeros == 0) numzeros = countZeros(in, insize, pos); - else if(pos + numzeros > insize || in[pos + numzeros - 1] != 0) --numzeros; - } else { - numzeros = 0; - } - updateHashChain(hash, wpos, hashval, numzeros); - } - } - } /*end of the loop through each character of input*/ - - 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, numdeflateblocks = (datasize + 65534u) / 65535u; - unsigned datapos = 0; - for(i = 0; i != numdeflateblocks; ++i) { - unsigned BFINAL, BTYPE, LEN, NLEN; - unsigned char firstbyte; - size_t pos = out->size; - - BFINAL = (i == numdeflateblocks - 1); - BTYPE = 0; - - LEN = 65535; - if(datasize - datapos < 65535u) LEN = (unsigned)datasize - datapos; - NLEN = 65535 - LEN; - - if(!ucvector_resize(out, out->size + LEN + 5)) return 83; /*alloc fail*/ - - firstbyte = (unsigned char)(BFINAL + ((BTYPE & 1u) << 1u) + ((BTYPE & 2u) << 1u)); - out->data[pos + 0] = firstbyte; - out->data[pos + 1] = (unsigned char)(LEN & 255); - out->data[pos + 2] = (unsigned char)(LEN >> 8u); - out->data[pos + 3] = (unsigned char)(NLEN & 255); - out->data[pos + 4] = (unsigned char)(NLEN >> 8u); - lodepng_memcpy(out->data + pos + 5, data + datapos, LEN); - datapos += LEN; - } - - 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(LodePNGBitWriter* writer, 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]; - writeBitsReversed(writer, tree_ll->codes[val], tree_ll->lengths[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]; - - writeBits(writer, length_extra_bits, n_length_extra_bits); - writeBitsReversed(writer, tree_d->codes[distance_code], tree_d->lengths[distance_code]); - writeBits(writer, 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(LodePNGBitWriter* writer, Hash* hash, - const unsigned char* data, size_t datapos, size_t dataend, - const LodePNGCompressSettings* settings, unsigned final) { - 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 lengths 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*/ - unsigned* frequencies_ll = 0; /*frequency of lit,len codes*/ - unsigned* frequencies_d = 0; /*frequency of dist codes*/ - unsigned* frequencies_cl = 0; /*frequency of code length codes*/ - unsigned* bitlen_lld = 0; /*lit,len,dist code lengths (int bits), literally (without repeat codes).*/ - unsigned* bitlen_lld_e = 0; /*bitlen_lld encoded with repeat codes (this is a rudimentary run length compression)*/ - size_t datasize = dataend - datapos; - - /* - If we could call "bitlen_cl" the the code length code lengths ("clcl"), that is the bit lengths of codes to represent - tree_cl in CLCL_ORDER, then due to the huffman compression of huffman tree representations ("two levels"), there are - some analogies: - 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 = final; - size_t i; - size_t numcodes_ll, numcodes_d, numcodes_lld, numcodes_lld_e, numcodes_cl; - unsigned HLIT, HDIST, HCLEN; - - uivector_init(&lz77_encoded); - HuffmanTree_init(&tree_ll); - HuffmanTree_init(&tree_d); - HuffmanTree_init(&tree_cl); - /* could fit on stack, but >1KB is on the larger side so allocate instead */ - frequencies_ll = (unsigned*)lodepng_malloc(286 * sizeof(*frequencies_ll)); - frequencies_d = (unsigned*)lodepng_malloc(30 * sizeof(*frequencies_d)); - frequencies_cl = (unsigned*)lodepng_malloc(NUM_CODE_LENGTH_CODES * sizeof(*frequencies_cl)); - - if(!frequencies_ll || !frequencies_d || !frequencies_cl) error = 83; /*alloc fail*/ - - /*This while loop never loops due to a break at the end, it is here to - allow breaking out of it to the cleanup phase on error conditions.*/ - while(!error) { - lodepng_memset(frequencies_ll, 0, 286 * sizeof(*frequencies_ll)); - lodepng_memset(frequencies_d, 0, 30 * sizeof(*frequencies_d)); - lodepng_memset(frequencies_cl, 0, NUM_CODE_LENGTH_CODES * sizeof(*frequencies_cl)); - - if(settings->use_lz77) { - error = encodeLZ77(&lz77_encoded, hash, data, datapos, dataend, settings->windowsize, - settings->minmatch, settings->nicematch, settings->lazymatching); - if(error) break; - } else { - if(!uivector_resize(&lz77_encoded, datasize)) ERROR_BREAK(83 /*alloc fail*/); - for(i = datapos; i < dataend; ++i) lz77_encoded.data[i - datapos] = data[i]; /*no LZ77, but still will be Huffman compressed*/ - } - - /*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[symbol]; - if(symbol > 256) { - unsigned dist = lz77_encoded.data[i + 2]; - ++frequencies_d[dist]; - i += 3; - } - } - frequencies_ll[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, 257, 286, 15); - if(error) break; - /*2, not 1, is chosen for mincodes: some buggy PNG decoders require at least 2 symbols in the dist tree*/ - error = HuffmanTree_makeFromFrequencies(&tree_d, frequencies_d, 2, 30, 15); - if(error) break; - - numcodes_ll = LODEPNG_MIN(tree_ll.numcodes, 286); - numcodes_d = LODEPNG_MIN(tree_d.numcodes, 30); - /*store the code lengths of both generated trees in bitlen_lld*/ - numcodes_lld = numcodes_ll + numcodes_d; - bitlen_lld = (unsigned*)lodepng_malloc(numcodes_lld * sizeof(*bitlen_lld)); - /*numcodes_lld_e never needs more size than bitlen_lld*/ - bitlen_lld_e = (unsigned*)lodepng_malloc(numcodes_lld * sizeof(*bitlen_lld_e)); - if(!bitlen_lld || !bitlen_lld_e) ERROR_BREAK(83); /*alloc fail*/ - numcodes_lld_e = 0; - - for(i = 0; i != numcodes_ll; ++i) bitlen_lld[i] = tree_ll.lengths[i]; - for(i = 0; i != numcodes_d; ++i) bitlen_lld[numcodes_ll + i] = tree_d.lengths[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 != numcodes_lld; ++i) { - unsigned j = 0; /*amount of repetitions*/ - while(i + j + 1 < numcodes_lld && bitlen_lld[i + j + 1] == bitlen_lld[i]) ++j; - - if(bitlen_lld[i] == 0 && j >= 2) /*repeat code for zeroes*/ { - ++j; /*include the first zero*/ - if(j <= 10) /*repeat code 17 supports max 10 zeroes*/ { - bitlen_lld_e[numcodes_lld_e++] = 17; - bitlen_lld_e[numcodes_lld_e++] = j - 3; - } else /*repeat code 18 supports max 138 zeroes*/ { - if(j > 138) j = 138; - bitlen_lld_e[numcodes_lld_e++] = 18; - bitlen_lld_e[numcodes_lld_e++] = j - 11; - } - i += (j - 1); - } else if(j >= 3) /*repeat code for value other than zero*/ { - size_t k; - unsigned num = j / 6u, rest = j % 6u; - bitlen_lld_e[numcodes_lld_e++] = bitlen_lld[i]; - for(k = 0; k < num; ++k) { - bitlen_lld_e[numcodes_lld_e++] = 16; - bitlen_lld_e[numcodes_lld_e++] = 6 - 3; - } - if(rest >= 3) { - bitlen_lld_e[numcodes_lld_e++] = 16; - bitlen_lld_e[numcodes_lld_e++] = rest - 3; - } - else j -= rest; - i += j; - } else /*too short to benefit from repeat code*/ { - bitlen_lld_e[numcodes_lld_e++] = bitlen_lld[i]; - } - } - - /*generate tree_cl, the huffmantree of huffmantrees*/ - for(i = 0; i != numcodes_lld_e; ++i) { - ++frequencies_cl[bitlen_lld_e[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[i] >= 16) ++i; - } - - error = HuffmanTree_makeFromFrequencies(&tree_cl, frequencies_cl, - NUM_CODE_LENGTH_CODES, NUM_CODE_LENGTH_CODES, 7); - if(error) break; - - /*compute amount of code-length-code-lengths to output*/ - numcodes_cl = NUM_CODE_LENGTH_CODES; - /*trim zeros at the end (using CLCL_ORDER), but minimum size must be 4 (see HCLEN below)*/ - while(numcodes_cl > 4u && tree_cl.lengths[CLCL_ORDER[numcodes_cl - 1u]] == 0) { - numcodes_cl--; - } - - /* - 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 lengths 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*/ - writeBits(writer, BFINAL, 1); - writeBits(writer, 0, 1); /*first bit of BTYPE "dynamic"*/ - writeBits(writer, 1, 1); /*second bit of BTYPE "dynamic"*/ - - /*write the HLIT, HDIST and HCLEN values*/ - /*all three sizes take trimmed ending zeroes into account, done either by HuffmanTree_makeFromFrequencies - or in the loop for numcodes_cl above, which saves space. */ - HLIT = (unsigned)(numcodes_ll - 257); - HDIST = (unsigned)(numcodes_d - 1); - HCLEN = (unsigned)(numcodes_cl - 4); - writeBits(writer, HLIT, 5); - writeBits(writer, HDIST, 5); - writeBits(writer, HCLEN, 4); - - /*write the code lengths of the code length alphabet ("bitlen_cl")*/ - for(i = 0; i != numcodes_cl; ++i) writeBits(writer, tree_cl.lengths[CLCL_ORDER[i]], 3); - - /*write the lengths of the lit/len AND the dist alphabet*/ - for(i = 0; i != numcodes_lld_e; ++i) { - writeBitsReversed(writer, tree_cl.codes[bitlen_lld_e[i]], tree_cl.lengths[bitlen_lld_e[i]]); - /*extra bits of repeat codes*/ - if(bitlen_lld_e[i] == 16) writeBits(writer, bitlen_lld_e[++i], 2); - else if(bitlen_lld_e[i] == 17) writeBits(writer, bitlen_lld_e[++i], 3); - else if(bitlen_lld_e[i] == 18) writeBits(writer, bitlen_lld_e[++i], 7); - } - - /*write the compressed data symbols*/ - writeLZ77data(writer, &lz77_encoded, &tree_ll, &tree_d); - /*error: the length of the end code 256 must be larger than 0*/ - if(tree_ll.lengths[256] == 0) ERROR_BREAK(64); - - /*write the end code*/ - writeBitsReversed(writer, tree_ll.codes[256], tree_ll.lengths[256]); - - break; /*end of error-while*/ - } - - /*cleanup*/ - uivector_cleanup(&lz77_encoded); - HuffmanTree_cleanup(&tree_ll); - HuffmanTree_cleanup(&tree_d); - HuffmanTree_cleanup(&tree_cl); - lodepng_free(frequencies_ll); - lodepng_free(frequencies_d); - lodepng_free(frequencies_cl); - lodepng_free(bitlen_lld); - lodepng_free(bitlen_lld_e); - - return error; -} - -static unsigned deflateFixed(LodePNGBitWriter* writer, Hash* hash, - const unsigned char* data, - size_t datapos, size_t dataend, - const LodePNGCompressSettings* settings, unsigned final) { - HuffmanTree tree_ll; /*tree for literal values and length codes*/ - HuffmanTree tree_d; /*tree for distance codes*/ - - unsigned BFINAL = final; - unsigned error = 0; - size_t i; - - HuffmanTree_init(&tree_ll); - HuffmanTree_init(&tree_d); - - error = generateFixedLitLenTree(&tree_ll); - if(!error) error = generateFixedDistanceTree(&tree_d); - - if(!error) { - writeBits(writer, BFINAL, 1); - writeBits(writer, 1, 1); /*first bit of BTYPE*/ - writeBits(writer, 0, 1); /*second bit of BTYPE*/ - - if(settings->use_lz77) /*LZ77 encoded*/ { - uivector lz77_encoded; - uivector_init(&lz77_encoded); - error = encodeLZ77(&lz77_encoded, hash, data, datapos, dataend, settings->windowsize, - settings->minmatch, settings->nicematch, settings->lazymatching); - if(!error) writeLZ77data(writer, &lz77_encoded, &tree_ll, &tree_d); - uivector_cleanup(&lz77_encoded); - } else /*no LZ77, but still will be Huffman compressed*/ { - for(i = datapos; i < dataend; ++i) { - writeBitsReversed(writer, tree_ll.codes[data[i]], tree_ll.lengths[data[i]]); - } - } - /*add END code*/ - if(!error) writeBitsReversed(writer,tree_ll.codes[256], tree_ll.lengths[256]); - } - - /*cleanup*/ - HuffmanTree_cleanup(&tree_ll); - HuffmanTree_cleanup(&tree_d); - - return error; -} - -static unsigned lodepng_deflatev(ucvector* out, const unsigned char* in, size_t insize, - const LodePNGCompressSettings* settings) { - unsigned error = 0; - size_t i, blocksize, numdeflateblocks; - Hash hash; - LodePNGBitWriter writer; - - LodePNGBitWriter_init(&writer, out); - - if(settings->btype > 2) return 61; - else if(settings->btype == 0) return deflateNoCompression(out, in, insize); - else if(settings->btype == 1) blocksize = insize; - else /*if(settings->btype == 2)*/ { - /*on PNGs, deflate blocks of 65-262k seem to give most dense encoding*/ - blocksize = insize / 8u + 8; - if(blocksize < 65536) blocksize = 65536; - if(blocksize > 262144) blocksize = 262144; - } - - numdeflateblocks = (insize + blocksize - 1) / blocksize; - if(numdeflateblocks == 0) numdeflateblocks = 1; - - error = hash_init(&hash, settings->windowsize); - - if(!error) { - for(i = 0; i != numdeflateblocks && !error; ++i) { - unsigned final = (i == numdeflateblocks - 1); - size_t start = i * blocksize; - size_t end = start + blocksize; - if(end > insize) end = insize; - - if(settings->btype == 1) error = deflateFixed(&writer, &hash, in, start, end, settings, final); - else if(settings->btype == 2) error = deflateDynamic(&writer, &hash, in, start, end, settings, final); - } - } - - hash_cleanup(&hash); - - return error; -} - -unsigned lodepng_deflate(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGCompressSettings* settings) { - ucvector v = ucvector_init(*out, *outsize); - unsigned error = lodepng_deflatev(&v, in, insize, settings); - *out = v.data; - *outsize = v.size; - return error; -} - -static unsigned deflate(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGCompressSettings* settings) { - if(settings->custom_deflate) { - unsigned error = settings->custom_deflate(out, outsize, in, insize, settings); - /*the custom deflate is allowed to have its own error codes, however, we translate it to code 111*/ - return error ? 111 : 0; - } else { - return lodepng_deflate(out, outsize, in, insize, settings); - } -} - -#endif /*LODEPNG_COMPILE_DECODER*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Adler32 / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -static unsigned update_adler32(unsigned adler, const unsigned char* data, unsigned len) { - unsigned s1 = adler & 0xffffu; - unsigned s2 = (adler >> 16u) & 0xffffu; - - while(len != 0u) { - unsigned i; - /*at least 5552 sums can be done before the sums overflow, saving a lot of module divisions*/ - unsigned amount = len > 5552u ? 5552u : len; - len -= amount; - for(i = 0; i != amount; ++i) { - s1 += (*data++); - s2 += s1; - } - s1 %= 65521u; - s2 %= 65521u; - } - - return (s2 << 16u) | s1; -} - -/*Return the adler32 of the bytes data[0..len-1]*/ -static unsigned adler32(const unsigned char* data, unsigned len) { - return update_adler32(1u, data, len); -} - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Zlib / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_DECODER - -static unsigned lodepng_zlib_decompressv(ucvector* out, - const unsigned char* in, size_t insize, - const LodePNGDecompressSettings* settings) { - unsigned error = 0; - unsigned CM, CINFO, FDICT; - - 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; - } - - error = inflatev(out, in + 2, insize - 2, settings); - if(error) return error; - - if(!settings->ignore_adler32) { - unsigned ADLER32 = lodepng_read32bitInt(&in[insize - 4]); - unsigned checksum = adler32(out->data, (unsigned)(out->size)); - if(checksum != ADLER32) return 58; /*error, adler checksum not correct, data must be corrupted*/ - } - - return 0; /*no error*/ -} - - -unsigned lodepng_zlib_decompress(unsigned char** out, size_t* outsize, const unsigned char* in, - size_t insize, const LodePNGDecompressSettings* settings) { - ucvector v = ucvector_init(*out, *outsize); - unsigned error = lodepng_zlib_decompressv(&v, in, insize, settings); - *out = v.data; - *outsize = v.size; - return error; -} - -/*expected_size is expected output size, to avoid intermediate allocations. Set to 0 if not known. */ -static unsigned zlib_decompress(unsigned char** out, size_t* outsize, size_t expected_size, - const unsigned char* in, size_t insize, const LodePNGDecompressSettings* settings) { - unsigned error; - if(settings->custom_zlib) { - error = settings->custom_zlib(out, outsize, in, insize, settings); - if(error) { - /*the custom zlib is allowed to have its own error codes, however, we translate it to code 110*/ - error = 110; - /*if there's a max output size, and the custom zlib returned error, then indicate that error instead*/ - if(settings->max_output_size && *outsize > settings->max_output_size) error = 109; - } - } else { - ucvector v = ucvector_init(*out, *outsize); - if(expected_size) { - /*reserve the memory to avoid intermediate reallocations*/ - ucvector_resize(&v, *outsize + expected_size); - v.size = *outsize; - } - error = lodepng_zlib_decompressv(&v, in, insize, settings); - *out = v.data; - *outsize = v.size; - } - return 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 LodePNGCompressSettings* settings) { - size_t i; - unsigned error; - unsigned char* deflatedata = 0; - size_t deflatesize = 0; - - error = deflate(&deflatedata, &deflatesize, in, insize, settings); - - *out = NULL; - *outsize = 0; - if(!error) { - *outsize = deflatesize + 6; - *out = (unsigned char*)lodepng_malloc(*outsize); - if(!*out) error = 83; /*alloc fail*/ - } - - if(!error) { - unsigned ADLER32 = adler32(in, (unsigned)insize); - /*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; - - (*out)[0] = (unsigned char)(CMFFLG >> 8); - (*out)[1] = (unsigned char)(CMFFLG & 255); - for(i = 0; i != deflatesize; ++i) (*out)[i + 2] = deflatedata[i]; - lodepng_set32bitInt(&(*out)[*outsize - 4], ADLER32); - } - - lodepng_free(deflatedata); - return error; -} - -/* compress using the default or custom zlib function */ -static unsigned zlib_compress(unsigned char** out, size_t* outsize, const unsigned char* in, - size_t insize, const LodePNGCompressSettings* settings) { - if(settings->custom_zlib) { - unsigned error = settings->custom_zlib(out, outsize, in, insize, settings); - /*the custom zlib is allowed to have its own error codes, however, we translate it to code 111*/ - return error ? 111 : 0; - } else { - return lodepng_zlib_compress(out, outsize, in, insize, settings); - } -} - -#endif /*LODEPNG_COMPILE_ENCODER*/ - -#else /*no LODEPNG_COMPILE_ZLIB*/ - -#ifdef LODEPNG_COMPILE_DECODER -static unsigned zlib_decompress(unsigned char** out, size_t* outsize, size_t expected_size, - const unsigned char* in, size_t insize, const LodePNGDecompressSettings* settings) { - if(!settings->custom_zlib) return 87; /*no custom zlib function provided */ - (void)expected_size; - return settings->custom_zlib(out, outsize, in, insize, settings); -} -#endif /*LODEPNG_COMPILE_DECODER*/ -#ifdef LODEPNG_COMPILE_ENCODER -static unsigned zlib_compress(unsigned char** out, size_t* outsize, const unsigned char* in, - size_t insize, const LodePNGCompressSettings* settings) { - if(!settings->custom_zlib) return 87; /*no custom zlib function provided */ - return settings->custom_zlib(out, outsize, in, insize, settings); -} -#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_compress_settings_init(LodePNGCompressSettings* settings) { - /*compress with dynamic huffman tree (not in the mathematical sense, just not the predefined one)*/ - settings->btype = 2; - settings->use_lz77 = 1; - settings->windowsize = DEFAULT_WINDOWSIZE; - settings->minmatch = 3; - settings->nicematch = 128; - settings->lazymatching = 1; - - settings->custom_zlib = 0; - settings->custom_deflate = 0; - settings->custom_context = 0; -} - -const LodePNGCompressSettings lodepng_default_compress_settings = {2, 1, DEFAULT_WINDOWSIZE, 3, 128, 1, 0, 0, 0}; - - -#endif /*LODEPNG_COMPILE_ENCODER*/ - -#ifdef LODEPNG_COMPILE_DECODER - -void lodepng_decompress_settings_init(LodePNGDecompressSettings* settings) { - settings->ignore_adler32 = 0; - settings->ignore_nlen = 0; - settings->max_output_size = 0; - - settings->custom_zlib = 0; - settings->custom_inflate = 0; - settings->custom_context = 0; -} - -const LodePNGDecompressSettings lodepng_default_decompress_settings = {0, 0, 0, 0, 0, 0}; - -#endif /*LODEPNG_COMPILE_DECODER*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* // End of Zlib related code. Begin of PNG related code. // */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_PNG - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / CRC32 / */ -/* ////////////////////////////////////////////////////////////////////////// */ - - -#ifdef LODEPNG_COMPILE_CRC - -static const unsigned lodepng_crc32_table0[256] = { - 0x00000000u, 0x77073096u, 0xee0e612cu, 0x990951bau, 0x076dc419u, 0x706af48fu, 0xe963a535u, 0x9e6495a3u, - 0x0edb8832u, 0x79dcb8a4u, 0xe0d5e91eu, 0x97d2d988u, 0x09b64c2bu, 0x7eb17cbdu, 0xe7b82d07u, 0x90bf1d91u, - 0x1db71064u, 0x6ab020f2u, 0xf3b97148u, 0x84be41deu, 0x1adad47du, 0x6ddde4ebu, 0xf4d4b551u, 0x83d385c7u, - 0x136c9856u, 0x646ba8c0u, 0xfd62f97au, 0x8a65c9ecu, 0x14015c4fu, 0x63066cd9u, 0xfa0f3d63u, 0x8d080df5u, - 0x3b6e20c8u, 0x4c69105eu, 0xd56041e4u, 0xa2677172u, 0x3c03e4d1u, 0x4b04d447u, 0xd20d85fdu, 0xa50ab56bu, - 0x35b5a8fau, 0x42b2986cu, 0xdbbbc9d6u, 0xacbcf940u, 0x32d86ce3u, 0x45df5c75u, 0xdcd60dcfu, 0xabd13d59u, - 0x26d930acu, 0x51de003au, 0xc8d75180u, 0xbfd06116u, 0x21b4f4b5u, 0x56b3c423u, 0xcfba9599u, 0xb8bda50fu, - 0x2802b89eu, 0x5f058808u, 0xc60cd9b2u, 0xb10be924u, 0x2f6f7c87u, 0x58684c11u, 0xc1611dabu, 0xb6662d3du, - 0x76dc4190u, 0x01db7106u, 0x98d220bcu, 0xefd5102au, 0x71b18589u, 0x06b6b51fu, 0x9fbfe4a5u, 0xe8b8d433u, - 0x7807c9a2u, 0x0f00f934u, 0x9609a88eu, 0xe10e9818u, 0x7f6a0dbbu, 0x086d3d2du, 0x91646c97u, 0xe6635c01u, - 0x6b6b51f4u, 0x1c6c6162u, 0x856530d8u, 0xf262004eu, 0x6c0695edu, 0x1b01a57bu, 0x8208f4c1u, 0xf50fc457u, - 0x65b0d9c6u, 0x12b7e950u, 0x8bbeb8eau, 0xfcb9887cu, 0x62dd1ddfu, 0x15da2d49u, 0x8cd37cf3u, 0xfbd44c65u, - 0x4db26158u, 0x3ab551ceu, 0xa3bc0074u, 0xd4bb30e2u, 0x4adfa541u, 0x3dd895d7u, 0xa4d1c46du, 0xd3d6f4fbu, - 0x4369e96au, 0x346ed9fcu, 0xad678846u, 0xda60b8d0u, 0x44042d73u, 0x33031de5u, 0xaa0a4c5fu, 0xdd0d7cc9u, - 0x5005713cu, 0x270241aau, 0xbe0b1010u, 0xc90c2086u, 0x5768b525u, 0x206f85b3u, 0xb966d409u, 0xce61e49fu, - 0x5edef90eu, 0x29d9c998u, 0xb0d09822u, 0xc7d7a8b4u, 0x59b33d17u, 0x2eb40d81u, 0xb7bd5c3bu, 0xc0ba6cadu, - 0xedb88320u, 0x9abfb3b6u, 0x03b6e20cu, 0x74b1d29au, 0xead54739u, 0x9dd277afu, 0x04db2615u, 0x73dc1683u, - 0xe3630b12u, 0x94643b84u, 0x0d6d6a3eu, 0x7a6a5aa8u, 0xe40ecf0bu, 0x9309ff9du, 0x0a00ae27u, 0x7d079eb1u, - 0xf00f9344u, 0x8708a3d2u, 0x1e01f268u, 0x6906c2feu, 0xf762575du, 0x806567cbu, 0x196c3671u, 0x6e6b06e7u, - 0xfed41b76u, 0x89d32be0u, 0x10da7a5au, 0x67dd4accu, 0xf9b9df6fu, 0x8ebeeff9u, 0x17b7be43u, 0x60b08ed5u, - 0xd6d6a3e8u, 0xa1d1937eu, 0x38d8c2c4u, 0x4fdff252u, 0xd1bb67f1u, 0xa6bc5767u, 0x3fb506ddu, 0x48b2364bu, - 0xd80d2bdau, 0xaf0a1b4cu, 0x36034af6u, 0x41047a60u, 0xdf60efc3u, 0xa867df55u, 0x316e8eefu, 0x4669be79u, - 0xcb61b38cu, 0xbc66831au, 0x256fd2a0u, 0x5268e236u, 0xcc0c7795u, 0xbb0b4703u, 0x220216b9u, 0x5505262fu, - 0xc5ba3bbeu, 0xb2bd0b28u, 0x2bb45a92u, 0x5cb36a04u, 0xc2d7ffa7u, 0xb5d0cf31u, 0x2cd99e8bu, 0x5bdeae1du, - 0x9b64c2b0u, 0xec63f226u, 0x756aa39cu, 0x026d930au, 0x9c0906a9u, 0xeb0e363fu, 0x72076785u, 0x05005713u, - 0x95bf4a82u, 0xe2b87a14u, 0x7bb12baeu, 0x0cb61b38u, 0x92d28e9bu, 0xe5d5be0du, 0x7cdcefb7u, 0x0bdbdf21u, - 0x86d3d2d4u, 0xf1d4e242u, 0x68ddb3f8u, 0x1fda836eu, 0x81be16cdu, 0xf6b9265bu, 0x6fb077e1u, 0x18b74777u, - 0x88085ae6u, 0xff0f6a70u, 0x66063bcau, 0x11010b5cu, 0x8f659effu, 0xf862ae69u, 0x616bffd3u, 0x166ccf45u, - 0xa00ae278u, 0xd70dd2eeu, 0x4e048354u, 0x3903b3c2u, 0xa7672661u, 0xd06016f7u, 0x4969474du, 0x3e6e77dbu, - 0xaed16a4au, 0xd9d65adcu, 0x40df0b66u, 0x37d83bf0u, 0xa9bcae53u, 0xdebb9ec5u, 0x47b2cf7fu, 0x30b5ffe9u, - 0xbdbdf21cu, 0xcabac28au, 0x53b39330u, 0x24b4a3a6u, 0xbad03605u, 0xcdd70693u, 0x54de5729u, 0x23d967bfu, - 0xb3667a2eu, 0xc4614ab8u, 0x5d681b02u, 0x2a6f2b94u, 0xb40bbe37u, 0xc30c8ea1u, 0x5a05df1bu, 0x2d02ef8du -}; - -static const unsigned lodepng_crc32_table1[256] = { - 0x00000000u, 0x191b3141u, 0x32366282u, 0x2b2d53c3u, 0x646cc504u, 0x7d77f445u, 0x565aa786u, 0x4f4196c7u, - 0xc8d98a08u, 0xd1c2bb49u, 0xfaefe88au, 0xe3f4d9cbu, 0xacb54f0cu, 0xb5ae7e4du, 0x9e832d8eu, 0x87981ccfu, - 0x4ac21251u, 0x53d92310u, 0x78f470d3u, 0x61ef4192u, 0x2eaed755u, 0x37b5e614u, 0x1c98b5d7u, 0x05838496u, - 0x821b9859u, 0x9b00a918u, 0xb02dfadbu, 0xa936cb9au, 0xe6775d5du, 0xff6c6c1cu, 0xd4413fdfu, 0xcd5a0e9eu, - 0x958424a2u, 0x8c9f15e3u, 0xa7b24620u, 0xbea97761u, 0xf1e8e1a6u, 0xe8f3d0e7u, 0xc3de8324u, 0xdac5b265u, - 0x5d5daeaau, 0x44469febu, 0x6f6bcc28u, 0x7670fd69u, 0x39316baeu, 0x202a5aefu, 0x0b07092cu, 0x121c386du, - 0xdf4636f3u, 0xc65d07b2u, 0xed705471u, 0xf46b6530u, 0xbb2af3f7u, 0xa231c2b6u, 0x891c9175u, 0x9007a034u, - 0x179fbcfbu, 0x0e848dbau, 0x25a9de79u, 0x3cb2ef38u, 0x73f379ffu, 0x6ae848beu, 0x41c51b7du, 0x58de2a3cu, - 0xf0794f05u, 0xe9627e44u, 0xc24f2d87u, 0xdb541cc6u, 0x94158a01u, 0x8d0ebb40u, 0xa623e883u, 0xbf38d9c2u, - 0x38a0c50du, 0x21bbf44cu, 0x0a96a78fu, 0x138d96ceu, 0x5ccc0009u, 0x45d73148u, 0x6efa628bu, 0x77e153cau, - 0xbabb5d54u, 0xa3a06c15u, 0x888d3fd6u, 0x91960e97u, 0xded79850u, 0xc7cca911u, 0xece1fad2u, 0xf5facb93u, - 0x7262d75cu, 0x6b79e61du, 0x4054b5deu, 0x594f849fu, 0x160e1258u, 0x0f152319u, 0x243870dau, 0x3d23419bu, - 0x65fd6ba7u, 0x7ce65ae6u, 0x57cb0925u, 0x4ed03864u, 0x0191aea3u, 0x188a9fe2u, 0x33a7cc21u, 0x2abcfd60u, - 0xad24e1afu, 0xb43fd0eeu, 0x9f12832du, 0x8609b26cu, 0xc94824abu, 0xd05315eau, 0xfb7e4629u, 0xe2657768u, - 0x2f3f79f6u, 0x362448b7u, 0x1d091b74u, 0x04122a35u, 0x4b53bcf2u, 0x52488db3u, 0x7965de70u, 0x607eef31u, - 0xe7e6f3feu, 0xfefdc2bfu, 0xd5d0917cu, 0xcccba03du, 0x838a36fau, 0x9a9107bbu, 0xb1bc5478u, 0xa8a76539u, - 0x3b83984bu, 0x2298a90au, 0x09b5fac9u, 0x10aecb88u, 0x5fef5d4fu, 0x46f46c0eu, 0x6dd93fcdu, 0x74c20e8cu, - 0xf35a1243u, 0xea412302u, 0xc16c70c1u, 0xd8774180u, 0x9736d747u, 0x8e2de606u, 0xa500b5c5u, 0xbc1b8484u, - 0x71418a1au, 0x685abb5bu, 0x4377e898u, 0x5a6cd9d9u, 0x152d4f1eu, 0x0c367e5fu, 0x271b2d9cu, 0x3e001cddu, - 0xb9980012u, 0xa0833153u, 0x8bae6290u, 0x92b553d1u, 0xddf4c516u, 0xc4eff457u, 0xefc2a794u, 0xf6d996d5u, - 0xae07bce9u, 0xb71c8da8u, 0x9c31de6bu, 0x852aef2au, 0xca6b79edu, 0xd37048acu, 0xf85d1b6fu, 0xe1462a2eu, - 0x66de36e1u, 0x7fc507a0u, 0x54e85463u, 0x4df36522u, 0x02b2f3e5u, 0x1ba9c2a4u, 0x30849167u, 0x299fa026u, - 0xe4c5aeb8u, 0xfdde9ff9u, 0xd6f3cc3au, 0xcfe8fd7bu, 0x80a96bbcu, 0x99b25afdu, 0xb29f093eu, 0xab84387fu, - 0x2c1c24b0u, 0x350715f1u, 0x1e2a4632u, 0x07317773u, 0x4870e1b4u, 0x516bd0f5u, 0x7a468336u, 0x635db277u, - 0xcbfad74eu, 0xd2e1e60fu, 0xf9ccb5ccu, 0xe0d7848du, 0xaf96124au, 0xb68d230bu, 0x9da070c8u, 0x84bb4189u, - 0x03235d46u, 0x1a386c07u, 0x31153fc4u, 0x280e0e85u, 0x674f9842u, 0x7e54a903u, 0x5579fac0u, 0x4c62cb81u, - 0x8138c51fu, 0x9823f45eu, 0xb30ea79du, 0xaa1596dcu, 0xe554001bu, 0xfc4f315au, 0xd7626299u, 0xce7953d8u, - 0x49e14f17u, 0x50fa7e56u, 0x7bd72d95u, 0x62cc1cd4u, 0x2d8d8a13u, 0x3496bb52u, 0x1fbbe891u, 0x06a0d9d0u, - 0x5e7ef3ecu, 0x4765c2adu, 0x6c48916eu, 0x7553a02fu, 0x3a1236e8u, 0x230907a9u, 0x0824546au, 0x113f652bu, - 0x96a779e4u, 0x8fbc48a5u, 0xa4911b66u, 0xbd8a2a27u, 0xf2cbbce0u, 0xebd08da1u, 0xc0fdde62u, 0xd9e6ef23u, - 0x14bce1bdu, 0x0da7d0fcu, 0x268a833fu, 0x3f91b27eu, 0x70d024b9u, 0x69cb15f8u, 0x42e6463bu, 0x5bfd777au, - 0xdc656bb5u, 0xc57e5af4u, 0xee530937u, 0xf7483876u, 0xb809aeb1u, 0xa1129ff0u, 0x8a3fcc33u, 0x9324fd72u -}; - -static const unsigned lodepng_crc32_table2[256] = { - 0x00000000u, 0x01c26a37u, 0x0384d46eu, 0x0246be59u, 0x0709a8dcu, 0x06cbc2ebu, 0x048d7cb2u, 0x054f1685u, - 0x0e1351b8u, 0x0fd13b8fu, 0x0d9785d6u, 0x0c55efe1u, 0x091af964u, 0x08d89353u, 0x0a9e2d0au, 0x0b5c473du, - 0x1c26a370u, 0x1de4c947u, 0x1fa2771eu, 0x1e601d29u, 0x1b2f0bacu, 0x1aed619bu, 0x18abdfc2u, 0x1969b5f5u, - 0x1235f2c8u, 0x13f798ffu, 0x11b126a6u, 0x10734c91u, 0x153c5a14u, 0x14fe3023u, 0x16b88e7au, 0x177ae44du, - 0x384d46e0u, 0x398f2cd7u, 0x3bc9928eu, 0x3a0bf8b9u, 0x3f44ee3cu, 0x3e86840bu, 0x3cc03a52u, 0x3d025065u, - 0x365e1758u, 0x379c7d6fu, 0x35dac336u, 0x3418a901u, 0x3157bf84u, 0x3095d5b3u, 0x32d36beau, 0x331101ddu, - 0x246be590u, 0x25a98fa7u, 0x27ef31feu, 0x262d5bc9u, 0x23624d4cu, 0x22a0277bu, 0x20e69922u, 0x2124f315u, - 0x2a78b428u, 0x2bbade1fu, 0x29fc6046u, 0x283e0a71u, 0x2d711cf4u, 0x2cb376c3u, 0x2ef5c89au, 0x2f37a2adu, - 0x709a8dc0u, 0x7158e7f7u, 0x731e59aeu, 0x72dc3399u, 0x7793251cu, 0x76514f2bu, 0x7417f172u, 0x75d59b45u, - 0x7e89dc78u, 0x7f4bb64fu, 0x7d0d0816u, 0x7ccf6221u, 0x798074a4u, 0x78421e93u, 0x7a04a0cau, 0x7bc6cafdu, - 0x6cbc2eb0u, 0x6d7e4487u, 0x6f38fadeu, 0x6efa90e9u, 0x6bb5866cu, 0x6a77ec5bu, 0x68315202u, 0x69f33835u, - 0x62af7f08u, 0x636d153fu, 0x612bab66u, 0x60e9c151u, 0x65a6d7d4u, 0x6464bde3u, 0x662203bau, 0x67e0698du, - 0x48d7cb20u, 0x4915a117u, 0x4b531f4eu, 0x4a917579u, 0x4fde63fcu, 0x4e1c09cbu, 0x4c5ab792u, 0x4d98dda5u, - 0x46c49a98u, 0x4706f0afu, 0x45404ef6u, 0x448224c1u, 0x41cd3244u, 0x400f5873u, 0x4249e62au, 0x438b8c1du, - 0x54f16850u, 0x55330267u, 0x5775bc3eu, 0x56b7d609u, 0x53f8c08cu, 0x523aaabbu, 0x507c14e2u, 0x51be7ed5u, - 0x5ae239e8u, 0x5b2053dfu, 0x5966ed86u, 0x58a487b1u, 0x5deb9134u, 0x5c29fb03u, 0x5e6f455au, 0x5fad2f6du, - 0xe1351b80u, 0xe0f771b7u, 0xe2b1cfeeu, 0xe373a5d9u, 0xe63cb35cu, 0xe7fed96bu, 0xe5b86732u, 0xe47a0d05u, - 0xef264a38u, 0xeee4200fu, 0xeca29e56u, 0xed60f461u, 0xe82fe2e4u, 0xe9ed88d3u, 0xebab368au, 0xea695cbdu, - 0xfd13b8f0u, 0xfcd1d2c7u, 0xfe976c9eu, 0xff5506a9u, 0xfa1a102cu, 0xfbd87a1bu, 0xf99ec442u, 0xf85cae75u, - 0xf300e948u, 0xf2c2837fu, 0xf0843d26u, 0xf1465711u, 0xf4094194u, 0xf5cb2ba3u, 0xf78d95fau, 0xf64fffcdu, - 0xd9785d60u, 0xd8ba3757u, 0xdafc890eu, 0xdb3ee339u, 0xde71f5bcu, 0xdfb39f8bu, 0xddf521d2u, 0xdc374be5u, - 0xd76b0cd8u, 0xd6a966efu, 0xd4efd8b6u, 0xd52db281u, 0xd062a404u, 0xd1a0ce33u, 0xd3e6706au, 0xd2241a5du, - 0xc55efe10u, 0xc49c9427u, 0xc6da2a7eu, 0xc7184049u, 0xc25756ccu, 0xc3953cfbu, 0xc1d382a2u, 0xc011e895u, - 0xcb4dafa8u, 0xca8fc59fu, 0xc8c97bc6u, 0xc90b11f1u, 0xcc440774u, 0xcd866d43u, 0xcfc0d31au, 0xce02b92du, - 0x91af9640u, 0x906dfc77u, 0x922b422eu, 0x93e92819u, 0x96a63e9cu, 0x976454abu, 0x9522eaf2u, 0x94e080c5u, - 0x9fbcc7f8u, 0x9e7eadcfu, 0x9c381396u, 0x9dfa79a1u, 0x98b56f24u, 0x99770513u, 0x9b31bb4au, 0x9af3d17du, - 0x8d893530u, 0x8c4b5f07u, 0x8e0de15eu, 0x8fcf8b69u, 0x8a809decu, 0x8b42f7dbu, 0x89044982u, 0x88c623b5u, - 0x839a6488u, 0x82580ebfu, 0x801eb0e6u, 0x81dcdad1u, 0x8493cc54u, 0x8551a663u, 0x8717183au, 0x86d5720du, - 0xa9e2d0a0u, 0xa820ba97u, 0xaa6604ceu, 0xaba46ef9u, 0xaeeb787cu, 0xaf29124bu, 0xad6fac12u, 0xacadc625u, - 0xa7f18118u, 0xa633eb2fu, 0xa4755576u, 0xa5b73f41u, 0xa0f829c4u, 0xa13a43f3u, 0xa37cfdaau, 0xa2be979du, - 0xb5c473d0u, 0xb40619e7u, 0xb640a7beu, 0xb782cd89u, 0xb2cddb0cu, 0xb30fb13bu, 0xb1490f62u, 0xb08b6555u, - 0xbbd72268u, 0xba15485fu, 0xb853f606u, 0xb9919c31u, 0xbcde8ab4u, 0xbd1ce083u, 0xbf5a5edau, 0xbe9834edu -}; - -static const unsigned lodepng_crc32_table3[256] = { - 0x00000000u, 0xb8bc6765u, 0xaa09c88bu, 0x12b5afeeu, 0x8f629757u, 0x37def032u, 0x256b5fdcu, 0x9dd738b9u, - 0xc5b428efu, 0x7d084f8au, 0x6fbde064u, 0xd7018701u, 0x4ad6bfb8u, 0xf26ad8ddu, 0xe0df7733u, 0x58631056u, - 0x5019579fu, 0xe8a530fau, 0xfa109f14u, 0x42acf871u, 0xdf7bc0c8u, 0x67c7a7adu, 0x75720843u, 0xcdce6f26u, - 0x95ad7f70u, 0x2d111815u, 0x3fa4b7fbu, 0x8718d09eu, 0x1acfe827u, 0xa2738f42u, 0xb0c620acu, 0x087a47c9u, - 0xa032af3eu, 0x188ec85bu, 0x0a3b67b5u, 0xb28700d0u, 0x2f503869u, 0x97ec5f0cu, 0x8559f0e2u, 0x3de59787u, - 0x658687d1u, 0xdd3ae0b4u, 0xcf8f4f5au, 0x7733283fu, 0xeae41086u, 0x525877e3u, 0x40edd80du, 0xf851bf68u, - 0xf02bf8a1u, 0x48979fc4u, 0x5a22302au, 0xe29e574fu, 0x7f496ff6u, 0xc7f50893u, 0xd540a77du, 0x6dfcc018u, - 0x359fd04eu, 0x8d23b72bu, 0x9f9618c5u, 0x272a7fa0u, 0xbafd4719u, 0x0241207cu, 0x10f48f92u, 0xa848e8f7u, - 0x9b14583du, 0x23a83f58u, 0x311d90b6u, 0x89a1f7d3u, 0x1476cf6au, 0xaccaa80fu, 0xbe7f07e1u, 0x06c36084u, - 0x5ea070d2u, 0xe61c17b7u, 0xf4a9b859u, 0x4c15df3cu, 0xd1c2e785u, 0x697e80e0u, 0x7bcb2f0eu, 0xc377486bu, - 0xcb0d0fa2u, 0x73b168c7u, 0x6104c729u, 0xd9b8a04cu, 0x446f98f5u, 0xfcd3ff90u, 0xee66507eu, 0x56da371bu, - 0x0eb9274du, 0xb6054028u, 0xa4b0efc6u, 0x1c0c88a3u, 0x81dbb01au, 0x3967d77fu, 0x2bd27891u, 0x936e1ff4u, - 0x3b26f703u, 0x839a9066u, 0x912f3f88u, 0x299358edu, 0xb4446054u, 0x0cf80731u, 0x1e4da8dfu, 0xa6f1cfbau, - 0xfe92dfecu, 0x462eb889u, 0x549b1767u, 0xec277002u, 0x71f048bbu, 0xc94c2fdeu, 0xdbf98030u, 0x6345e755u, - 0x6b3fa09cu, 0xd383c7f9u, 0xc1366817u, 0x798a0f72u, 0xe45d37cbu, 0x5ce150aeu, 0x4e54ff40u, 0xf6e89825u, - 0xae8b8873u, 0x1637ef16u, 0x048240f8u, 0xbc3e279du, 0x21e91f24u, 0x99557841u, 0x8be0d7afu, 0x335cb0cau, - 0xed59b63bu, 0x55e5d15eu, 0x47507eb0u, 0xffec19d5u, 0x623b216cu, 0xda874609u, 0xc832e9e7u, 0x708e8e82u, - 0x28ed9ed4u, 0x9051f9b1u, 0x82e4565fu, 0x3a58313au, 0xa78f0983u, 0x1f336ee6u, 0x0d86c108u, 0xb53aa66du, - 0xbd40e1a4u, 0x05fc86c1u, 0x1749292fu, 0xaff54e4au, 0x322276f3u, 0x8a9e1196u, 0x982bbe78u, 0x2097d91du, - 0x78f4c94bu, 0xc048ae2eu, 0xd2fd01c0u, 0x6a4166a5u, 0xf7965e1cu, 0x4f2a3979u, 0x5d9f9697u, 0xe523f1f2u, - 0x4d6b1905u, 0xf5d77e60u, 0xe762d18eu, 0x5fdeb6ebu, 0xc2098e52u, 0x7ab5e937u, 0x680046d9u, 0xd0bc21bcu, - 0x88df31eau, 0x3063568fu, 0x22d6f961u, 0x9a6a9e04u, 0x07bda6bdu, 0xbf01c1d8u, 0xadb46e36u, 0x15080953u, - 0x1d724e9au, 0xa5ce29ffu, 0xb77b8611u, 0x0fc7e174u, 0x9210d9cdu, 0x2aacbea8u, 0x38191146u, 0x80a57623u, - 0xd8c66675u, 0x607a0110u, 0x72cfaefeu, 0xca73c99bu, 0x57a4f122u, 0xef189647u, 0xfdad39a9u, 0x45115eccu, - 0x764dee06u, 0xcef18963u, 0xdc44268du, 0x64f841e8u, 0xf92f7951u, 0x41931e34u, 0x5326b1dau, 0xeb9ad6bfu, - 0xb3f9c6e9u, 0x0b45a18cu, 0x19f00e62u, 0xa14c6907u, 0x3c9b51beu, 0x842736dbu, 0x96929935u, 0x2e2efe50u, - 0x2654b999u, 0x9ee8defcu, 0x8c5d7112u, 0x34e11677u, 0xa9362eceu, 0x118a49abu, 0x033fe645u, 0xbb838120u, - 0xe3e09176u, 0x5b5cf613u, 0x49e959fdu, 0xf1553e98u, 0x6c820621u, 0xd43e6144u, 0xc68bceaau, 0x7e37a9cfu, - 0xd67f4138u, 0x6ec3265du, 0x7c7689b3u, 0xc4caeed6u, 0x591dd66fu, 0xe1a1b10au, 0xf3141ee4u, 0x4ba87981u, - 0x13cb69d7u, 0xab770eb2u, 0xb9c2a15cu, 0x017ec639u, 0x9ca9fe80u, 0x241599e5u, 0x36a0360bu, 0x8e1c516eu, - 0x866616a7u, 0x3eda71c2u, 0x2c6fde2cu, 0x94d3b949u, 0x090481f0u, 0xb1b8e695u, 0xa30d497bu, 0x1bb12e1eu, - 0x43d23e48u, 0xfb6e592du, 0xe9dbf6c3u, 0x516791a6u, 0xccb0a91fu, 0x740cce7au, 0x66b96194u, 0xde0506f1u -}; - -static const unsigned lodepng_crc32_table4[256] = { - 0x00000000u, 0x3d6029b0u, 0x7ac05360u, 0x47a07ad0u, 0xf580a6c0u, 0xc8e08f70u, 0x8f40f5a0u, 0xb220dc10u, - 0x30704bc1u, 0x0d106271u, 0x4ab018a1u, 0x77d03111u, 0xc5f0ed01u, 0xf890c4b1u, 0xbf30be61u, 0x825097d1u, - 0x60e09782u, 0x5d80be32u, 0x1a20c4e2u, 0x2740ed52u, 0x95603142u, 0xa80018f2u, 0xefa06222u, 0xd2c04b92u, - 0x5090dc43u, 0x6df0f5f3u, 0x2a508f23u, 0x1730a693u, 0xa5107a83u, 0x98705333u, 0xdfd029e3u, 0xe2b00053u, - 0xc1c12f04u, 0xfca106b4u, 0xbb017c64u, 0x866155d4u, 0x344189c4u, 0x0921a074u, 0x4e81daa4u, 0x73e1f314u, - 0xf1b164c5u, 0xccd14d75u, 0x8b7137a5u, 0xb6111e15u, 0x0431c205u, 0x3951ebb5u, 0x7ef19165u, 0x4391b8d5u, - 0xa121b886u, 0x9c419136u, 0xdbe1ebe6u, 0xe681c256u, 0x54a11e46u, 0x69c137f6u, 0x2e614d26u, 0x13016496u, - 0x9151f347u, 0xac31daf7u, 0xeb91a027u, 0xd6f18997u, 0x64d15587u, 0x59b17c37u, 0x1e1106e7u, 0x23712f57u, - 0x58f35849u, 0x659371f9u, 0x22330b29u, 0x1f532299u, 0xad73fe89u, 0x9013d739u, 0xd7b3ade9u, 0xead38459u, - 0x68831388u, 0x55e33a38u, 0x124340e8u, 0x2f236958u, 0x9d03b548u, 0xa0639cf8u, 0xe7c3e628u, 0xdaa3cf98u, - 0x3813cfcbu, 0x0573e67bu, 0x42d39cabu, 0x7fb3b51bu, 0xcd93690bu, 0xf0f340bbu, 0xb7533a6bu, 0x8a3313dbu, - 0x0863840au, 0x3503adbau, 0x72a3d76au, 0x4fc3fedau, 0xfde322cau, 0xc0830b7au, 0x872371aau, 0xba43581au, - 0x9932774du, 0xa4525efdu, 0xe3f2242du, 0xde920d9du, 0x6cb2d18du, 0x51d2f83du, 0x167282edu, 0x2b12ab5du, - 0xa9423c8cu, 0x9422153cu, 0xd3826fecu, 0xeee2465cu, 0x5cc29a4cu, 0x61a2b3fcu, 0x2602c92cu, 0x1b62e09cu, - 0xf9d2e0cfu, 0xc4b2c97fu, 0x8312b3afu, 0xbe729a1fu, 0x0c52460fu, 0x31326fbfu, 0x7692156fu, 0x4bf23cdfu, - 0xc9a2ab0eu, 0xf4c282beu, 0xb362f86eu, 0x8e02d1deu, 0x3c220dceu, 0x0142247eu, 0x46e25eaeu, 0x7b82771eu, - 0xb1e6b092u, 0x8c869922u, 0xcb26e3f2u, 0xf646ca42u, 0x44661652u, 0x79063fe2u, 0x3ea64532u, 0x03c66c82u, - 0x8196fb53u, 0xbcf6d2e3u, 0xfb56a833u, 0xc6368183u, 0x74165d93u, 0x49767423u, 0x0ed60ef3u, 0x33b62743u, - 0xd1062710u, 0xec660ea0u, 0xabc67470u, 0x96a65dc0u, 0x248681d0u, 0x19e6a860u, 0x5e46d2b0u, 0x6326fb00u, - 0xe1766cd1u, 0xdc164561u, 0x9bb63fb1u, 0xa6d61601u, 0x14f6ca11u, 0x2996e3a1u, 0x6e369971u, 0x5356b0c1u, - 0x70279f96u, 0x4d47b626u, 0x0ae7ccf6u, 0x3787e546u, 0x85a73956u, 0xb8c710e6u, 0xff676a36u, 0xc2074386u, - 0x4057d457u, 0x7d37fde7u, 0x3a978737u, 0x07f7ae87u, 0xb5d77297u, 0x88b75b27u, 0xcf1721f7u, 0xf2770847u, - 0x10c70814u, 0x2da721a4u, 0x6a075b74u, 0x576772c4u, 0xe547aed4u, 0xd8278764u, 0x9f87fdb4u, 0xa2e7d404u, - 0x20b743d5u, 0x1dd76a65u, 0x5a7710b5u, 0x67173905u, 0xd537e515u, 0xe857cca5u, 0xaff7b675u, 0x92979fc5u, - 0xe915e8dbu, 0xd475c16bu, 0x93d5bbbbu, 0xaeb5920bu, 0x1c954e1bu, 0x21f567abu, 0x66551d7bu, 0x5b3534cbu, - 0xd965a31au, 0xe4058aaau, 0xa3a5f07au, 0x9ec5d9cau, 0x2ce505dau, 0x11852c6au, 0x562556bau, 0x6b457f0au, - 0x89f57f59u, 0xb49556e9u, 0xf3352c39u, 0xce550589u, 0x7c75d999u, 0x4115f029u, 0x06b58af9u, 0x3bd5a349u, - 0xb9853498u, 0x84e51d28u, 0xc34567f8u, 0xfe254e48u, 0x4c059258u, 0x7165bbe8u, 0x36c5c138u, 0x0ba5e888u, - 0x28d4c7dfu, 0x15b4ee6fu, 0x521494bfu, 0x6f74bd0fu, 0xdd54611fu, 0xe03448afu, 0xa794327fu, 0x9af41bcfu, - 0x18a48c1eu, 0x25c4a5aeu, 0x6264df7eu, 0x5f04f6ceu, 0xed242adeu, 0xd044036eu, 0x97e479beu, 0xaa84500eu, - 0x4834505du, 0x755479edu, 0x32f4033du, 0x0f942a8du, 0xbdb4f69du, 0x80d4df2du, 0xc774a5fdu, 0xfa148c4du, - 0x78441b9cu, 0x4524322cu, 0x028448fcu, 0x3fe4614cu, 0x8dc4bd5cu, 0xb0a494ecu, 0xf704ee3cu, 0xca64c78cu -}; - -static const unsigned lodepng_crc32_table5[256] = { - 0x00000000u, 0xcb5cd3a5u, 0x4dc8a10bu, 0x869472aeu, 0x9b914216u, 0x50cd91b3u, 0xd659e31du, 0x1d0530b8u, - 0xec53826du, 0x270f51c8u, 0xa19b2366u, 0x6ac7f0c3u, 0x77c2c07bu, 0xbc9e13deu, 0x3a0a6170u, 0xf156b2d5u, - 0x03d6029bu, 0xc88ad13eu, 0x4e1ea390u, 0x85427035u, 0x9847408du, 0x531b9328u, 0xd58fe186u, 0x1ed33223u, - 0xef8580f6u, 0x24d95353u, 0xa24d21fdu, 0x6911f258u, 0x7414c2e0u, 0xbf481145u, 0x39dc63ebu, 0xf280b04eu, - 0x07ac0536u, 0xccf0d693u, 0x4a64a43du, 0x81387798u, 0x9c3d4720u, 0x57619485u, 0xd1f5e62bu, 0x1aa9358eu, - 0xebff875bu, 0x20a354feu, 0xa6372650u, 0x6d6bf5f5u, 0x706ec54du, 0xbb3216e8u, 0x3da66446u, 0xf6fab7e3u, - 0x047a07adu, 0xcf26d408u, 0x49b2a6a6u, 0x82ee7503u, 0x9feb45bbu, 0x54b7961eu, 0xd223e4b0u, 0x197f3715u, - 0xe82985c0u, 0x23755665u, 0xa5e124cbu, 0x6ebdf76eu, 0x73b8c7d6u, 0xb8e41473u, 0x3e7066ddu, 0xf52cb578u, - 0x0f580a6cu, 0xc404d9c9u, 0x4290ab67u, 0x89cc78c2u, 0x94c9487au, 0x5f959bdfu, 0xd901e971u, 0x125d3ad4u, - 0xe30b8801u, 0x28575ba4u, 0xaec3290au, 0x659ffaafu, 0x789aca17u, 0xb3c619b2u, 0x35526b1cu, 0xfe0eb8b9u, - 0x0c8e08f7u, 0xc7d2db52u, 0x4146a9fcu, 0x8a1a7a59u, 0x971f4ae1u, 0x5c439944u, 0xdad7ebeau, 0x118b384fu, - 0xe0dd8a9au, 0x2b81593fu, 0xad152b91u, 0x6649f834u, 0x7b4cc88cu, 0xb0101b29u, 0x36846987u, 0xfdd8ba22u, - 0x08f40f5au, 0xc3a8dcffu, 0x453cae51u, 0x8e607df4u, 0x93654d4cu, 0x58399ee9u, 0xdeadec47u, 0x15f13fe2u, - 0xe4a78d37u, 0x2ffb5e92u, 0xa96f2c3cu, 0x6233ff99u, 0x7f36cf21u, 0xb46a1c84u, 0x32fe6e2au, 0xf9a2bd8fu, - 0x0b220dc1u, 0xc07ede64u, 0x46eaaccau, 0x8db67f6fu, 0x90b34fd7u, 0x5bef9c72u, 0xdd7beedcu, 0x16273d79u, - 0xe7718facu, 0x2c2d5c09u, 0xaab92ea7u, 0x61e5fd02u, 0x7ce0cdbau, 0xb7bc1e1fu, 0x31286cb1u, 0xfa74bf14u, - 0x1eb014d8u, 0xd5ecc77du, 0x5378b5d3u, 0x98246676u, 0x852156ceu, 0x4e7d856bu, 0xc8e9f7c5u, 0x03b52460u, - 0xf2e396b5u, 0x39bf4510u, 0xbf2b37beu, 0x7477e41bu, 0x6972d4a3u, 0xa22e0706u, 0x24ba75a8u, 0xefe6a60du, - 0x1d661643u, 0xd63ac5e6u, 0x50aeb748u, 0x9bf264edu, 0x86f75455u, 0x4dab87f0u, 0xcb3ff55eu, 0x006326fbu, - 0xf135942eu, 0x3a69478bu, 0xbcfd3525u, 0x77a1e680u, 0x6aa4d638u, 0xa1f8059du, 0x276c7733u, 0xec30a496u, - 0x191c11eeu, 0xd240c24bu, 0x54d4b0e5u, 0x9f886340u, 0x828d53f8u, 0x49d1805du, 0xcf45f2f3u, 0x04192156u, - 0xf54f9383u, 0x3e134026u, 0xb8873288u, 0x73dbe12du, 0x6eded195u, 0xa5820230u, 0x2316709eu, 0xe84aa33bu, - 0x1aca1375u, 0xd196c0d0u, 0x5702b27eu, 0x9c5e61dbu, 0x815b5163u, 0x4a0782c6u, 0xcc93f068u, 0x07cf23cdu, - 0xf6999118u, 0x3dc542bdu, 0xbb513013u, 0x700de3b6u, 0x6d08d30eu, 0xa65400abu, 0x20c07205u, 0xeb9ca1a0u, - 0x11e81eb4u, 0xdab4cd11u, 0x5c20bfbfu, 0x977c6c1au, 0x8a795ca2u, 0x41258f07u, 0xc7b1fda9u, 0x0ced2e0cu, - 0xfdbb9cd9u, 0x36e74f7cu, 0xb0733dd2u, 0x7b2fee77u, 0x662adecfu, 0xad760d6au, 0x2be27fc4u, 0xe0beac61u, - 0x123e1c2fu, 0xd962cf8au, 0x5ff6bd24u, 0x94aa6e81u, 0x89af5e39u, 0x42f38d9cu, 0xc467ff32u, 0x0f3b2c97u, - 0xfe6d9e42u, 0x35314de7u, 0xb3a53f49u, 0x78f9ececu, 0x65fcdc54u, 0xaea00ff1u, 0x28347d5fu, 0xe368aefau, - 0x16441b82u, 0xdd18c827u, 0x5b8cba89u, 0x90d0692cu, 0x8dd55994u, 0x46898a31u, 0xc01df89fu, 0x0b412b3au, - 0xfa1799efu, 0x314b4a4au, 0xb7df38e4u, 0x7c83eb41u, 0x6186dbf9u, 0xaada085cu, 0x2c4e7af2u, 0xe712a957u, - 0x15921919u, 0xdececabcu, 0x585ab812u, 0x93066bb7u, 0x8e035b0fu, 0x455f88aau, 0xc3cbfa04u, 0x089729a1u, - 0xf9c19b74u, 0x329d48d1u, 0xb4093a7fu, 0x7f55e9dau, 0x6250d962u, 0xa90c0ac7u, 0x2f987869u, 0xe4c4abccu -}; - -static const unsigned lodepng_crc32_table6[256] = { - 0x00000000u, 0xa6770bb4u, 0x979f1129u, 0x31e81a9du, 0xf44f2413u, 0x52382fa7u, 0x63d0353au, 0xc5a73e8eu, - 0x33ef4e67u, 0x959845d3u, 0xa4705f4eu, 0x020754fau, 0xc7a06a74u, 0x61d761c0u, 0x503f7b5du, 0xf64870e9u, - 0x67de9cceu, 0xc1a9977au, 0xf0418de7u, 0x56368653u, 0x9391b8ddu, 0x35e6b369u, 0x040ea9f4u, 0xa279a240u, - 0x5431d2a9u, 0xf246d91du, 0xc3aec380u, 0x65d9c834u, 0xa07ef6bau, 0x0609fd0eu, 0x37e1e793u, 0x9196ec27u, - 0xcfbd399cu, 0x69ca3228u, 0x582228b5u, 0xfe552301u, 0x3bf21d8fu, 0x9d85163bu, 0xac6d0ca6u, 0x0a1a0712u, - 0xfc5277fbu, 0x5a257c4fu, 0x6bcd66d2u, 0xcdba6d66u, 0x081d53e8u, 0xae6a585cu, 0x9f8242c1u, 0x39f54975u, - 0xa863a552u, 0x0e14aee6u, 0x3ffcb47bu, 0x998bbfcfu, 0x5c2c8141u, 0xfa5b8af5u, 0xcbb39068u, 0x6dc49bdcu, - 0x9b8ceb35u, 0x3dfbe081u, 0x0c13fa1cu, 0xaa64f1a8u, 0x6fc3cf26u, 0xc9b4c492u, 0xf85cde0fu, 0x5e2bd5bbu, - 0x440b7579u, 0xe27c7ecdu, 0xd3946450u, 0x75e36fe4u, 0xb044516au, 0x16335adeu, 0x27db4043u, 0x81ac4bf7u, - 0x77e43b1eu, 0xd19330aau, 0xe07b2a37u, 0x460c2183u, 0x83ab1f0du, 0x25dc14b9u, 0x14340e24u, 0xb2430590u, - 0x23d5e9b7u, 0x85a2e203u, 0xb44af89eu, 0x123df32au, 0xd79acda4u, 0x71edc610u, 0x4005dc8du, 0xe672d739u, - 0x103aa7d0u, 0xb64dac64u, 0x87a5b6f9u, 0x21d2bd4du, 0xe47583c3u, 0x42028877u, 0x73ea92eau, 0xd59d995eu, - 0x8bb64ce5u, 0x2dc14751u, 0x1c295dccu, 0xba5e5678u, 0x7ff968f6u, 0xd98e6342u, 0xe86679dfu, 0x4e11726bu, - 0xb8590282u, 0x1e2e0936u, 0x2fc613abu, 0x89b1181fu, 0x4c162691u, 0xea612d25u, 0xdb8937b8u, 0x7dfe3c0cu, - 0xec68d02bu, 0x4a1fdb9fu, 0x7bf7c102u, 0xdd80cab6u, 0x1827f438u, 0xbe50ff8cu, 0x8fb8e511u, 0x29cfeea5u, - 0xdf879e4cu, 0x79f095f8u, 0x48188f65u, 0xee6f84d1u, 0x2bc8ba5fu, 0x8dbfb1ebu, 0xbc57ab76u, 0x1a20a0c2u, - 0x8816eaf2u, 0x2e61e146u, 0x1f89fbdbu, 0xb9fef06fu, 0x7c59cee1u, 0xda2ec555u, 0xebc6dfc8u, 0x4db1d47cu, - 0xbbf9a495u, 0x1d8eaf21u, 0x2c66b5bcu, 0x8a11be08u, 0x4fb68086u, 0xe9c18b32u, 0xd82991afu, 0x7e5e9a1bu, - 0xefc8763cu, 0x49bf7d88u, 0x78576715u, 0xde206ca1u, 0x1b87522fu, 0xbdf0599bu, 0x8c184306u, 0x2a6f48b2u, - 0xdc27385bu, 0x7a5033efu, 0x4bb82972u, 0xedcf22c6u, 0x28681c48u, 0x8e1f17fcu, 0xbff70d61u, 0x198006d5u, - 0x47abd36eu, 0xe1dcd8dau, 0xd034c247u, 0x7643c9f3u, 0xb3e4f77du, 0x1593fcc9u, 0x247be654u, 0x820cede0u, - 0x74449d09u, 0xd23396bdu, 0xe3db8c20u, 0x45ac8794u, 0x800bb91au, 0x267cb2aeu, 0x1794a833u, 0xb1e3a387u, - 0x20754fa0u, 0x86024414u, 0xb7ea5e89u, 0x119d553du, 0xd43a6bb3u, 0x724d6007u, 0x43a57a9au, 0xe5d2712eu, - 0x139a01c7u, 0xb5ed0a73u, 0x840510eeu, 0x22721b5au, 0xe7d525d4u, 0x41a22e60u, 0x704a34fdu, 0xd63d3f49u, - 0xcc1d9f8bu, 0x6a6a943fu, 0x5b828ea2u, 0xfdf58516u, 0x3852bb98u, 0x9e25b02cu, 0xafcdaab1u, 0x09baa105u, - 0xfff2d1ecu, 0x5985da58u, 0x686dc0c5u, 0xce1acb71u, 0x0bbdf5ffu, 0xadcafe4bu, 0x9c22e4d6u, 0x3a55ef62u, - 0xabc30345u, 0x0db408f1u, 0x3c5c126cu, 0x9a2b19d8u, 0x5f8c2756u, 0xf9fb2ce2u, 0xc813367fu, 0x6e643dcbu, - 0x982c4d22u, 0x3e5b4696u, 0x0fb35c0bu, 0xa9c457bfu, 0x6c636931u, 0xca146285u, 0xfbfc7818u, 0x5d8b73acu, - 0x03a0a617u, 0xa5d7ada3u, 0x943fb73eu, 0x3248bc8au, 0xf7ef8204u, 0x519889b0u, 0x6070932du, 0xc6079899u, - 0x304fe870u, 0x9638e3c4u, 0xa7d0f959u, 0x01a7f2edu, 0xc400cc63u, 0x6277c7d7u, 0x539fdd4au, 0xf5e8d6feu, - 0x647e3ad9u, 0xc209316du, 0xf3e12bf0u, 0x55962044u, 0x90311ecau, 0x3646157eu, 0x07ae0fe3u, 0xa1d90457u, - 0x579174beu, 0xf1e67f0au, 0xc00e6597u, 0x66796e23u, 0xa3de50adu, 0x05a95b19u, 0x34414184u, 0x92364a30u -}; - -static const unsigned lodepng_crc32_table7[256] = { - 0x00000000u, 0xccaa009eu, 0x4225077du, 0x8e8f07e3u, 0x844a0efau, 0x48e00e64u, 0xc66f0987u, 0x0ac50919u, - 0xd3e51bb5u, 0x1f4f1b2bu, 0x91c01cc8u, 0x5d6a1c56u, 0x57af154fu, 0x9b0515d1u, 0x158a1232u, 0xd92012acu, - 0x7cbb312bu, 0xb01131b5u, 0x3e9e3656u, 0xf23436c8u, 0xf8f13fd1u, 0x345b3f4fu, 0xbad438acu, 0x767e3832u, - 0xaf5e2a9eu, 0x63f42a00u, 0xed7b2de3u, 0x21d12d7du, 0x2b142464u, 0xe7be24fau, 0x69312319u, 0xa59b2387u, - 0xf9766256u, 0x35dc62c8u, 0xbb53652bu, 0x77f965b5u, 0x7d3c6cacu, 0xb1966c32u, 0x3f196bd1u, 0xf3b36b4fu, - 0x2a9379e3u, 0xe639797du, 0x68b67e9eu, 0xa41c7e00u, 0xaed97719u, 0x62737787u, 0xecfc7064u, 0x205670fau, - 0x85cd537du, 0x496753e3u, 0xc7e85400u, 0x0b42549eu, 0x01875d87u, 0xcd2d5d19u, 0x43a25afau, 0x8f085a64u, - 0x562848c8u, 0x9a824856u, 0x140d4fb5u, 0xd8a74f2bu, 0xd2624632u, 0x1ec846acu, 0x9047414fu, 0x5ced41d1u, - 0x299dc2edu, 0xe537c273u, 0x6bb8c590u, 0xa712c50eu, 0xadd7cc17u, 0x617dcc89u, 0xeff2cb6au, 0x2358cbf4u, - 0xfa78d958u, 0x36d2d9c6u, 0xb85dde25u, 0x74f7debbu, 0x7e32d7a2u, 0xb298d73cu, 0x3c17d0dfu, 0xf0bdd041u, - 0x5526f3c6u, 0x998cf358u, 0x1703f4bbu, 0xdba9f425u, 0xd16cfd3cu, 0x1dc6fda2u, 0x9349fa41u, 0x5fe3fadfu, - 0x86c3e873u, 0x4a69e8edu, 0xc4e6ef0eu, 0x084cef90u, 0x0289e689u, 0xce23e617u, 0x40ace1f4u, 0x8c06e16au, - 0xd0eba0bbu, 0x1c41a025u, 0x92cea7c6u, 0x5e64a758u, 0x54a1ae41u, 0x980baedfu, 0x1684a93cu, 0xda2ea9a2u, - 0x030ebb0eu, 0xcfa4bb90u, 0x412bbc73u, 0x8d81bcedu, 0x8744b5f4u, 0x4beeb56au, 0xc561b289u, 0x09cbb217u, - 0xac509190u, 0x60fa910eu, 0xee7596edu, 0x22df9673u, 0x281a9f6au, 0xe4b09ff4u, 0x6a3f9817u, 0xa6959889u, - 0x7fb58a25u, 0xb31f8abbu, 0x3d908d58u, 0xf13a8dc6u, 0xfbff84dfu, 0x37558441u, 0xb9da83a2u, 0x7570833cu, - 0x533b85dau, 0x9f918544u, 0x111e82a7u, 0xddb48239u, 0xd7718b20u, 0x1bdb8bbeu, 0x95548c5du, 0x59fe8cc3u, - 0x80de9e6fu, 0x4c749ef1u, 0xc2fb9912u, 0x0e51998cu, 0x04949095u, 0xc83e900bu, 0x46b197e8u, 0x8a1b9776u, - 0x2f80b4f1u, 0xe32ab46fu, 0x6da5b38cu, 0xa10fb312u, 0xabcaba0bu, 0x6760ba95u, 0xe9efbd76u, 0x2545bde8u, - 0xfc65af44u, 0x30cfafdau, 0xbe40a839u, 0x72eaa8a7u, 0x782fa1beu, 0xb485a120u, 0x3a0aa6c3u, 0xf6a0a65du, - 0xaa4de78cu, 0x66e7e712u, 0xe868e0f1u, 0x24c2e06fu, 0x2e07e976u, 0xe2ade9e8u, 0x6c22ee0bu, 0xa088ee95u, - 0x79a8fc39u, 0xb502fca7u, 0x3b8dfb44u, 0xf727fbdau, 0xfde2f2c3u, 0x3148f25du, 0xbfc7f5beu, 0x736df520u, - 0xd6f6d6a7u, 0x1a5cd639u, 0x94d3d1dau, 0x5879d144u, 0x52bcd85du, 0x9e16d8c3u, 0x1099df20u, 0xdc33dfbeu, - 0x0513cd12u, 0xc9b9cd8cu, 0x4736ca6fu, 0x8b9ccaf1u, 0x8159c3e8u, 0x4df3c376u, 0xc37cc495u, 0x0fd6c40bu, - 0x7aa64737u, 0xb60c47a9u, 0x3883404au, 0xf42940d4u, 0xfeec49cdu, 0x32464953u, 0xbcc94eb0u, 0x70634e2eu, - 0xa9435c82u, 0x65e95c1cu, 0xeb665bffu, 0x27cc5b61u, 0x2d095278u, 0xe1a352e6u, 0x6f2c5505u, 0xa386559bu, - 0x061d761cu, 0xcab77682u, 0x44387161u, 0x889271ffu, 0x825778e6u, 0x4efd7878u, 0xc0727f9bu, 0x0cd87f05u, - 0xd5f86da9u, 0x19526d37u, 0x97dd6ad4u, 0x5b776a4au, 0x51b26353u, 0x9d1863cdu, 0x1397642eu, 0xdf3d64b0u, - 0x83d02561u, 0x4f7a25ffu, 0xc1f5221cu, 0x0d5f2282u, 0x079a2b9bu, 0xcb302b05u, 0x45bf2ce6u, 0x89152c78u, - 0x50353ed4u, 0x9c9f3e4au, 0x121039a9u, 0xdeba3937u, 0xd47f302eu, 0x18d530b0u, 0x965a3753u, 0x5af037cdu, - 0xff6b144au, 0x33c114d4u, 0xbd4e1337u, 0x71e413a9u, 0x7b211ab0u, 0xb78b1a2eu, 0x39041dcdu, 0xf5ae1d53u, - 0x2c8e0fffu, 0xe0240f61u, 0x6eab0882u, 0xa201081cu, 0xa8c40105u, 0x646e019bu, 0xeae10678u, 0x264b06e6u -}; - -/* Computes the cyclic redundancy check as used by PNG chunks*/ -unsigned lodepng_crc32(const unsigned char* data, size_t length) { - /*Using the Slicing by Eight algorithm*/ - unsigned r = 0xffffffffu; - while(length >= 8) { - r = lodepng_crc32_table7[(data[0] ^ (r & 0xffu))] ^ - lodepng_crc32_table6[(data[1] ^ ((r >> 8) & 0xffu))] ^ - lodepng_crc32_table5[(data[2] ^ ((r >> 16) & 0xffu))] ^ - lodepng_crc32_table4[(data[3] ^ ((r >> 24) & 0xffu))] ^ - lodepng_crc32_table3[data[4]] ^ - lodepng_crc32_table2[data[5]] ^ - lodepng_crc32_table1[data[6]] ^ - lodepng_crc32_table0[data[7]]; - data += 8; - length -= 8; - } - while(length--) { - r = lodepng_crc32_table0[(r ^ *data++) & 0xffu] ^ (r >> 8); - } - return r ^ 0xffffffffu; -} -#else /* LODEPNG_COMPILE_CRC */ -/*in this case, the function is only declared here, and must be defined externally -so that it will be linked in. - -Example implementation that uses a much smaller lookup table for memory constrained cases: - -unsigned lodepng_crc32(const unsigned char* data, size_t length) { - unsigned r = 0xffffffffu; - static const unsigned table[16] = { - 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, - 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c - }; - while(length--) { - r = table[(r ^ *data) & 0xf] ^ (r >> 4); - r = table[(r ^ (*data >> 4)) & 0xf] ^ (r >> 4); - data++; - } - return r ^ 0xffffffffu; -} -*/ -unsigned lodepng_crc32(const unsigned char* data, size_t length); -#endif /* LODEPNG_COMPILE_CRC */ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Reading and writing PNG color channel bits / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -/* The color channel bits of less-than-8-bit pixels are read with the MSB of bytes first, -so LodePNGBitWriter and LodePNGBitReader can't be used for those. */ - -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; -} - -/* TODO: make this faster */ -static unsigned readBitsFromReversedStream(size_t* bitpointer, const unsigned char* bitstream, size_t nbits) { - unsigned result = 0; - size_t i; - for(i = 0 ; i < nbits; ++i) { - result <<= 1u; - result |= (unsigned)readBitFromReversedStream(bitpointer, bitstream); - } - return result; -} - -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) >> 3u] &= (unsigned char)(~(1u << (7u - ((*bitpointer) & 7u)))); - else bitstream[(*bitpointer) >> 3u] |= (1u << (7u - ((*bitpointer) & 7u))); - ++(*bitpointer); -} - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / PNG chunks / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -unsigned lodepng_chunk_length(const unsigned char* chunk) { - return lodepng_read32bitInt(chunk); -} - -void lodepng_chunk_type(char type[5], const unsigned char* chunk) { - unsigned i; - for(i = 0; i != 4; ++i) type[i] = (char)chunk[4 + i]; - type[4] = 0; /*null termination char*/ -} - -unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type) { - if(lodepng_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_ancillary(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 = lodepng_crc32(&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 = lodepng_crc32(&chunk[4], length + 4); - lodepng_set32bitInt(chunk + 8 + length, CRC); -} - -unsigned char* lodepng_chunk_next(unsigned char* chunk, unsigned char* end) { - size_t available_size = (size_t)(end - chunk); - if(chunk >= end || available_size < 12) return end; /*too small to contain a chunk*/ - if(chunk[0] == 0x89 && chunk[1] == 0x50 && chunk[2] == 0x4e && chunk[3] == 0x47 - && chunk[4] == 0x0d && chunk[5] == 0x0a && chunk[6] == 0x1a && chunk[7] == 0x0a) { - /* Is PNG magic header at start of PNG file. Jump to first actual chunk. */ - return chunk + 8; - } else { - size_t total_chunk_length; - if(lodepng_addofl(lodepng_chunk_length(chunk), 12, &total_chunk_length)) return end; - if(total_chunk_length > available_size) return end; /*outside of range*/ - return chunk + total_chunk_length; - } -} - -const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk, const unsigned char* end) { - size_t available_size = (size_t)(end - chunk); - if(chunk >= end || available_size < 12) return end; /*too small to contain a chunk*/ - if(chunk[0] == 0x89 && chunk[1] == 0x50 && chunk[2] == 0x4e && chunk[3] == 0x47 - && chunk[4] == 0x0d && chunk[5] == 0x0a && chunk[6] == 0x1a && chunk[7] == 0x0a) { - /* Is PNG magic header at start of PNG file. Jump to first actual chunk. */ - return chunk + 8; - } else { - size_t total_chunk_length; - if(lodepng_addofl(lodepng_chunk_length(chunk), 12, &total_chunk_length)) return end; - if(total_chunk_length > available_size) return end; /*outside of range*/ - return chunk + total_chunk_length; - } -} - -unsigned char* lodepng_chunk_find(unsigned char* chunk, unsigned char* end, const char type[5]) { - for(;;) { - if(chunk >= end || end - chunk < 12) return 0; /* past file end: chunk + 12 > end */ - if(lodepng_chunk_type_equals(chunk, type)) return chunk; - chunk = lodepng_chunk_next(chunk, end); - } -} - -const unsigned char* lodepng_chunk_find_const(const unsigned char* chunk, const unsigned char* end, const char type[5]) { - for(;;) { - if(chunk >= end || end - chunk < 12) return 0; /* past file end: chunk + 12 > end */ - if(lodepng_chunk_type_equals(chunk, type)) return chunk; - chunk = lodepng_chunk_next_const(chunk, end); - } -} - -unsigned lodepng_chunk_append(unsigned char** out, size_t* outsize, const unsigned char* chunk) { - unsigned i; - size_t total_chunk_length, new_length; - unsigned char *chunk_start, *new_buffer; - - if(lodepng_addofl(lodepng_chunk_length(chunk), 12, &total_chunk_length)) return 77; - if(lodepng_addofl(*outsize, total_chunk_length, &new_length)) return 77; - - new_buffer = (unsigned char*)lodepng_realloc(*out, new_length); - if(!new_buffer) return 83; /*alloc fail*/ - (*out) = new_buffer; - (*outsize) = 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; -} - -/*Sets length and name and allocates the space for data and crc but does not -set data or crc yet. Returns the start of the chunk in chunk. The start of -the data is at chunk + 8. To finalize chunk, add the data, then use -lodepng_chunk_generate_crc */ -static unsigned lodepng_chunk_init(unsigned char** chunk, - ucvector* out, - unsigned length, const char* type) { - size_t new_length = out->size; - if(lodepng_addofl(new_length, length, &new_length)) return 77; - if(lodepng_addofl(new_length, 12, &new_length)) return 77; - if(!ucvector_resize(out, new_length)) return 83; /*alloc fail*/ - *chunk = out->data + new_length - length - 12u; - - /*1: length*/ - lodepng_set32bitInt(*chunk, length); - - /*2: chunk name (4 letters)*/ - lodepng_memcpy(*chunk + 4, type, 4); - - return 0; -} - -/* like lodepng_chunk_create but with custom allocsize */ -static unsigned lodepng_chunk_createv(ucvector* out, - unsigned length, const char* type, const unsigned char* data) { - unsigned char* chunk; - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, length, type)); - - /*3: the data*/ - lodepng_memcpy(chunk + 8, data, length); - - /*4: CRC (of the chunkname characters and the data)*/ - lodepng_chunk_generate_crc(chunk); - - return 0; -} - -unsigned lodepng_chunk_create(unsigned char** out, size_t* outsize, - unsigned length, const char* type, const unsigned char* data) { - ucvector v = ucvector_init(*out, *outsize); - unsigned error = lodepng_chunk_createv(&v, length, type, data); - *out = v.data; - *outsize = v.size; - return error; -} - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Color types, channels, bits / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -/*checks if the colortype is valid and the bitdepth bd is allowed for this colortype. -Return value is a LodePNG error code.*/ -static unsigned checkColorValidity(LodePNGColorType colortype, unsigned bd) { - switch(colortype) { - case LCT_GREY: if(!(bd == 1 || bd == 2 || bd == 4 || bd == 8 || bd == 16)) return 37; break; - case LCT_RGB: if(!( bd == 8 || bd == 16)) return 37; break; - case LCT_PALETTE: if(!(bd == 1 || bd == 2 || bd == 4 || bd == 8 )) return 37; break; - case LCT_GREY_ALPHA: if(!( bd == 8 || bd == 16)) return 37; break; - case LCT_RGBA: if(!( bd == 8 || bd == 16)) return 37; break; - case LCT_MAX_OCTET_VALUE: return 31; /* invalid color type */ - default: return 31; /* invalid color type */ - } - return 0; /*allowed color type / bits combination*/ -} - -static unsigned getNumColorChannels(LodePNGColorType colortype) { - switch(colortype) { - case LCT_GREY: return 1; - case LCT_RGB: return 3; - case LCT_PALETTE: return 1; - case LCT_GREY_ALPHA: return 2; - case LCT_RGBA: return 4; - case LCT_MAX_OCTET_VALUE: return 0; /* invalid color type */ - default: return 0; /*invalid color type*/ - } -} - -static unsigned lodepng_get_bpp_lct(LodePNGColorType colortype, unsigned bitdepth) { - /*bits per pixel is amount of channels * bits per channel*/ - return getNumColorChannels(colortype) * bitdepth; -} - -/* ////////////////////////////////////////////////////////////////////////// */ - -void lodepng_color_mode_init(LodePNGColorMode* info) { - info->key_defined = 0; - info->key_r = info->key_g = info->key_b = 0; - info->colortype = LCT_RGBA; - info->bitdepth = 8; - info->palette = 0; - info->palettesize = 0; -} - -/*allocates palette memory if needed, and initializes all colors to black*/ -static void lodepng_color_mode_alloc_palette(LodePNGColorMode* info) { - size_t i; - /*if the palette is already allocated, it will have size 1024 so no reallocation needed in that case*/ - /*the palette must have room for up to 256 colors with 4 bytes each.*/ - if(!info->palette) info->palette = (unsigned char*)lodepng_malloc(1024); - if(!info->palette) return; /*alloc fail*/ - for(i = 0; i != 256; ++i) { - /*Initialize all unused colors with black, the value used for invalid palette indices. - This is an error according to the PNG spec, but common PNG decoders make it black instead. - That makes color conversion slightly faster due to no error handling needed.*/ - info->palette[i * 4 + 0] = 0; - info->palette[i * 4 + 1] = 0; - info->palette[i * 4 + 2] = 0; - info->palette[i * 4 + 3] = 255; - } -} - -void lodepng_color_mode_cleanup(LodePNGColorMode* info) { - lodepng_palette_clear(info); -} - -unsigned lodepng_color_mode_copy(LodePNGColorMode* dest, const LodePNGColorMode* source) { - lodepng_color_mode_cleanup(dest); - lodepng_memcpy(dest, source, sizeof(LodePNGColorMode)); - if(source->palette) { - dest->palette = (unsigned char*)lodepng_malloc(1024); - if(!dest->palette && source->palettesize) return 83; /*alloc fail*/ - lodepng_memcpy(dest->palette, source->palette, source->palettesize * 4); - } - return 0; -} - -LodePNGColorMode lodepng_color_mode_make(LodePNGColorType colortype, unsigned bitdepth) { - LodePNGColorMode result; - lodepng_color_mode_init(&result); - result.colortype = colortype; - result.bitdepth = bitdepth; - return result; -} - -static int lodepng_color_mode_equal(const LodePNGColorMode* a, const LodePNGColorMode* b) { - size_t i; - if(a->colortype != b->colortype) return 0; - if(a->bitdepth != b->bitdepth) return 0; - if(a->key_defined != b->key_defined) return 0; - if(a->key_defined) { - if(a->key_r != b->key_r) return 0; - if(a->key_g != b->key_g) return 0; - if(a->key_b != b->key_b) return 0; - } - if(a->palettesize != b->palettesize) return 0; - for(i = 0; i != a->palettesize * 4; ++i) { - if(a->palette[i] != b->palette[i]) return 0; - } - return 1; -} - -void lodepng_palette_clear(LodePNGColorMode* info) { - if(info->palette) lodepng_free(info->palette); - info->palette = 0; - info->palettesize = 0; -} - -unsigned lodepng_palette_add(LodePNGColorMode* info, - unsigned char r, unsigned char g, unsigned char b, unsigned char a) { - if(!info->palette) /*allocate palette if empty*/ { - lodepng_color_mode_alloc_palette(info); - if(!info->palette) return 83; /*alloc fail*/ - } - if(info->palettesize >= 256) { - return 108; /*too many palette values*/ - } - 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; -} - -/*calculate bits per pixel out of colortype and bitdepth*/ -unsigned lodepng_get_bpp(const LodePNGColorMode* info) { - return lodepng_get_bpp_lct(info->colortype, info->bitdepth); -} - -unsigned lodepng_get_channels(const LodePNGColorMode* info) { - return getNumColorChannels(info->colortype); -} - -unsigned lodepng_is_greyscale_type(const LodePNGColorMode* info) { - return info->colortype == LCT_GREY || info->colortype == LCT_GREY_ALPHA; -} - -unsigned lodepng_is_alpha_type(const LodePNGColorMode* info) { - return (info->colortype & 4) != 0; /*4 or 6*/ -} - -unsigned lodepng_is_palette_type(const LodePNGColorMode* info) { - return info->colortype == LCT_PALETTE; -} - -unsigned lodepng_has_palette_alpha(const LodePNGColorMode* info) { - size_t i; - for(i = 0; i != info->palettesize; ++i) { - if(info->palette[i * 4 + 3] < 255) return 1; - } - return 0; -} - -unsigned lodepng_can_have_alpha(const LodePNGColorMode* info) { - return info->key_defined - || lodepng_is_alpha_type(info) - || lodepng_has_palette_alpha(info); -} - -static size_t lodepng_get_raw_size_lct(unsigned w, unsigned h, LodePNGColorType colortype, unsigned bitdepth) { - size_t bpp = lodepng_get_bpp_lct(colortype, bitdepth); - size_t n = (size_t)w * (size_t)h; - return ((n / 8u) * bpp) + ((n & 7u) * bpp + 7u) / 8u; -} - -size_t lodepng_get_raw_size(unsigned w, unsigned h, const LodePNGColorMode* color) { - return lodepng_get_raw_size_lct(w, h, color->colortype, color->bitdepth); -} - - -#ifdef LODEPNG_COMPILE_PNG - -/*in an idat chunk, each scanline is a multiple of 8 bits, unlike the lodepng output buffer, -and in addition has one extra byte per line: the filter byte. So this gives a larger -result than lodepng_get_raw_size. Set h to 1 to get the size of 1 row including filter byte. */ -static size_t lodepng_get_raw_size_idat(unsigned w, unsigned h, unsigned bpp) { - /* + 1 for the filter byte, and possibly plus padding bits per line. */ - /* Ignoring casts, the expression is equal to (w * bpp + 7) / 8 + 1, but avoids overflow of w * bpp */ - size_t line = ((size_t)(w / 8u) * bpp) + 1u + ((w & 7u) * bpp + 7u) / 8u; - return (size_t)h * line; -} - -#ifdef LODEPNG_COMPILE_DECODER -/*Safely checks whether size_t overflow can be caused due to amount of pixels. -This check is overcautious rather than precise. If this check indicates no overflow, -you can safely compute in a size_t (but not an unsigned): --(size_t)w * (size_t)h * 8 --amount of bytes in IDAT (including filter, padding and Adam7 bytes) --amount of bytes in raw color model -Returns 1 if overflow possible, 0 if not. -*/ -static int lodepng_pixel_overflow(unsigned w, unsigned h, - const LodePNGColorMode* pngcolor, const LodePNGColorMode* rawcolor) { - size_t bpp = LODEPNG_MAX(lodepng_get_bpp(pngcolor), lodepng_get_bpp(rawcolor)); - size_t numpixels, total; - size_t line; /* bytes per line in worst case */ - - if(lodepng_mulofl((size_t)w, (size_t)h, &numpixels)) return 1; - if(lodepng_mulofl(numpixels, 8, &total)) return 1; /* bit pointer with 8-bit color, or 8 bytes per channel color */ - - /* Bytes per scanline with the expression "(w / 8u) * bpp) + ((w & 7u) * bpp + 7u) / 8u" */ - if(lodepng_mulofl((size_t)(w / 8u), bpp, &line)) return 1; - if(lodepng_addofl(line, ((w & 7u) * bpp + 7u) / 8u, &line)) return 1; - - if(lodepng_addofl(line, 5, &line)) return 1; /* 5 bytes overhead per line: 1 filterbyte, 4 for Adam7 worst case */ - if(lodepng_mulofl(line, h, &total)) return 1; /* Total bytes in worst case */ - - return 0; /* no overflow */ -} -#endif /*LODEPNG_COMPILE_DECODER*/ -#endif /*LODEPNG_COMPILE_PNG*/ - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - -static void LodePNGUnknownChunks_init(LodePNGInfo* info) { - unsigned i; - for(i = 0; i != 3; ++i) info->unknown_chunks_data[i] = 0; - for(i = 0; i != 3; ++i) info->unknown_chunks_size[i] = 0; -} - -static void LodePNGUnknownChunks_cleanup(LodePNGInfo* info) { - unsigned i; - for(i = 0; i != 3; ++i) lodepng_free(info->unknown_chunks_data[i]); -} - -static unsigned LodePNGUnknownChunks_copy(LodePNGInfo* dest, const LodePNGInfo* src) { - unsigned i; - - LodePNGUnknownChunks_cleanup(dest); - - for(i = 0; i != 3; ++i) { - size_t j; - dest->unknown_chunks_size[i] = src->unknown_chunks_size[i]; - dest->unknown_chunks_data[i] = (unsigned char*)lodepng_malloc(src->unknown_chunks_size[i]); - if(!dest->unknown_chunks_data[i] && dest->unknown_chunks_size[i]) return 83; /*alloc fail*/ - for(j = 0; j < src->unknown_chunks_size[i]; ++j) { - dest->unknown_chunks_data[i][j] = src->unknown_chunks_data[i][j]; - } - } - - return 0; -} - -/******************************************************************************/ - -static void LodePNGText_init(LodePNGInfo* info) { - info->text_num = 0; - info->text_keys = NULL; - info->text_strings = NULL; -} - -static void LodePNGText_cleanup(LodePNGInfo* info) { - size_t i; - for(i = 0; i != info->text_num; ++i) { - string_cleanup(&info->text_keys[i]); - string_cleanup(&info->text_strings[i]); - } - lodepng_free(info->text_keys); - lodepng_free(info->text_strings); -} - -static unsigned LodePNGText_copy(LodePNGInfo* dest, const LodePNGInfo* source) { - size_t i = 0; - dest->text_keys = NULL; - dest->text_strings = NULL; - dest->text_num = 0; - for(i = 0; i != source->text_num; ++i) { - CERROR_TRY_RETURN(lodepng_add_text(dest, source->text_keys[i], source->text_strings[i])); - } - return 0; -} - -static unsigned lodepng_add_text_sized(LodePNGInfo* info, const char* key, const char* str, size_t size) { - char** new_keys = (char**)(lodepng_realloc(info->text_keys, sizeof(char*) * (info->text_num + 1))); - char** new_strings = (char**)(lodepng_realloc(info->text_strings, sizeof(char*) * (info->text_num + 1))); - - if(new_keys) info->text_keys = new_keys; - if(new_strings) info->text_strings = new_strings; - - if(!new_keys || !new_strings) return 83; /*alloc fail*/ - - ++info->text_num; - info->text_keys[info->text_num - 1] = alloc_string(key); - info->text_strings[info->text_num - 1] = alloc_string_sized(str, size); - if(!info->text_keys[info->text_num - 1] || !info->text_strings[info->text_num - 1]) return 83; /*alloc fail*/ - - return 0; -} - -unsigned lodepng_add_text(LodePNGInfo* info, const char* key, const char* str) { - return lodepng_add_text_sized(info, key, str, lodepng_strlen(str)); -} - -void lodepng_clear_text(LodePNGInfo* info) { - LodePNGText_cleanup(info); -} - -/******************************************************************************/ - -static void LodePNGIText_init(LodePNGInfo* info) { - info->itext_num = 0; - info->itext_keys = NULL; - info->itext_langtags = NULL; - info->itext_transkeys = NULL; - info->itext_strings = NULL; -} - -static void LodePNGIText_cleanup(LodePNGInfo* info) { - size_t i; - for(i = 0; i != info->itext_num; ++i) { - string_cleanup(&info->itext_keys[i]); - string_cleanup(&info->itext_langtags[i]); - string_cleanup(&info->itext_transkeys[i]); - string_cleanup(&info->itext_strings[i]); - } - lodepng_free(info->itext_keys); - lodepng_free(info->itext_langtags); - lodepng_free(info->itext_transkeys); - lodepng_free(info->itext_strings); -} - -static unsigned LodePNGIText_copy(LodePNGInfo* dest, const LodePNGInfo* source) { - size_t i = 0; - dest->itext_keys = NULL; - dest->itext_langtags = NULL; - dest->itext_transkeys = NULL; - dest->itext_strings = NULL; - dest->itext_num = 0; - for(i = 0; i != source->itext_num; ++i) { - CERROR_TRY_RETURN(lodepng_add_itext(dest, source->itext_keys[i], source->itext_langtags[i], - source->itext_transkeys[i], source->itext_strings[i])); - } - return 0; -} - -void lodepng_clear_itext(LodePNGInfo* info) { - LodePNGIText_cleanup(info); -} - -static unsigned lodepng_add_itext_sized(LodePNGInfo* info, const char* key, const char* langtag, - const char* transkey, const char* str, size_t size) { - char** new_keys = (char**)(lodepng_realloc(info->itext_keys, sizeof(char*) * (info->itext_num + 1))); - char** new_langtags = (char**)(lodepng_realloc(info->itext_langtags, sizeof(char*) * (info->itext_num + 1))); - char** new_transkeys = (char**)(lodepng_realloc(info->itext_transkeys, sizeof(char*) * (info->itext_num + 1))); - char** new_strings = (char**)(lodepng_realloc(info->itext_strings, sizeof(char*) * (info->itext_num + 1))); - - if(new_keys) info->itext_keys = new_keys; - if(new_langtags) info->itext_langtags = new_langtags; - if(new_transkeys) info->itext_transkeys = new_transkeys; - if(new_strings) info->itext_strings = new_strings; - - if(!new_keys || !new_langtags || !new_transkeys || !new_strings) return 83; /*alloc fail*/ - - ++info->itext_num; - - info->itext_keys[info->itext_num - 1] = alloc_string(key); - info->itext_langtags[info->itext_num - 1] = alloc_string(langtag); - info->itext_transkeys[info->itext_num - 1] = alloc_string(transkey); - info->itext_strings[info->itext_num - 1] = alloc_string_sized(str, size); - - return 0; -} - -unsigned lodepng_add_itext(LodePNGInfo* info, const char* key, const char* langtag, - const char* transkey, const char* str) { - return lodepng_add_itext_sized(info, key, langtag, transkey, str, lodepng_strlen(str)); -} - -/* same as set but does not delete */ -static unsigned lodepng_assign_icc(LodePNGInfo* info, const char* name, const unsigned char* profile, unsigned profile_size) { - if(profile_size == 0) return 100; /*invalid ICC profile size*/ - - info->iccp_name = alloc_string(name); - info->iccp_profile = (unsigned char*)lodepng_malloc(profile_size); - - if(!info->iccp_name || !info->iccp_profile) return 83; /*alloc fail*/ - - lodepng_memcpy(info->iccp_profile, profile, profile_size); - info->iccp_profile_size = profile_size; - - return 0; /*ok*/ -} - -unsigned lodepng_set_icc(LodePNGInfo* info, const char* name, const unsigned char* profile, unsigned profile_size) { - if(info->iccp_name) lodepng_clear_icc(info); - info->iccp_defined = 1; - - return lodepng_assign_icc(info, name, profile, profile_size); -} - -void lodepng_clear_icc(LodePNGInfo* info) { - string_cleanup(&info->iccp_name); - lodepng_free(info->iccp_profile); - info->iccp_profile = NULL; - info->iccp_profile_size = 0; - info->iccp_defined = 0; -} -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - -void lodepng_info_init(LodePNGInfo* info) { - lodepng_color_mode_init(&info->color); - info->interlace_method = 0; - info->compression_method = 0; - info->filter_method = 0; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - info->background_defined = 0; - info->background_r = info->background_g = info->background_b = 0; - - LodePNGText_init(info); - LodePNGIText_init(info); - - info->time_defined = 0; - info->phys_defined = 0; - - info->gama_defined = 0; - info->chrm_defined = 0; - info->srgb_defined = 0; - info->iccp_defined = 0; - info->iccp_name = NULL; - info->iccp_profile = NULL; - - info->sbit_defined = 0; - info->sbit_r = info->sbit_g = info->sbit_b = info->sbit_a = 0; - - LodePNGUnknownChunks_init(info); -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -} - -void lodepng_info_cleanup(LodePNGInfo* info) { - lodepng_color_mode_cleanup(&info->color); -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - LodePNGText_cleanup(info); - LodePNGIText_cleanup(info); - - lodepng_clear_icc(info); - - LodePNGUnknownChunks_cleanup(info); -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -} - -unsigned lodepng_info_copy(LodePNGInfo* dest, const LodePNGInfo* source) { - lodepng_info_cleanup(dest); - lodepng_memcpy(dest, source, sizeof(LodePNGInfo)); - lodepng_color_mode_init(&dest->color); - CERROR_TRY_RETURN(lodepng_color_mode_copy(&dest->color, &source->color)); - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - CERROR_TRY_RETURN(LodePNGText_copy(dest, source)); - CERROR_TRY_RETURN(LodePNGIText_copy(dest, source)); - if(source->iccp_defined) { - CERROR_TRY_RETURN(lodepng_assign_icc(dest, source->iccp_name, source->iccp_profile, source->iccp_profile_size)); - } - - LodePNGUnknownChunks_init(dest); - CERROR_TRY_RETURN(LodePNGUnknownChunks_copy(dest, source)); -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - return 0; -} - -/* ////////////////////////////////////////////////////////////////////////// */ - -/*index: bitgroup index, bits: bitgroup size(1, 2 or 4), in: bitgroup value, out: octet array to add bits to*/ -static void addColorBits(unsigned char* out, size_t index, unsigned bits, unsigned in) { - unsigned m = bits == 1 ? 7 : bits == 2 ? 3 : 1; /*8 / bits - 1*/ - /*p = the partial index in the byte, e.g. with 4 palettebits it is 0 for first half or 1 for second half*/ - unsigned p = index & m; - in &= (1u << bits) - 1u; /*filter out any other bits of the input value*/ - in = in << (bits * (m - p)); - if(p == 0) out[index * bits / 8u] = in; - else out[index * bits / 8u] |= in; -} - -typedef struct ColorTree ColorTree; - -/* -One node of a color tree -This is the data structure used to count the number of unique colors and to get a palette -index for a color. It's like an octree, but because the alpha channel is used too, each -node has 16 instead of 8 children. -*/ -struct ColorTree { - ColorTree* children[16]; /*up to 16 pointers to ColorTree of next level*/ - int index; /*the payload. Only has a meaningful value if this is in the last level*/ -}; - -static void color_tree_init(ColorTree* tree) { - lodepng_memset(tree->children, 0, 16 * sizeof(*tree->children)); - tree->index = -1; -} - -static void color_tree_cleanup(ColorTree* tree) { - int i; - for(i = 0; i != 16; ++i) { - if(tree->children[i]) { - color_tree_cleanup(tree->children[i]); - lodepng_free(tree->children[i]); - } - } -} - -/*returns -1 if color not present, its index otherwise*/ -static int color_tree_get(ColorTree* tree, unsigned char r, unsigned char g, unsigned char b, unsigned char a) { - int bit = 0; - for(bit = 0; bit < 8; ++bit) { - int i = 8 * ((r >> bit) & 1) + 4 * ((g >> bit) & 1) + 2 * ((b >> bit) & 1) + 1 * ((a >> bit) & 1); - if(!tree->children[i]) return -1; - else tree = tree->children[i]; - } - return tree ? tree->index : -1; -} - -#ifdef LODEPNG_COMPILE_ENCODER -static int color_tree_has(ColorTree* tree, unsigned char r, unsigned char g, unsigned char b, unsigned char a) { - return color_tree_get(tree, r, g, b, a) >= 0; -} -#endif /*LODEPNG_COMPILE_ENCODER*/ - -/*color is not allowed to already exist. -Index should be >= 0 (it's signed to be compatible with using -1 for "doesn't exist") -Returns error code, or 0 if ok*/ -static unsigned color_tree_add(ColorTree* tree, - unsigned char r, unsigned char g, unsigned char b, unsigned char a, unsigned index) { - int bit; - for(bit = 0; bit < 8; ++bit) { - int i = 8 * ((r >> bit) & 1) + 4 * ((g >> bit) & 1) + 2 * ((b >> bit) & 1) + 1 * ((a >> bit) & 1); - if(!tree->children[i]) { - tree->children[i] = (ColorTree*)lodepng_malloc(sizeof(ColorTree)); - if(!tree->children[i]) return 83; /*alloc fail*/ - color_tree_init(tree->children[i]); - } - tree = tree->children[i]; - } - tree->index = (int)index; - return 0; -} - -/*put a pixel, given its RGBA color, into image of any color type*/ -static unsigned rgba8ToPixel(unsigned char* out, size_t i, - const LodePNGColorMode* mode, ColorTree* tree /*for palette*/, - unsigned char r, unsigned char g, unsigned char b, unsigned char a) { - if(mode->colortype == LCT_GREY) { - unsigned char gray = r; /*((unsigned short)r + g + b) / 3u;*/ - if(mode->bitdepth == 8) out[i] = gray; - else if(mode->bitdepth == 16) out[i * 2 + 0] = out[i * 2 + 1] = gray; - else { - /*take the most significant bits of gray*/ - gray = ((unsigned)gray >> (8u - mode->bitdepth)) & ((1u << mode->bitdepth) - 1u); - addColorBits(out, i, mode->bitdepth, gray); - } - } else if(mode->colortype == LCT_RGB) { - if(mode->bitdepth == 8) { - out[i * 3 + 0] = r; - out[i * 3 + 1] = g; - out[i * 3 + 2] = b; - } else { - out[i * 6 + 0] = out[i * 6 + 1] = r; - out[i * 6 + 2] = out[i * 6 + 3] = g; - out[i * 6 + 4] = out[i * 6 + 5] = b; - } - } else if(mode->colortype == LCT_PALETTE) { - int index = color_tree_get(tree, r, g, b, a); - if(index < 0) return 82; /*color not in palette*/ - if(mode->bitdepth == 8) out[i] = index; - else addColorBits(out, i, mode->bitdepth, (unsigned)index); - } else if(mode->colortype == LCT_GREY_ALPHA) { - unsigned char gray = r; /*((unsigned short)r + g + b) / 3u;*/ - if(mode->bitdepth == 8) { - out[i * 2 + 0] = gray; - out[i * 2 + 1] = a; - } else if(mode->bitdepth == 16) { - out[i * 4 + 0] = out[i * 4 + 1] = gray; - out[i * 4 + 2] = out[i * 4 + 3] = a; - } - } else if(mode->colortype == LCT_RGBA) { - if(mode->bitdepth == 8) { - out[i * 4 + 0] = r; - out[i * 4 + 1] = g; - out[i * 4 + 2] = b; - out[i * 4 + 3] = a; - } else { - out[i * 8 + 0] = out[i * 8 + 1] = r; - out[i * 8 + 2] = out[i * 8 + 3] = g; - out[i * 8 + 4] = out[i * 8 + 5] = b; - out[i * 8 + 6] = out[i * 8 + 7] = a; - } - } - - return 0; /*no error*/ -} - -/*put a pixel, given its RGBA16 color, into image of any color 16-bitdepth type*/ -static void rgba16ToPixel(unsigned char* out, size_t i, - const LodePNGColorMode* mode, - unsigned short r, unsigned short g, unsigned short b, unsigned short a) { - if(mode->colortype == LCT_GREY) { - unsigned short gray = r; /*((unsigned)r + g + b) / 3u;*/ - out[i * 2 + 0] = (gray >> 8) & 255; - out[i * 2 + 1] = gray & 255; - } else if(mode->colortype == LCT_RGB) { - out[i * 6 + 0] = (r >> 8) & 255; - out[i * 6 + 1] = r & 255; - out[i * 6 + 2] = (g >> 8) & 255; - out[i * 6 + 3] = g & 255; - out[i * 6 + 4] = (b >> 8) & 255; - out[i * 6 + 5] = b & 255; - } else if(mode->colortype == LCT_GREY_ALPHA) { - unsigned short gray = r; /*((unsigned)r + g + b) / 3u;*/ - out[i * 4 + 0] = (gray >> 8) & 255; - out[i * 4 + 1] = gray & 255; - out[i * 4 + 2] = (a >> 8) & 255; - out[i * 4 + 3] = a & 255; - } else if(mode->colortype == LCT_RGBA) { - out[i * 8 + 0] = (r >> 8) & 255; - out[i * 8 + 1] = r & 255; - out[i * 8 + 2] = (g >> 8) & 255; - out[i * 8 + 3] = g & 255; - out[i * 8 + 4] = (b >> 8) & 255; - out[i * 8 + 5] = b & 255; - out[i * 8 + 6] = (a >> 8) & 255; - out[i * 8 + 7] = a & 255; - } -} - -/*Get RGBA8 color of pixel with index i (y * width + x) from the raw image with given color type.*/ -static void getPixelColorRGBA8(unsigned char* r, unsigned char* g, - unsigned char* b, unsigned char* a, - const unsigned char* in, size_t i, - const LodePNGColorMode* mode) { - if(mode->colortype == LCT_GREY) { - if(mode->bitdepth == 8) { - *r = *g = *b = in[i]; - if(mode->key_defined && *r == mode->key_r) *a = 0; - else *a = 255; - } else if(mode->bitdepth == 16) { - *r = *g = *b = in[i * 2 + 0]; - if(mode->key_defined && 256U * in[i * 2 + 0] + in[i * 2 + 1] == mode->key_r) *a = 0; - else *a = 255; - } else { - unsigned highest = ((1U << mode->bitdepth) - 1U); /*highest possible value for this bit depth*/ - size_t j = i * mode->bitdepth; - unsigned value = readBitsFromReversedStream(&j, in, mode->bitdepth); - *r = *g = *b = (value * 255) / highest; - if(mode->key_defined && value == mode->key_r) *a = 0; - else *a = 255; - } - } else if(mode->colortype == LCT_RGB) { - if(mode->bitdepth == 8) { - *r = in[i * 3 + 0]; *g = in[i * 3 + 1]; *b = in[i * 3 + 2]; - if(mode->key_defined && *r == mode->key_r && *g == mode->key_g && *b == mode->key_b) *a = 0; - else *a = 255; - } else { - *r = in[i * 6 + 0]; - *g = in[i * 6 + 2]; - *b = in[i * 6 + 4]; - if(mode->key_defined && 256U * in[i * 6 + 0] + in[i * 6 + 1] == mode->key_r - && 256U * in[i * 6 + 2] + in[i * 6 + 3] == mode->key_g - && 256U * in[i * 6 + 4] + in[i * 6 + 5] == mode->key_b) *a = 0; - else *a = 255; - } - } else if(mode->colortype == LCT_PALETTE) { - unsigned index; - if(mode->bitdepth == 8) index = in[i]; - else { - size_t j = i * mode->bitdepth; - index = readBitsFromReversedStream(&j, in, mode->bitdepth); - } - /*out of bounds of palette not checked: see lodepng_color_mode_alloc_palette.*/ - *r = mode->palette[index * 4 + 0]; - *g = mode->palette[index * 4 + 1]; - *b = mode->palette[index * 4 + 2]; - *a = mode->palette[index * 4 + 3]; - } else if(mode->colortype == LCT_GREY_ALPHA) { - if(mode->bitdepth == 8) { - *r = *g = *b = in[i * 2 + 0]; - *a = in[i * 2 + 1]; - } else { - *r = *g = *b = in[i * 4 + 0]; - *a = in[i * 4 + 2]; - } - } else if(mode->colortype == LCT_RGBA) { - if(mode->bitdepth == 8) { - *r = in[i * 4 + 0]; - *g = in[i * 4 + 1]; - *b = in[i * 4 + 2]; - *a = in[i * 4 + 3]; - } else { - *r = in[i * 8 + 0]; - *g = in[i * 8 + 2]; - *b = in[i * 8 + 4]; - *a = in[i * 8 + 6]; - } - } -} - -/*Similar to getPixelColorRGBA8, but with all the for loops inside of the color -mode test cases, optimized to convert the colors much faster, when converting -to the common case of RGBA with 8 bit per channel. buffer must be RGBA with -enough memory.*/ -static void getPixelColorsRGBA8(unsigned char* LODEPNG_RESTRICT buffer, size_t numpixels, - const unsigned char* LODEPNG_RESTRICT in, - const LodePNGColorMode* mode) { - unsigned num_channels = 4; - size_t i; - if(mode->colortype == LCT_GREY) { - if(mode->bitdepth == 8) { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - buffer[0] = buffer[1] = buffer[2] = in[i]; - buffer[3] = 255; - } - if(mode->key_defined) { - buffer -= numpixels * num_channels; - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - if(buffer[0] == mode->key_r) buffer[3] = 0; - } - } - } else if(mode->bitdepth == 16) { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - buffer[0] = buffer[1] = buffer[2] = in[i * 2]; - buffer[3] = mode->key_defined && 256U * in[i * 2 + 0] + in[i * 2 + 1] == mode->key_r ? 0 : 255; - } - } else { - unsigned highest = ((1U << mode->bitdepth) - 1U); /*highest possible value for this bit depth*/ - size_t j = 0; - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - unsigned value = readBitsFromReversedStream(&j, in, mode->bitdepth); - buffer[0] = buffer[1] = buffer[2] = (value * 255) / highest; - buffer[3] = mode->key_defined && value == mode->key_r ? 0 : 255; - } - } - } else if(mode->colortype == LCT_RGB) { - if(mode->bitdepth == 8) { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - lodepng_memcpy(buffer, &in[i * 3], 3); - buffer[3] = 255; - } - if(mode->key_defined) { - buffer -= numpixels * num_channels; - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - if(buffer[0] == mode->key_r && buffer[1]== mode->key_g && buffer[2] == mode->key_b) buffer[3] = 0; - } - } - } else { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - buffer[0] = in[i * 6 + 0]; - buffer[1] = in[i * 6 + 2]; - buffer[2] = in[i * 6 + 4]; - buffer[3] = mode->key_defined - && 256U * in[i * 6 + 0] + in[i * 6 + 1] == mode->key_r - && 256U * in[i * 6 + 2] + in[i * 6 + 3] == mode->key_g - && 256U * in[i * 6 + 4] + in[i * 6 + 5] == mode->key_b ? 0 : 255; - } - } - } else if(mode->colortype == LCT_PALETTE) { - if(mode->bitdepth == 8) { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - unsigned index = in[i]; - /*out of bounds of palette not checked: see lodepng_color_mode_alloc_palette.*/ - lodepng_memcpy(buffer, &mode->palette[index * 4], 4); - } - } else { - size_t j = 0; - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - unsigned index = readBitsFromReversedStream(&j, in, mode->bitdepth); - /*out of bounds of palette not checked: see lodepng_color_mode_alloc_palette.*/ - lodepng_memcpy(buffer, &mode->palette[index * 4], 4); - } - } - } else if(mode->colortype == LCT_GREY_ALPHA) { - if(mode->bitdepth == 8) { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - buffer[0] = buffer[1] = buffer[2] = in[i * 2 + 0]; - buffer[3] = in[i * 2 + 1]; - } - } else { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - buffer[0] = buffer[1] = buffer[2] = in[i * 4 + 0]; - buffer[3] = in[i * 4 + 2]; - } - } - } else if(mode->colortype == LCT_RGBA) { - if(mode->bitdepth == 8) { - lodepng_memcpy(buffer, in, numpixels * 4); - } else { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - buffer[0] = in[i * 8 + 0]; - buffer[1] = in[i * 8 + 2]; - buffer[2] = in[i * 8 + 4]; - buffer[3] = in[i * 8 + 6]; - } - } - } -} - -/*Similar to getPixelColorsRGBA8, but with 3-channel RGB output.*/ -static void getPixelColorsRGB8(unsigned char* LODEPNG_RESTRICT buffer, size_t numpixels, - const unsigned char* LODEPNG_RESTRICT in, - const LodePNGColorMode* mode) { - const unsigned num_channels = 3; - size_t i; - if(mode->colortype == LCT_GREY) { - if(mode->bitdepth == 8) { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - buffer[0] = buffer[1] = buffer[2] = in[i]; - } - } else if(mode->bitdepth == 16) { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - buffer[0] = buffer[1] = buffer[2] = in[i * 2]; - } - } else { - unsigned highest = ((1U << mode->bitdepth) - 1U); /*highest possible value for this bit depth*/ - size_t j = 0; - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - unsigned value = readBitsFromReversedStream(&j, in, mode->bitdepth); - buffer[0] = buffer[1] = buffer[2] = (value * 255) / highest; - } - } - } else if(mode->colortype == LCT_RGB) { - if(mode->bitdepth == 8) { - lodepng_memcpy(buffer, in, numpixels * 3); - } else { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - buffer[0] = in[i * 6 + 0]; - buffer[1] = in[i * 6 + 2]; - buffer[2] = in[i * 6 + 4]; - } - } - } else if(mode->colortype == LCT_PALETTE) { - if(mode->bitdepth == 8) { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - unsigned index = in[i]; - /*out of bounds of palette not checked: see lodepng_color_mode_alloc_palette.*/ - lodepng_memcpy(buffer, &mode->palette[index * 4], 3); - } - } else { - size_t j = 0; - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - unsigned index = readBitsFromReversedStream(&j, in, mode->bitdepth); - /*out of bounds of palette not checked: see lodepng_color_mode_alloc_palette.*/ - lodepng_memcpy(buffer, &mode->palette[index * 4], 3); - } - } - } else if(mode->colortype == LCT_GREY_ALPHA) { - if(mode->bitdepth == 8) { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - buffer[0] = buffer[1] = buffer[2] = in[i * 2 + 0]; - } - } else { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - buffer[0] = buffer[1] = buffer[2] = in[i * 4 + 0]; - } - } - } else if(mode->colortype == LCT_RGBA) { - if(mode->bitdepth == 8) { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - lodepng_memcpy(buffer, &in[i * 4], 3); - } - } else { - for(i = 0; i != numpixels; ++i, buffer += num_channels) { - buffer[0] = in[i * 8 + 0]; - buffer[1] = in[i * 8 + 2]; - buffer[2] = in[i * 8 + 4]; - } - } - } -} - -/*Get RGBA16 color of pixel with index i (y * width + x) from the raw image with -given color type, but the given color type must be 16-bit itself.*/ -static void getPixelColorRGBA16(unsigned short* r, unsigned short* g, unsigned short* b, unsigned short* a, - const unsigned char* in, size_t i, const LodePNGColorMode* mode) { - if(mode->colortype == LCT_GREY) { - *r = *g = *b = 256 * in[i * 2 + 0] + in[i * 2 + 1]; - if(mode->key_defined && 256U * in[i * 2 + 0] + in[i * 2 + 1] == mode->key_r) *a = 0; - else *a = 65535; - } else if(mode->colortype == LCT_RGB) { - *r = 256u * in[i * 6 + 0] + in[i * 6 + 1]; - *g = 256u * in[i * 6 + 2] + in[i * 6 + 3]; - *b = 256u * in[i * 6 + 4] + in[i * 6 + 5]; - if(mode->key_defined - && 256u * in[i * 6 + 0] + in[i * 6 + 1] == mode->key_r - && 256u * in[i * 6 + 2] + in[i * 6 + 3] == mode->key_g - && 256u * in[i * 6 + 4] + in[i * 6 + 5] == mode->key_b) *a = 0; - else *a = 65535; - } else if(mode->colortype == LCT_GREY_ALPHA) { - *r = *g = *b = 256u * in[i * 4 + 0] + in[i * 4 + 1]; - *a = 256u * in[i * 4 + 2] + in[i * 4 + 3]; - } else if(mode->colortype == LCT_RGBA) { - *r = 256u * in[i * 8 + 0] + in[i * 8 + 1]; - *g = 256u * in[i * 8 + 2] + in[i * 8 + 3]; - *b = 256u * in[i * 8 + 4] + in[i * 8 + 5]; - *a = 256u * in[i * 8 + 6] + in[i * 8 + 7]; - } -} - -unsigned lodepng_convert(unsigned char* out, const unsigned char* in, - const LodePNGColorMode* mode_out, const LodePNGColorMode* mode_in, - unsigned w, unsigned h) { - size_t i; - ColorTree tree; - size_t numpixels = (size_t)w * (size_t)h; - unsigned error = 0; - - if(mode_in->colortype == LCT_PALETTE && !mode_in->palette) { - return 107; /* error: must provide palette if input mode is palette */ - } - - if(lodepng_color_mode_equal(mode_out, mode_in)) { - size_t numbytes = lodepng_get_raw_size(w, h, mode_in); - lodepng_memcpy(out, in, numbytes); - return 0; - } - - if(mode_out->colortype == LCT_PALETTE) { - size_t palettesize = mode_out->palettesize; - const unsigned char* palette = mode_out->palette; - size_t palsize = (size_t)1u << mode_out->bitdepth; - /*if the user specified output palette but did not give the values, assume - they want the values of the input color type (assuming that one is palette). - Note that we never create a new palette ourselves.*/ - if(palettesize == 0) { - palettesize = mode_in->palettesize; - palette = mode_in->palette; - /*if the input was also palette with same bitdepth, then the color types are also - equal, so copy literally. This to preserve the exact indices that were in the PNG - even in case there are duplicate colors in the palette.*/ - if(mode_in->colortype == LCT_PALETTE && mode_in->bitdepth == mode_out->bitdepth) { - size_t numbytes = lodepng_get_raw_size(w, h, mode_in); - lodepng_memcpy(out, in, numbytes); - return 0; - } - } - if(palettesize < palsize) palsize = palettesize; - color_tree_init(&tree); - for(i = 0; i != palsize; ++i) { - const unsigned char* p = &palette[i * 4]; - error = color_tree_add(&tree, p[0], p[1], p[2], p[3], (unsigned)i); - if(error) break; - } - } - - if(!error) { - if(mode_in->bitdepth == 16 && mode_out->bitdepth == 16) { - for(i = 0; i != numpixels; ++i) { - unsigned short r = 0, g = 0, b = 0, a = 0; - getPixelColorRGBA16(&r, &g, &b, &a, in, i, mode_in); - rgba16ToPixel(out, i, mode_out, r, g, b, a); - } - } else if(mode_out->bitdepth == 8 && mode_out->colortype == LCT_RGBA) { - getPixelColorsRGBA8(out, numpixels, in, mode_in); - } else if(mode_out->bitdepth == 8 && mode_out->colortype == LCT_RGB) { - getPixelColorsRGB8(out, numpixels, in, mode_in); - } else { - unsigned char r = 0, g = 0, b = 0, a = 0; - for(i = 0; i != numpixels; ++i) { - getPixelColorRGBA8(&r, &g, &b, &a, in, i, mode_in); - error = rgba8ToPixel(out, i, mode_out, &tree, r, g, b, a); - if(error) break; - } - } - } - - if(mode_out->colortype == LCT_PALETTE) { - color_tree_cleanup(&tree); - } - - return error; -} - - -/* Converts a single rgb color without alpha from one type to another, color bits truncated to -their bitdepth. In case of single channel (gray or palette), only the r channel is used. Slow -function, do not use to process all pixels of an image. Alpha channel not supported on purpose: -this is for bKGD, supporting alpha may prevent it from finding a color in the palette, from the -specification it looks like bKGD should ignore the alpha values of the palette since it can use -any palette index but doesn't have an alpha channel. Idem with ignoring color key. */ -unsigned lodepng_convert_rgb( - unsigned* r_out, unsigned* g_out, unsigned* b_out, - unsigned r_in, unsigned g_in, unsigned b_in, - const LodePNGColorMode* mode_out, const LodePNGColorMode* mode_in) { - unsigned r = 0, g = 0, b = 0; - unsigned mul = 65535 / ((1u << mode_in->bitdepth) - 1u); /*65535, 21845, 4369, 257, 1*/ - unsigned shift = 16 - mode_out->bitdepth; - - if(mode_in->colortype == LCT_GREY || mode_in->colortype == LCT_GREY_ALPHA) { - r = g = b = r_in * mul; - } else if(mode_in->colortype == LCT_RGB || mode_in->colortype == LCT_RGBA) { - r = r_in * mul; - g = g_in * mul; - b = b_in * mul; - } else if(mode_in->colortype == LCT_PALETTE) { - if(r_in >= mode_in->palettesize) return 82; - r = mode_in->palette[r_in * 4 + 0] * 257u; - g = mode_in->palette[r_in * 4 + 1] * 257u; - b = mode_in->palette[r_in * 4 + 2] * 257u; - } else { - return 31; - } - - /* now convert to output format */ - if(mode_out->colortype == LCT_GREY || mode_out->colortype == LCT_GREY_ALPHA) { - *r_out = r >> shift ; - } else if(mode_out->colortype == LCT_RGB || mode_out->colortype == LCT_RGBA) { - *r_out = r >> shift ; - *g_out = g >> shift ; - *b_out = b >> shift ; - } else if(mode_out->colortype == LCT_PALETTE) { - unsigned i; - /* a 16-bit color cannot be in the palette */ - if((r >> 8) != (r & 255) || (g >> 8) != (g & 255) || (b >> 8) != (b & 255)) return 82; - for(i = 0; i < mode_out->palettesize; i++) { - unsigned j = i * 4; - if((r >> 8) == mode_out->palette[j + 0] && (g >> 8) == mode_out->palette[j + 1] && - (b >> 8) == mode_out->palette[j + 2]) { - *r_out = i; - return 0; - } - } - return 82; - } else { - return 31; - } - - return 0; -} - -#ifdef LODEPNG_COMPILE_ENCODER - -void lodepng_color_stats_init(LodePNGColorStats* stats) { - /*stats*/ - stats->colored = 0; - stats->key = 0; - stats->key_r = stats->key_g = stats->key_b = 0; - stats->alpha = 0; - stats->numcolors = 0; - stats->bits = 1; - stats->numpixels = 0; - /*settings*/ - stats->allow_palette = 1; - stats->allow_greyscale = 1; -} - -/*function used for debug purposes with C++*/ -/*void printColorStats(LodePNGColorStats* p) { - std::cout << "colored: " << (int)p->colored << ", "; - std::cout << "key: " << (int)p->key << ", "; - std::cout << "key_r: " << (int)p->key_r << ", "; - std::cout << "key_g: " << (int)p->key_g << ", "; - std::cout << "key_b: " << (int)p->key_b << ", "; - std::cout << "alpha: " << (int)p->alpha << ", "; - std::cout << "numcolors: " << (int)p->numcolors << ", "; - std::cout << "bits: " << (int)p->bits << std::endl; -}*/ - -/*Returns how many bits needed to represent given value (max 8 bit)*/ -static unsigned getValueRequiredBits(unsigned char value) { - if(value == 0 || value == 255) return 1; - /*The scaling of 2-bit and 4-bit values uses multiples of 85 and 17*/ - if(value % 17 == 0) return value % 85 == 0 ? 2 : 4; - return 8; -} - -/*stats must already have been inited. */ -unsigned lodepng_compute_color_stats(LodePNGColorStats* stats, - const unsigned char* in, unsigned w, unsigned h, - const LodePNGColorMode* mode_in) { - size_t i; - ColorTree tree; - size_t numpixels = (size_t)w * (size_t)h; - unsigned error = 0; - - /* mark things as done already if it would be impossible to have a more expensive case */ - unsigned colored_done = lodepng_is_greyscale_type(mode_in) ? 1 : 0; - unsigned alpha_done = lodepng_can_have_alpha(mode_in) ? 0 : 1; - unsigned numcolors_done = 0; - unsigned bpp = lodepng_get_bpp(mode_in); - unsigned bits_done = (stats->bits == 1 && bpp == 1) ? 1 : 0; - unsigned sixteen = 0; /* whether the input image is 16 bit */ - unsigned maxnumcolors = 257; - if(bpp <= 8) maxnumcolors = LODEPNG_MIN(257, stats->numcolors + (1u << bpp)); - - stats->numpixels += numpixels; - - /*if palette not allowed, no need to compute numcolors*/ - if(!stats->allow_palette) numcolors_done = 1; - - color_tree_init(&tree); - - /*If the stats was already filled in from previous data, fill its palette in tree - and mark things as done already if we know they are the most expensive case already*/ - if(stats->alpha) alpha_done = 1; - if(stats->colored) colored_done = 1; - if(stats->bits == 16) numcolors_done = 1; - if(stats->bits >= bpp) bits_done = 1; - if(stats->numcolors >= maxnumcolors) numcolors_done = 1; - - if(!numcolors_done) { - for(i = 0; i < stats->numcolors; i++) { - const unsigned char* color = &stats->palette[i * 4]; - error = color_tree_add(&tree, color[0], color[1], color[2], color[3], i); - if(error) goto cleanup; - } - } - - /*Check if the 16-bit input is truly 16-bit*/ - if(mode_in->bitdepth == 16 && !sixteen) { - unsigned short r = 0, g = 0, b = 0, a = 0; - for(i = 0; i != numpixels; ++i) { - getPixelColorRGBA16(&r, &g, &b, &a, in, i, mode_in); - if((r & 255) != ((r >> 8) & 255) || (g & 255) != ((g >> 8) & 255) || - (b & 255) != ((b >> 8) & 255) || (a & 255) != ((a >> 8) & 255)) /*first and second byte differ*/ { - stats->bits = 16; - sixteen = 1; - bits_done = 1; - numcolors_done = 1; /*counting colors no longer useful, palette doesn't support 16-bit*/ - break; - } - } - } - - if(sixteen) { - unsigned short r = 0, g = 0, b = 0, a = 0; - - for(i = 0; i != numpixels; ++i) { - getPixelColorRGBA16(&r, &g, &b, &a, in, i, mode_in); - - if(!colored_done && (r != g || r != b)) { - stats->colored = 1; - colored_done = 1; - } - - if(!alpha_done) { - unsigned matchkey = (r == stats->key_r && g == stats->key_g && b == stats->key_b); - if(a != 65535 && (a != 0 || (stats->key && !matchkey))) { - stats->alpha = 1; - stats->key = 0; - alpha_done = 1; - } else if(a == 0 && !stats->alpha && !stats->key) { - stats->key = 1; - stats->key_r = r; - stats->key_g = g; - stats->key_b = b; - } else if(a == 65535 && stats->key && matchkey) { - /* Color key cannot be used if an opaque pixel also has that RGB color. */ - stats->alpha = 1; - stats->key = 0; - alpha_done = 1; - } - } - if(alpha_done && numcolors_done && colored_done && bits_done) break; - } - - if(stats->key && !stats->alpha) { - for(i = 0; i != numpixels; ++i) { - getPixelColorRGBA16(&r, &g, &b, &a, in, i, mode_in); - if(a != 0 && r == stats->key_r && g == stats->key_g && b == stats->key_b) { - /* Color key cannot be used if an opaque pixel also has that RGB color. */ - stats->alpha = 1; - stats->key = 0; - alpha_done = 1; - } - } - } - } else /* < 16-bit */ { - unsigned char r = 0, g = 0, b = 0, a = 0; - for(i = 0; i != numpixels; ++i) { - getPixelColorRGBA8(&r, &g, &b, &a, in, i, mode_in); - - if(!bits_done && stats->bits < 8) { - /*only r is checked, < 8 bits is only relevant for grayscale*/ - unsigned bits = getValueRequiredBits(r); - if(bits > stats->bits) stats->bits = bits; - } - bits_done = (stats->bits >= bpp); - - if(!colored_done && (r != g || r != b)) { - stats->colored = 1; - colored_done = 1; - if(stats->bits < 8) stats->bits = 8; /*PNG has no colored modes with less than 8-bit per channel*/ - } - - if(!alpha_done) { - unsigned matchkey = (r == stats->key_r && g == stats->key_g && b == stats->key_b); - if(a != 255 && (a != 0 || (stats->key && !matchkey))) { - stats->alpha = 1; - stats->key = 0; - alpha_done = 1; - if(stats->bits < 8) stats->bits = 8; /*PNG has no alphachannel modes with less than 8-bit per channel*/ - } else if(a == 0 && !stats->alpha && !stats->key) { - stats->key = 1; - stats->key_r = r; - stats->key_g = g; - stats->key_b = b; - } else if(a == 255 && stats->key && matchkey) { - /* Color key cannot be used if an opaque pixel also has that RGB color. */ - stats->alpha = 1; - stats->key = 0; - alpha_done = 1; - if(stats->bits < 8) stats->bits = 8; /*PNG has no alphachannel modes with less than 8-bit per channel*/ - } - } - - if(!numcolors_done) { - if(!color_tree_has(&tree, r, g, b, a)) { - error = color_tree_add(&tree, r, g, b, a, stats->numcolors); - if(error) goto cleanup; - if(stats->numcolors < 256) { - unsigned char* p = stats->palette; - unsigned n = stats->numcolors; - p[n * 4 + 0] = r; - p[n * 4 + 1] = g; - p[n * 4 + 2] = b; - p[n * 4 + 3] = a; - } - ++stats->numcolors; - numcolors_done = stats->numcolors >= maxnumcolors; - } - } - - if(alpha_done && numcolors_done && colored_done && bits_done) break; - } - - if(stats->key && !stats->alpha) { - for(i = 0; i != numpixels; ++i) { - getPixelColorRGBA8(&r, &g, &b, &a, in, i, mode_in); - if(a != 0 && r == stats->key_r && g == stats->key_g && b == stats->key_b) { - /* Color key cannot be used if an opaque pixel also has that RGB color. */ - stats->alpha = 1; - stats->key = 0; - alpha_done = 1; - if(stats->bits < 8) stats->bits = 8; /*PNG has no alphachannel modes with less than 8-bit per channel*/ - } - } - } - - /*make the stats's key always 16-bit for consistency - repeat each byte twice*/ - stats->key_r += (stats->key_r << 8); - stats->key_g += (stats->key_g << 8); - stats->key_b += (stats->key_b << 8); - } - -cleanup: - color_tree_cleanup(&tree); - return error; -} - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS -/*Adds a single color to the color stats. The stats must already have been inited. The color must be given as 16-bit -(with 2 bytes repeating for 8-bit and 65535 for opaque alpha channel). This function is expensive, do not call it for -all pixels of an image but only for a few additional values. */ -static unsigned lodepng_color_stats_add(LodePNGColorStats* stats, - unsigned r, unsigned g, unsigned b, unsigned a) { - unsigned error = 0; - unsigned char image[8]; - LodePNGColorMode mode; - lodepng_color_mode_init(&mode); - image[0] = r >> 8; image[1] = r; image[2] = g >> 8; image[3] = g; - image[4] = b >> 8; image[5] = b; image[6] = a >> 8; image[7] = a; - mode.bitdepth = 16; - mode.colortype = LCT_RGBA; - error = lodepng_compute_color_stats(stats, image, 1, 1, &mode); - lodepng_color_mode_cleanup(&mode); - return error; -} -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - -/*Computes a minimal PNG color model that can contain all colors as indicated by the stats. -The stats should be computed with lodepng_compute_color_stats. -mode_in is raw color profile of the image the stats were computed on, to copy palette order from when relevant. -Minimal PNG color model means the color type and bit depth that gives smallest amount of bits in the output image, -e.g. gray if only grayscale pixels, palette if less than 256 colors, color key if only single transparent color, ... -This is used if auto_convert is enabled (it is by default). -*/ -static unsigned auto_choose_color(LodePNGColorMode* mode_out, - const LodePNGColorMode* mode_in, - const LodePNGColorStats* stats) { - unsigned error = 0; - unsigned palettebits; - size_t i, n; - size_t numpixels = stats->numpixels; - unsigned palette_ok, gray_ok; - - unsigned alpha = stats->alpha; - unsigned key = stats->key; - unsigned bits = stats->bits; - - mode_out->key_defined = 0; - - if(key && numpixels <= 16) { - alpha = 1; /*too few pixels to justify tRNS chunk overhead*/ - key = 0; - if(bits < 8) bits = 8; /*PNG has no alphachannel modes with less than 8-bit per channel*/ - } - - gray_ok = !stats->colored; - if(!stats->allow_greyscale) gray_ok = 0; - if(!gray_ok && bits < 8) bits = 8; - - n = stats->numcolors; - palettebits = n <= 2 ? 1 : (n <= 4 ? 2 : (n <= 16 ? 4 : 8)); - palette_ok = n <= 256 && bits <= 8 && n != 0; /*n==0 means likely numcolors wasn't computed*/ - if(numpixels < n * 2) palette_ok = 0; /*don't add palette overhead if image has only a few pixels*/ - if(gray_ok && !alpha && bits <= palettebits) palette_ok = 0; /*gray is less overhead*/ - if(!stats->allow_palette) palette_ok = 0; - - if(palette_ok) { - const unsigned char* p = stats->palette; - lodepng_palette_clear(mode_out); /*remove potential earlier palette*/ - for(i = 0; i != stats->numcolors; ++i) { - error = lodepng_palette_add(mode_out, p[i * 4 + 0], p[i * 4 + 1], p[i * 4 + 2], p[i * 4 + 3]); - if(error) break; - } - - mode_out->colortype = LCT_PALETTE; - mode_out->bitdepth = palettebits; - - if(mode_in->colortype == LCT_PALETTE && mode_in->palettesize >= mode_out->palettesize - && mode_in->bitdepth == mode_out->bitdepth) { - /*If input should have same palette colors, keep original to preserve its order and prevent conversion*/ - lodepng_color_mode_cleanup(mode_out); /*clears palette, keeps the above set colortype and bitdepth fields as-is*/ - lodepng_color_mode_copy(mode_out, mode_in); - } - } else /*8-bit or 16-bit per channel*/ { - mode_out->bitdepth = bits; - mode_out->colortype = alpha ? (gray_ok ? LCT_GREY_ALPHA : LCT_RGBA) - : (gray_ok ? LCT_GREY : LCT_RGB); - if(key) { - unsigned mask = (1u << mode_out->bitdepth) - 1u; /*stats always uses 16-bit, mask converts it*/ - mode_out->key_r = stats->key_r & mask; - mode_out->key_g = stats->key_g & mask; - mode_out->key_b = stats->key_b & mask; - mode_out->key_defined = 1; - } - } - - return error; -} - -#endif /* #ifdef LODEPNG_COMPILE_ENCODER */ - -/*Paeth predictor, used by PNG filter type 4*/ -static unsigned char paethPredictor(unsigned char a, unsigned char b, unsigned char c) { - /* the subtractions of unsigned char cast it to a signed type. - With gcc, short is faster than int, with clang int is as fast (as of april 2023)*/ - short pa = (b - c) < 0 ? -(b - c) : (b - c); - short pb = (a - c) < 0 ? -(a - c) : (a - c); - /* writing it out like this compiles to something faster than introducing a temp variable*/ - short pc = (a + b - c - c) < 0 ? -(a + b - c - c) : (a + b - c - c); - /* return input value associated with smallest of pa, pb, pc (with certain priority if equal) */ - if(pb < pa) { a = b; pa = pb; } - return (pc < pa) ? c : a; -} - -/*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*/ - -/* -Outputs various dimensions and positions in the image related to the Adam7 reduced images. -passw: output containing the width of the 7 passes -passh: output containing the height of the 7 passes -filter_passstart: output containing the index of the start and end of each - reduced image with filter bytes -padded_passstart output containing the index of the start and end of each - reduced image when without filter bytes but with padded scanlines -passstart: output containing the index of the start and end of each reduced - image without padding between scanlines, but still padding between the images -w, h: width and height of non-interlaced image -bpp: bits per pixel -"padded" is only relevant if bpp is less than 8 and a scanline or image does not - end at a full byte -*/ -static void Adam7_getpassvalues(unsigned passw[7], unsigned passh[7], size_t filter_passstart[8], - size_t padded_passstart[8], size_t passstart[8], unsigned w, unsigned h, unsigned bpp) { - /*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] * (1u + (passw[i] * bpp + 7u) / 8u) : 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 + 7u) / 8u); - /*only padded at end of reduced image*/ - passstart[i + 1] = passstart[i] + (passh[i] * passw[i] * bpp + 7u) / 8u; - } -} - -#ifdef LODEPNG_COMPILE_DECODER - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / PNG Decoder / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -/*read the information from the header and store it in the LodePNGInfo. return value is error*/ -unsigned lodepng_inspect(unsigned* w, unsigned* h, LodePNGState* state, - const unsigned char* in, size_t insize) { - unsigned width, height; - LodePNGInfo* info = &state->info_png; - if(insize == 0 || in == 0) { - CERROR_RETURN_ERROR(state->error, 48); /*error: the given data is empty*/ - } - if(insize < 33) { - CERROR_RETURN_ERROR(state->error, 27); /*error: the data length is smaller than the length of a PNG header*/ - } - - /*when decoding a new PNG image, make sure all parameters created after previous decoding are reset*/ - /* TODO: remove this. One should use a new LodePNGState for new sessions */ - lodepng_info_cleanup(info); - lodepng_info_init(info); - - if(in[0] != 137 || in[1] != 80 || in[2] != 78 || in[3] != 71 - || in[4] != 13 || in[5] != 10 || in[6] != 26 || in[7] != 10) { - CERROR_RETURN_ERROR(state->error, 28); /*error: the first 8 bytes are not the correct PNG signature*/ - } - if(lodepng_chunk_length(in + 8) != 13) { - CERROR_RETURN_ERROR(state->error, 94); /*error: header size must be 13 bytes*/ - } - if(!lodepng_chunk_type_equals(in + 8, "IHDR")) { - CERROR_RETURN_ERROR(state->error, 29); /*error: it doesn't start with a IHDR chunk!*/ - } - - /*read the values given in the header*/ - width = lodepng_read32bitInt(&in[16]); - height = lodepng_read32bitInt(&in[20]); - /*TODO: remove the undocumented feature that allows to give null pointers to width or height*/ - if(w) *w = width; - if(h) *h = height; - info->color.bitdepth = in[24]; - info->color.colortype = (LodePNGColorType)in[25]; - info->compression_method = in[26]; - info->filter_method = in[27]; - info->interlace_method = in[28]; - - /*errors returned only after the parsing so other values are still output*/ - - /*error: invalid image size*/ - if(width == 0 || height == 0) CERROR_RETURN_ERROR(state->error, 93); - /*error: invalid colortype or bitdepth combination*/ - state->error = checkColorValidity(info->color.colortype, info->color.bitdepth); - if(state->error) return state->error; - /*error: only compression method 0 is allowed in the specification*/ - if(info->compression_method != 0) CERROR_RETURN_ERROR(state->error, 32); - /*error: only filter method 0 is allowed in the specification*/ - if(info->filter_method != 0) CERROR_RETURN_ERROR(state->error, 33); - /*error: only interlace methods 0 and 1 exist in the specification*/ - if(info->interlace_method > 1) CERROR_RETURN_ERROR(state->error, 34); - - if(!state->decoder.ignore_crc) { - unsigned CRC = lodepng_read32bitInt(&in[29]); - unsigned checksum = lodepng_crc32(&in[12], 17); - if(CRC != checksum) { - CERROR_RETURN_ERROR(state->error, 57); /*invalid CRC*/ - } - } - - return state->error; -} - -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: { - size_t j = 0; - for(i = 0; i != bytewidth; ++i) recon[i] = scanline[i]; - for(i = bytewidth; i != length; ++i, ++j) recon[i] = scanline[i] + recon[j]; - 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) { - size_t j = 0; - for(i = 0; i != bytewidth; ++i) recon[i] = scanline[i] + (precon[i] >> 1u); - /* Unroll independent paths of this predictor. A 6x and 8x version is also possible but that adds - too much code. Whether this speeds up anything depends on compiler and settings. */ - if(bytewidth >= 4) { - for(; i + 3 < length; i += 4, j += 4) { - unsigned char s0 = scanline[i + 0], s1 = scanline[i + 1], s2 = scanline[i + 2], s3 = scanline[i + 3]; - unsigned char r0 = recon[j + 0], r1 = recon[j + 1], r2 = recon[j + 2], r3 = recon[j + 3]; - unsigned char p0 = precon[i + 0], p1 = precon[i + 1], p2 = precon[i + 2], p3 = precon[i + 3]; - recon[i + 0] = s0 + ((r0 + p0) >> 1u); - recon[i + 1] = s1 + ((r1 + p1) >> 1u); - recon[i + 2] = s2 + ((r2 + p2) >> 1u); - recon[i + 3] = s3 + ((r3 + p3) >> 1u); - } - } else if(bytewidth >= 3) { - for(; i + 2 < length; i += 3, j += 3) { - unsigned char s0 = scanline[i + 0], s1 = scanline[i + 1], s2 = scanline[i + 2]; - unsigned char r0 = recon[j + 0], r1 = recon[j + 1], r2 = recon[j + 2]; - unsigned char p0 = precon[i + 0], p1 = precon[i + 1], p2 = precon[i + 2]; - recon[i + 0] = s0 + ((r0 + p0) >> 1u); - recon[i + 1] = s1 + ((r1 + p1) >> 1u); - recon[i + 2] = s2 + ((r2 + p2) >> 1u); - } - } else if(bytewidth >= 2) { - for(; i + 1 < length; i += 2, j += 2) { - unsigned char s0 = scanline[i + 0], s1 = scanline[i + 1]; - unsigned char r0 = recon[j + 0], r1 = recon[j + 1]; - unsigned char p0 = precon[i + 0], p1 = precon[i + 1]; - recon[i + 0] = s0 + ((r0 + p0) >> 1u); - recon[i + 1] = s1 + ((r1 + p1) >> 1u); - } - } - for(; i != length; ++i, ++j) recon[i] = scanline[i] + ((recon[j] + precon[i]) >> 1u); - } else { - size_t j = 0; - for(i = 0; i != bytewidth; ++i) recon[i] = scanline[i]; - for(i = bytewidth; i != length; ++i, ++j) recon[i] = scanline[i] + (recon[j] >> 1u); - } - break; - case 4: - if(precon) { - /* Unroll independent paths of this predictor. Whether this speeds up - anything depends on compiler and settings. */ - if(bytewidth == 8) { - unsigned char a0, b0 = 0, c0, d0 = 0, a1, b1 = 0, c1, d1 = 0; - unsigned char a2, b2 = 0, c2, d2 = 0, a3, b3 = 0, c3, d3 = 0; - unsigned char a4, b4 = 0, c4, d4 = 0, a5, b5 = 0, c5, d5 = 0; - unsigned char a6, b6 = 0, c6, d6 = 0, a7, b7 = 0, c7, d7 = 0; - for(i = 0; i + 7 < length; i += 8) { - c0 = b0; c1 = b1; c2 = b2; c3 = b3; - c4 = b4; c5 = b5; c6 = b6; c7 = b7; - b0 = precon[i + 0]; b1 = precon[i + 1]; b2 = precon[i + 2]; b3 = precon[i + 3]; - b4 = precon[i + 4]; b5 = precon[i + 5]; b6 = precon[i + 6]; b7 = precon[i + 7]; - a0 = d0; a1 = d1; a2 = d2; a3 = d3; - a4 = d4; a5 = d5; a6 = d6; a7 = d7; - d0 = scanline[i + 0] + paethPredictor(a0, b0, c0); - d1 = scanline[i + 1] + paethPredictor(a1, b1, c1); - d2 = scanline[i + 2] + paethPredictor(a2, b2, c2); - d3 = scanline[i + 3] + paethPredictor(a3, b3, c3); - d4 = scanline[i + 4] + paethPredictor(a4, b4, c4); - d5 = scanline[i + 5] + paethPredictor(a5, b5, c5); - d6 = scanline[i + 6] + paethPredictor(a6, b6, c6); - d7 = scanline[i + 7] + paethPredictor(a7, b7, c7); - recon[i + 0] = d0; recon[i + 1] = d1; recon[i + 2] = d2; recon[i + 3] = d3; - recon[i + 4] = d4; recon[i + 5] = d5; recon[i + 6] = d6; recon[i + 7] = d7; - } - } else if(bytewidth == 6) { - unsigned char a0, b0 = 0, c0, d0 = 0, a1, b1 = 0, c1, d1 = 0; - unsigned char a2, b2 = 0, c2, d2 = 0, a3, b3 = 0, c3, d3 = 0; - unsigned char a4, b4 = 0, c4, d4 = 0, a5, b5 = 0, c5, d5 = 0; - for(i = 0; i + 5 < length; i += 6) { - c0 = b0; c1 = b1; c2 = b2; - c3 = b3; c4 = b4; c5 = b5; - b0 = precon[i + 0]; b1 = precon[i + 1]; b2 = precon[i + 2]; - b3 = precon[i + 3]; b4 = precon[i + 4]; b5 = precon[i + 5]; - a0 = d0; a1 = d1; a2 = d2; - a3 = d3; a4 = d4; a5 = d5; - d0 = scanline[i + 0] + paethPredictor(a0, b0, c0); - d1 = scanline[i + 1] + paethPredictor(a1, b1, c1); - d2 = scanline[i + 2] + paethPredictor(a2, b2, c2); - d3 = scanline[i + 3] + paethPredictor(a3, b3, c3); - d4 = scanline[i + 4] + paethPredictor(a4, b4, c4); - d5 = scanline[i + 5] + paethPredictor(a5, b5, c5); - recon[i + 0] = d0; recon[i + 1] = d1; recon[i + 2] = d2; - recon[i + 3] = d3; recon[i + 4] = d4; recon[i + 5] = d5; - } - } else if(bytewidth == 4) { - unsigned char a0, b0 = 0, c0, d0 = 0, a1, b1 = 0, c1, d1 = 0; - unsigned char a2, b2 = 0, c2, d2 = 0, a3, b3 = 0, c3, d3 = 0; - for(i = 0; i + 3 < length; i += 4) { - c0 = b0; c1 = b1; c2 = b2; c3 = b3; - b0 = precon[i + 0]; b1 = precon[i + 1]; b2 = precon[i + 2]; b3 = precon[i + 3]; - a0 = d0; a1 = d1; a2 = d2; a3 = d3; - d0 = scanline[i + 0] + paethPredictor(a0, b0, c0); - d1 = scanline[i + 1] + paethPredictor(a1, b1, c1); - d2 = scanline[i + 2] + paethPredictor(a2, b2, c2); - d3 = scanline[i + 3] + paethPredictor(a3, b3, c3); - recon[i + 0] = d0; recon[i + 1] = d1; recon[i + 2] = d2; recon[i + 3] = d3; - } - } else if(bytewidth == 3) { - unsigned char a0, b0 = 0, c0, d0 = 0; - unsigned char a1, b1 = 0, c1, d1 = 0; - unsigned char a2, b2 = 0, c2, d2 = 0; - for(i = 0; i + 2 < length; i += 3) { - c0 = b0; c1 = b1; c2 = b2; - b0 = precon[i + 0]; b1 = precon[i + 1]; b2 = precon[i + 2]; - a0 = d0; a1 = d1; a2 = d2; - d0 = scanline[i + 0] + paethPredictor(a0, b0, c0); - d1 = scanline[i + 1] + paethPredictor(a1, b1, c1); - d2 = scanline[i + 2] + paethPredictor(a2, b2, c2); - recon[i + 0] = d0; recon[i + 1] = d1; recon[i + 2] = d2; - } - } else if(bytewidth == 2) { - unsigned char a0, b0 = 0, c0, d0 = 0; - unsigned char a1, b1 = 0, c1, d1 = 0; - for(i = 0; i + 1 < length; i += 2) { - c0 = b0; c1 = b1; - b0 = precon[i + 0]; - b1 = precon[i + 1]; - a0 = d0; a1 = d1; - d0 = scanline[i + 0] + paethPredictor(a0, b0, c0); - d1 = scanline[i + 1] + paethPredictor(a1, b1, c1); - recon[i + 0] = d0; - recon[i + 1] = d1; - } - } else if(bytewidth == 1) { - unsigned char a, b = 0, c, d = 0; - for(i = 0; i != length; ++i) { - c = b; - b = precon[i]; - a = d; - d = scanline[i] + paethPredictor(a, b, c); - recon[i] = d; - } - } else { - /* Normally not a possible case, but this would handle it correctly */ - for(i = 0; i != bytewidth; ++i) { - recon[i] = (scanline[i] + precon[i]); /*paethPredictor(0, precon[i], 0) is always precon[i]*/ - } - } - /* finish any remaining bytes */ - for(; i != length; ++i) { - recon[i] = (scanline[i] + paethPredictor(recon[i - bytewidth], precon[i], precon[i - bytewidth])); - } - } else { - size_t j = 0; - for(i = 0; i != bytewidth; ++i) { - recon[i] = scanline[i]; - } - for(i = bytewidth; i != length; ++i, ++j) { - /*paethPredictor(recon[i - bytewidth], 0, 0) is always recon[i - bytewidth]*/ - recon[i] = (scanline[i] + recon[j]); - } - } - break; - default: return 36; /*error: invalid 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 + 7u) / 8u; - /*the width of a scanline in bytes, not including the filter type*/ - size_t linebytes = lodepng_get_raw_size_idat(w, 1, bpp) - 1u; - - 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]; - - CERROR_TRY_RETURN(unfilterScanline(&out[outindex], &in[inindex + 1], prevline, bytewidth, filterType, linebytes)); - - prevline = &out[outindex]; - } - - return 0; -} - -/* -in: Adam7 interlaced image, with no padding bits between scanlines, but between - reduced images so that each reduced image starts at a byte. -out: the same pixels, but re-ordered so that they're now a non-interlaced image with size w*h -bpp: bits per pixel -out has the following size in bits: w * h * bpp. -in is possibly bigger due to padding bits between reduced images. -out must be big enough AND must be 0 everywhere if bpp < 8 in the current implementation -(because that's likely a little bit faster) -NOTE: comments about padding bits are only relevant if bpp < 8 -*/ -static void Adam7_deinterlace(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, unsigned bpp) { - 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 / 8u; - 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] + (size_t)y * ADAM7_DY[i]) * (size_t)w - + ADAM7_IX[i] + (size_t)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] + (size_t)y * ADAM7_DY[i]) * olinebits + (ADAM7_IX[i] + (size_t)x * ADAM7_DX[i]) * bpp; - for(b = 0; b < bpp; ++b) { - unsigned char bit = readBitFromReversedStream(&ibp, in); - setBitOfReversedStream(&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, - unsigned w, unsigned h, const LodePNGInfo* info_png) { - /* - This function converts the filtered-padded-interlaced data into pure 2D image buffer with the PNG's colortype. - Steps: - *) if no Adam7: 1) unfilter 2) remove padding bits (= possible 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_get_bpp(&info_png->color); - if(bpp == 0) return 31; /*error: invalid colortype*/ - - if(info_png->interlace_method == 0) { - if(bpp < 8 && w * bpp != ((w * bpp + 7u) / 8u) * 8u) { - CERROR_TRY_RETURN(unfilter(in, in, w, h, bpp)); - removePaddingBits(out, in, w * bpp, ((w * bpp + 7u) / 8u) * 8u, h); - } - /*we can immediately filter into the out buffer, no other steps needed*/ - else CERROR_TRY_RETURN(unfilter(out, in, w, h, bpp)); - } else /*interlace_method 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) { - CERROR_TRY_RETURN(unfilter(&in[padded_passstart[i]], &in[filter_passstart[i]], passw[i], passh[i], bpp)); - /*TODO: possible efficiency improvement: if in this reduced image the bits fit nicely in 1 scanline, - move bytes instead of bits or move not at all*/ - if(bpp < 8) { - /*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 + 7u) / 8u) * 8u, passh[i]); - } - } - - Adam7_deinterlace(out, in, w, h, bpp); - } - - return 0; -} - -static unsigned readChunk_PLTE(LodePNGColorMode* color, const unsigned char* data, size_t chunkLength) { - unsigned pos = 0, i; - color->palettesize = chunkLength / 3u; - if(color->palettesize == 0 || color->palettesize > 256) return 38; /*error: palette too small or big*/ - lodepng_color_mode_alloc_palette(color); - if(!color->palette && color->palettesize) { - color->palettesize = 0; - return 83; /*alloc fail*/ - } - - for(i = 0; i != color->palettesize; ++i) { - color->palette[4 * i + 0] = data[pos++]; /*R*/ - color->palette[4 * i + 1] = data[pos++]; /*G*/ - color->palette[4 * i + 2] = data[pos++]; /*B*/ - color->palette[4 * i + 3] = 255; /*alpha*/ - } - - return 0; /* OK */ -} - -static unsigned readChunk_tRNS(LodePNGColorMode* color, const unsigned char* data, size_t chunkLength) { - unsigned i; - if(color->colortype == LCT_PALETTE) { - /*error: more alpha values given than there are palette entries*/ - if(chunkLength > color->palettesize) return 39; - - for(i = 0; i != chunkLength; ++i) color->palette[4 * i + 3] = data[i]; - } else if(color->colortype == LCT_GREY) { - /*error: this chunk must be 2 bytes for grayscale image*/ - if(chunkLength != 2) return 30; - - color->key_defined = 1; - color->key_r = color->key_g = color->key_b = 256u * data[0] + data[1]; - } else if(color->colortype == LCT_RGB) { - /*error: this chunk must be 6 bytes for RGB image*/ - if(chunkLength != 6) return 41; - - color->key_defined = 1; - color->key_r = 256u * data[0] + data[1]; - color->key_g = 256u * data[2] + data[3]; - color->key_b = 256u * data[4] + data[5]; - } - else return 42; /*error: tRNS chunk not allowed for other color models*/ - - return 0; /* OK */ -} - - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS -/*background color chunk (bKGD)*/ -static unsigned readChunk_bKGD(LodePNGInfo* info, const unsigned char* data, size_t chunkLength) { - if(info->color.colortype == LCT_PALETTE) { - /*error: this chunk must be 1 byte for indexed color image*/ - if(chunkLength != 1) return 43; - - /*error: invalid palette index, or maybe this chunk appeared before PLTE*/ - if(data[0] >= info->color.palettesize) return 103; - - info->background_defined = 1; - info->background_r = info->background_g = info->background_b = data[0]; - } else if(info->color.colortype == LCT_GREY || info->color.colortype == LCT_GREY_ALPHA) { - /*error: this chunk must be 2 bytes for grayscale image*/ - if(chunkLength != 2) return 44; - - /*the values are truncated to bitdepth in the PNG file*/ - info->background_defined = 1; - info->background_r = info->background_g = info->background_b = 256u * data[0] + data[1]; - } else if(info->color.colortype == LCT_RGB || info->color.colortype == LCT_RGBA) { - /*error: this chunk must be 6 bytes for grayscale image*/ - if(chunkLength != 6) return 45; - - /*the values are truncated to bitdepth in the PNG file*/ - info->background_defined = 1; - info->background_r = 256u * data[0] + data[1]; - info->background_g = 256u * data[2] + data[3]; - info->background_b = 256u * data[4] + data[5]; - } - - return 0; /* OK */ -} - -/*text chunk (tEXt)*/ -static unsigned readChunk_tEXt(LodePNGInfo* info, const unsigned char* data, size_t chunkLength) { - unsigned error = 0; - char *key = 0, *str = 0; - - while(!error) /*not really a while loop, only used to break on error*/ { - unsigned length, string2_begin; - - length = 0; - while(length < chunkLength && data[length] != 0) ++length; - /*even though it's not allowed by the standard, no error is thrown if - there's no null termination char, if the text is empty*/ - if(length < 1 || length > 79) CERROR_BREAK(error, 89); /*keyword too short or long*/ - - key = (char*)lodepng_malloc(length + 1); - if(!key) CERROR_BREAK(error, 83); /*alloc fail*/ - - lodepng_memcpy(key, data, length); - key[length] = 0; - - string2_begin = length + 1; /*skip keyword null terminator*/ - - length = (unsigned)(chunkLength < string2_begin ? 0 : chunkLength - string2_begin); - str = (char*)lodepng_malloc(length + 1); - if(!str) CERROR_BREAK(error, 83); /*alloc fail*/ - - lodepng_memcpy(str, data + string2_begin, length); - str[length] = 0; - - error = lodepng_add_text(info, key, str); - - break; - } - - lodepng_free(key); - lodepng_free(str); - - return error; -} - -/*compressed text chunk (zTXt)*/ -static unsigned readChunk_zTXt(LodePNGInfo* info, const LodePNGDecoderSettings* decoder, - const unsigned char* data, size_t chunkLength) { - unsigned error = 0; - - /*copy the object to change parameters in it*/ - LodePNGDecompressSettings zlibsettings = decoder->zlibsettings; - - unsigned length, string2_begin; - char *key = 0; - unsigned char* str = 0; - size_t size = 0; - - while(!error) /*not really a while loop, only used to break on error*/ { - for(length = 0; length < chunkLength && data[length] != 0; ++length) ; - if(length + 2 >= chunkLength) CERROR_BREAK(error, 75); /*no null termination, corrupt?*/ - if(length < 1 || length > 79) CERROR_BREAK(error, 89); /*keyword too short or long*/ - - key = (char*)lodepng_malloc(length + 1); - if(!key) CERROR_BREAK(error, 83); /*alloc fail*/ - - lodepng_memcpy(key, data, length); - key[length] = 0; - - if(data[length + 1] != 0) CERROR_BREAK(error, 72); /*the 0 byte indicating compression must be 0*/ - - string2_begin = length + 2; - if(string2_begin > chunkLength) CERROR_BREAK(error, 75); /*no null termination, corrupt?*/ - - length = (unsigned)chunkLength - string2_begin; - zlibsettings.max_output_size = decoder->max_text_size; - /*will fail if zlib error, e.g. if length is too small*/ - error = zlib_decompress(&str, &size, 0, &data[string2_begin], - length, &zlibsettings); - /*error: compressed text larger than decoder->max_text_size*/ - if(error && size > zlibsettings.max_output_size) error = 112; - if(error) break; - error = lodepng_add_text_sized(info, key, (char*)str, size); - break; - } - - lodepng_free(key); - lodepng_free(str); - - return error; -} - -/*international text chunk (iTXt)*/ -static unsigned readChunk_iTXt(LodePNGInfo* info, const LodePNGDecoderSettings* decoder, - const unsigned char* data, size_t chunkLength) { - unsigned error = 0; - unsigned i; - - /*copy the object to change parameters in it*/ - LodePNGDecompressSettings zlibsettings = decoder->zlibsettings; - - unsigned length, begin, compressed; - char *key = 0, *langtag = 0, *transkey = 0; - - while(!error) /*not really a while loop, only used to break on error*/ { - /*Quick check if the chunk length isn't too small. Even without check - it'd still fail with other error checks below if it's too short. This just gives a different error code.*/ - if(chunkLength < 5) CERROR_BREAK(error, 30); /*iTXt chunk too short*/ - - /*read the key*/ - for(length = 0; length < chunkLength && data[length] != 0; ++length) ; - if(length + 3 >= chunkLength) CERROR_BREAK(error, 75); /*no null termination char, corrupt?*/ - if(length < 1 || length > 79) CERROR_BREAK(error, 89); /*keyword too short or long*/ - - key = (char*)lodepng_malloc(length + 1); - if(!key) CERROR_BREAK(error, 83); /*alloc fail*/ - - lodepng_memcpy(key, data, length); - key[length] = 0; - - /*read the compression method*/ - compressed = data[length + 1]; - if(data[length + 2] != 0) CERROR_BREAK(error, 72); /*the 0 byte indicating compression must be 0*/ - - /*even though it's not allowed by the standard, no error is thrown if - there's no null termination char, if the text is empty for the next 3 texts*/ - - /*read the langtag*/ - begin = length + 3; - length = 0; - for(i = begin; i < chunkLength && data[i] != 0; ++i) ++length; - - langtag = (char*)lodepng_malloc(length + 1); - if(!langtag) CERROR_BREAK(error, 83); /*alloc fail*/ - - lodepng_memcpy(langtag, data + begin, length); - langtag[length] = 0; - - /*read the transkey*/ - begin += length + 1; - length = 0; - for(i = begin; i < chunkLength && data[i] != 0; ++i) ++length; - - transkey = (char*)lodepng_malloc(length + 1); - if(!transkey) CERROR_BREAK(error, 83); /*alloc fail*/ - - lodepng_memcpy(transkey, data + begin, length); - transkey[length] = 0; - - /*read the actual text*/ - begin += length + 1; - - length = (unsigned)chunkLength < begin ? 0 : (unsigned)chunkLength - begin; - - if(compressed) { - unsigned char* str = 0; - size_t size = 0; - zlibsettings.max_output_size = decoder->max_text_size; - /*will fail if zlib error, e.g. if length is too small*/ - error = zlib_decompress(&str, &size, 0, &data[begin], - length, &zlibsettings); - /*error: compressed text larger than decoder->max_text_size*/ - if(error && size > zlibsettings.max_output_size) error = 112; - if(!error) error = lodepng_add_itext_sized(info, key, langtag, transkey, (char*)str, size); - lodepng_free(str); - } else { - error = lodepng_add_itext_sized(info, key, langtag, transkey, (char*)(data + begin), length); - } - - break; - } - - lodepng_free(key); - lodepng_free(langtag); - lodepng_free(transkey); - - return error; -} - -static unsigned readChunk_tIME(LodePNGInfo* info, const unsigned char* data, size_t chunkLength) { - if(chunkLength != 7) return 73; /*invalid tIME chunk size*/ - - info->time_defined = 1; - info->time.year = 256u * data[0] + data[1]; - info->time.month = data[2]; - info->time.day = data[3]; - info->time.hour = data[4]; - info->time.minute = data[5]; - info->time.second = data[6]; - - return 0; /* OK */ -} - -static unsigned readChunk_pHYs(LodePNGInfo* info, const unsigned char* data, size_t chunkLength) { - if(chunkLength != 9) return 74; /*invalid pHYs chunk size*/ - - info->phys_defined = 1; - info->phys_x = 16777216u * data[0] + 65536u * data[1] + 256u * data[2] + data[3]; - info->phys_y = 16777216u * data[4] + 65536u * data[5] + 256u * data[6] + data[7]; - info->phys_unit = data[8]; - - return 0; /* OK */ -} - -static unsigned readChunk_gAMA(LodePNGInfo* info, const unsigned char* data, size_t chunkLength) { - if(chunkLength != 4) return 96; /*invalid gAMA chunk size*/ - - info->gama_defined = 1; - info->gama_gamma = 16777216u * data[0] + 65536u * data[1] + 256u * data[2] + data[3]; - - return 0; /* OK */ -} - -static unsigned readChunk_cHRM(LodePNGInfo* info, const unsigned char* data, size_t chunkLength) { - if(chunkLength != 32) return 97; /*invalid cHRM chunk size*/ - - info->chrm_defined = 1; - info->chrm_white_x = 16777216u * data[ 0] + 65536u * data[ 1] + 256u * data[ 2] + data[ 3]; - info->chrm_white_y = 16777216u * data[ 4] + 65536u * data[ 5] + 256u * data[ 6] + data[ 7]; - info->chrm_red_x = 16777216u * data[ 8] + 65536u * data[ 9] + 256u * data[10] + data[11]; - info->chrm_red_y = 16777216u * data[12] + 65536u * data[13] + 256u * data[14] + data[15]; - info->chrm_green_x = 16777216u * data[16] + 65536u * data[17] + 256u * data[18] + data[19]; - info->chrm_green_y = 16777216u * data[20] + 65536u * data[21] + 256u * data[22] + data[23]; - info->chrm_blue_x = 16777216u * data[24] + 65536u * data[25] + 256u * data[26] + data[27]; - info->chrm_blue_y = 16777216u * data[28] + 65536u * data[29] + 256u * data[30] + data[31]; - - return 0; /* OK */ -} - -static unsigned readChunk_sRGB(LodePNGInfo* info, const unsigned char* data, size_t chunkLength) { - if(chunkLength != 1) return 98; /*invalid sRGB chunk size (this one is never ignored)*/ - - info->srgb_defined = 1; - info->srgb_intent = data[0]; - - return 0; /* OK */ -} - -static unsigned readChunk_iCCP(LodePNGInfo* info, const LodePNGDecoderSettings* decoder, - const unsigned char* data, size_t chunkLength) { - unsigned error = 0; - unsigned i; - size_t size = 0; - /*copy the object to change parameters in it*/ - LodePNGDecompressSettings zlibsettings = decoder->zlibsettings; - - unsigned length, string2_begin; - - info->iccp_defined = 1; - if(info->iccp_name) lodepng_clear_icc(info); - - for(length = 0; length < chunkLength && data[length] != 0; ++length) ; - if(length + 2 >= chunkLength) return 75; /*no null termination, corrupt?*/ - if(length < 1 || length > 79) return 89; /*keyword too short or long*/ - - info->iccp_name = (char*)lodepng_malloc(length + 1); - if(!info->iccp_name) return 83; /*alloc fail*/ - - info->iccp_name[length] = 0; - for(i = 0; i != length; ++i) info->iccp_name[i] = (char)data[i]; - - if(data[length + 1] != 0) return 72; /*the 0 byte indicating compression must be 0*/ - - string2_begin = length + 2; - if(string2_begin > chunkLength) return 75; /*no null termination, corrupt?*/ - - length = (unsigned)chunkLength - string2_begin; - zlibsettings.max_output_size = decoder->max_icc_size; - error = zlib_decompress(&info->iccp_profile, &size, 0, - &data[string2_begin], - length, &zlibsettings); - /*error: ICC profile larger than decoder->max_icc_size*/ - if(error && size > zlibsettings.max_output_size) error = 113; - info->iccp_profile_size = size; - if(!error && !info->iccp_profile_size) error = 100; /*invalid ICC profile size*/ - return error; -} - -/*significant bits chunk (sBIT)*/ -static unsigned readChunk_sBIT(LodePNGInfo* info, const unsigned char* data, size_t chunkLength) { - unsigned bitdepth = (info->color.colortype == LCT_PALETTE) ? 8 : info->color.bitdepth; - if(info->color.colortype == LCT_GREY) { - /*error: this chunk must be 1 bytes for grayscale image*/ - if(chunkLength != 1) return 114; - if(data[0] == 0 || data[0] > bitdepth) return 115; - info->sbit_defined = 1; - info->sbit_r = info->sbit_g = info->sbit_b = data[0]; /*setting g and b is not required, but sensible*/ - } else if(info->color.colortype == LCT_RGB || info->color.colortype == LCT_PALETTE) { - /*error: this chunk must be 3 bytes for RGB and palette image*/ - if(chunkLength != 3) return 114; - if(data[0] == 0 || data[1] == 0 || data[2] == 0) return 115; - if(data[0] > bitdepth || data[1] > bitdepth || data[2] > bitdepth) return 115; - info->sbit_defined = 1; - info->sbit_r = data[0]; - info->sbit_g = data[1]; - info->sbit_b = data[2]; - } else if(info->color.colortype == LCT_GREY_ALPHA) { - /*error: this chunk must be 2 byte for grayscale with alpha image*/ - if(chunkLength != 2) return 114; - if(data[0] == 0 || data[1] == 0) return 115; - if(data[0] > bitdepth || data[1] > bitdepth) return 115; - info->sbit_defined = 1; - info->sbit_r = info->sbit_g = info->sbit_b = data[0]; /*setting g and b is not required, but sensible*/ - info->sbit_a = data[1]; - } else if(info->color.colortype == LCT_RGBA) { - /*error: this chunk must be 4 bytes for grayscale image*/ - if(chunkLength != 4) return 114; - if(data[0] == 0 || data[1] == 0 || data[2] == 0 || data[3] == 0) return 115; - if(data[0] > bitdepth || data[1] > bitdepth || data[2] > bitdepth || data[3] > bitdepth) return 115; - info->sbit_defined = 1; - info->sbit_r = data[0]; - info->sbit_g = data[1]; - info->sbit_b = data[2]; - info->sbit_a = data[3]; - } - - return 0; /* OK */ -} -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - -unsigned lodepng_inspect_chunk(LodePNGState* state, size_t pos, - const unsigned char* in, size_t insize) { - const unsigned char* chunk = in + pos; - unsigned chunkLength; - const unsigned char* data; - unsigned unhandled = 0; - unsigned error = 0; - - if(pos + 4 > insize) return 30; - chunkLength = lodepng_chunk_length(chunk); - if(chunkLength > 2147483647) return 63; - data = lodepng_chunk_data_const(chunk); - if(chunkLength + 12 > insize - pos) return 30; - - if(lodepng_chunk_type_equals(chunk, "PLTE")) { - error = readChunk_PLTE(&state->info_png.color, data, chunkLength); - } else if(lodepng_chunk_type_equals(chunk, "tRNS")) { - error = readChunk_tRNS(&state->info_png.color, data, chunkLength); -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - } else if(lodepng_chunk_type_equals(chunk, "bKGD")) { - error = readChunk_bKGD(&state->info_png, data, chunkLength); - } else if(lodepng_chunk_type_equals(chunk, "tEXt")) { - error = readChunk_tEXt(&state->info_png, data, chunkLength); - } else if(lodepng_chunk_type_equals(chunk, "zTXt")) { - error = readChunk_zTXt(&state->info_png, &state->decoder, data, chunkLength); - } else if(lodepng_chunk_type_equals(chunk, "iTXt")) { - error = readChunk_iTXt(&state->info_png, &state->decoder, data, chunkLength); - } else if(lodepng_chunk_type_equals(chunk, "tIME")) { - error = readChunk_tIME(&state->info_png, data, chunkLength); - } else if(lodepng_chunk_type_equals(chunk, "pHYs")) { - error = readChunk_pHYs(&state->info_png, data, chunkLength); - } else if(lodepng_chunk_type_equals(chunk, "gAMA")) { - error = readChunk_gAMA(&state->info_png, data, chunkLength); - } else if(lodepng_chunk_type_equals(chunk, "cHRM")) { - error = readChunk_cHRM(&state->info_png, data, chunkLength); - } else if(lodepng_chunk_type_equals(chunk, "sRGB")) { - error = readChunk_sRGB(&state->info_png, data, chunkLength); - } else if(lodepng_chunk_type_equals(chunk, "iCCP")) { - error = readChunk_iCCP(&state->info_png, &state->decoder, data, chunkLength); - } else if(lodepng_chunk_type_equals(chunk, "sBIT")) { - error = readChunk_sBIT(&state->info_png, data, chunkLength); -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - } else { - /* unhandled chunk is ok (is not an error) */ - unhandled = 1; - } - - if(!error && !unhandled && !state->decoder.ignore_crc) { - if(lodepng_chunk_check_crc(chunk)) return 57; /*invalid CRC*/ - } - - return error; -} - -/*read a PNG, the result will be in the same color type as the PNG (hence "generic")*/ -static void decodeGeneric(unsigned char** out, unsigned* w, unsigned* h, - LodePNGState* state, - const unsigned char* in, size_t insize) { - unsigned char IEND = 0; - const unsigned char* chunk; /*points to beginning of next chunk*/ - unsigned char* idat; /*the data from idat chunks, zlib compressed*/ - size_t idatsize = 0; - unsigned char* scanlines = 0; - size_t scanlines_size = 0, expected_size = 0; - size_t outsize = 0; - - /*for unknown chunk order*/ - unsigned unknown = 0; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - unsigned critical_pos = 1; /*1 = after IHDR, 2 = after PLTE, 3 = after IDAT*/ -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - - - /* safe output values in case error happens */ - *out = 0; - *w = *h = 0; - - state->error = lodepng_inspect(w, h, state, in, insize); /*reads header and resets other parameters in state->info_png*/ - if(state->error) return; - - if(lodepng_pixel_overflow(*w, *h, &state->info_png.color, &state->info_raw)) { - CERROR_RETURN(state->error, 92); /*overflow possible due to amount of pixels*/ - } - - /*the input filesize is a safe upper bound for the sum of idat chunks size*/ - idat = (unsigned char*)lodepng_malloc(insize); - if(!idat) CERROR_RETURN(state->error, 83); /*alloc fail*/ - - 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 && !state->error) { - unsigned chunkLength; - const unsigned char* data; /*the data in the chunk*/ - size_t pos = (size_t)(chunk - in); - - /*error: next chunk out of bounds of the in buffer*/ - if(chunk < in || pos + 12 > insize) { - if(state->decoder.ignore_end) break; /*other errors may still happen though*/ - CERROR_BREAK(state->error, 30); - } - - /*length of the data of the chunk, excluding the 12 bytes for length, chunk type and CRC*/ - chunkLength = lodepng_chunk_length(chunk); - /*error: chunk length larger than the max PNG chunk size*/ - if(chunkLength > 2147483647) { - if(state->decoder.ignore_end) break; /*other errors may still happen though*/ - CERROR_BREAK(state->error, 63); - } - - if(pos + (size_t)chunkLength + 12 > insize || pos + (size_t)chunkLength + 12 < pos) { - CERROR_BREAK(state->error, 64); /*error: size of the in buffer too small to contain next chunk (or int overflow)*/ - } - - data = lodepng_chunk_data_const(chunk); - - unknown = 0; - - /*IDAT chunk, containing compressed image data*/ - if(lodepng_chunk_type_equals(chunk, "IDAT")) { - size_t newsize; - if(lodepng_addofl(idatsize, chunkLength, &newsize)) CERROR_BREAK(state->error, 95); - if(newsize > insize) CERROR_BREAK(state->error, 95); - lodepng_memcpy(idat + idatsize, data, chunkLength); - idatsize += chunkLength; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - critical_pos = 3; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - } else if(lodepng_chunk_type_equals(chunk, "IEND")) { - /*IEND chunk*/ - IEND = 1; - } else if(lodepng_chunk_type_equals(chunk, "PLTE")) { - /*palette chunk (PLTE)*/ - state->error = readChunk_PLTE(&state->info_png.color, data, chunkLength); - if(state->error) break; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - critical_pos = 2; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - } else if(lodepng_chunk_type_equals(chunk, "tRNS")) { - /*palette transparency chunk (tRNS). Even though this one is an ancillary chunk , it is still compiled - in without 'LODEPNG_COMPILE_ANCILLARY_CHUNKS' because it contains essential color information that - affects the alpha channel of pixels. */ - state->error = readChunk_tRNS(&state->info_png.color, data, chunkLength); - if(state->error) break; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /*background color chunk (bKGD)*/ - } else if(lodepng_chunk_type_equals(chunk, "bKGD")) { - state->error = readChunk_bKGD(&state->info_png, data, chunkLength); - if(state->error) break; - } else if(lodepng_chunk_type_equals(chunk, "tEXt")) { - /*text chunk (tEXt)*/ - if(state->decoder.read_text_chunks) { - state->error = readChunk_tEXt(&state->info_png, data, chunkLength); - if(state->error) break; - } - } else if(lodepng_chunk_type_equals(chunk, "zTXt")) { - /*compressed text chunk (zTXt)*/ - if(state->decoder.read_text_chunks) { - state->error = readChunk_zTXt(&state->info_png, &state->decoder, data, chunkLength); - if(state->error) break; - } - } else if(lodepng_chunk_type_equals(chunk, "iTXt")) { - /*international text chunk (iTXt)*/ - if(state->decoder.read_text_chunks) { - state->error = readChunk_iTXt(&state->info_png, &state->decoder, data, chunkLength); - if(state->error) break; - } - } else if(lodepng_chunk_type_equals(chunk, "tIME")) { - state->error = readChunk_tIME(&state->info_png, data, chunkLength); - if(state->error) break; - } else if(lodepng_chunk_type_equals(chunk, "pHYs")) { - state->error = readChunk_pHYs(&state->info_png, data, chunkLength); - if(state->error) break; - } else if(lodepng_chunk_type_equals(chunk, "gAMA")) { - state->error = readChunk_gAMA(&state->info_png, data, chunkLength); - if(state->error) break; - } else if(lodepng_chunk_type_equals(chunk, "cHRM")) { - state->error = readChunk_cHRM(&state->info_png, data, chunkLength); - if(state->error) break; - } else if(lodepng_chunk_type_equals(chunk, "sRGB")) { - state->error = readChunk_sRGB(&state->info_png, data, chunkLength); - if(state->error) break; - } else if(lodepng_chunk_type_equals(chunk, "iCCP")) { - state->error = readChunk_iCCP(&state->info_png, &state->decoder, data, chunkLength); - if(state->error) break; - } else if(lodepng_chunk_type_equals(chunk, "sBIT")) { - state->error = readChunk_sBIT(&state->info_png, data, chunkLength); - if(state->error) break; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - } else /*it's not an implemented chunk type, so ignore it: skip over the data*/ { - /*error: unknown critical chunk (5th bit of first byte of chunk type is 0)*/ - if(!state->decoder.ignore_critical && !lodepng_chunk_ancillary(chunk)) { - CERROR_BREAK(state->error, 69); - } - - unknown = 1; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - if(state->decoder.remember_unknown_chunks) { - state->error = lodepng_chunk_append(&state->info_png.unknown_chunks_data[critical_pos - 1], - &state->info_png.unknown_chunks_size[critical_pos - 1], chunk); - if(state->error) break; - } -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - } - - if(!state->decoder.ignore_crc && !unknown) /*check CRC if wanted, only on known chunk types*/ { - if(lodepng_chunk_check_crc(chunk)) CERROR_BREAK(state->error, 57); /*invalid CRC*/ - } - - if(!IEND) chunk = lodepng_chunk_next_const(chunk, in + insize); - } - - if(!state->error && state->info_png.color.colortype == LCT_PALETTE && !state->info_png.color.palette) { - state->error = 106; /* error: PNG file must have PLTE chunk if color type is palette */ - } - - if(!state->error) { - /*predict output size, to allocate exact size for output buffer to avoid more dynamic allocation. - If the decompressed size does not match the prediction, the image must be corrupt.*/ - if(state->info_png.interlace_method == 0) { - size_t bpp = lodepng_get_bpp(&state->info_png.color); - expected_size = lodepng_get_raw_size_idat(*w, *h, bpp); - } else { - size_t bpp = lodepng_get_bpp(&state->info_png.color); - /*Adam-7 interlaced: expected size is the sum of the 7 sub-images sizes*/ - expected_size = 0; - expected_size += lodepng_get_raw_size_idat((*w + 7) >> 3, (*h + 7) >> 3, bpp); - if(*w > 4) expected_size += lodepng_get_raw_size_idat((*w + 3) >> 3, (*h + 7) >> 3, bpp); - expected_size += lodepng_get_raw_size_idat((*w + 3) >> 2, (*h + 3) >> 3, bpp); - if(*w > 2) expected_size += lodepng_get_raw_size_idat((*w + 1) >> 2, (*h + 3) >> 2, bpp); - expected_size += lodepng_get_raw_size_idat((*w + 1) >> 1, (*h + 1) >> 2, bpp); - if(*w > 1) expected_size += lodepng_get_raw_size_idat((*w + 0) >> 1, (*h + 1) >> 1, bpp); - expected_size += lodepng_get_raw_size_idat((*w + 0), (*h + 0) >> 1, bpp); - } - - state->error = zlib_decompress(&scanlines, &scanlines_size, expected_size, idat, idatsize, &state->decoder.zlibsettings); - } - if(!state->error && scanlines_size != expected_size) state->error = 91; /*decompressed size doesn't match prediction*/ - lodepng_free(idat); - - if(!state->error) { - outsize = lodepng_get_raw_size(*w, *h, &state->info_png.color); - *out = (unsigned char*)lodepng_malloc(outsize); - if(!*out) state->error = 83; /*alloc fail*/ - } - if(!state->error) { - lodepng_memset(*out, 0, outsize); - state->error = postProcessScanlines(*out, scanlines, *w, *h, &state->info_png); - } - lodepng_free(scanlines); -} - -unsigned lodepng_decode(unsigned char** out, unsigned* w, unsigned* h, - LodePNGState* state, - const unsigned char* in, size_t insize) { - *out = 0; - decodeGeneric(out, w, h, state, in, insize); - if(state->error) return state->error; - if(!state->decoder.color_convert || lodepng_color_mode_equal(&state->info_raw, &state->info_png.color)) { - /*same color type, no copying or converting of data needed*/ - /*store the info_png color settings on the info_raw so that the info_raw still reflects what colortype - the raw image has to the end user*/ - if(!state->decoder.color_convert) { - state->error = lodepng_color_mode_copy(&state->info_raw, &state->info_png.color); - if(state->error) return state->error; - } - } else { /*color conversion needed*/ - unsigned char* data = *out; - size_t outsize; - - /*TODO: check if this works according to the statement in the documentation: "The converter can convert - from grayscale input color type, to 8-bit grayscale or grayscale with alpha"*/ - if(!(state->info_raw.colortype == LCT_RGB || state->info_raw.colortype == LCT_RGBA) - && !(state->info_raw.bitdepth == 8)) { - return 56; /*unsupported color mode conversion*/ - } - - outsize = lodepng_get_raw_size(*w, *h, &state->info_raw); - *out = (unsigned char*)lodepng_malloc(outsize); - if(!(*out)) { - state->error = 83; /*alloc fail*/ - } - else state->error = lodepng_convert(*out, data, &state->info_raw, - &state->info_png.color, *w, *h); - lodepng_free(data); - } - return state->error; -} - -unsigned lodepng_decode_memory(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, - size_t insize, LodePNGColorType colortype, unsigned bitdepth) { - unsigned error; - LodePNGState state; - lodepng_state_init(&state); - state.info_raw.colortype = colortype; - state.info_raw.bitdepth = bitdepth; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /*disable reading things that this function doesn't output*/ - state.decoder.read_text_chunks = 0; - state.decoder.remember_unknown_chunks = 0; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - error = lodepng_decode(out, w, h, &state, in, insize); - lodepng_state_cleanup(&state); - return error; -} - -unsigned lodepng_decode32(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, size_t insize) { - return lodepng_decode_memory(out, w, h, in, insize, LCT_RGBA, 8); -} - -unsigned lodepng_decode24(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, size_t insize) { - return lodepng_decode_memory(out, w, h, in, insize, LCT_RGB, 8); -} - -#ifdef LODEPNG_COMPILE_DISK -unsigned lodepng_decode_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename, - LodePNGColorType colortype, unsigned bitdepth) { - unsigned char* buffer = 0; - size_t buffersize; - unsigned error; - /* safe output values in case error happens */ - *out = 0; - *w = *h = 0; - error = lodepng_load_file(&buffer, &buffersize, filename); - if(!error) error = lodepng_decode_memory(out, w, h, buffer, buffersize, colortype, bitdepth); - lodepng_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, LCT_RGBA, 8); -} - -unsigned lodepng_decode24_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename) { - return lodepng_decode_file(out, w, h, filename, LCT_RGB, 8); -} -#endif /*LODEPNG_COMPILE_DISK*/ - -void lodepng_decoder_settings_init(LodePNGDecoderSettings* settings) { - settings->color_convert = 1; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - settings->read_text_chunks = 1; - settings->remember_unknown_chunks = 0; - settings->max_text_size = 16777216; - settings->max_icc_size = 16777216; /* 16MB is much more than enough for any reasonable ICC profile */ -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - settings->ignore_crc = 0; - settings->ignore_critical = 0; - settings->ignore_end = 0; - lodepng_decompress_settings_init(&settings->zlibsettings); -} - -#endif /*LODEPNG_COMPILE_DECODER*/ - -#if defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) - -void lodepng_state_init(LodePNGState* state) { -#ifdef LODEPNG_COMPILE_DECODER - lodepng_decoder_settings_init(&state->decoder); -#endif /*LODEPNG_COMPILE_DECODER*/ -#ifdef LODEPNG_COMPILE_ENCODER - lodepng_encoder_settings_init(&state->encoder); -#endif /*LODEPNG_COMPILE_ENCODER*/ - lodepng_color_mode_init(&state->info_raw); - lodepng_info_init(&state->info_png); - state->error = 1; -} - -void lodepng_state_cleanup(LodePNGState* state) { - lodepng_color_mode_cleanup(&state->info_raw); - lodepng_info_cleanup(&state->info_png); -} - -void lodepng_state_copy(LodePNGState* dest, const LodePNGState* source) { - lodepng_state_cleanup(dest); - *dest = *source; - lodepng_color_mode_init(&dest->info_raw); - lodepng_info_init(&dest->info_png); - dest->error = lodepng_color_mode_copy(&dest->info_raw, &source->info_raw); if(dest->error) return; - dest->error = lodepng_info_copy(&dest->info_png, &source->info_png); if(dest->error) return; -} - -#endif /* defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) */ - -#ifdef LODEPNG_COMPILE_ENCODER - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / PNG Encoder / */ -/* ////////////////////////////////////////////////////////////////////////// */ - - -static unsigned writeSignature(ucvector* out) { - size_t pos = out->size; - const unsigned char signature[] = {137, 80, 78, 71, 13, 10, 26, 10}; - /*8 bytes PNG signature, aka the magic bytes*/ - if(!ucvector_resize(out, out->size + 8)) return 83; /*alloc fail*/ - lodepng_memcpy(out->data + pos, signature, 8); - return 0; -} - -static unsigned addChunk_IHDR(ucvector* out, unsigned w, unsigned h, - LodePNGColorType colortype, unsigned bitdepth, unsigned interlace_method) { - unsigned char *chunk, *data; - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 13, "IHDR")); - data = chunk + 8; - - lodepng_set32bitInt(data + 0, w); /*width*/ - lodepng_set32bitInt(data + 4, h); /*height*/ - data[8] = (unsigned char)bitdepth; /*bit depth*/ - data[9] = (unsigned char)colortype; /*color type*/ - data[10] = 0; /*compression method*/ - data[11] = 0; /*filter method*/ - data[12] = interlace_method; /*interlace method*/ - - lodepng_chunk_generate_crc(chunk); - return 0; -} - -/* only adds the chunk if needed (there is a key or palette with alpha) */ -static unsigned addChunk_PLTE(ucvector* out, const LodePNGColorMode* info) { - unsigned char* chunk; - size_t i, j = 8; - - if(info->palettesize == 0 || info->palettesize > 256) { - return 68; /*invalid palette size, it is only allowed to be 1-256*/ - } - - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, info->palettesize * 3, "PLTE")); - - for(i = 0; i != info->palettesize; ++i) { - /*add all channels except alpha channel*/ - chunk[j++] = info->palette[i * 4 + 0]; - chunk[j++] = info->palette[i * 4 + 1]; - chunk[j++] = info->palette[i * 4 + 2]; - } - - lodepng_chunk_generate_crc(chunk); - return 0; -} - -static unsigned addChunk_tRNS(ucvector* out, const LodePNGColorMode* info) { - unsigned char* chunk = 0; - - if(info->colortype == LCT_PALETTE) { - size_t i, amount = info->palettesize; - /*the tail of palette values that all have 255 as alpha, does not have to be encoded*/ - for(i = info->palettesize; i != 0; --i) { - if(info->palette[4 * (i - 1) + 3] != 255) break; - --amount; - } - if(amount) { - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, amount, "tRNS")); - /*add the alpha channel values from the palette*/ - for(i = 0; i != amount; ++i) chunk[8 + i] = info->palette[4 * i + 3]; - } - } else if(info->colortype == LCT_GREY) { - if(info->key_defined) { - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 2, "tRNS")); - chunk[8] = (unsigned char)(info->key_r >> 8); - chunk[9] = (unsigned char)(info->key_r & 255); - } - } else if(info->colortype == LCT_RGB) { - if(info->key_defined) { - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 6, "tRNS")); - chunk[8] = (unsigned char)(info->key_r >> 8); - chunk[9] = (unsigned char)(info->key_r & 255); - chunk[10] = (unsigned char)(info->key_g >> 8); - chunk[11] = (unsigned char)(info->key_g & 255); - chunk[12] = (unsigned char)(info->key_b >> 8); - chunk[13] = (unsigned char)(info->key_b & 255); - } - } - - if(chunk) lodepng_chunk_generate_crc(chunk); - return 0; -} - -static unsigned addChunk_IDAT(ucvector* out, const unsigned char* data, size_t datasize, - LodePNGCompressSettings* zlibsettings) { - unsigned error = 0; - unsigned char* zlib = 0; - size_t zlibsize = 0; - - error = zlib_compress(&zlib, &zlibsize, data, datasize, zlibsettings); - if(!error) { - error = lodepng_chunk_createv(out, zlibsize, "IDAT", zlib); - } - lodepng_free(zlib); - return error; -} - -static unsigned addChunk_IEND(ucvector* out) { - return lodepng_chunk_createv(out, 0, "IEND", 0); -} - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - -static unsigned addChunk_tEXt(ucvector* out, const char* keyword, const char* textstring) { - unsigned char* chunk = 0; - size_t keysize = lodepng_strlen(keyword), textsize = lodepng_strlen(textstring); - size_t size = keysize + 1 + textsize; - if(keysize < 1 || keysize > 79) return 89; /*error: invalid keyword size*/ - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, size, "tEXt")); - lodepng_memcpy(chunk + 8, keyword, keysize); - chunk[8 + keysize] = 0; /*null termination char*/ - lodepng_memcpy(chunk + 9 + keysize, textstring, textsize); - lodepng_chunk_generate_crc(chunk); - return 0; -} - -static unsigned addChunk_zTXt(ucvector* out, const char* keyword, const char* textstring, - LodePNGCompressSettings* zlibsettings) { - unsigned error = 0; - unsigned char* chunk = 0; - unsigned char* compressed = 0; - size_t compressedsize = 0; - size_t textsize = lodepng_strlen(textstring); - size_t keysize = lodepng_strlen(keyword); - if(keysize < 1 || keysize > 79) return 89; /*error: invalid keyword size*/ - - error = zlib_compress(&compressed, &compressedsize, - (const unsigned char*)textstring, textsize, zlibsettings); - if(!error) { - size_t size = keysize + 2 + compressedsize; - error = lodepng_chunk_init(&chunk, out, size, "zTXt"); - } - if(!error) { - lodepng_memcpy(chunk + 8, keyword, keysize); - chunk[8 + keysize] = 0; /*null termination char*/ - chunk[9 + keysize] = 0; /*compression method: 0*/ - lodepng_memcpy(chunk + 10 + keysize, compressed, compressedsize); - lodepng_chunk_generate_crc(chunk); - } - - lodepng_free(compressed); - return error; -} - -static unsigned addChunk_iTXt(ucvector* out, unsigned compress, const char* keyword, const char* langtag, - const char* transkey, const char* textstring, LodePNGCompressSettings* zlibsettings) { - unsigned error = 0; - unsigned char* chunk = 0; - unsigned char* compressed = 0; - size_t compressedsize = 0; - size_t textsize = lodepng_strlen(textstring); - size_t keysize = lodepng_strlen(keyword), langsize = lodepng_strlen(langtag), transsize = lodepng_strlen(transkey); - - if(keysize < 1 || keysize > 79) return 89; /*error: invalid keyword size*/ - - if(compress) { - error = zlib_compress(&compressed, &compressedsize, - (const unsigned char*)textstring, textsize, zlibsettings); - } - if(!error) { - size_t size = keysize + 3 + langsize + 1 + transsize + 1 + (compress ? compressedsize : textsize); - error = lodepng_chunk_init(&chunk, out, size, "iTXt"); - } - if(!error) { - size_t pos = 8; - lodepng_memcpy(chunk + pos, keyword, keysize); - pos += keysize; - chunk[pos++] = 0; /*null termination char*/ - chunk[pos++] = (compress ? 1 : 0); /*compression flag*/ - chunk[pos++] = 0; /*compression method: 0*/ - lodepng_memcpy(chunk + pos, langtag, langsize); - pos += langsize; - chunk[pos++] = 0; /*null termination char*/ - lodepng_memcpy(chunk + pos, transkey, transsize); - pos += transsize; - chunk[pos++] = 0; /*null termination char*/ - if(compress) { - lodepng_memcpy(chunk + pos, compressed, compressedsize); - } else { - lodepng_memcpy(chunk + pos, textstring, textsize); - } - lodepng_chunk_generate_crc(chunk); - } - - lodepng_free(compressed); - return error; -} - -static unsigned addChunk_bKGD(ucvector* out, const LodePNGInfo* info) { - unsigned char* chunk = 0; - if(info->color.colortype == LCT_GREY || info->color.colortype == LCT_GREY_ALPHA) { - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 2, "bKGD")); - chunk[8] = (unsigned char)(info->background_r >> 8); - chunk[9] = (unsigned char)(info->background_r & 255); - } else if(info->color.colortype == LCT_RGB || info->color.colortype == LCT_RGBA) { - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 6, "bKGD")); - chunk[8] = (unsigned char)(info->background_r >> 8); - chunk[9] = (unsigned char)(info->background_r & 255); - chunk[10] = (unsigned char)(info->background_g >> 8); - chunk[11] = (unsigned char)(info->background_g & 255); - chunk[12] = (unsigned char)(info->background_b >> 8); - chunk[13] = (unsigned char)(info->background_b & 255); - } else if(info->color.colortype == LCT_PALETTE) { - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 1, "bKGD")); - chunk[8] = (unsigned char)(info->background_r & 255); /*palette index*/ - } - if(chunk) lodepng_chunk_generate_crc(chunk); - return 0; -} - -static unsigned addChunk_tIME(ucvector* out, const LodePNGTime* time) { - unsigned char* chunk; - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 7, "tIME")); - chunk[8] = (unsigned char)(time->year >> 8); - chunk[9] = (unsigned char)(time->year & 255); - chunk[10] = (unsigned char)time->month; - chunk[11] = (unsigned char)time->day; - chunk[12] = (unsigned char)time->hour; - chunk[13] = (unsigned char)time->minute; - chunk[14] = (unsigned char)time->second; - lodepng_chunk_generate_crc(chunk); - return 0; -} - -static unsigned addChunk_pHYs(ucvector* out, const LodePNGInfo* info) { - unsigned char* chunk; - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 9, "pHYs")); - lodepng_set32bitInt(chunk + 8, info->phys_x); - lodepng_set32bitInt(chunk + 12, info->phys_y); - chunk[16] = info->phys_unit; - lodepng_chunk_generate_crc(chunk); - return 0; -} - -static unsigned addChunk_gAMA(ucvector* out, const LodePNGInfo* info) { - unsigned char* chunk; - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 4, "gAMA")); - lodepng_set32bitInt(chunk + 8, info->gama_gamma); - lodepng_chunk_generate_crc(chunk); - return 0; -} - -static unsigned addChunk_cHRM(ucvector* out, const LodePNGInfo* info) { - unsigned char* chunk; - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 32, "cHRM")); - lodepng_set32bitInt(chunk + 8, info->chrm_white_x); - lodepng_set32bitInt(chunk + 12, info->chrm_white_y); - lodepng_set32bitInt(chunk + 16, info->chrm_red_x); - lodepng_set32bitInt(chunk + 20, info->chrm_red_y); - lodepng_set32bitInt(chunk + 24, info->chrm_green_x); - lodepng_set32bitInt(chunk + 28, info->chrm_green_y); - lodepng_set32bitInt(chunk + 32, info->chrm_blue_x); - lodepng_set32bitInt(chunk + 36, info->chrm_blue_y); - lodepng_chunk_generate_crc(chunk); - return 0; -} - -static unsigned addChunk_sRGB(ucvector* out, const LodePNGInfo* info) { - unsigned char data = info->srgb_intent; - return lodepng_chunk_createv(out, 1, "sRGB", &data); -} - -static unsigned addChunk_iCCP(ucvector* out, const LodePNGInfo* info, LodePNGCompressSettings* zlibsettings) { - unsigned error = 0; - unsigned char* chunk = 0; - unsigned char* compressed = 0; - size_t compressedsize = 0; - size_t keysize = lodepng_strlen(info->iccp_name); - - if(keysize < 1 || keysize > 79) return 89; /*error: invalid keyword size*/ - error = zlib_compress(&compressed, &compressedsize, - info->iccp_profile, info->iccp_profile_size, zlibsettings); - if(!error) { - size_t size = keysize + 2 + compressedsize; - error = lodepng_chunk_init(&chunk, out, size, "iCCP"); - } - if(!error) { - lodepng_memcpy(chunk + 8, info->iccp_name, keysize); - chunk[8 + keysize] = 0; /*null termination char*/ - chunk[9 + keysize] = 0; /*compression method: 0*/ - lodepng_memcpy(chunk + 10 + keysize, compressed, compressedsize); - lodepng_chunk_generate_crc(chunk); - } - - lodepng_free(compressed); - return error; -} - -static unsigned addChunk_sBIT(ucvector* out, const LodePNGInfo* info) { - unsigned bitdepth = (info->color.colortype == LCT_PALETTE) ? 8 : info->color.bitdepth; - unsigned char* chunk = 0; - if(info->color.colortype == LCT_GREY) { - if(info->sbit_r == 0 || info->sbit_r > bitdepth) return 115; - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 1, "sBIT")); - chunk[8] = info->sbit_r; - } else if(info->color.colortype == LCT_RGB || info->color.colortype == LCT_PALETTE) { - if(info->sbit_r == 0 || info->sbit_g == 0 || info->sbit_b == 0) return 115; - if(info->sbit_r > bitdepth || info->sbit_g > bitdepth || info->sbit_b > bitdepth) return 115; - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 3, "sBIT")); - chunk[8] = info->sbit_r; - chunk[9] = info->sbit_g; - chunk[10] = info->sbit_b; - } else if(info->color.colortype == LCT_GREY_ALPHA) { - if(info->sbit_r == 0 || info->sbit_a == 0) return 115; - if(info->sbit_r > bitdepth || info->sbit_a > bitdepth) return 115; - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 2, "sBIT")); - chunk[8] = info->sbit_r; - chunk[9] = info->sbit_a; - } else if(info->color.colortype == LCT_RGBA) { - if(info->sbit_r == 0 || info->sbit_g == 0 || info->sbit_b == 0 || info->sbit_a == 0 || - info->sbit_r > bitdepth || info->sbit_g > bitdepth || - info->sbit_b > bitdepth || info->sbit_a > bitdepth) { - return 115; - } - CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 4, "sBIT")); - chunk[8] = info->sbit_r; - chunk[9] = info->sbit_g; - chunk[10] = info->sbit_b; - chunk[11] = info->sbit_a; - } - if(chunk) lodepng_chunk_generate_crc(chunk); - return 0; -} - -#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*/ - 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] >> 1); - for(i = bytewidth; i < length; ++i) out[i] = scanline[i] - ((scanline[i - bytewidth] + prevline[i]) >> 1); - } else { - for(i = 0; i != bytewidth; ++i) out[i] = scanline[i]; - for(i = bytewidth; i < length; ++i) out[i] = scanline[i] - (scanline[i - bytewidth] >> 1); - } - 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; /*invalid filter type given*/ - } -} - -/* integer binary logarithm, max return value is 31 */ -static size_t ilog2(size_t i) { - size_t result = 0; - if(i >= 65536) { result += 16; i >>= 16; } - if(i >= 256) { result += 8; i >>= 8; } - if(i >= 16) { result += 4; i >>= 4; } - if(i >= 4) { result += 2; i >>= 2; } - if(i >= 2) { result += 1; /*i >>= 1;*/ } - return result; -} - -/* integer approximation for i * log2(i), helper function for LFS_ENTROPY */ -static size_t ilog2i(size_t i) { - size_t l; - if(i == 0) return 0; - l = ilog2(i); - /* approximate i*log2(i): l is integer logarithm, ((i - (1u << l)) << 1u) - linearly approximates the missing fractional part multiplied by i */ - return i * l + ((i - (1u << l)) << 1u); -} - -static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, - const LodePNGColorMode* color, const LodePNGEncoderSettings* settings) { - /* - For PNG filter method 0 - out must be a buffer with as size: h + (w * h * bpp + 7u) / 8u, because there are - the scanlines with 1 extra byte per scanline - */ - - unsigned bpp = lodepng_get_bpp(color); - /*the width of a scanline in bytes, not including the filter type*/ - size_t linebytes = lodepng_get_raw_size_idat(w, 1, bpp) - 1u; - - /*bytewidth is used for filtering, is 1 when bpp < 8, number of bytes per pixel otherwise*/ - size_t bytewidth = (bpp + 7u) / 8u; - const unsigned char* prevline = 0; - unsigned x, y; - unsigned error = 0; - LodePNGFilterStrategy strategy = settings->filter_strategy; - - /* - There is a heuristic called the minimum sum of absolute differences heuristic, suggested by the PNG standard: - * If the image type is Palette, or the bit depth is smaller than 8, then do not filter the image (i.e. - use fixed filtering, with the filter None). - * (The other case) If the image type is Grayscale or RGB (with or without Alpha), and the bit depth is - not smaller than 8, then use adaptive filtering heuristic as follows: independently for each row, apply - all five filters and select the filter that produces the smallest sum of absolute values per row. - This heuristic is used if filter strategy is LFS_MINSUM and filter_palette_zero is true. - - If filter_palette_zero is true and filter_strategy is not LFS_MINSUM, the above heuristic is followed, - but for "the other case", whatever strategy filter_strategy is set to instead of the minimum sum - heuristic is used. - */ - if(settings->filter_palette_zero && - (color->colortype == LCT_PALETTE || color->bitdepth < 8)) strategy = LFS_ZERO; - - if(bpp == 0) return 31; /*error: invalid color type*/ - - if(strategy >= LFS_ZERO && strategy <= LFS_FOUR) { - unsigned char type = (unsigned char)strategy; - for(y = 0; y != h; ++y) { - size_t outindex = (1 + linebytes) * y; /*the extra filterbyte added to each row*/ - size_t inindex = linebytes * y; - out[outindex] = type; /*filter type byte*/ - filterScanline(&out[outindex + 1], &in[inindex], prevline, linebytes, bytewidth, type); - prevline = &in[inindex]; - } - } else if(strategy == LFS_MINSUM) { - /*adaptive filtering*/ - unsigned char* attempt[5]; /*five filtering attempts, one for each filter type*/ - size_t smallest = 0; - unsigned char type, bestType = 0; - - for(type = 0; type != 5; ++type) { - attempt[type] = (unsigned char*)lodepng_malloc(linebytes); - if(!attempt[type]) error = 83; /*alloc fail*/ - } - - if(!error) { - for(y = 0; y != h; ++y) { - /*try the 5 filter types*/ - for(type = 0; type != 5; ++type) { - size_t sum = 0; - filterScanline(attempt[type], &in[y * linebytes], prevline, linebytes, bytewidth, type); - - /*calculate the sum of the result*/ - if(type == 0) { - for(x = 0; x != linebytes; ++x) sum += (unsigned char)(attempt[type][x]); - } else { - for(x = 0; x != linebytes; ++x) { - /*For differences, each byte should be treated as signed, values above 127 are negative - (converted to signed char). Filtertype 0 isn't a difference though, so use unsigned there. - This means filtertype 0 is almost never chosen, but that is justified.*/ - unsigned char s = attempt[type][x]; - sum += s < 128 ? s : (255U - 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 < smallest) { - bestType = type; - smallest = sum; - } - } - - 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][x]; - } - } - - for(type = 0; type != 5; ++type) lodepng_free(attempt[type]); - } else if(strategy == LFS_ENTROPY) { - unsigned char* attempt[5]; /*five filtering attempts, one for each filter type*/ - size_t bestSum = 0; - unsigned type, bestType = 0; - unsigned count[256]; - - for(type = 0; type != 5; ++type) { - attempt[type] = (unsigned char*)lodepng_malloc(linebytes); - if(!attempt[type]) error = 83; /*alloc fail*/ - } - - if(!error) { - for(y = 0; y != h; ++y) { - /*try the 5 filter types*/ - for(type = 0; type != 5; ++type) { - size_t sum = 0; - filterScanline(attempt[type], &in[y * linebytes], prevline, linebytes, bytewidth, type); - lodepng_memset(count, 0, 256 * sizeof(*count)); - for(x = 0; x != linebytes; ++x) ++count[attempt[type][x]]; - ++count[type]; /*the filter type itself is part of the scanline*/ - for(x = 0; x != 256; ++x) { - sum += ilog2i(count[x]); - } - /*check if this is smallest sum (or if type == 0 it's the first case so always store the values)*/ - if(type == 0 || sum > bestSum) { - bestType = type; - bestSum = sum; - } - } - - 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][x]; - } - } - - for(type = 0; type != 5; ++type) lodepng_free(attempt[type]); - } else if(strategy == LFS_PREDEFINED) { - for(y = 0; y != h; ++y) { - size_t outindex = (1 + linebytes) * y; /*the extra filterbyte added to each row*/ - size_t inindex = linebytes * y; - unsigned char type = settings->predefined_filters[y]; - out[outindex] = type; /*filter type byte*/ - filterScanline(&out[outindex + 1], &in[inindex], prevline, linebytes, bytewidth, type); - prevline = &in[inindex]; - } - } else if(strategy == LFS_BRUTE_FORCE) { - /*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]; - unsigned char* attempt[5]; /*five filtering attempts, one for each filter type*/ - size_t smallest = 0; - unsigned type = 0, bestType = 0; - unsigned char* dummy; - LodePNGCompressSettings zlibsettings; - lodepng_memcpy(&zlibsettings, &settings->zlibsettings, sizeof(LodePNGCompressSettings)); - /*use fixed tree on the attempts so that the tree is not adapted to the filtertype on purpose, - to simulate the true case where the tree is the same for the whole image. Sometimes it gives - better result with dynamic tree anyway. Using the fixed tree sometimes gives worse, but in rare - cases better compression. It does make this a bit less slow, so it's worth doing this.*/ - zlibsettings.btype = 1; - /*a custom encoder likely doesn't read the btype setting and is optimized for complete PNG - images only, so disable it*/ - zlibsettings.custom_zlib = 0; - zlibsettings.custom_deflate = 0; - for(type = 0; type != 5; ++type) { - attempt[type] = (unsigned char*)lodepng_malloc(linebytes); - if(!attempt[type]) error = 83; /*alloc fail*/ - } - if(!error) { - for(y = 0; y != h; ++y) /*try the 5 filter types*/ { - for(type = 0; type != 5; ++type) { - unsigned testsize = (unsigned)linebytes; - /*if(testsize > 8) testsize /= 8;*/ /*it already works good enough by testing a part of the row*/ - - filterScanline(attempt[type], &in[y * linebytes], prevline, linebytes, bytewidth, type); - size[type] = 0; - dummy = 0; - zlib_compress(&dummy, &size[type], attempt[type], testsize, &zlibsettings); - lodepng_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][x]; - } - } - for(type = 0; type != 5; ++type) lodepng_free(attempt[type]); - } - else return 88; /* unknown filter strategy */ - - 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); - } -} - -/* -in: non-interlaced image with size w*h -out: the same pixels, but re-ordered according to PNG's Adam7 interlacing, with - no padding bits between scanlines, but between reduced images so that each - reduced image starts at a byte. -bpp: bits per pixel -there are no padding bits, not between scanlines, not between reduced images -in has the following size in bits: w * h * bpp. -out is possibly bigger due to padding bits between reduced images -NOTE: comments about padding bits are only relevant if bpp < 8 -*/ -static void Adam7_interlace(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, unsigned bpp) { - 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 / 8u; - 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, - unsigned w, unsigned h, - const LodePNGInfo* info_png, const LodePNGEncoderSettings* settings) { - /* - This function converts the pure 2D image with the PNG's colortype, into filtered-padded-interlaced data. Steps: - *) if no Adam7: 1) add padding bits (= possible 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_get_bpp(&info_png->color); - unsigned error = 0; - - if(info_png->interlace_method == 0) { - *outsize = h + (h * ((w * bpp + 7u) / 8u)); /*image size plus an extra byte per scanline + possible padding bits*/ - *out = (unsigned char*)lodepng_malloc(*outsize); - if(!(*out) && (*outsize)) error = 83; /*alloc fail*/ - - if(!error) { - /*non multiple of 8 bits per scanline, padding bits needed per scanline*/ - if(bpp < 8 && w * bpp != ((w * bpp + 7u) / 8u) * 8u) { - unsigned char* padded = (unsigned char*)lodepng_malloc(h * ((w * bpp + 7u) / 8u)); - if(!padded) error = 83; /*alloc fail*/ - if(!error) { - addPaddingBits(padded, in, ((w * bpp + 7u) / 8u) * 8u, w * bpp, h); - error = filter(*out, padded, w, h, &info_png->color, settings); - } - lodepng_free(padded); - } else { - /*we can immediately filter into the out buffer, no other steps needed*/ - error = filter(*out, in, w, h, &info_png->color, settings); - } - } - } else /*interlace_method is 1 (Adam7)*/ { - unsigned passw[7], passh[7]; - size_t filter_passstart[8], padded_passstart[8], passstart[8]; - unsigned char* adam7; - - 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*)lodepng_malloc(*outsize); - if(!(*out)) error = 83; /*alloc fail*/ - - adam7 = (unsigned char*)lodepng_malloc(passstart[7]); - if(!adam7 && passstart[7]) error = 83; /*alloc fail*/ - - if(!error) { - unsigned i; - - Adam7_interlace(adam7, in, w, h, bpp); - for(i = 0; i != 7; ++i) { - if(bpp < 8) { - unsigned char* padded = (unsigned char*)lodepng_malloc(padded_passstart[i + 1] - padded_passstart[i]); - if(!padded) ERROR_BREAK(83); /*alloc fail*/ - addPaddingBits(padded, &adam7[passstart[i]], - ((passw[i] * bpp + 7u) / 8u) * 8u, passw[i] * bpp, passh[i]); - error = filter(&(*out)[filter_passstart[i]], padded, - passw[i], passh[i], &info_png->color, settings); - lodepng_free(padded); - } else { - error = filter(&(*out)[filter_passstart[i]], &adam7[padded_passstart[i]], - passw[i], passh[i], &info_png->color, settings); - } - - if(error) break; - } - } - - lodepng_free(adam7); - } - - return error; -} - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS -static unsigned addUnknownChunks(ucvector* out, unsigned char* data, size_t datasize) { - unsigned char* inchunk = data; - while((size_t)(inchunk - data) < datasize) { - CERROR_TRY_RETURN(lodepng_chunk_append(&out->data, &out->size, inchunk)); - out->allocsize = out->size; /*fix the allocsize again*/ - inchunk = lodepng_chunk_next(inchunk, data + datasize); - } - return 0; -} - -static unsigned isGrayICCProfile(const unsigned char* profile, unsigned size) { - /* - It is a gray profile if bytes 16-19 are "GRAY", rgb profile if bytes 16-19 - are "RGB ". We do not perform any full parsing of the ICC profile here, other - than check those 4 bytes to grayscale profile. Other than that, validity of - the profile is not checked. This is needed only because the PNG specification - requires using a non-gray color model if there is an ICC profile with "RGB " - (sadly limiting compression opportunities if the input data is grayscale RGB - data), and requires using a gray color model if it is "GRAY". - */ - if(size < 20) return 0; - return profile[16] == 'G' && profile[17] == 'R' && profile[18] == 'A' && profile[19] == 'Y'; -} - -static unsigned isRGBICCProfile(const unsigned char* profile, unsigned size) { - /* See comment in isGrayICCProfile*/ - if(size < 20) return 0; - return profile[16] == 'R' && profile[17] == 'G' && profile[18] == 'B' && profile[19] == ' '; -} -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - -unsigned lodepng_encode(unsigned char** out, size_t* outsize, - const unsigned char* image, unsigned w, unsigned h, - LodePNGState* state) { - unsigned char* data = 0; /*uncompressed version of the IDAT chunk data*/ - size_t datasize = 0; - ucvector outv = ucvector_init(NULL, 0); - LodePNGInfo info; - const LodePNGInfo* info_png = &state->info_png; - LodePNGColorMode auto_color; - - lodepng_info_init(&info); - lodepng_color_mode_init(&auto_color); - - /*provide some proper output values if error will happen*/ - *out = 0; - *outsize = 0; - state->error = 0; - - /*check input values validity*/ - if((info_png->color.colortype == LCT_PALETTE || state->encoder.force_palette) - && (info_png->color.palettesize == 0 || info_png->color.palettesize > 256)) { - /*this error is returned even if auto_convert is enabled and thus encoder could - generate the palette by itself: while allowing this could be possible in theory, - it may complicate the code or edge cases, and always requiring to give a palette - when setting this color type is a simpler contract*/ - state->error = 68; /*invalid palette size, it is only allowed to be 1-256*/ - goto cleanup; - } - if(state->encoder.zlibsettings.btype > 2) { - state->error = 61; /*error: invalid btype*/ - goto cleanup; - } - if(info_png->interlace_method > 1) { - state->error = 71; /*error: invalid interlace mode*/ - goto cleanup; - } - state->error = checkColorValidity(info_png->color.colortype, info_png->color.bitdepth); - if(state->error) goto cleanup; /*error: invalid color type given*/ - state->error = checkColorValidity(state->info_raw.colortype, state->info_raw.bitdepth); - if(state->error) goto cleanup; /*error: invalid color type given*/ - - /* color convert and compute scanline filter types */ - lodepng_info_copy(&info, &state->info_png); - if(state->encoder.auto_convert) { - LodePNGColorStats stats; - unsigned allow_convert = 1; - lodepng_color_stats_init(&stats); -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - if(info_png->iccp_defined && - isGrayICCProfile(info_png->iccp_profile, info_png->iccp_profile_size)) { - /*the PNG specification does not allow to use palette with a GRAY ICC profile, even - if the palette has only gray colors, so disallow it.*/ - stats.allow_palette = 0; - } - if(info_png->iccp_defined && - isRGBICCProfile(info_png->iccp_profile, info_png->iccp_profile_size)) { - /*the PNG specification does not allow to use grayscale color with RGB ICC profile, so disallow gray.*/ - stats.allow_greyscale = 0; - } -#endif /* LODEPNG_COMPILE_ANCILLARY_CHUNKS */ - state->error = lodepng_compute_color_stats(&stats, image, w, h, &state->info_raw); - if(state->error) goto cleanup; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - if(info_png->background_defined) { - /*the background chunk's color must be taken into account as well*/ - unsigned r = 0, g = 0, b = 0; - LodePNGColorMode mode16 = lodepng_color_mode_make(LCT_RGB, 16); - lodepng_convert_rgb(&r, &g, &b, - info_png->background_r, info_png->background_g, info_png->background_b, &mode16, &info_png->color); - state->error = lodepng_color_stats_add(&stats, r, g, b, 65535); - if(state->error) goto cleanup; - } -#endif /* LODEPNG_COMPILE_ANCILLARY_CHUNKS */ - state->error = auto_choose_color(&auto_color, &state->info_raw, &stats); - if(state->error) goto cleanup; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - if(info_png->sbit_defined) { - /*if sbit is defined, due to strict requirements of which sbit values can be present for which color modes, - auto_convert can't be done in many cases. However, do support a few cases here. - TODO: more conversions may be possible, and it may also be possible to get a more appropriate color type out of - auto_choose_color if knowledge about sbit is used beforehand - */ - unsigned sbit_max = LODEPNG_MAX(LODEPNG_MAX(LODEPNG_MAX(info_png->sbit_r, info_png->sbit_g), - info_png->sbit_b), info_png->sbit_a); - unsigned equal = (!info_png->sbit_g || info_png->sbit_g == info_png->sbit_r) - && (!info_png->sbit_b || info_png->sbit_b == info_png->sbit_r) - && (!info_png->sbit_a || info_png->sbit_a == info_png->sbit_r); - allow_convert = 0; - if(info.color.colortype == LCT_PALETTE && - auto_color.colortype == LCT_PALETTE) { - /* input and output are palette, and in this case it may happen that palette data is - expected to be copied from info_raw into the info_png */ - allow_convert = 1; - } - /*going from 8-bit RGB to palette (or 16-bit as long as sbit_max <= 8) is possible - since both are 8-bit RGB for sBIT's purposes*/ - if(info.color.colortype == LCT_RGB && - auto_color.colortype == LCT_PALETTE && sbit_max <= 8) { - allow_convert = 1; - } - /*going from 8-bit RGBA to palette is also ok but only if sbit_a is exactly 8*/ - if(info.color.colortype == LCT_RGBA && auto_color.colortype == LCT_PALETTE && - info_png->sbit_a == 8 && sbit_max <= 8) { - allow_convert = 1; - } - /*going from 16-bit RGB(A) to 8-bit RGB(A) is ok if all sbit values are <= 8*/ - if((info.color.colortype == LCT_RGB || info.color.colortype == LCT_RGBA) && info.color.bitdepth == 16 && - auto_color.colortype == info.color.colortype && auto_color.bitdepth == 8 && - sbit_max <= 8) { - allow_convert = 1; - } - /*going to less channels is ok if all bit values are equal (all possible values in sbit, - as well as the chosen bitdepth of the result). Due to how auto_convert works, - we already know that auto_color.colortype has less than or equal amount of channels than - info.colortype. Palette is not used here. This conversion is not allowed if - info_png->sbit_r < auto_color.bitdepth, because specifically for alpha, non-presence of - an sbit value heavily implies that alpha's bit depth is equal to the PNG bit depth (rather - than the bit depths set in the r, g and b sbit values, by how the PNG specification describes - handling tRNS chunk case with sBIT), so be conservative here about ignoring user input.*/ - if(info.color.colortype != LCT_PALETTE && auto_color.colortype != LCT_PALETTE && - equal && info_png->sbit_r == auto_color.bitdepth) { - allow_convert = 1; - } - } -#endif - if(state->encoder.force_palette) { - if(info.color.colortype != LCT_GREY && info.color.colortype != LCT_GREY_ALPHA && - (auto_color.colortype == LCT_GREY || auto_color.colortype == LCT_GREY_ALPHA)) { - /*user speficially forced a PLTE palette, so cannot convert to grayscale types because - the PNG specification only allows writing a suggested palette in PLTE for truecolor types*/ - allow_convert = 0; - } - } - if(allow_convert) { - lodepng_color_mode_copy(&info.color, &auto_color); -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /*also convert the background chunk*/ - if(info_png->background_defined) { - if(lodepng_convert_rgb(&info.background_r, &info.background_g, &info.background_b, - info_png->background_r, info_png->background_g, info_png->background_b, &info.color, &info_png->color)) { - state->error = 104; - goto cleanup; - } - } -#endif /* LODEPNG_COMPILE_ANCILLARY_CHUNKS */ - } - } -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - if(info_png->iccp_defined) { - unsigned gray_icc = isGrayICCProfile(info_png->iccp_profile, info_png->iccp_profile_size); - unsigned rgb_icc = isRGBICCProfile(info_png->iccp_profile, info_png->iccp_profile_size); - unsigned gray_png = info.color.colortype == LCT_GREY || info.color.colortype == LCT_GREY_ALPHA; - if(!gray_icc && !rgb_icc) { - state->error = 100; /* Disallowed profile color type for PNG */ - goto cleanup; - } - if(gray_icc != gray_png) { - /*Not allowed to use RGB/RGBA/palette with GRAY ICC profile or vice versa, - or in case of auto_convert, it wasn't possible to find appropriate model*/ - state->error = state->encoder.auto_convert ? 102 : 101; - goto cleanup; - } - } -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - if(!lodepng_color_mode_equal(&state->info_raw, &info.color)) { - unsigned char* converted; - size_t size = ((size_t)w * (size_t)h * (size_t)lodepng_get_bpp(&info.color) + 7u) / 8u; - - converted = (unsigned char*)lodepng_malloc(size); - if(!converted && size) state->error = 83; /*alloc fail*/ - if(!state->error) { - state->error = lodepng_convert(converted, image, &info.color, &state->info_raw, w, h); - } - if(!state->error) { - state->error = preProcessScanlines(&data, &datasize, converted, w, h, &info, &state->encoder); - } - lodepng_free(converted); - if(state->error) goto cleanup; - } else { - state->error = preProcessScanlines(&data, &datasize, image, w, h, &info, &state->encoder); - if(state->error) goto cleanup; - } - - /* output all PNG chunks */ { -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - size_t i; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - /*write signature and chunks*/ - state->error = writeSignature(&outv); - if(state->error) goto cleanup; - /*IHDR*/ - state->error = addChunk_IHDR(&outv, w, h, info.color.colortype, info.color.bitdepth, info.interlace_method); - if(state->error) goto cleanup; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /*unknown chunks between IHDR and PLTE*/ - if(info.unknown_chunks_data[0]) { - state->error = addUnknownChunks(&outv, info.unknown_chunks_data[0], info.unknown_chunks_size[0]); - if(state->error) goto cleanup; - } - /*color profile chunks must come before PLTE */ - if(info.iccp_defined) { - state->error = addChunk_iCCP(&outv, &info, &state->encoder.zlibsettings); - if(state->error) goto cleanup; - } - if(info.srgb_defined) { - state->error = addChunk_sRGB(&outv, &info); - if(state->error) goto cleanup; - } - if(info.gama_defined) { - state->error = addChunk_gAMA(&outv, &info); - if(state->error) goto cleanup; - } - if(info.chrm_defined) { - state->error = addChunk_cHRM(&outv, &info); - if(state->error) goto cleanup; - } - if(info_png->sbit_defined) { - state->error = addChunk_sBIT(&outv, &info); - if(state->error) goto cleanup; - } -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - /*PLTE*/ - if(info.color.colortype == LCT_PALETTE) { - state->error = addChunk_PLTE(&outv, &info.color); - if(state->error) goto cleanup; - } - if(state->encoder.force_palette && (info.color.colortype == LCT_RGB || info.color.colortype == LCT_RGBA)) { - /*force_palette means: write suggested palette for truecolor in PLTE chunk*/ - state->error = addChunk_PLTE(&outv, &info.color); - if(state->error) goto cleanup; - } - /*tRNS (this will only add if when necessary) */ - state->error = addChunk_tRNS(&outv, &info.color); - if(state->error) goto cleanup; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /*bKGD (must come between PLTE and the IDAt chunks*/ - if(info.background_defined) { - state->error = addChunk_bKGD(&outv, &info); - if(state->error) goto cleanup; - } - /*pHYs (must come before the IDAT chunks)*/ - if(info.phys_defined) { - state->error = addChunk_pHYs(&outv, &info); - if(state->error) goto cleanup; - } - - /*unknown chunks between PLTE and IDAT*/ - if(info.unknown_chunks_data[1]) { - state->error = addUnknownChunks(&outv, info.unknown_chunks_data[1], info.unknown_chunks_size[1]); - if(state->error) goto cleanup; - } -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - /*IDAT (multiple IDAT chunks must be consecutive)*/ - state->error = addChunk_IDAT(&outv, data, datasize, &state->encoder.zlibsettings); - if(state->error) goto cleanup; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /*tIME*/ - if(info.time_defined) { - state->error = addChunk_tIME(&outv, &info.time); - if(state->error) goto cleanup; - } - /*tEXt and/or zTXt*/ - for(i = 0; i != info.text_num; ++i) { - if(lodepng_strlen(info.text_keys[i]) > 79) { - state->error = 66; /*text chunk too large*/ - goto cleanup; - } - if(lodepng_strlen(info.text_keys[i]) < 1) { - state->error = 67; /*text chunk too small*/ - goto cleanup; - } - if(state->encoder.text_compression) { - state->error = addChunk_zTXt(&outv, info.text_keys[i], info.text_strings[i], &state->encoder.zlibsettings); - if(state->error) goto cleanup; - } else { - state->error = addChunk_tEXt(&outv, info.text_keys[i], info.text_strings[i]); - if(state->error) goto cleanup; - } - } - /*LodePNG version id in text chunk*/ - if(state->encoder.add_id) { - unsigned already_added_id_text = 0; - for(i = 0; i != info.text_num; ++i) { - const char* k = info.text_keys[i]; - /* Could use strcmp, but we're not calling or reimplementing this C library function for this use only */ - if(k[0] == 'L' && k[1] == 'o' && k[2] == 'd' && k[3] == 'e' && - k[4] == 'P' && k[5] == 'N' && k[6] == 'G' && k[7] == '\0') { - already_added_id_text = 1; - break; - } - } - if(already_added_id_text == 0) { - state->error = addChunk_tEXt(&outv, "LodePNG", LODEPNG_VERSION_STRING); /*it's shorter as tEXt than as zTXt chunk*/ - if(state->error) goto cleanup; - } - } - /*iTXt*/ - for(i = 0; i != info.itext_num; ++i) { - if(lodepng_strlen(info.itext_keys[i]) > 79) { - state->error = 66; /*text chunk too large*/ - goto cleanup; - } - if(lodepng_strlen(info.itext_keys[i]) < 1) { - state->error = 67; /*text chunk too small*/ - goto cleanup; - } - state->error = addChunk_iTXt( - &outv, state->encoder.text_compression, - info.itext_keys[i], info.itext_langtags[i], info.itext_transkeys[i], info.itext_strings[i], - &state->encoder.zlibsettings); - if(state->error) goto cleanup; - } - - /*unknown chunks between IDAT and IEND*/ - if(info.unknown_chunks_data[2]) { - state->error = addUnknownChunks(&outv, info.unknown_chunks_data[2], info.unknown_chunks_size[2]); - if(state->error) goto cleanup; - } -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - state->error = addChunk_IEND(&outv); - if(state->error) goto cleanup; - } - -cleanup: - lodepng_info_cleanup(&info); - lodepng_free(data); - lodepng_color_mode_cleanup(&auto_color); - - /*instead of cleaning the vector up, give it to the output*/ - *out = outv.data; - *outsize = outv.size; - - return state->error; -} - -unsigned lodepng_encode_memory(unsigned char** out, size_t* outsize, const unsigned char* image, - unsigned w, unsigned h, LodePNGColorType colortype, unsigned bitdepth) { - unsigned error; - LodePNGState state; - lodepng_state_init(&state); - state.info_raw.colortype = colortype; - state.info_raw.bitdepth = bitdepth; - state.info_png.color.colortype = colortype; - state.info_png.color.bitdepth = bitdepth; - lodepng_encode(out, outsize, image, w, h, &state); - error = state.error; - lodepng_state_cleanup(&state); - return error; -} - -unsigned lodepng_encode32(unsigned char** out, size_t* outsize, const unsigned char* image, unsigned w, unsigned h) { - return lodepng_encode_memory(out, outsize, image, w, h, LCT_RGBA, 8); -} - -unsigned lodepng_encode24(unsigned char** out, size_t* outsize, const unsigned char* image, unsigned w, unsigned h) { - return lodepng_encode_memory(out, outsize, image, w, h, LCT_RGB, 8); -} - -#ifdef LODEPNG_COMPILE_DISK -unsigned lodepng_encode_file(const char* filename, const unsigned char* image, unsigned w, unsigned h, - LodePNGColorType colortype, unsigned bitdepth) { - unsigned char* buffer; - size_t buffersize; - unsigned error = lodepng_encode_memory(&buffer, &buffersize, image, w, h, colortype, bitdepth); - if(!error) error = lodepng_save_file(buffer, buffersize, filename); - lodepng_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, LCT_RGBA, 8); -} - -unsigned lodepng_encode24_file(const char* filename, const unsigned char* image, unsigned w, unsigned h) { - return lodepng_encode_file(filename, image, w, h, LCT_RGB, 8); -} -#endif /*LODEPNG_COMPILE_DISK*/ - -void lodepng_encoder_settings_init(LodePNGEncoderSettings* settings) { - lodepng_compress_settings_init(&settings->zlibsettings); - settings->filter_palette_zero = 1; - settings->filter_strategy = LFS_MINSUM; - settings->auto_convert = 1; - settings->force_palette = 0; - settings->predefined_filters = 0; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - settings->add_id = 0; - settings->text_compression = 1; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -} - -#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"; - /*this error could happen if there are only 0 or 1 symbols present in the huffman code:*/ - case 16: return "invalid 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 small or too big"; /*0, or more than 256 colors*/ - case 39: return "tRNS chunk before PLTE or has more entries than palette size"; - case 40: return "tRNS chunk has wrong size for grayscale 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 grayscale image"; - case 45: return "bKGD chunk has wrong size for RGB image"; - case 48: return "empty input buffer given to decoder. Maybe caused by non-existing file?"; - 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"; - case 54: return "repeat symbol in tree while there was no value symbol yet"; - /*jumped past tree while generating huffman tree, this could be when the - tree will have more leaves than symbols after generating it out of the - given lengths. 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 "requested color conversion not supported"; - case 60: return "invalid window size given in the settings of the encoder (must be 0-32768)"; - case 61: return "invalid BTYPE given in the settings of the encoder (only 0, 1 and 2 are allowed)"; - /*LodePNG leaves the choice of RGB to grayscale conversion formula to the user.*/ - case 62: return "conversion from color to grayscale not supported"; - /*(2^31-1)*/ - case 63: return "length of a chunk too long, max allowed for PNG is 2147483647 bytes per chunk"; - /*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 "invalid interlace mode given to encoder (must be 0 or 1)"; - case 72: return "while decoding, invalid 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"; - case 82: return "color conversion to palette requested while a color isn't in palette, or index out of bounds"; - case 83: return "memory allocation failed"; - case 84: return "given image too small to contain all pixels to be encoded"; - case 86: return "impossible offset in lz77 encoding (internal bug)"; - case 87: return "must provide custom zlib function pointer if LODEPNG_COMPILE_ZLIB is not defined"; - case 88: return "invalid filter strategy given for LodePNGEncoderSettings.filter_strategy"; - case 89: return "text chunk keyword too short or long: must have size 1-79"; - /*the windowsize in the LodePNGCompressSettings. Requiring POT(==> & instead of %) makes encoding 12% faster.*/ - case 90: return "windowsize must be a power of two"; - case 91: return "invalid decompressed idat size"; - case 92: return "integer overflow due to too many pixels"; - case 93: return "zero width or height is invalid"; - case 94: return "header chunk must have a size of 13 bytes"; - case 95: return "integer overflow with combined idat chunk size"; - case 96: return "invalid gAMA chunk size"; - case 97: return "invalid cHRM chunk size"; - case 98: return "invalid sRGB chunk size"; - case 99: return "invalid sRGB rendering intent"; - case 100: return "invalid ICC profile color type, the PNG specification only allows RGB or GRAY"; - case 101: return "PNG specification does not allow RGB ICC profile on gray color types and vice versa"; - case 102: return "not allowed to set grayscale ICC profile with colored pixels by PNG specification"; - case 103: return "invalid palette index in bKGD chunk. Maybe it came before PLTE chunk?"; - case 104: return "invalid bKGD color while encoding (e.g. palette index out of range)"; - case 105: return "integer overflow of bitsize"; - case 106: return "PNG file must have PLTE chunk if color type is palette"; - case 107: return "color convert from palette mode requested without setting the palette data in it"; - case 108: return "tried to add more than 256 values to a palette"; - /*this limit can be configured in LodePNGDecompressSettings*/ - case 109: return "tried to decompress zlib or deflate data larger than desired max_output_size"; - case 110: return "custom zlib or inflate decompression failed"; - case 111: return "custom zlib or deflate compression failed"; - /*max text size limit can be configured in LodePNGDecoderSettings. This error prevents - unreasonable memory consumption when decoding due to impossibly large text sizes.*/ - case 112: return "compressed text unreasonably large"; - /*max ICC size limit can be configured in LodePNGDecoderSettings. This error prevents - unreasonable memory consumption when decoding due to impossibly large ICC profile*/ - case 113: return "ICC profile unreasonably large"; - case 114: return "sBIT chunk has wrong size for the color type of the image"; - case 115: return "sBIT value out of range"; - } - return "unknown error code"; -} -#endif /*LODEPNG_COMPILE_ERROR_TEXT*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* // C++ Wrapper // */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_CPP -namespace lodepng { - -#ifdef LODEPNG_COMPILE_DISK -unsigned load_file(std::vector<unsigned char>& buffer, const std::string& filename) { - long size = lodepng_filesize(filename.c_str()); - if(size < 0) return 78; - buffer.resize((size_t)size); - return size == 0 ? 0 : lodepng_buffer_file(&buffer[0], (size_t)size, filename.c_str()); -} - -/*write given buffer to the file, overwriting the file, it doesn't append to it.*/ -unsigned save_file(const std::vector<unsigned char>& buffer, const std::string& filename) { - return lodepng_save_file(buffer.empty() ? 0 : &buffer[0], buffer.size(), filename.c_str()); -} -#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 LodePNGDecompressSettings& settings) { - unsigned char* buffer = 0; - size_t buffersize = 0; - unsigned error = zlib_decompress(&buffer, &buffersize, 0, in, insize, &settings); - if(buffer) { - out.insert(out.end(), buffer, &buffer[buffersize]); - lodepng_free(buffer); - } - return error; -} - -unsigned decompress(std::vector<unsigned char>& out, const std::vector<unsigned char>& in, - const LodePNGDecompressSettings& settings) { - return decompress(out, in.empty() ? 0 : &in[0], in.size(), settings); -} -#endif /* LODEPNG_COMPILE_DECODER */ - -#ifdef LODEPNG_COMPILE_ENCODER -unsigned compress(std::vector<unsigned char>& out, const unsigned char* in, size_t insize, - const LodePNGCompressSettings& settings) { - unsigned char* buffer = 0; - size_t buffersize = 0; - unsigned error = zlib_compress(&buffer, &buffersize, in, insize, &settings); - if(buffer) { - out.insert(out.end(), buffer, &buffer[buffersize]); - lodepng_free(buffer); - } - return error; -} - -unsigned compress(std::vector<unsigned char>& out, const std::vector<unsigned char>& in, - const LodePNGCompressSettings& settings) { - return compress(out, in.empty() ? 0 : &in[0], in.size(), settings); -} -#endif /* LODEPNG_COMPILE_ENCODER */ -#endif /* LODEPNG_COMPILE_ZLIB */ - - -#ifdef LODEPNG_COMPILE_PNG - -State::State() { - lodepng_state_init(this); -} - -State::State(const State& other) { - lodepng_state_init(this); - lodepng_state_copy(this, &other); -} - -State::~State() { - lodepng_state_cleanup(this); -} - -State& State::operator=(const State& other) { - lodepng_state_copy(this, &other); - return *this; -} - -#ifdef LODEPNG_COMPILE_DECODER - -unsigned decode(std::vector<unsigned char>& out, unsigned& w, unsigned& h, const unsigned char* in, - size_t insize, LodePNGColorType colortype, unsigned bitdepth) { - unsigned char* buffer = 0; - unsigned error = lodepng_decode_memory(&buffer, &w, &h, in, insize, colortype, bitdepth); - if(buffer && !error) { - State state; - state.info_raw.colortype = colortype; - state.info_raw.bitdepth = bitdepth; - size_t buffersize = lodepng_get_raw_size(w, h, &state.info_raw); - out.insert(out.end(), buffer, &buffer[buffersize]); - } - lodepng_free(buffer); - return error; -} - -unsigned decode(std::vector<unsigned char>& out, unsigned& w, unsigned& h, - const std::vector<unsigned char>& in, LodePNGColorType colortype, unsigned bitdepth) { - return decode(out, w, h, in.empty() ? 0 : &in[0], (unsigned)in.size(), colortype, bitdepth); -} - -unsigned decode(std::vector<unsigned char>& out, unsigned& w, unsigned& h, - State& state, - const unsigned char* in, size_t insize) { - unsigned char* buffer = NULL; - unsigned error = lodepng_decode(&buffer, &w, &h, &state, in, insize); - if(buffer && !error) { - size_t buffersize = lodepng_get_raw_size(w, h, &state.info_raw); - out.insert(out.end(), buffer, &buffer[buffersize]); - } - lodepng_free(buffer); - return error; -} - -unsigned decode(std::vector<unsigned char>& out, unsigned& w, unsigned& h, - State& state, - const std::vector<unsigned char>& in) { - return decode(out, w, h, state, in.empty() ? 0 : &in[0], in.size()); -} - -#ifdef LODEPNG_COMPILE_DISK -unsigned decode(std::vector<unsigned char>& out, unsigned& w, unsigned& h, const std::string& filename, - LodePNGColorType colortype, unsigned bitdepth) { - std::vector<unsigned char> buffer; - /* safe output values in case error happens */ - w = h = 0; - unsigned error = load_file(buffer, filename); - if(error) return error; - 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, - LodePNGColorType colortype, unsigned bitdepth) { - unsigned char* buffer; - size_t buffersize; - unsigned error = lodepng_encode_memory(&buffer, &buffersize, in, w, h, colortype, bitdepth); - if(buffer) { - out.insert(out.end(), buffer, &buffer[buffersize]); - lodepng_free(buffer); - } - return error; -} - -unsigned encode(std::vector<unsigned char>& out, - const std::vector<unsigned char>& in, unsigned w, unsigned h, - LodePNGColorType colortype, unsigned bitdepth) { - if(lodepng_get_raw_size_lct(w, h, colortype, bitdepth) > in.size()) return 84; - return encode(out, in.empty() ? 0 : &in[0], w, h, colortype, bitdepth); -} - -unsigned encode(std::vector<unsigned char>& out, - const unsigned char* in, unsigned w, unsigned h, - State& state) { - unsigned char* buffer; - size_t buffersize; - unsigned error = lodepng_encode(&buffer, &buffersize, in, w, h, &state); - if(buffer) { - out.insert(out.end(), buffer, &buffer[buffersize]); - lodepng_free(buffer); - } - return error; -} - -unsigned encode(std::vector<unsigned char>& out, - const std::vector<unsigned char>& in, unsigned w, unsigned h, - State& state) { - if(lodepng_get_raw_size(w, h, &state.info_raw) > in.size()) return 84; - return encode(out, in.empty() ? 0 : &in[0], w, h, state); -} - -#ifdef LODEPNG_COMPILE_DISK -unsigned encode(const std::string& filename, - const unsigned char* in, unsigned w, unsigned h, - LodePNGColorType colortype, unsigned bitdepth) { - std::vector<unsigned char> buffer; - unsigned error = encode(buffer, in, w, h, colortype, bitdepth); - if(!error) error = save_file(buffer, filename); - return error; -} - -unsigned encode(const std::string& filename, - const std::vector<unsigned char>& in, unsigned w, unsigned h, - LodePNGColorType colortype, unsigned bitdepth) { - if(lodepng_get_raw_size_lct(w, h, colortype, bitdepth) > in.size()) return 84; - return encode(filename, in.empty() ? 0 : &in[0], w, h, colortype, bitdepth); -} -#endif /* LODEPNG_COMPILE_DISK */ -#endif /* LODEPNG_COMPILE_ENCODER */ -#endif /* LODEPNG_COMPILE_PNG */ -} /* namespace lodepng */ -#endif /*LODEPNG_COMPILE_CPP*/ |