diff options
Diffstat (limited to 'src/zopflipng/lodepng/lodepng.h')
| -rw-r--r-- | src/zopflipng/lodepng/lodepng.h | 138 |
1 files changed, 80 insertions, 58 deletions
diff --git a/src/zopflipng/lodepng/lodepng.h b/src/zopflipng/lodepng/lodepng.h index c5363a4..6801cb7 100644 --- a/src/zopflipng/lodepng/lodepng.h +++ b/src/zopflipng/lodepng/lodepng.h @@ -1,7 +1,7 @@ /* -LodePNG version 20191107 +LodePNG version 20201017 -Copyright (c) 2005-2019 Lode Vandevenne +Copyright (c) 2005-2020 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 @@ -270,12 +270,21 @@ struct LodePNGDecompressSettings { unsigned ignore_adler32; /*if 1, continue and don't give an error message if the Adler32 checksum is corrupted*/ unsigned ignore_nlen; /*ignore complement of len checksum in uncompressed blocks*/ - /*use custom zlib decoder instead of built in one (default: null)*/ + /*Maximum decompressed size, beyond this the decoder may (and is encouraged to) stop decoding, + return an error, output a data size > max_output_size and all the data up to that point. This is + not hard limit nor a guarantee, but can prevent excessive memory usage. This setting is + ignored by the PNG decoder, but is used by the deflate/zlib decoder and can be used by custom ones. + Set to 0 to impose no limit (the default).*/ + size_t max_output_size; + + /*use custom zlib decoder instead of built in one (default: null). + Should return 0 if success, any non-0 if error (numeric value not exposed).*/ unsigned (*custom_zlib)(unsigned char**, size_t*, const unsigned char*, size_t, const LodePNGDecompressSettings*); /*use custom deflate decoder instead of built in one (default: null) - if custom_zlib is not null, custom_inflate is ignored (the zlib format uses deflate)*/ + if custom_zlib is not null, custom_inflate is ignored (the zlib format uses deflate). + Should return 0 if success, any non-0 if error (numeric value not exposed).*/ unsigned (*custom_inflate)(unsigned char**, size_t*, const unsigned char*, size_t, const LodePNGDecompressSettings*); @@ -346,8 +355,8 @@ typedef struct LodePNGColorMode { The palette is only supported for color type 3. */ - unsigned char* palette; /*palette in RGBARGBA... order. When allocated, must be either 0, or have size 1024*/ - size_t palettesize; /*palette size in number of colors (amount of bytes is 4 * palettesize)*/ + unsigned char* palette; /*palette in RGBARGBA... order. Must be either 0, or when allocated must have 1024 bytes*/ + size_t palettesize; /*palette size in number of colors (amount of used bytes is 4 * palettesize)*/ /* transparent color key (tRNS) @@ -454,30 +463,36 @@ typedef struct LodePNGInfo { unsigned background_b; /*blue component of suggested background color*/ /* - non-international text chunks (tEXt and zTXt) + Non-international text chunks (tEXt and zTXt) The char** arrays each contain num strings. The actual messages are in text_strings, while text_keys are keywords that give a short description what the actual text represents, e.g. Title, Author, Description, or anything else. - All the string fields below including keys, names and language tags are null terminated. + All the string fields below including strings, keys, names and language tags are null terminated. The PNG specification uses null characters for the keys, names and tags, and forbids null characters to appear in the main text which is why we can use null termination everywhere here. - A keyword is minimum 1 character and maximum 79 characters long. It's - discouraged to use a single line length longer than 79 characters for texts. + A keyword is minimum 1 character and maximum 79 characters long (plus the + additional null terminator). It's discouraged to use a single line length + longer than 79 characters for texts. Don't allocate these text buffers yourself. Use the init/cleanup functions correctly and use lodepng_add_text and lodepng_clear_text. + + Standard text chunk keywords and strings are encoded using Latin-1. */ size_t text_num; /*the amount of texts in these char** buffers (there may be more texts in itext)*/ char** text_keys; /*the keyword of a text chunk (e.g. "Comment")*/ char** text_strings; /*the actual text*/ /* - international text chunks (iTXt) + International text chunks (iTXt) Similar to the non-international text chunks, but with additional strings - "langtags" and "transkeys". + "langtags" and "transkeys", and the following text encodings are used: + keys: Latin-1, langtags: ASCII, transkeys and strings: UTF-8. + keys must be 1-79 characters (plus the additional null terminator), the other + strings are any length. */ size_t itext_num; /*the amount of international texts in this PNG*/ char** itext_keys; /*the English keyword of the text chunk (e.g. "Comment")*/ @@ -639,8 +654,19 @@ typedef struct LodePNGDecoderSettings { #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS unsigned read_text_chunks; /*if false but remember_unknown_chunks is true, they're stored in the unknown chunks*/ + /*store all bytes from unknown chunks in the LodePNGInfo (off by default, useful for a png editor)*/ unsigned remember_unknown_chunks; + + /* maximum size for decompressed text chunks. If a text chunk's text is larger than this, an error is returned, + unless reading text chunks is disabled or this limit is set higher or disabled. Set to 0 to allow any size. + By default it is a value that prevents unreasonably large strings from hogging memory. */ + size_t max_text_size; + + /* maximum size for compressed ICC chunks. If the ICC profile is larger than this, an error will be returned. Set to + 0 to allow any size. By default this is a value that prevents ICC profiles that would be much larger than any + legitimate profile could be to hog memory. */ + size_t max_icc_size; #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ } LodePNGDecoderSettings; @@ -693,20 +719,11 @@ typedef struct LodePNGColorStats { void lodepng_color_stats_init(LodePNGColorStats* stats); -/*Get a LodePNGColorStats of the image. The stats must already have been inited.*/ -void lodepng_compute_color_stats(LodePNGColorStats* stats, - const unsigned char* image, unsigned w, unsigned h, - const LodePNGColorMode* mode_in); -/*Computes a minimal PNG color model that can contain all colors as indicated by the stats and it settings. -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, ... -LodePNG uses this function internally if auto_convert is enabled (it is by default). -*/ -unsigned lodepng_auto_choose_color(LodePNGColorMode* mode_out, - const LodePNGColorMode* mode_in, - const LodePNGColorMode* stats); +/*Get a LodePNGColorStats of the image. The stats must already have been inited. +Returns error code (e.g. alloc fail) or 0 if ok.*/ +unsigned lodepng_compute_color_stats(LodePNGColorStats* stats, + const unsigned char* image, unsigned w, unsigned h, + const LodePNGColorMode* mode_in); /*Settings for the encoder.*/ typedef struct LodePNGEncoderSettings { @@ -755,10 +772,6 @@ typedef struct LodePNGState { LodePNGColorMode info_raw; /*specifies the format in which you would like to get the raw pixel buffer*/ LodePNGInfo info_png; /*info of the PNG image obtained after decoding*/ unsigned error; -#ifdef LODEPNG_COMPILE_CPP - /* For the lodepng::State subclass. */ - virtual ~LodePNGState(){} -#endif } LodePNGState; /*init, cleanup and copy functions to use with this struct*/ @@ -870,32 +883,32 @@ Input must be at the beginning of a chunk (result of a previous lodepng_chunk_ne or the 8th byte of a PNG file which always has the first chunk), or alternatively may point to the first byte of the PNG file (which is not a chunk but the magic header, the function will then skip over it and return the first real chunk). -Expects at least 8 readable bytes of memory in the input pointer. -Will output pointer to the start of the next chunk or the end of the file if there -is no more chunk after this. Start this process at the 8th byte of the PNG file. +Will output pointer to the start of the next chunk, or at or beyond end of the file if there +is no more chunk after this or possibly if the chunk is corrupt. +Start this process at the 8th byte of the PNG file. In a non-corrupt PNG file, the last chunk should have name "IEND". */ -unsigned char* lodepng_chunk_next(unsigned char* chunk); -const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk); +unsigned char* lodepng_chunk_next(unsigned char* chunk, unsigned char* end); +const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk, const unsigned char* end); /*Finds the first chunk with the given type in the range [chunk, end), or returns NULL if not found.*/ -unsigned char* lodepng_chunk_find(unsigned char* chunk, const unsigned char* end, const char type[5]); +unsigned char* lodepng_chunk_find(unsigned char* chunk, unsigned char* end, const char type[5]); const unsigned char* lodepng_chunk_find_const(const unsigned char* chunk, const unsigned char* end, const char type[5]); /* Appends chunk to the data in out. The given chunk should already have its chunk header. -The out variable and outlength are updated to reflect the new reallocated buffer. +The out variable and outsize are updated to reflect the new reallocated buffer. Returns error code (0 if it went ok) */ -unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk); +unsigned lodepng_chunk_append(unsigned char** out, size_t* outsize, const unsigned char* chunk); /* Appends new chunk to out. The chunk to append is given by giving its length, type and data separately. The type is a 4-letter string. -The out variable and outlength are updated to reflect the new reallocated buffer. +The out variable and outsize are updated to reflect the new reallocated buffer. Returne error code (0 if it went ok) */ -unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length, +unsigned lodepng_chunk_create(unsigned char** out, size_t* outsize, unsigned length, const char* type, const unsigned char* data); @@ -985,7 +998,7 @@ class State : public LodePNGState { public: State(); State(const State& other); - virtual ~State(); + ~State(); State& operator=(const State& other); }; @@ -1067,8 +1080,7 @@ TODO: [ ] let the C++ wrapper catch exceptions coming from the standard library and return LodePNG error codes [ ] allow user to provide custom color conversion functions, e.g. for premultiplied alpha, padding bits or not, ... [ ] allow user to give data (void*) to custom allocator -[ ] provide alternatives for C library functions not present on some platforms (memcpy, ...) -[ ] rename "grey" to "gray" everywhere since "color" also uses US spelling (keep "grey" copies for backwards compatibility) +[X] provide alternatives for C library functions not present on some platforms (memcpy, ...) */ #endif /*LODEPNG_H inclusion guard*/ @@ -1519,6 +1531,11 @@ of the error in English as a string. Check the implementation of lodepng_error_text to see the meaning of each code. +It is not recommended to use the numerical values to programmatically make +different decisions based on error types as the numbers are not guaranteed to +stay backwards compatible. They are for human consumption only. Programmatically +only 0 or non-0 matter. + 8. chunks and PNG editing ------------------------- @@ -1584,12 +1601,12 @@ Iterate to the next chunk. This works if you have a buffer with consecutive chun functions do no boundary checking of the allocated data whatsoever, so make sure there is enough data available in the buffer to be able to go to the next chunk. -unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk): -unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length, +unsigned lodepng_chunk_append(unsigned char** out, size_t* outsize, const unsigned char* chunk): +unsigned lodepng_chunk_create(unsigned char** out, size_t* outsize, unsigned length, const char* type, const unsigned char* data): These functions are used to create new chunks that are appended to the data in *out that has -length *outlength. The append function appends an existing chunk to the new data. The create +length *outsize. The append function appends an existing chunk to the new data. The create function creates a new chunk with the given parameters and appends it. Type is the 4-letter name of the chunk. @@ -1789,14 +1806,19 @@ symbol. Not all changes are listed here, the commit history in github lists more: https://github.com/lvandeve/lodepng +*) 17 okt 2020: prevent decoding too large text/icc chunks by default. +*) 06 mar 2020: simplified some of the dynamic memory allocations. +*) 12 jan 2020: (!) added 'end' argument to lodepng_chunk_next to allow correct + overflow checks. *) 14 aug 2019: around 25% faster decoding thanks to huffman lookup tables. -*) 15 jun 2019 (!): auto_choose_color API changed (for bugfix: don't use palette - if gray ICC profile) and non-ICC LodePNGColorProfile renamed to LodePNGColorStats. +*) 15 jun 2019: (!) auto_choose_color API changed (for bugfix: don't use palette + if gray ICC profile) and non-ICC LodePNGColorProfile renamed to + LodePNGColorStats. *) 30 dec 2018: code style changes only: removed newlines before opening braces. *) 10 sep 2018: added way to inspect metadata chunks without full decoding. -*) 19 aug 2018 (!): fixed color mode bKGD is encoded with and made it use +*) 19 aug 2018: (!) fixed color mode bKGD is encoded with and made it use palette index in case of palette. -*) 10 aug 2018 (!): added support for gAMA, cHRM, sRGB and iCCP chunks. This +*) 10 aug 2018: (!) added support for gAMA, cHRM, sRGB and iCCP chunks. This change is backwards compatible unless you relied on unknown_chunks for those. *) 11 jun 2018: less restrictive check for pixel size integer overflow *) 14 jan 2018: allow optionally ignoring a few more recoverable errors @@ -1816,25 +1838,25 @@ https://github.com/lvandeve/lodepng *) 22 dec 2013: Power of two windowsize required for optimization. *) 15 apr 2013: Fixed bug with LAC_ALPHA and color key. *) 25 mar 2013: Added an optional feature to ignore some PNG errors (fix_png). -*) 11 mar 2013 (!): Bugfix with custom free. Changed from "my" to "lodepng_" +*) 11 mar 2013: (!) Bugfix with custom free. Changed from "my" to "lodepng_" prefix for the custom allocators and made it possible with a new #define to use custom ones in your project without needing to change lodepng's code. *) 28 jan 2013: Bugfix with color key. *) 27 okt 2012: Tweaks in text chunk keyword length error handling. -*) 8 okt 2012 (!): Added new filter strategy (entropy) and new auto color mode. +*) 8 okt 2012: (!) Added new filter strategy (entropy) and new auto color mode. (no palette). Better deflate tree encoding. New compression tweak settings. Faster color conversions while decoding. Some internal cleanups. *) 23 sep 2012: Reduced warnings in Visual Studio a little bit. -*) 1 sep 2012 (!): Removed #define's for giving custom (de)compression functions +*) 1 sep 2012: (!) Removed #define's for giving custom (de)compression functions and made it work with function pointers instead. *) 23 jun 2012: Added more filter strategies. Made it easier to use custom alloc and free functions and toggle #defines from compiler flags. Small fixes. -*) 6 may 2012 (!): Made plugging in custom zlib/deflate functions more flexible. -*) 22 apr 2012 (!): Made interface more consistent, renaming a lot. Removed +*) 6 may 2012: (!) Made plugging in custom zlib/deflate functions more flexible. +*) 22 apr 2012: (!) Made interface more consistent, renaming a lot. Removed redundant C++ codec classes. Reduced amount of structs. Everything changed, but it is cleaner now imho and functionality remains the same. Also fixed several bugs and shrunk the implementation code. Made new samples. -*) 6 nov 2011 (!): By default, the encoder now automatically chooses the best +*) 6 nov 2011: (!) By default, the encoder now automatically chooses the best PNG color model and bit depth, based on the amount and type of colors of the raw image. For this, autoLeaveOutAlphaChannel replaced by auto_choose_color. *) 9 okt 2011: simpler hash chain implementation for the encoder. @@ -1843,7 +1865,7 @@ https://github.com/lvandeve/lodepng A bug with the PNG filtertype heuristic was fixed, so that it chooses much better ones (it's quite significant). A setting to do an experimental, slow, brute force search for PNG filter types is added. -*) 17 aug 2011 (!): changed some C zlib related function names. +*) 17 aug 2011: (!) changed some C zlib related function names. *) 16 aug 2011: made the code less wide (max 120 characters per line). *) 17 apr 2011: code cleanup. Bugfixes. Convert low to 16-bit per sample colors. *) 21 feb 2011: fixed compiling for C90. Fixed compiling with sections disabled. @@ -1951,5 +1973,5 @@ Domain: gmail dot com. Account: lode dot vandevenne. -Copyright (c) 2005-2019 Lode Vandevenne +Copyright (c) 2005-2020 Lode Vandevenne */ |