lpc4088_ebb_gui_cube - Graphical demo for the LPC4088 Experiment Base Bo…

Users » embeddedartists » Code » lpc4088_ebb_gui_cube

EmbeddedArtists AB / Mbed 2 deprecated lpc4088_ebb_gui_cube

Graphical demo for the LPC4088 Experiment Base Board with one of the Display Expansion Kits. This demo shows a rotating 3D cube with and without textures.

Dependencies: EALib mbed

lodepng.h@0:c828045bbe69, 2014-10-03 (annotated)

Committer:: embeddedartists
Date:: Fri Oct 03 12:48:37 2014 +0000
Revision:: 0:c828045bbe69

First version.

Who changed what in which revision?

User	Revision	Line number	New contents of line
embeddedartists	0:c828045bbe69	1	/*
embeddedartists	0:c828045bbe69	2	LodePNG version 20131222
embeddedartists	0:c828045bbe69	3
embeddedartists	0:c828045bbe69	4	Copyright (c) 2005-2013 Lode Vandevenne
embeddedartists	0:c828045bbe69	5
embeddedartists	0:c828045bbe69	6	This software is provided 'as-is', without any express or implied
embeddedartists	0:c828045bbe69	7	warranty. In no event will the authors be held liable for any damages
embeddedartists	0:c828045bbe69	8	arising from the use of this software.
embeddedartists	0:c828045bbe69	9
embeddedartists	0:c828045bbe69	10	Permission is granted to anyone to use this software for any purpose,
embeddedartists	0:c828045bbe69	11	including commercial applications, and to alter it and redistribute it
embeddedartists	0:c828045bbe69	12	freely, subject to the following restrictions:
embeddedartists	0:c828045bbe69	13
embeddedartists	0:c828045bbe69	14	1. The origin of this software must not be misrepresented; you must not
embeddedartists	0:c828045bbe69	15	claim that you wrote the original software. If you use this software
embeddedartists	0:c828045bbe69	16	in a product, an acknowledgment in the product documentation would be
embeddedartists	0:c828045bbe69	17	appreciated but is not required.
embeddedartists	0:c828045bbe69	18
embeddedartists	0:c828045bbe69	19	2. Altered source versions must be plainly marked as such, and must not be
embeddedartists	0:c828045bbe69	20	misrepresented as being the original software.
embeddedartists	0:c828045bbe69	21
embeddedartists	0:c828045bbe69	22	3. This notice may not be removed or altered from any source
embeddedartists	0:c828045bbe69	23	distribution.
embeddedartists	0:c828045bbe69	24	*/
embeddedartists	0:c828045bbe69	25
embeddedartists	0:c828045bbe69	26	#ifndef LODEPNG_H
embeddedartists	0:c828045bbe69	27	#define LODEPNG_H
embeddedartists	0:c828045bbe69	28
embeddedartists	0:c828045bbe69	29	#include <string.h> /for size_t/
embeddedartists	0:c828045bbe69	30
embeddedartists	0:c828045bbe69	31	#ifdef __cplusplus
embeddedartists	0:c828045bbe69	32	#include <vector>
embeddedartists	0:c828045bbe69	33	#include <string>
embeddedartists	0:c828045bbe69	34	#endif /__cplusplus/
embeddedartists	0:c828045bbe69	35
embeddedartists	0:c828045bbe69	36
embeddedartists	0:c828045bbe69	37	// Settings modified by Embedded Artists
embeddedartists	0:c828045bbe69	38	#define LODEPNG_NO_COMPILE_ENCODER
embeddedartists	0:c828045bbe69	39	#define LODEPNG_NO_COMPILE_DISK
embeddedartists	0:c828045bbe69	40	#define LODEPNG_NO_COMPILE_ANCILLARY_CHUNKS
embeddedartists	0:c828045bbe69	41	#define LODEPNG_NO_COMPILE_ERROR_TEXT
embeddedartists	0:c828045bbe69	42	#define LODEPNG_NO_COMPILE_CPP
embeddedartists	0:c828045bbe69	43
embeddedartists	0:c828045bbe69	44
embeddedartists	0:c828045bbe69	45	/*
embeddedartists	0:c828045bbe69	46	The following #defines are used to create code sections. They can be disabled
embeddedartists	0:c828045bbe69	47	to disable code sections, which can give faster compile time and smaller binary.
embeddedartists	0:c828045bbe69	48	The "NO_COMPILE" defines are designed to be used to pass as defines to the
embeddedartists	0:c828045bbe69	49	compiler command to disable them without modifying this header, e.g.
embeddedartists	0:c828045bbe69	50	-DLODEPNG_NO_COMPILE_ZLIB for gcc.
embeddedartists	0:c828045bbe69	51	*/
embeddedartists	0:c828045bbe69	52	/*deflate & zlib. If disabled, you must specify alternative zlib functions in
embeddedartists	0:c828045bbe69	53	the custom_zlib field of the compress and decompress settings*/
embeddedartists	0:c828045bbe69	54	#ifndef LODEPNG_NO_COMPILE_ZLIB
embeddedartists	0:c828045bbe69	55	#define LODEPNG_COMPILE_ZLIB
embeddedartists	0:c828045bbe69	56	#endif
embeddedartists	0:c828045bbe69	57	/png encoder and png decoder/
embeddedartists	0:c828045bbe69	58	#ifndef LODEPNG_NO_COMPILE_PNG
embeddedartists	0:c828045bbe69	59	#define LODEPNG_COMPILE_PNG
embeddedartists	0:c828045bbe69	60	#endif
embeddedartists	0:c828045bbe69	61	/deflate&zlib decoder and png decoder/
embeddedartists	0:c828045bbe69	62	#ifndef LODEPNG_NO_COMPILE_DECODER
embeddedartists	0:c828045bbe69	63	#define LODEPNG_COMPILE_DECODER
embeddedartists	0:c828045bbe69	64	#endif
embeddedartists	0:c828045bbe69	65	/deflate&zlib encoder and png encoder/
embeddedartists	0:c828045bbe69	66	#ifndef LODEPNG_NO_COMPILE_ENCODER
embeddedartists	0:c828045bbe69	67	#define LODEPNG_COMPILE_ENCODER
embeddedartists	0:c828045bbe69	68	#endif
embeddedartists	0:c828045bbe69	69	/the optional built in harddisk file loading and saving functions/
embeddedartists	0:c828045bbe69	70	#ifndef LODEPNG_NO_COMPILE_DISK
embeddedartists	0:c828045bbe69	71	#define LODEPNG_COMPILE_DISK
embeddedartists	0:c828045bbe69	72	#endif
embeddedartists	0:c828045bbe69	73	/support for chunks other than IHDR, IDAT, PLTE, tRNS, IEND: ancillary and unknown chunks/
embeddedartists	0:c828045bbe69	74	#ifndef LODEPNG_NO_COMPILE_ANCILLARY_CHUNKS
embeddedartists	0:c828045bbe69	75	#define LODEPNG_COMPILE_ANCILLARY_CHUNKS
embeddedartists	0:c828045bbe69	76	#endif
embeddedartists	0:c828045bbe69	77	/ability to convert error numerical codes to English text string/
embeddedartists	0:c828045bbe69	78	#ifndef LODEPNG_NO_COMPILE_ERROR_TEXT
embeddedartists	0:c828045bbe69	79	#define LODEPNG_COMPILE_ERROR_TEXT
embeddedartists	0:c828045bbe69	80	#endif
embeddedartists	0:c828045bbe69	81	/*Compile the default allocators (C's free, malloc and realloc). If you disable this,
embeddedartists	0:c828045bbe69	82	you can define the functions lodepng_free, lodepng_malloc and lodepng_realloc in your
embeddedartists	0:c828045bbe69	83	source files with custom allocators.*/
embeddedartists	0:c828045bbe69	84	#ifndef LODEPNG_NO_COMPILE_ALLOCATORS
embeddedartists	0:c828045bbe69	85	#define LODEPNG_COMPILE_ALLOCATORS
embeddedartists	0:c828045bbe69	86	#endif
embeddedartists	0:c828045bbe69	87	/compile the C++ version (you can disable the C++ wrapper here even when compiling for C++)/
embeddedartists	0:c828045bbe69	88	#ifdef __cplusplus
embeddedartists	0:c828045bbe69	89	#ifndef LODEPNG_NO_COMPILE_CPP
embeddedartists	0:c828045bbe69	90	#define LODEPNG_COMPILE_CPP
embeddedartists	0:c828045bbe69	91	#endif
embeddedartists	0:c828045bbe69	92	#endif
embeddedartists	0:c828045bbe69	93
embeddedartists	0:c828045bbe69	94	#ifdef LODEPNG_COMPILE_PNG
embeddedartists	0:c828045bbe69	95	/The PNG color types (also used for raw)./
embeddedartists	0:c828045bbe69	96	typedef enum LodePNGColorType
embeddedartists	0:c828045bbe69	97	{
embeddedartists	0:c828045bbe69	98	LCT_GREY = 0, /greyscale: 1,2,4,8,16 bit/
embeddedartists	0:c828045bbe69	99	LCT_RGB = 2, /RGB: 8,16 bit/
embeddedartists	0:c828045bbe69	100	LCT_PALETTE = 3, /palette: 1,2,4,8 bit/
embeddedartists	0:c828045bbe69	101	LCT_GREY_ALPHA = 4, /greyscale with alpha: 8,16 bit/
embeddedartists	0:c828045bbe69	102	LCT_RGBA = 6 /RGB with alpha: 8,16 bit/
embeddedartists	0:c828045bbe69	103	} LodePNGColorType;
embeddedartists	0:c828045bbe69	104
embeddedartists	0:c828045bbe69	105	#ifdef LODEPNG_COMPILE_DECODER
embeddedartists	0:c828045bbe69	106	/*
embeddedartists	0:c828045bbe69	107	Converts PNG data in memory to raw pixel data.
embeddedartists	0:c828045bbe69	108	out: Output parameter. Pointer to buffer that will contain the raw pixel data.
embeddedartists	0:c828045bbe69	109	After decoding, its size is w * h * (bytes per pixel) bytes larger than
embeddedartists	0:c828045bbe69	110	initially. Bytes per pixel depends on colortype and bitdepth.
embeddedartists	0:c828045bbe69	111	Must be freed after usage with free(*out).
embeddedartists	0:c828045bbe69	112	Note: for 16-bit per channel colors, uses big endian format like PNG does.
embeddedartists	0:c828045bbe69	113	w: Output parameter. Pointer to width of pixel data.
embeddedartists	0:c828045bbe69	114	h: Output parameter. Pointer to height of pixel data.
embeddedartists	0:c828045bbe69	115	in: Memory buffer with the PNG file.
embeddedartists	0:c828045bbe69	116	insize: size of the in buffer.
embeddedartists	0:c828045bbe69	117	colortype: the desired color type for the raw output image. See explanation on PNG color types.
embeddedartists	0:c828045bbe69	118	bitdepth: the desired bit depth for the raw output image. See explanation on PNG color types.
embeddedartists	0:c828045bbe69	119	Return value: LodePNG error code (0 means no error).
embeddedartists	0:c828045bbe69	120	*/
embeddedartists	0:c828045bbe69	121	unsigned lodepng_decode_memory(unsigned char** out, unsigned* w, unsigned* h,
embeddedartists	0:c828045bbe69	122	const unsigned char* in, size_t insize,
embeddedartists	0:c828045bbe69	123	LodePNGColorType colortype, unsigned bitdepth);
embeddedartists	0:c828045bbe69	124
embeddedartists	0:c828045bbe69	125	/Same as lodepng_decode_memory, but always decodes to 32-bit RGBA raw image/
embeddedartists	0:c828045bbe69	126	unsigned lodepng_decode32(unsigned char** out, unsigned* w, unsigned* h,
embeddedartists	0:c828045bbe69	127	const unsigned char* in, size_t insize);
embeddedartists	0:c828045bbe69	128
embeddedartists	0:c828045bbe69	129	/Same as lodepng_decode_memory, but always decodes to 24-bit RGB raw image/
embeddedartists	0:c828045bbe69	130	unsigned lodepng_decode24(unsigned char** out, unsigned* w, unsigned* h,
embeddedartists	0:c828045bbe69	131	const unsigned char* in, size_t insize);
embeddedartists	0:c828045bbe69	132
embeddedartists	0:c828045bbe69	133	#ifdef LODEPNG_COMPILE_DISK
embeddedartists	0:c828045bbe69	134	/*
embeddedartists	0:c828045bbe69	135	Load PNG from disk, from file with given name.
embeddedartists	0:c828045bbe69	136	Same as the other decode functions, but instead takes a filename as input.
embeddedartists	0:c828045bbe69	137	*/
embeddedartists	0:c828045bbe69	138	unsigned lodepng_decode_file(unsigned char** out, unsigned* w, unsigned* h,
embeddedartists	0:c828045bbe69	139	const char* filename,
embeddedartists	0:c828045bbe69	140	LodePNGColorType colortype, unsigned bitdepth);
embeddedartists	0:c828045bbe69	141
embeddedartists	0:c828045bbe69	142	/Same as lodepng_decode_file, but always decodes to 32-bit RGBA raw image./
embeddedartists	0:c828045bbe69	143	unsigned lodepng_decode32_file(unsigned char** out, unsigned* w, unsigned* h,
embeddedartists	0:c828045bbe69	144	const char* filename);
embeddedartists	0:c828045bbe69	145
embeddedartists	0:c828045bbe69	146	/Same as lodepng_decode_file, but always decodes to 24-bit RGB raw image./
embeddedartists	0:c828045bbe69	147	unsigned lodepng_decode24_file(unsigned char** out, unsigned* w, unsigned* h,
embeddedartists	0:c828045bbe69	148	const char* filename);
embeddedartists	0:c828045bbe69	149	#endif /LODEPNG_COMPILE_DISK/
embeddedartists	0:c828045bbe69	150	#endif /LODEPNG_COMPILE_DECODER/
embeddedartists	0:c828045bbe69	151
embeddedartists	0:c828045bbe69	152
embeddedartists	0:c828045bbe69	153	#ifdef LODEPNG_COMPILE_ENCODER
embeddedartists	0:c828045bbe69	154	/*
embeddedartists	0:c828045bbe69	155	Converts raw pixel data into a PNG image in memory. The colortype and bitdepth
embeddedartists	0:c828045bbe69	156	of the output PNG image cannot be chosen, they are automatically determined
embeddedartists	0:c828045bbe69	157	by the colortype, bitdepth and content of the input pixel data.
embeddedartists	0:c828045bbe69	158	Note: for 16-bit per channel colors, needs big endian format like PNG does.
embeddedartists	0:c828045bbe69	159	out: Output parameter. Pointer to buffer that will contain the PNG image data.
embeddedartists	0:c828045bbe69	160	Must be freed after usage with free(*out).
embeddedartists	0:c828045bbe69	161	outsize: Output parameter. Pointer to the size in bytes of the out buffer.
embeddedartists	0:c828045bbe69	162	image: The raw pixel data to encode. The size of this buffer should be
embeddedartists	0:c828045bbe69	163	w * h * (bytes per pixel), bytes per pixel depends on colortype and bitdepth.
embeddedartists	0:c828045bbe69	164	w: width of the raw pixel data in pixels.
embeddedartists	0:c828045bbe69	165	h: height of the raw pixel data in pixels.
embeddedartists	0:c828045bbe69	166	colortype: the color type of the raw input image. See explanation on PNG color types.
embeddedartists	0:c828045bbe69	167	bitdepth: the bit depth of the raw input image. See explanation on PNG color types.
embeddedartists	0:c828045bbe69	168	Return value: LodePNG error code (0 means no error).
embeddedartists	0:c828045bbe69	169	*/
embeddedartists	0:c828045bbe69	170	unsigned lodepng_encode_memory(unsigned char** out, size_t* outsize,
embeddedartists	0:c828045bbe69	171	const unsigned char* image, unsigned w, unsigned h,
embeddedartists	0:c828045bbe69	172	LodePNGColorType colortype, unsigned bitdepth);
embeddedartists	0:c828045bbe69	173
embeddedartists	0:c828045bbe69	174	/Same as lodepng_encode_memory, but always encodes from 32-bit RGBA raw image./
embeddedartists	0:c828045bbe69	175	unsigned lodepng_encode32(unsigned char** out, size_t* outsize,
embeddedartists	0:c828045bbe69	176	const unsigned char* image, unsigned w, unsigned h);
embeddedartists	0:c828045bbe69	177
embeddedartists	0:c828045bbe69	178	/Same as lodepng_encode_memory, but always encodes from 24-bit RGB raw image./
embeddedartists	0:c828045bbe69	179	unsigned lodepng_encode24(unsigned char** out, size_t* outsize,
embeddedartists	0:c828045bbe69	180	const unsigned char* image, unsigned w, unsigned h);
embeddedartists	0:c828045bbe69	181
embeddedartists	0:c828045bbe69	182	#ifdef LODEPNG_COMPILE_DISK
embeddedartists	0:c828045bbe69	183	/*
embeddedartists	0:c828045bbe69	184	Converts raw pixel data into a PNG file on disk.
embeddedartists	0:c828045bbe69	185	Same as the other encode functions, but instead takes a filename as output.
embeddedartists	0:c828045bbe69	186	NOTE: This overwrites existing files without warning!
embeddedartists	0:c828045bbe69	187	*/
embeddedartists	0:c828045bbe69	188	unsigned lodepng_encode_file(const char* filename,
embeddedartists	0:c828045bbe69	189	const unsigned char* image, unsigned w, unsigned h,
embeddedartists	0:c828045bbe69	190	LodePNGColorType colortype, unsigned bitdepth);
embeddedartists	0:c828045bbe69	191
embeddedartists	0:c828045bbe69	192	/Same as lodepng_encode_file, but always encodes from 32-bit RGBA raw image./
embeddedartists	0:c828045bbe69	193	unsigned lodepng_encode32_file(const char* filename,
embeddedartists	0:c828045bbe69	194	const unsigned char* image, unsigned w, unsigned h);
embeddedartists	0:c828045bbe69	195
embeddedartists	0:c828045bbe69	196	/Same as lodepng_encode_file, but always encodes from 24-bit RGB raw image./
embeddedartists	0:c828045bbe69	197	unsigned lodepng_encode24_file(const char* filename,
embeddedartists	0:c828045bbe69	198	const unsigned char* image, unsigned w, unsigned h);
embeddedartists	0:c828045bbe69	199	#endif /LODEPNG_COMPILE_DISK/
embeddedartists	0:c828045bbe69	200	#endif /LODEPNG_COMPILE_ENCODER/
embeddedartists	0:c828045bbe69	201
embeddedartists	0:c828045bbe69	202
embeddedartists	0:c828045bbe69	203	#ifdef LODEPNG_COMPILE_CPP
embeddedartists	0:c828045bbe69	204	namespace lodepng
embeddedartists	0:c828045bbe69	205	{
embeddedartists	0:c828045bbe69	206	#ifdef LODEPNG_COMPILE_DECODER
embeddedartists	0:c828045bbe69	207	/Same as lodepng_decode_memory, but decodes to an std::vector./
embeddedartists	0:c828045bbe69	208	unsigned decode(std::vector<unsigned char>& out, unsigned& w, unsigned& h,
embeddedartists	0:c828045bbe69	209	const unsigned char* in, size_t insize,
embeddedartists	0:c828045bbe69	210	LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8);
embeddedartists	0:c828045bbe69	211	unsigned decode(std::vector<unsigned char>& out, unsigned& w, unsigned& h,
embeddedartists	0:c828045bbe69	212	const std::vector<unsigned char>& in,
embeddedartists	0:c828045bbe69	213	LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8);
embeddedartists	0:c828045bbe69	214	#ifdef LODEPNG_COMPILE_DISK
embeddedartists	0:c828045bbe69	215	/*
embeddedartists	0:c828045bbe69	216	Converts PNG file from disk to raw pixel data in memory.
embeddedartists	0:c828045bbe69	217	Same as the other decode functions, but instead takes a filename as input.
embeddedartists	0:c828045bbe69	218	*/
embeddedartists	0:c828045bbe69	219	unsigned decode(std::vector<unsigned char>& out, unsigned& w, unsigned& h,
embeddedartists	0:c828045bbe69	220	const std::string& filename,
embeddedartists	0:c828045bbe69	221	LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8);
embeddedartists	0:c828045bbe69	222	#endif //LODEPNG_COMPILE_DISK
embeddedartists	0:c828045bbe69	223	#endif //LODEPNG_COMPILE_DECODER
embeddedartists	0:c828045bbe69	224
embeddedartists	0:c828045bbe69	225	#ifdef LODEPNG_COMPILE_ENCODER
embeddedartists	0:c828045bbe69	226	/Same as lodepng_encode_memory, but encodes to an std::vector./
embeddedartists	0:c828045bbe69	227	unsigned encode(std::vector<unsigned char>& out,
embeddedartists	0:c828045bbe69	228	const unsigned char* in, unsigned w, unsigned h,
embeddedartists	0:c828045bbe69	229	LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8);
embeddedartists	0:c828045bbe69	230	unsigned encode(std::vector<unsigned char>& out,
embeddedartists	0:c828045bbe69	231	const std::vector<unsigned char>& in, unsigned w, unsigned h,
embeddedartists	0:c828045bbe69	232	LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8);
embeddedartists	0:c828045bbe69	233	#ifdef LODEPNG_COMPILE_DISK
embeddedartists	0:c828045bbe69	234	/*
embeddedartists	0:c828045bbe69	235	Converts 32-bit RGBA raw pixel data into a PNG file on disk.
embeddedartists	0:c828045bbe69	236	Same as the other encode functions, but instead takes a filename as output.
embeddedartists	0:c828045bbe69	237	NOTE: This overwrites existing files without warning!
embeddedartists	0:c828045bbe69	238	*/
embeddedartists	0:c828045bbe69	239	unsigned encode(const std::string& filename,
embeddedartists	0:c828045bbe69	240	const unsigned char* in, unsigned w, unsigned h,
embeddedartists	0:c828045bbe69	241	LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8);
embeddedartists	0:c828045bbe69	242	unsigned encode(const std::string& filename,
embeddedartists	0:c828045bbe69	243	const std::vector<unsigned char>& in, unsigned w, unsigned h,
embeddedartists	0:c828045bbe69	244	LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8);
embeddedartists	0:c828045bbe69	245	#endif //LODEPNG_COMPILE_DISK
embeddedartists	0:c828045bbe69	246	#endif //LODEPNG_COMPILE_ENCODER
embeddedartists	0:c828045bbe69	247	} //namespace lodepng
embeddedartists	0:c828045bbe69	248	#endif /LODEPNG_COMPILE_CPP/
embeddedartists	0:c828045bbe69	249	#endif /LODEPNG_COMPILE_PNG/
embeddedartists	0:c828045bbe69	250
embeddedartists	0:c828045bbe69	251	#ifdef LODEPNG_COMPILE_ERROR_TEXT
embeddedartists	0:c828045bbe69	252	/Returns an English description of the numerical error code./
embeddedartists	0:c828045bbe69	253	const char* lodepng_error_text(unsigned code);
embeddedartists	0:c828045bbe69	254	#endif /LODEPNG_COMPILE_ERROR_TEXT/
embeddedartists	0:c828045bbe69	255
embeddedartists	0:c828045bbe69	256	#ifdef LODEPNG_COMPILE_DECODER
embeddedartists	0:c828045bbe69	257	/Settings for zlib decompression/
embeddedartists	0:c828045bbe69	258	typedef struct LodePNGDecompressSettings LodePNGDecompressSettings;
embeddedartists	0:c828045bbe69	259	struct LodePNGDecompressSettings
embeddedartists	0:c828045bbe69	260	{
embeddedartists	0:c828045bbe69	261	unsigned ignore_adler32; /if 1, continue and don't give an error message if the Adler32 checksum is corrupted/
embeddedartists	0:c828045bbe69	262
embeddedartists	0:c828045bbe69	263	/use custom zlib decoder instead of built in one (default: null)/
embeddedartists	0:c828045bbe69	264	unsigned (custom_zlib)(unsigned char, size_t,
embeddedartists	0:c828045bbe69	265	const unsigned char*, size_t,
embeddedartists	0:c828045bbe69	266	const LodePNGDecompressSettings*);
embeddedartists	0:c828045bbe69	267	/*use custom deflate decoder instead of built in one (default: null)
embeddedartists	0:c828045bbe69	268	if custom_zlib is used, custom_deflate is ignored since only the built in
embeddedartists	0:c828045bbe69	269	zlib function will call custom_deflate*/
embeddedartists	0:c828045bbe69	270	unsigned (custom_inflate)(unsigned char, size_t,
embeddedartists	0:c828045bbe69	271	const unsigned char*, size_t,
embeddedartists	0:c828045bbe69	272	const LodePNGDecompressSettings*);
embeddedartists	0:c828045bbe69	273
embeddedartists	0:c828045bbe69	274	const void* custom_context; /optional custom settings for custom functions/
embeddedartists	0:c828045bbe69	275	};
embeddedartists	0:c828045bbe69	276
embeddedartists	0:c828045bbe69	277	extern const LodePNGDecompressSettings lodepng_default_decompress_settings;
embeddedartists	0:c828045bbe69	278	void lodepng_decompress_settings_init(LodePNGDecompressSettings* settings);
embeddedartists	0:c828045bbe69	279	#endif /LODEPNG_COMPILE_DECODER/
embeddedartists	0:c828045bbe69	280
embeddedartists	0:c828045bbe69	281	#ifdef LODEPNG_COMPILE_ENCODER
embeddedartists	0:c828045bbe69	282	/*
embeddedartists	0:c828045bbe69	283	Settings for zlib compression. Tweaking these settings tweaks the balance
embeddedartists	0:c828045bbe69	284	between speed and compression ratio.
embeddedartists	0:c828045bbe69	285	*/
embeddedartists	0:c828045bbe69	286	typedef struct LodePNGCompressSettings LodePNGCompressSettings;
embeddedartists	0:c828045bbe69	287	struct LodePNGCompressSettings /deflate = compress/
embeddedartists	0:c828045bbe69	288	{
embeddedartists	0:c828045bbe69	289	/LZ77 related settings/
embeddedartists	0:c828045bbe69	290	unsigned btype; /the block type for LZ (0, 1, 2 or 3, see zlib standard). Should be 2 for proper compression./
embeddedartists	0:c828045bbe69	291	unsigned use_lz77; /whether or not to use LZ77. Should be 1 for proper compression./
embeddedartists	0:c828045bbe69	292	unsigned windowsize; /must be a power of two <= 32768. higher compresses more but is slower. Typical value: 2048./
embeddedartists	0:c828045bbe69	293	unsigned minmatch; /mininum lz77 length. 3 is normally best, 6 can be better for some PNGs. Default: 0/
embeddedartists	0:c828045bbe69	294	unsigned nicematch; /stop searching if >= this length found. Set to 258 for best compression. Default: 128/
embeddedartists	0:c828045bbe69	295	unsigned lazymatching; /use lazy matching: better compression but a bit slower. Default: true/
embeddedartists	0:c828045bbe69	296
embeddedartists	0:c828045bbe69	297	/use custom zlib encoder instead of built in one (default: null)/
embeddedartists	0:c828045bbe69	298	unsigned (custom_zlib)(unsigned char, size_t,
embeddedartists	0:c828045bbe69	299	const unsigned char*, size_t,
embeddedartists	0:c828045bbe69	300	const LodePNGCompressSettings*);
embeddedartists	0:c828045bbe69	301	/*use custom deflate encoder instead of built in one (default: null)
embeddedartists	0:c828045bbe69	302	if custom_zlib is used, custom_deflate is ignored since only the built in
embeddedartists	0:c828045bbe69	303	zlib function will call custom_deflate*/
embeddedartists	0:c828045bbe69	304	unsigned (custom_deflate)(unsigned char, size_t,
embeddedartists	0:c828045bbe69	305	const unsigned char*, size_t,
embeddedartists	0:c828045bbe69	306	const LodePNGCompressSettings*);
embeddedartists	0:c828045bbe69	307
embeddedartists	0:c828045bbe69	308	const void* custom_context; /optional custom settings for custom functions/
embeddedartists	0:c828045bbe69	309	};
embeddedartists	0:c828045bbe69	310
embeddedartists	0:c828045bbe69	311	extern const LodePNGCompressSettings lodepng_default_compress_settings;
embeddedartists	0:c828045bbe69	312	void lodepng_compress_settings_init(LodePNGCompressSettings* settings);
embeddedartists	0:c828045bbe69	313	#endif /LODEPNG_COMPILE_ENCODER/
embeddedartists	0:c828045bbe69	314
embeddedartists	0:c828045bbe69	315	#ifdef LODEPNG_COMPILE_PNG
embeddedartists	0:c828045bbe69	316	/*
embeddedartists	0:c828045bbe69	317	Color mode of an image. Contains all information required to decode the pixel
embeddedartists	0:c828045bbe69	318	bits to RGBA colors. This information is the same as used in the PNG file
embeddedartists	0:c828045bbe69	319	format, and is used both for PNG and raw image data in LodePNG.
embeddedartists	0:c828045bbe69	320	*/
embeddedartists	0:c828045bbe69	321	typedef struct LodePNGColorMode
embeddedartists	0:c828045bbe69	322	{
embeddedartists	0:c828045bbe69	323	/header (IHDR)/
embeddedartists	0:c828045bbe69	324	LodePNGColorType colortype; /color type, see PNG standard or documentation further in this header file/
embeddedartists	0:c828045bbe69	325	unsigned bitdepth; /bits per sample, see PNG standard or documentation further in this header file/
embeddedartists	0:c828045bbe69	326
embeddedartists	0:c828045bbe69	327	/*
embeddedartists	0:c828045bbe69	328	palette (PLTE and tRNS)
embeddedartists	0:c828045bbe69	329
embeddedartists	0:c828045bbe69	330	Dynamically allocated with the colors of the palette, including alpha.
embeddedartists	0:c828045bbe69	331	When encoding a PNG, to store your colors in the palette of the LodePNGColorMode, first use
embeddedartists	0:c828045bbe69	332	lodepng_palette_clear, then for each color use lodepng_palette_add.
embeddedartists	0:c828045bbe69	333	If you encode an image without alpha with palette, don't forget to put value 255 in each A byte of the palette.
embeddedartists	0:c828045bbe69	334
embeddedartists	0:c828045bbe69	335	When decoding, by default you can ignore this palette, since LodePNG already
embeddedartists	0:c828045bbe69	336	fills the palette colors in the pixels of the raw RGBA output.
embeddedartists	0:c828045bbe69	337
embeddedartists	0:c828045bbe69	338	The palette is only supported for color type 3.
embeddedartists	0:c828045bbe69	339	*/
embeddedartists	0:c828045bbe69	340	unsigned char* palette; /palette in RGBARGBA... order. When allocated, must be either 0, or have size 1024/
embeddedartists	0:c828045bbe69	341	size_t palettesize; /palette size in number of colors (amount of bytes is 4 palettesize)*/
embeddedartists	0:c828045bbe69	342
embeddedartists	0:c828045bbe69	343	/*
embeddedartists	0:c828045bbe69	344	transparent color key (tRNS)
embeddedartists	0:c828045bbe69	345
embeddedartists	0:c828045bbe69	346	This color uses the same bit depth as the bitdepth value in this struct, which can be 1-bit to 16-bit.
embeddedartists	0:c828045bbe69	347	For greyscale PNGs, r, g and b will all 3 be set to the same.
embeddedartists	0:c828045bbe69	348
embeddedartists	0:c828045bbe69	349	When decoding, by default you can ignore this information, since LodePNG sets
embeddedartists	0:c828045bbe69	350	pixels with this key to transparent already in the raw RGBA output.
embeddedartists	0:c828045bbe69	351
embeddedartists	0:c828045bbe69	352	The color key is only supported for color types 0 and 2.
embeddedartists	0:c828045bbe69	353	*/
embeddedartists	0:c828045bbe69	354	unsigned key_defined; /is a transparent color key given? 0 = false, 1 = true/
embeddedartists	0:c828045bbe69	355	unsigned key_r; /red/greyscale component of color key/
embeddedartists	0:c828045bbe69	356	unsigned key_g; /green component of color key/
embeddedartists	0:c828045bbe69	357	unsigned key_b; /blue component of color key/
embeddedartists	0:c828045bbe69	358	} LodePNGColorMode;
embeddedartists	0:c828045bbe69	359
embeddedartists	0:c828045bbe69	360	/init, cleanup and copy functions to use with this struct/
embeddedartists	0:c828045bbe69	361	void lodepng_color_mode_init(LodePNGColorMode* info);
embeddedartists	0:c828045bbe69	362	void lodepng_color_mode_cleanup(LodePNGColorMode* info);
embeddedartists	0:c828045bbe69	363	/return value is error code (0 means no error)/
embeddedartists	0:c828045bbe69	364	unsigned lodepng_color_mode_copy(LodePNGColorMode* dest, const LodePNGColorMode* source);
embeddedartists	0:c828045bbe69	365
embeddedartists	0:c828045bbe69	366	void lodepng_palette_clear(LodePNGColorMode* info);
embeddedartists	0:c828045bbe69	367	/add 1 color to the palette/
embeddedartists	0:c828045bbe69	368	unsigned lodepng_palette_add(LodePNGColorMode* info,
embeddedartists	0:c828045bbe69	369	unsigned char r, unsigned char g, unsigned char b, unsigned char a);
embeddedartists	0:c828045bbe69	370
embeddedartists	0:c828045bbe69	371	/get the total amount of bits per pixel, based on colortype and bitdepth in the struct/
embeddedartists	0:c828045bbe69	372	unsigned lodepng_get_bpp(const LodePNGColorMode* info);
embeddedartists	0:c828045bbe69	373	/*get the amount of color channels used, based on colortype in the struct.
embeddedartists	0:c828045bbe69	374	If a palette is used, it counts as 1 channel.*/
embeddedartists	0:c828045bbe69	375	unsigned lodepng_get_channels(const LodePNGColorMode* info);
embeddedartists	0:c828045bbe69	376	/is it a greyscale type? (only colortype 0 or 4)/
embeddedartists	0:c828045bbe69	377	unsigned lodepng_is_greyscale_type(const LodePNGColorMode* info);
embeddedartists	0:c828045bbe69	378	/has it got an alpha channel? (only colortype 2 or 6)/
embeddedartists	0:c828045bbe69	379	unsigned lodepng_is_alpha_type(const LodePNGColorMode* info);
embeddedartists	0:c828045bbe69	380	/has it got a palette? (only colortype 3)/
embeddedartists	0:c828045bbe69	381	unsigned lodepng_is_palette_type(const LodePNGColorMode* info);
embeddedartists	0:c828045bbe69	382	/*only returns true if there is a palette and there is a value in the palette with alpha < 255.
embeddedartists	0:c828045bbe69	383	Loops through the palette to check this.*/
embeddedartists	0:c828045bbe69	384	unsigned lodepng_has_palette_alpha(const LodePNGColorMode* info);
embeddedartists	0:c828045bbe69	385	/*
embeddedartists	0:c828045bbe69	386	Check if the given color info indicates the possibility of having non-opaque pixels in the PNG image.
embeddedartists	0:c828045bbe69	387	Returns true if the image can have translucent or invisible pixels (it still be opaque if it doesn't use such pixels).
embeddedartists	0:c828045bbe69	388	Returns false if the image can only have opaque pixels.
embeddedartists	0:c828045bbe69	389	In detail, it returns true only if it's a color type with alpha, or has a palette with non-opaque values,
embeddedartists	0:c828045bbe69	390	or if "key_defined" is true.
embeddedartists	0:c828045bbe69	391	*/
embeddedartists	0:c828045bbe69	392	unsigned lodepng_can_have_alpha(const LodePNGColorMode* info);
embeddedartists	0:c828045bbe69	393	/Returns the byte size of a raw image buffer with given width, height and color mode/
embeddedartists	0:c828045bbe69	394	size_t lodepng_get_raw_size(unsigned w, unsigned h, const LodePNGColorMode* color);
embeddedartists	0:c828045bbe69	395
embeddedartists	0:c828045bbe69	396	#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS
embeddedartists	0:c828045bbe69	397	/The information of a Time chunk in PNG./
embeddedartists	0:c828045bbe69	398	typedef struct LodePNGTime
embeddedartists	0:c828045bbe69	399	{
embeddedartists	0:c828045bbe69	400	unsigned year; /2 bytes used (0-65535)/
embeddedartists	0:c828045bbe69	401	unsigned month; /1-12/
embeddedartists	0:c828045bbe69	402	unsigned day; /1-31/
embeddedartists	0:c828045bbe69	403	unsigned hour; /0-23/
embeddedartists	0:c828045bbe69	404	unsigned minute; /0-59/
embeddedartists	0:c828045bbe69	405	unsigned second; /0-60 (to allow for leap seconds)/
embeddedartists	0:c828045bbe69	406	} LodePNGTime;
embeddedartists	0:c828045bbe69	407	#endif /LODEPNG_COMPILE_ANCILLARY_CHUNKS/
embeddedartists	0:c828045bbe69	408
embeddedartists	0:c828045bbe69	409	/Information about the PNG image, except pixels, width and height./
embeddedartists	0:c828045bbe69	410	typedef struct LodePNGInfo
embeddedartists	0:c828045bbe69	411	{
embeddedartists	0:c828045bbe69	412	/header (IHDR), palette (PLTE) and transparency (tRNS) chunks/
embeddedartists	0:c828045bbe69	413	unsigned compression_method;/compression method of the original file. Always 0./
embeddedartists	0:c828045bbe69	414	unsigned filter_method; /filter method of the original file/
embeddedartists	0:c828045bbe69	415	unsigned interlace_method; /interlace method of the original file/
embeddedartists	0:c828045bbe69	416	LodePNGColorMode color; /color type and bits, palette and transparency of the PNG file/
embeddedartists	0:c828045bbe69	417
embeddedartists	0:c828045bbe69	418	#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS
embeddedartists	0:c828045bbe69	419	/*
embeddedartists	0:c828045bbe69	420	suggested background color chunk (bKGD)
embeddedartists	0:c828045bbe69	421	This color uses the same color mode as the PNG (except alpha channel), which can be 1-bit to 16-bit.
embeddedartists	0:c828045bbe69	422
embeddedartists	0:c828045bbe69	423	For greyscale PNGs, r, g and b will all 3 be set to the same. When encoding
embeddedartists	0:c828045bbe69	424	the encoder writes the red one. For palette PNGs: When decoding, the RGB value
embeddedartists	0:c828045bbe69	425	will be stored, not a palette index. But when encoding, specify the index of
embeddedartists	0:c828045bbe69	426	the palette in background_r, the other two are then ignored.
embeddedartists	0:c828045bbe69	427
embeddedartists	0:c828045bbe69	428	The decoder does not use this background color to edit the color of pixels.
embeddedartists	0:c828045bbe69	429	*/
embeddedartists	0:c828045bbe69	430	unsigned background_defined; /is a suggested background color given?/
embeddedartists	0:c828045bbe69	431	unsigned background_r; /red component of suggested background color/
embeddedartists	0:c828045bbe69	432	unsigned background_g; /green component of suggested background color/
embeddedartists	0:c828045bbe69	433	unsigned background_b; /blue component of suggested background color/
embeddedartists	0:c828045bbe69	434
embeddedartists	0:c828045bbe69	435	/*
embeddedartists	0:c828045bbe69	436	non-international text chunks (tEXt and zTXt)
embeddedartists	0:c828045bbe69	437
embeddedartists	0:c828045bbe69	438	The char** arrays each contain num strings. The actual messages are in
embeddedartists	0:c828045bbe69	439	text_strings, while text_keys are keywords that give a short description what
embeddedartists	0:c828045bbe69	440	the actual text represents, e.g. Title, Author, Description, or anything else.
embeddedartists	0:c828045bbe69	441
embeddedartists	0:c828045bbe69	442	A keyword is minimum 1 character and maximum 79 characters long. It's
embeddedartists	0:c828045bbe69	443	discouraged to use a single line length longer than 79 characters for texts.
embeddedartists	0:c828045bbe69	444
embeddedartists	0:c828045bbe69	445	Don't allocate these text buffers yourself. Use the init/cleanup functions
embeddedartists	0:c828045bbe69	446	correctly and use lodepng_add_text and lodepng_clear_text.
embeddedartists	0:c828045bbe69	447	*/
embeddedartists	0:c828045bbe69	448	size_t text_num; /the amount of texts in these char* buffers (there may be more texts in itext)*/
embeddedartists	0:c828045bbe69	449	char** text_keys; /the keyword of a text chunk (e.g. "Comment")/
embeddedartists	0:c828045bbe69	450	char** text_strings; /the actual text/
embeddedartists	0:c828045bbe69	451
embeddedartists	0:c828045bbe69	452	/*
embeddedartists	0:c828045bbe69	453	international text chunks (iTXt)
embeddedartists	0:c828045bbe69	454	Similar to the non-international text chunks, but with additional strings
embeddedartists	0:c828045bbe69	455	"langtags" and "transkeys".
embeddedartists	0:c828045bbe69	456	*/
embeddedartists	0:c828045bbe69	457	size_t itext_num; /the amount of international texts in this PNG/
embeddedartists	0:c828045bbe69	458	char** itext_keys; /the English keyword of the text chunk (e.g. "Comment")/
embeddedartists	0:c828045bbe69	459	char** itext_langtags; /language tag for this text's language, ISO/IEC 646 string, e.g. ISO 639 language tag/
embeddedartists	0:c828045bbe69	460	char** itext_transkeys; /keyword translated to the international language - UTF-8 string/
embeddedartists	0:c828045bbe69	461	char** itext_strings; /the actual international text - UTF-8 string/
embeddedartists	0:c828045bbe69	462
embeddedartists	0:c828045bbe69	463	/time chunk (tIME)/
embeddedartists	0:c828045bbe69	464	unsigned time_defined; /set to 1 to make the encoder generate a tIME chunk/
embeddedartists	0:c828045bbe69	465	LodePNGTime time;
embeddedartists	0:c828045bbe69	466
embeddedartists	0:c828045bbe69	467	/phys chunk (pHYs)/
embeddedartists	0:c828045bbe69	468	unsigned phys_defined; /if 0, there is no pHYs chunk and the values below are undefined, if 1 else there is one/
embeddedartists	0:c828045bbe69	469	unsigned phys_x; /pixels per unit in x direction/
embeddedartists	0:c828045bbe69	470	unsigned phys_y; /pixels per unit in y direction/
embeddedartists	0:c828045bbe69	471	unsigned phys_unit; /may be 0 (unknown unit) or 1 (metre)/
embeddedartists	0:c828045bbe69	472
embeddedartists	0:c828045bbe69	473	/*
embeddedartists	0:c828045bbe69	474	unknown chunks
embeddedartists	0:c828045bbe69	475	There are 3 buffers, one for each position in the PNG where unknown chunks can appear
embeddedartists	0:c828045bbe69	476	each buffer contains all unknown chunks for that position consecutively
embeddedartists	0:c828045bbe69	477	The 3 buffers are the unknown chunks between certain critical chunks:
embeddedartists	0:c828045bbe69	478	0: IHDR-PLTE, 1: PLTE-IDAT, 2: IDAT-IEND
embeddedartists	0:c828045bbe69	479	Do not allocate or traverse this data yourself. Use the chunk traversing functions declared
embeddedartists	0:c828045bbe69	480	later, such as lodepng_chunk_next and lodepng_chunk_append, to read/write this struct.
embeddedartists	0:c828045bbe69	481	*/
embeddedartists	0:c828045bbe69	482	unsigned char* unknown_chunks_data[3];
embeddedartists	0:c828045bbe69	483	size_t unknown_chunks_size[3]; /size in bytes of the unknown chunks, given for protection/
embeddedartists	0:c828045bbe69	484	#endif /LODEPNG_COMPILE_ANCILLARY_CHUNKS/
embeddedartists	0:c828045bbe69	485	} LodePNGInfo;
embeddedartists	0:c828045bbe69	486
embeddedartists	0:c828045bbe69	487	/init, cleanup and copy functions to use with this struct/
embeddedartists	0:c828045bbe69	488	void lodepng_info_init(LodePNGInfo* info);
embeddedartists	0:c828045bbe69	489	void lodepng_info_cleanup(LodePNGInfo* info);
embeddedartists	0:c828045bbe69	490	/return value is error code (0 means no error)/
embeddedartists	0:c828045bbe69	491	unsigned lodepng_info_copy(LodePNGInfo* dest, const LodePNGInfo* source);
embeddedartists	0:c828045bbe69	492
embeddedartists	0:c828045bbe69	493	#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS
embeddedartists	0:c828045bbe69	494	void lodepng_clear_text(LodePNGInfo* info); /use this to clear the texts again after you filled them in/
embeddedartists	0:c828045bbe69	495	unsigned lodepng_add_text(LodePNGInfo* info, const char* key, const char* str); /push back both texts at once/
embeddedartists	0:c828045bbe69	496
embeddedartists	0:c828045bbe69	497	void lodepng_clear_itext(LodePNGInfo* info); /use this to clear the itexts again after you filled them in/
embeddedartists	0:c828045bbe69	498	unsigned lodepng_add_itext(LodePNGInfo* info, const char* key, const char* langtag,
embeddedartists	0:c828045bbe69	499	const char* transkey, const char* str); /push back the 4 texts of 1 chunk at once/
embeddedartists	0:c828045bbe69	500	#endif /LODEPNG_COMPILE_ANCILLARY_CHUNKS/
embeddedartists	0:c828045bbe69	501
embeddedartists	0:c828045bbe69	502	/*
embeddedartists	0:c828045bbe69	503	Converts raw buffer from one color type to another color type, based on
embeddedartists	0:c828045bbe69	504	LodePNGColorMode structs to describe the input and output color type.
embeddedartists	0:c828045bbe69	505	See the reference manual at the end of this header file to see which color conversions are supported.
embeddedartists	0:c828045bbe69	506	return value = LodePNG error code (0 if all went ok, an error if the conversion isn't supported)
embeddedartists	0:c828045bbe69	507	The out buffer must have size (w * h * bpp + 7) / 8, where bpp is the bits per pixel
embeddedartists	0:c828045bbe69	508	of the output color type (lodepng_get_bpp)
embeddedartists	0:c828045bbe69	509	The fix_png value works as described in struct LodePNGDecoderSettings.
embeddedartists	0:c828045bbe69	510	Note: for 16-bit per channel colors, uses big endian format like PNG does.
embeddedartists	0:c828045bbe69	511	*/
embeddedartists	0:c828045bbe69	512	unsigned lodepng_convert(unsigned char* out, const unsigned char* in,
embeddedartists	0:c828045bbe69	513	LodePNGColorMode* mode_out, const LodePNGColorMode* mode_in,
embeddedartists	0:c828045bbe69	514	unsigned w, unsigned h, unsigned fix_png);
embeddedartists	0:c828045bbe69	515
embeddedartists	0:c828045bbe69	516	#ifdef LODEPNG_COMPILE_DECODER
embeddedartists	0:c828045bbe69	517	/*
embeddedartists	0:c828045bbe69	518	Settings for the decoder. This contains settings for the PNG and the Zlib
embeddedartists	0:c828045bbe69	519	decoder, but not the Info settings from the Info structs.
embeddedartists	0:c828045bbe69	520	*/
embeddedartists	0:c828045bbe69	521	typedef struct LodePNGDecoderSettings
embeddedartists	0:c828045bbe69	522	{
embeddedartists	0:c828045bbe69	523	LodePNGDecompressSettings zlibsettings; /in here is the setting to ignore Adler32 checksums/
embeddedartists	0:c828045bbe69	524
embeddedartists	0:c828045bbe69	525	unsigned ignore_crc; /ignore CRC checksums/
embeddedartists	0:c828045bbe69	526	/*
embeddedartists	0:c828045bbe69	527	The fix_png setting, if 1, makes the decoder tolerant towards some PNG images
embeddedartists	0:c828045bbe69	528	that do not correctly follow the PNG specification. This only supports errors
embeddedartists	0:c828045bbe69	529	that are fixable, were found in images that are actually used on the web, and
embeddedartists	0:c828045bbe69	530	are silently tolerated by other decoders as well. Currently only one such fix
embeddedartists	0:c828045bbe69	531	is implemented: if a palette index is out of bounds given the palette size,
embeddedartists	0:c828045bbe69	532	interpret it as opaque black.
embeddedartists	0:c828045bbe69	533	By default this value is 0, which makes it stop with an error on such images.
embeddedartists	0:c828045bbe69	534	*/
embeddedartists	0:c828045bbe69	535	unsigned fix_png;
embeddedartists	0:c828045bbe69	536	unsigned color_convert; /whether to convert the PNG to the color type you want. Default: yes/
embeddedartists	0:c828045bbe69	537
embeddedartists	0:c828045bbe69	538	#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS
embeddedartists	0:c828045bbe69	539	unsigned read_text_chunks; /if false but remember_unknown_chunks is true, they're stored in the unknown chunks/
embeddedartists	0:c828045bbe69	540	/store all bytes from unknown chunks in the LodePNGInfo (off by default, useful for a png editor)/
embeddedartists	0:c828045bbe69	541	unsigned remember_unknown_chunks;
embeddedartists	0:c828045bbe69	542	#endif /LODEPNG_COMPILE_ANCILLARY_CHUNKS/
embeddedartists	0:c828045bbe69	543	} LodePNGDecoderSettings;
embeddedartists	0:c828045bbe69	544
embeddedartists	0:c828045bbe69	545	void lodepng_decoder_settings_init(LodePNGDecoderSettings* settings);
embeddedartists	0:c828045bbe69	546	#endif /LODEPNG_COMPILE_DECODER/
embeddedartists	0:c828045bbe69	547
embeddedartists	0:c828045bbe69	548	#ifdef LODEPNG_COMPILE_ENCODER
embeddedartists	0:c828045bbe69	549	/automatically use color type with less bits per pixel if losslessly possible. Default: AUTO/
embeddedartists	0:c828045bbe69	550	typedef enum LodePNGFilterStrategy
embeddedartists	0:c828045bbe69	551	{
embeddedartists	0:c828045bbe69	552	/every filter at zero/
embeddedartists	0:c828045bbe69	553	LFS_ZERO,
embeddedartists	0:c828045bbe69	554	/Use filter that gives minumum sum, as described in the official PNG filter heuristic./
embeddedartists	0:c828045bbe69	555	LFS_MINSUM,
embeddedartists	0:c828045bbe69	556	/*Use the filter type that gives smallest Shannon entropy for this scanline. Depending
embeddedartists	0:c828045bbe69	557	on the image, this is better or worse than minsum.*/
embeddedartists	0:c828045bbe69	558	LFS_ENTROPY,
embeddedartists	0:c828045bbe69	559	/*
embeddedartists	0:c828045bbe69	560	Brute-force-search PNG filters by compressing each filter for each scanline.
embeddedartists	0:c828045bbe69	561	Experimental, very slow, and only rarely gives better compression than MINSUM.
embeddedartists	0:c828045bbe69	562	*/
embeddedartists	0:c828045bbe69	563	LFS_BRUTE_FORCE,
embeddedartists	0:c828045bbe69	564	/use predefined_filters buffer: you specify the filter type for each scanline/
embeddedartists	0:c828045bbe69	565	LFS_PREDEFINED
embeddedartists	0:c828045bbe69	566	} LodePNGFilterStrategy;
embeddedartists	0:c828045bbe69	567
embeddedartists	0:c828045bbe69	568	/automatically use color type with less bits per pixel if losslessly possible. Default: LAC_AUTO/
embeddedartists	0:c828045bbe69	569	typedef enum LodePNGAutoConvert
embeddedartists	0:c828045bbe69	570	{
embeddedartists	0:c828045bbe69	571	LAC_NO, /use color type user requested/
embeddedartists	0:c828045bbe69	572	LAC_ALPHA, /use color type user requested, but if only opaque pixels and RGBA or grey+alpha, use RGB or grey/
embeddedartists	0:c828045bbe69	573	LAC_AUTO, /use PNG color type that can losslessly represent the uncompressed image the smallest possible/
embeddedartists	0:c828045bbe69	574	/*
embeddedartists	0:c828045bbe69	575	like AUTO, but do not choose 1, 2 or 4 bit per pixel types.
embeddedartists	0:c828045bbe69	576	sometimes a PNG image compresses worse if less than 8 bits per pixels.
embeddedartists	0:c828045bbe69	577	*/
embeddedartists	0:c828045bbe69	578	LAC_AUTO_NO_NIBBLES,
embeddedartists	0:c828045bbe69	579	/*
embeddedartists	0:c828045bbe69	580	like AUTO, but never choose palette color type. For small images, encoding
embeddedartists	0:c828045bbe69	581	the palette may take more bytes than what is gained. Note that AUTO also
embeddedartists	0:c828045bbe69	582	already prevents encoding the palette for extremely small images, but that may
embeddedartists	0:c828045bbe69	583	not be sufficient because due to the compression it cannot predict when to
embeddedartists	0:c828045bbe69	584	switch.
embeddedartists	0:c828045bbe69	585	*/
embeddedartists	0:c828045bbe69	586	LAC_AUTO_NO_PALETTE,
embeddedartists	0:c828045bbe69	587	LAC_AUTO_NO_NIBBLES_NO_PALETTE
embeddedartists	0:c828045bbe69	588	} LodePNGAutoConvert;
embeddedartists	0:c828045bbe69	589
embeddedartists	0:c828045bbe69	590
embeddedartists	0:c828045bbe69	591	/*
embeddedartists	0:c828045bbe69	592	Automatically chooses color type that gives smallest amount of bits in the
embeddedartists	0:c828045bbe69	593	output image, e.g. grey if there are only greyscale pixels, palette if there
embeddedartists	0:c828045bbe69	594	are less than 256 colors, ...
embeddedartists	0:c828045bbe69	595	The auto_convert parameter allows limiting it to not use palette, ...
embeddedartists	0:c828045bbe69	596	*/
embeddedartists	0:c828045bbe69	597	unsigned lodepng_auto_choose_color(LodePNGColorMode* mode_out,
embeddedartists	0:c828045bbe69	598	const unsigned char* image, unsigned w, unsigned h,
embeddedartists	0:c828045bbe69	599	const LodePNGColorMode* mode_in,
embeddedartists	0:c828045bbe69	600	LodePNGAutoConvert auto_convert);
embeddedartists	0:c828045bbe69	601
embeddedartists	0:c828045bbe69	602	/Settings for the encoder./
embeddedartists	0:c828045bbe69	603	typedef struct LodePNGEncoderSettings
embeddedartists	0:c828045bbe69	604	{
embeddedartists	0:c828045bbe69	605	LodePNGCompressSettings zlibsettings; /settings for the zlib encoder, such as window size, .../
embeddedartists	0:c828045bbe69	606
embeddedartists	0:c828045bbe69	607	LodePNGAutoConvert auto_convert; /how to automatically choose output PNG color type, if at all/
embeddedartists	0:c828045bbe69	608
embeddedartists	0:c828045bbe69	609	/*If true, follows the official PNG heuristic: if the PNG uses a palette or lower than
embeddedartists	0:c828045bbe69	610	8 bit depth, set all filters to zero. Otherwise use the filter_strategy. Note that to
embeddedartists	0:c828045bbe69	611	completely follow the official PNG heuristic, filter_palette_zero must be true and
embeddedartists	0:c828045bbe69	612	filter_strategy must be LFS_MINSUM*/
embeddedartists	0:c828045bbe69	613	unsigned filter_palette_zero;
embeddedartists	0:c828045bbe69	614	/*Which filter strategy to use when not using zeroes due to filter_palette_zero.
embeddedartists	0:c828045bbe69	615	Set filter_palette_zero to 0 to ensure always using your chosen strategy. Default: LFS_MINSUM*/
embeddedartists	0:c828045bbe69	616	LodePNGFilterStrategy filter_strategy;
embeddedartists	0:c828045bbe69	617	/*used if filter_strategy is LFS_PREDEFINED. In that case, this must point to a buffer with
embeddedartists	0:c828045bbe69	618	the same length as the amount of scanlines in the image, and each value must <= 5. You
embeddedartists	0:c828045bbe69	619	have to cleanup this buffer, LodePNG will never free it. Don't forget that filter_palette_zero
embeddedartists	0:c828045bbe69	620	must be set to 0 to ensure this is also used on palette or low bitdepth images.*/
embeddedartists	0:c828045bbe69	621	const unsigned char* predefined_filters;
embeddedartists	0:c828045bbe69	622
embeddedartists	0:c828045bbe69	623	/*force creating a PLTE chunk if colortype is 2 or 6 (= a suggested palette).
embeddedartists	0:c828045bbe69	624	If colortype is 3, PLTE is _always_ created.*/
embeddedartists	0:c828045bbe69	625	unsigned force_palette;
embeddedartists	0:c828045bbe69	626	#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS
embeddedartists	0:c828045bbe69	627	/add LodePNG identifier and version as a text chunk, for debugging/
embeddedartists	0:c828045bbe69	628	unsigned add_id;
embeddedartists	0:c828045bbe69	629	/encode text chunks as zTXt chunks instead of tEXt chunks, and use compression in iTXt chunks/
embeddedartists	0:c828045bbe69	630	unsigned text_compression;
embeddedartists	0:c828045bbe69	631	#endif /LODEPNG_COMPILE_ANCILLARY_CHUNKS/
embeddedartists	0:c828045bbe69	632	} LodePNGEncoderSettings;
embeddedartists	0:c828045bbe69	633
embeddedartists	0:c828045bbe69	634	void lodepng_encoder_settings_init(LodePNGEncoderSettings* settings);
embeddedartists	0:c828045bbe69	635	#endif /LODEPNG_COMPILE_ENCODER/
embeddedartists	0:c828045bbe69	636
embeddedartists	0:c828045bbe69	637
embeddedartists	0:c828045bbe69	638	#if defined(LODEPNG_COMPILE_DECODER) \|\| defined(LODEPNG_COMPILE_ENCODER)
embeddedartists	0:c828045bbe69	639	/The settings, state and information for extended encoding and decoding./
embeddedartists	0:c828045bbe69	640	typedef struct LodePNGState
embeddedartists	0:c828045bbe69	641	{
embeddedartists	0:c828045bbe69	642	#ifdef LODEPNG_COMPILE_DECODER
embeddedartists	0:c828045bbe69	643	LodePNGDecoderSettings decoder; /the decoding settings/
embeddedartists	0:c828045bbe69	644	#endif /LODEPNG_COMPILE_DECODER/
embeddedartists	0:c828045bbe69	645	#ifdef LODEPNG_COMPILE_ENCODER
embeddedartists	0:c828045bbe69	646	LodePNGEncoderSettings encoder; /the encoding settings/
embeddedartists	0:c828045bbe69	647	#endif /LODEPNG_COMPILE_ENCODER/
embeddedartists	0:c828045bbe69	648	LodePNGColorMode info_raw; /specifies the format in which you would like to get the raw pixel buffer/
embeddedartists	0:c828045bbe69	649	LodePNGInfo info_png; /info of the PNG image obtained after decoding/
embeddedartists	0:c828045bbe69	650	unsigned error;
embeddedartists	0:c828045bbe69	651	#ifdef LODEPNG_COMPILE_CPP
embeddedartists	0:c828045bbe69	652	//For the lodepng::State subclass.
embeddedartists	0:c828045bbe69	653	virtual ~LodePNGState(){}
embeddedartists	0:c828045bbe69	654	#endif
embeddedartists	0:c828045bbe69	655	} LodePNGState;
embeddedartists	0:c828045bbe69	656
embeddedartists	0:c828045bbe69	657	/init, cleanup and copy functions to use with this struct/
embeddedartists	0:c828045bbe69	658	void lodepng_state_init(LodePNGState* state);
embeddedartists	0:c828045bbe69	659	void lodepng_state_cleanup(LodePNGState* state);
embeddedartists	0:c828045bbe69	660	void lodepng_state_copy(LodePNGState* dest, const LodePNGState* source);
embeddedartists	0:c828045bbe69	661	#endif /* defined(LODEPNG_COMPILE_DECODER) \|\| defined(LODEPNG_COMPILE_ENCODER) */
embeddedartists	0:c828045bbe69	662
embeddedartists	0:c828045bbe69	663	#ifdef LODEPNG_COMPILE_DECODER
embeddedartists	0:c828045bbe69	664	/*
embeddedartists	0:c828045bbe69	665	Same as lodepng_decode_memory, but uses a LodePNGState to allow custom settings and
embeddedartists	0:c828045bbe69	666	getting much more information about the PNG image and color mode.
embeddedartists	0:c828045bbe69	667	*/
embeddedartists	0:c828045bbe69	668	unsigned lodepng_decode(unsigned char** out, unsigned* w, unsigned* h,
embeddedartists	0:c828045bbe69	669	LodePNGState* state,
embeddedartists	0:c828045bbe69	670	const unsigned char* in, size_t insize);
embeddedartists	0:c828045bbe69	671
embeddedartists	0:c828045bbe69	672	/*
embeddedartists	0:c828045bbe69	673	Read the PNG header, but not the actual data. This returns only the information
embeddedartists	0:c828045bbe69	674	that is in the header chunk of the PNG, such as width, height and color type. The
embeddedartists	0:c828045bbe69	675	information is placed in the info_png field of the LodePNGState.
embeddedartists	0:c828045bbe69	676	*/
embeddedartists	0:c828045bbe69	677	unsigned lodepng_inspect(unsigned* w, unsigned* h,
embeddedartists	0:c828045bbe69	678	LodePNGState* state,
embeddedartists	0:c828045bbe69	679	const unsigned char* in, size_t insize);
embeddedartists	0:c828045bbe69	680	#endif /LODEPNG_COMPILE_DECODER/
embeddedartists	0:c828045bbe69	681
embeddedartists	0:c828045bbe69	682
embeddedartists	0:c828045bbe69	683	#ifdef LODEPNG_COMPILE_ENCODER
embeddedartists	0:c828045bbe69	684	/This function allocates the out buffer with standard malloc and stores the size in outsize.*/
embeddedartists	0:c828045bbe69	685	unsigned lodepng_encode(unsigned char** out, size_t* outsize,
embeddedartists	0:c828045bbe69	686	const unsigned char* image, unsigned w, unsigned h,
embeddedartists	0:c828045bbe69	687	LodePNGState* state);
embeddedartists	0:c828045bbe69	688	#endif /LODEPNG_COMPILE_ENCODER/
embeddedartists	0:c828045bbe69	689
embeddedartists	0:c828045bbe69	690	/*
embeddedartists	0:c828045bbe69	691	The lodepng_chunk functions are normally not needed, except to traverse the
embeddedartists	0:c828045bbe69	692	unknown chunks stored in the LodePNGInfo struct, or add new ones to it.
embeddedartists	0:c828045bbe69	693	It also allows traversing the chunks of an encoded PNG file yourself.
embeddedartists	0:c828045bbe69	694
embeddedartists	0:c828045bbe69	695	PNG standard chunk naming conventions:
embeddedartists	0:c828045bbe69	696	First byte: uppercase = critical, lowercase = ancillary
embeddedartists	0:c828045bbe69	697	Second byte: uppercase = public, lowercase = private
embeddedartists	0:c828045bbe69	698	Third byte: must be uppercase
embeddedartists	0:c828045bbe69	699	Fourth byte: uppercase = unsafe to copy, lowercase = safe to copy
embeddedartists	0:c828045bbe69	700	*/
embeddedartists	0:c828045bbe69	701
embeddedartists	0:c828045bbe69	702	/get the length of the data of the chunk. Total chunk length has 12 bytes more./
embeddedartists	0:c828045bbe69	703	unsigned lodepng_chunk_length(const unsigned char* chunk);
embeddedartists	0:c828045bbe69	704
embeddedartists	0:c828045bbe69	705	/puts the 4-byte type in null terminated string/
embeddedartists	0:c828045bbe69	706	void lodepng_chunk_type(char type[5], const unsigned char* chunk);
embeddedartists	0:c828045bbe69	707
embeddedartists	0:c828045bbe69	708	/check if the type is the given type/
embeddedartists	0:c828045bbe69	709	unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type);
embeddedartists	0:c828045bbe69	710
embeddedartists	0:c828045bbe69	711	/0: it's one of the critical chunk types, 1: it's an ancillary chunk (see PNG standard)/
embeddedartists	0:c828045bbe69	712	unsigned char lodepng_chunk_ancillary(const unsigned char* chunk);
embeddedartists	0:c828045bbe69	713
embeddedartists	0:c828045bbe69	714	/0: public, 1: private (see PNG standard)/
embeddedartists	0:c828045bbe69	715	unsigned char lodepng_chunk_private(const unsigned char* chunk);
embeddedartists	0:c828045bbe69	716
embeddedartists	0:c828045bbe69	717	/0: the chunk is unsafe to copy, 1: the chunk is safe to copy (see PNG standard)/
embeddedartists	0:c828045bbe69	718	unsigned char lodepng_chunk_safetocopy(const unsigned char* chunk);
embeddedartists	0:c828045bbe69	719
embeddedartists	0:c828045bbe69	720	/get pointer to the data of the chunk, where the input points to the header of the chunk/
embeddedartists	0:c828045bbe69	721	unsigned char* lodepng_chunk_data(unsigned char* chunk);
embeddedartists	0:c828045bbe69	722	const unsigned char* lodepng_chunk_data_const(const unsigned char* chunk);
embeddedartists	0:c828045bbe69	723
embeddedartists	0:c828045bbe69	724	/returns 0 if the crc is correct, 1 if it's incorrect (0 for OK as usual!)/
embeddedartists	0:c828045bbe69	725	unsigned lodepng_chunk_check_crc(const unsigned char* chunk);
embeddedartists	0:c828045bbe69	726
embeddedartists	0:c828045bbe69	727	/generates the correct CRC from the data and puts it in the last 4 bytes of the chunk/
embeddedartists	0:c828045bbe69	728	void lodepng_chunk_generate_crc(unsigned char* chunk);
embeddedartists	0:c828045bbe69	729
embeddedartists	0:c828045bbe69	730	/iterate to next chunks. don't use on IEND chunk, as there is no next chunk then/
embeddedartists	0:c828045bbe69	731	unsigned char* lodepng_chunk_next(unsigned char* chunk);
embeddedartists	0:c828045bbe69	732	const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk);
embeddedartists	0:c828045bbe69	733
embeddedartists	0:c828045bbe69	734	/*
embeddedartists	0:c828045bbe69	735	Appends chunk to the data in out. The given chunk should already have its chunk header.
embeddedartists	0:c828045bbe69	736	The out variable and outlength are updated to reflect the new reallocated buffer.
embeddedartists	0:c828045bbe69	737	Returns error code (0 if it went ok)
embeddedartists	0:c828045bbe69	738	*/
embeddedartists	0:c828045bbe69	739	unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk);
embeddedartists	0:c828045bbe69	740
embeddedartists	0:c828045bbe69	741	/*
embeddedartists	0:c828045bbe69	742	Appends new chunk to out. The chunk to append is given by giving its length, type
embeddedartists	0:c828045bbe69	743	and data separately. The type is a 4-letter string.
embeddedartists	0:c828045bbe69	744	The out variable and outlength are updated to reflect the new reallocated buffer.
embeddedartists	0:c828045bbe69	745	Returne error code (0 if it went ok)
embeddedartists	0:c828045bbe69	746	*/
embeddedartists	0:c828045bbe69	747	unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length,
embeddedartists	0:c828045bbe69	748	const char* type, const unsigned char* data);
embeddedartists	0:c828045bbe69	749
embeddedartists	0:c828045bbe69	750
embeddedartists	0:c828045bbe69	751	/Calculate CRC32 of buffer/
embeddedartists	0:c828045bbe69	752	unsigned lodepng_crc32(const unsigned char* buf, size_t len);
embeddedartists	0:c828045bbe69	753	#endif /LODEPNG_COMPILE_PNG/
embeddedartists	0:c828045bbe69	754
embeddedartists	0:c828045bbe69	755
embeddedartists	0:c828045bbe69	756	#ifdef LODEPNG_COMPILE_ZLIB
embeddedartists	0:c828045bbe69	757	/*
embeddedartists	0:c828045bbe69	758	This zlib part can be used independently to zlib compress and decompress a
embeddedartists	0:c828045bbe69	759	buffer. It cannot be used to create gzip files however, and it only supports the
embeddedartists	0:c828045bbe69	760	part of zlib that is required for PNG, it does not support dictionaries.
embeddedartists	0:c828045bbe69	761	*/
embeddedartists	0:c828045bbe69	762
embeddedartists	0:c828045bbe69	763	#ifdef LODEPNG_COMPILE_DECODER
embeddedartists	0:c828045bbe69	764	/Inflate a buffer. Inflate is the decompression step of deflate. Out buffer must be freed after use./
embeddedartists	0:c828045bbe69	765	unsigned lodepng_inflate(unsigned char** out, size_t* outsize,
embeddedartists	0:c828045bbe69	766	const unsigned char* in, size_t insize,
embeddedartists	0:c828045bbe69	767	const LodePNGDecompressSettings* settings);
embeddedartists	0:c828045bbe69	768
embeddedartists	0:c828045bbe69	769	/*
embeddedartists	0:c828045bbe69	770	Decompresses Zlib data. Reallocates the out buffer and appends the data. The
embeddedartists	0:c828045bbe69	771	data must be according to the zlib specification.
embeddedartists	0:c828045bbe69	772	Either, out must be NULL and outsize must be 0, or, *out must be a valid
embeddedartists	0:c828045bbe69	773	buffer and *outsize its size in bytes. out must be freed by user after usage.
embeddedartists	0:c828045bbe69	774	*/
embeddedartists	0:c828045bbe69	775	unsigned lodepng_zlib_decompress(unsigned char** out, size_t* outsize,
embeddedartists	0:c828045bbe69	776	const unsigned char* in, size_t insize,
embeddedartists	0:c828045bbe69	777	const LodePNGDecompressSettings* settings);
embeddedartists	0:c828045bbe69	778	#endif /LODEPNG_COMPILE_DECODER/
embeddedartists	0:c828045bbe69	779
embeddedartists	0:c828045bbe69	780	#ifdef LODEPNG_COMPILE_ENCODER
embeddedartists	0:c828045bbe69	781	/*
embeddedartists	0:c828045bbe69	782	Compresses data with Zlib. Reallocates the out buffer and appends the data.
embeddedartists	0:c828045bbe69	783	Zlib adds a small header and trailer around the deflate data.
embeddedartists	0:c828045bbe69	784	The data is output in the format of the zlib specification.
embeddedartists	0:c828045bbe69	785	Either, out must be NULL and outsize must be 0, or, *out must be a valid
embeddedartists	0:c828045bbe69	786	buffer and *outsize its size in bytes. out must be freed by user after usage.
embeddedartists	0:c828045bbe69	787	*/
embeddedartists	0:c828045bbe69	788	unsigned lodepng_zlib_compress(unsigned char** out, size_t* outsize,
embeddedartists	0:c828045bbe69	789	const unsigned char* in, size_t insize,
embeddedartists	0:c828045bbe69	790	const LodePNGCompressSettings* settings);
embeddedartists	0:c828045bbe69	791
embeddedartists	0:c828045bbe69	792	/*
embeddedartists	0:c828045bbe69	793	Find length-limited Huffman code for given frequencies. This function is in the
embeddedartists	0:c828045bbe69	794	public interface only for tests, it's used internally by lodepng_deflate.
embeddedartists	0:c828045bbe69	795	*/
embeddedartists	0:c828045bbe69	796	unsigned lodepng_huffman_code_lengths(unsigned* lengths, const unsigned* frequencies,
embeddedartists	0:c828045bbe69	797	size_t numcodes, unsigned maxbitlen);
embeddedartists	0:c828045bbe69	798
embeddedartists	0:c828045bbe69	799	/Compress a buffer with deflate. See RFC 1951. Out buffer must be freed after use./
embeddedartists	0:c828045bbe69	800	unsigned lodepng_deflate(unsigned char** out, size_t* outsize,
embeddedartists	0:c828045bbe69	801	const unsigned char* in, size_t insize,
embeddedartists	0:c828045bbe69	802	const LodePNGCompressSettings* settings);
embeddedartists	0:c828045bbe69	803
embeddedartists	0:c828045bbe69	804	#endif /LODEPNG_COMPILE_ENCODER/
embeddedartists	0:c828045bbe69	805	#endif /LODEPNG_COMPILE_ZLIB/
embeddedartists	0:c828045bbe69	806
embeddedartists	0:c828045bbe69	807	#ifdef LODEPNG_COMPILE_DISK
embeddedartists	0:c828045bbe69	808	/*
embeddedartists	0:c828045bbe69	809	Load a file from disk into buffer. The function allocates the out buffer, and
embeddedartists	0:c828045bbe69	810	after usage you should free it.
embeddedartists	0:c828045bbe69	811	out: output parameter, contains pointer to loaded buffer.
embeddedartists	0:c828045bbe69	812	outsize: output parameter, size of the allocated out buffer
embeddedartists	0:c828045bbe69	813	filename: the path to the file to load
embeddedartists	0:c828045bbe69	814	return value: error code (0 means ok)
embeddedartists	0:c828045bbe69	815	*/
embeddedartists	0:c828045bbe69	816	unsigned lodepng_load_file(unsigned char** out, size_t* outsize, const char* filename);
embeddedartists	0:c828045bbe69	817
embeddedartists	0:c828045bbe69	818	/*
embeddedartists	0:c828045bbe69	819	Save a file from buffer to disk. Warning, if it exists, this function overwrites
embeddedartists	0:c828045bbe69	820	the file without warning!
embeddedartists	0:c828045bbe69	821	buffer: the buffer to write
embeddedartists	0:c828045bbe69	822	buffersize: size of the buffer to write
embeddedartists	0:c828045bbe69	823	filename: the path to the file to save to
embeddedartists	0:c828045bbe69	824	return value: error code (0 means ok)
embeddedartists	0:c828045bbe69	825	*/
embeddedartists	0:c828045bbe69	826	unsigned lodepng_save_file(const unsigned char* buffer, size_t buffersize, const char* filename);
embeddedartists	0:c828045bbe69	827	#endif /LODEPNG_COMPILE_DISK/
embeddedartists	0:c828045bbe69	828
embeddedartists	0:c828045bbe69	829	#ifdef LODEPNG_COMPILE_CPP
embeddedartists	0:c828045bbe69	830	//The LodePNG C++ wrapper uses std::vectors instead of manually allocated memory buffers.
embeddedartists	0:c828045bbe69	831	namespace lodepng
embeddedartists	0:c828045bbe69	832	{
embeddedartists	0:c828045bbe69	833	#ifdef LODEPNG_COMPILE_PNG
embeddedartists	0:c828045bbe69	834	class State : public LodePNGState
embeddedartists	0:c828045bbe69	835	{
embeddedartists	0:c828045bbe69	836	public:
embeddedartists	0:c828045bbe69	837	State();
embeddedartists	0:c828045bbe69	838	State(const State& other);
embeddedartists	0:c828045bbe69	839	virtual ~State();
embeddedartists	0:c828045bbe69	840	State& operator=(const State& other);
embeddedartists	0:c828045bbe69	841	};
embeddedartists	0:c828045bbe69	842
embeddedartists	0:c828045bbe69	843	#ifdef LODEPNG_COMPILE_DECODER
embeddedartists	0:c828045bbe69	844	//Same as other lodepng::decode, but using a State for more settings and information.
embeddedartists	0:c828045bbe69	845	unsigned decode(std::vector<unsigned char>& out, unsigned& w, unsigned& h,
embeddedartists	0:c828045bbe69	846	State& state,
embeddedartists	0:c828045bbe69	847	const unsigned char* in, size_t insize);
embeddedartists	0:c828045bbe69	848	unsigned decode(std::vector<unsigned char>& out, unsigned& w, unsigned& h,
embeddedartists	0:c828045bbe69	849	State& state,
embeddedartists	0:c828045bbe69	850	const std::vector<unsigned char>& in);
embeddedartists	0:c828045bbe69	851	#endif /LODEPNG_COMPILE_DECODER/
embeddedartists	0:c828045bbe69	852
embeddedartists	0:c828045bbe69	853	#ifdef LODEPNG_COMPILE_ENCODER
embeddedartists	0:c828045bbe69	854	//Same as other lodepng::encode, but using a State for more settings and information.
embeddedartists	0:c828045bbe69	855	unsigned encode(std::vector<unsigned char>& out,
embeddedartists	0:c828045bbe69	856	const unsigned char* in, unsigned w, unsigned h,
embeddedartists	0:c828045bbe69	857	State& state);
embeddedartists	0:c828045bbe69	858	unsigned encode(std::vector<unsigned char>& out,
embeddedartists	0:c828045bbe69	859	const std::vector<unsigned char>& in, unsigned w, unsigned h,
embeddedartists	0:c828045bbe69	860	State& state);
embeddedartists	0:c828045bbe69	861	#endif /LODEPNG_COMPILE_ENCODER/
embeddedartists	0:c828045bbe69	862
embeddedartists	0:c828045bbe69	863	#ifdef LODEPNG_COMPILE_DISK
embeddedartists	0:c828045bbe69	864	/*
embeddedartists	0:c828045bbe69	865	Load a file from disk into an std::vector. If the vector is empty, then either
embeddedartists	0:c828045bbe69	866	the file doesn't exist or is an empty file.
embeddedartists	0:c828045bbe69	867	*/
embeddedartists	0:c828045bbe69	868	void load_file(std::vector<unsigned char>& buffer, const std::string& filename);
embeddedartists	0:c828045bbe69	869
embeddedartists	0:c828045bbe69	870	/*
embeddedartists	0:c828045bbe69	871	Save the binary data in an std::vector to a file on disk. The file is overwritten
embeddedartists	0:c828045bbe69	872	without warning.
embeddedartists	0:c828045bbe69	873	*/
embeddedartists	0:c828045bbe69	874	void save_file(const std::vector<unsigned char>& buffer, const std::string& filename);
embeddedartists	0:c828045bbe69	875	#endif //LODEPNG_COMPILE_DISK
embeddedartists	0:c828045bbe69	876	#endif //LODEPNG_COMPILE_PNG
embeddedartists	0:c828045bbe69	877
embeddedartists	0:c828045bbe69	878	#ifdef LODEPNG_COMPILE_ZLIB
embeddedartists	0:c828045bbe69	879	#ifdef LODEPNG_COMPILE_DECODER
embeddedartists	0:c828045bbe69	880	//Zlib-decompress an unsigned char buffer
embeddedartists	0:c828045bbe69	881	unsigned decompress(std::vector<unsigned char>& out, const unsigned char* in, size_t insize,
embeddedartists	0:c828045bbe69	882	const LodePNGDecompressSettings& settings = lodepng_default_decompress_settings);
embeddedartists	0:c828045bbe69	883
embeddedartists	0:c828045bbe69	884	//Zlib-decompress an std::vector
embeddedartists	0:c828045bbe69	885	unsigned decompress(std::vector<unsigned char>& out, const std::vector<unsigned char>& in,
embeddedartists	0:c828045bbe69	886	const LodePNGDecompressSettings& settings = lodepng_default_decompress_settings);
embeddedartists	0:c828045bbe69	887	#endif //LODEPNG_COMPILE_DECODER
embeddedartists	0:c828045bbe69	888
embeddedartists	0:c828045bbe69	889	#ifdef LODEPNG_COMPILE_ENCODER
embeddedartists	0:c828045bbe69	890	//Zlib-compress an unsigned char buffer
embeddedartists	0:c828045bbe69	891	unsigned compress(std::vector<unsigned char>& out, const unsigned char* in, size_t insize,
embeddedartists	0:c828045bbe69	892	const LodePNGCompressSettings& settings = lodepng_default_compress_settings);
embeddedartists	0:c828045bbe69	893
embeddedartists	0:c828045bbe69	894	//Zlib-compress an std::vector
embeddedartists	0:c828045bbe69	895	unsigned compress(std::vector<unsigned char>& out, const std::vector<unsigned char>& in,
embeddedartists	0:c828045bbe69	896	const LodePNGCompressSettings& settings = lodepng_default_compress_settings);
embeddedartists	0:c828045bbe69	897	#endif //LODEPNG_COMPILE_ENCODER
embeddedartists	0:c828045bbe69	898	#endif //LODEPNG_COMPILE_ZLIB
embeddedartists	0:c828045bbe69	899	} //namespace lodepng
embeddedartists	0:c828045bbe69	900	#endif /LODEPNG_COMPILE_CPP/
embeddedartists	0:c828045bbe69	901
embeddedartists	0:c828045bbe69	902	/*
embeddedartists	0:c828045bbe69	903	TODO:
embeddedartists	0:c828045bbe69	904	[.] test if there are no memory leaks or security exploits - done a lot but needs to be checked often
embeddedartists	0:c828045bbe69	905	[.] check compatibility with vareous compilers - done but needs to be redone for every newer version
embeddedartists	0:c828045bbe69	906	[X] converting color to 16-bit per channel types
embeddedartists	0:c828045bbe69	907	[ ] read all public PNG chunk types (but never let the color profile and gamma ones touch RGB values)
embeddedartists	0:c828045bbe69	908	[ ] make sure encoder generates no chunks with size > (2^31)-1
embeddedartists	0:c828045bbe69	909	[ ] partial decoding (stream processing)
embeddedartists	0:c828045bbe69	910	[X] let the "isFullyOpaque" function check color keys and transparent palettes too
embeddedartists	0:c828045bbe69	911	[X] better name for the variables "codes", "codesD", "codelengthcodes", "clcl" and "lldl"
embeddedartists	0:c828045bbe69	912	[ ] don't stop decoding on errors like 69, 57, 58 (make warnings)
embeddedartists	0:c828045bbe69	913	[ ] make option to choose if the raw image with non multiple of 8 bits per scanline should have padding bits or not
embeddedartists	0:c828045bbe69	914	[ ] let the C++ wrapper catch exceptions coming from the standard library and return LodePNG error codes
embeddedartists	0:c828045bbe69	915	*/
embeddedartists	0:c828045bbe69	916
embeddedartists	0:c828045bbe69	917	#endif /LODEPNG_H inclusion guard/
embeddedartists	0:c828045bbe69	918
embeddedartists	0:c828045bbe69	919	/*
embeddedartists	0:c828045bbe69	920	LodePNG Documentation
embeddedartists	0:c828045bbe69	921	---------------------
embeddedartists	0:c828045bbe69	922
embeddedartists	0:c828045bbe69	923	0. table of contents
embeddedartists	0:c828045bbe69	924	--------------------
embeddedartists	0:c828045bbe69	925
embeddedartists	0:c828045bbe69	926	1. about
embeddedartists	0:c828045bbe69	927	1.1. supported features
embeddedartists	0:c828045bbe69	928	1.2. features not supported
embeddedartists	0:c828045bbe69	929	2. C and C++ version
embeddedartists	0:c828045bbe69	930	3. security
embeddedartists	0:c828045bbe69	931	4. decoding
embeddedartists	0:c828045bbe69	932	5. encoding
embeddedartists	0:c828045bbe69	933	6. color conversions
embeddedartists	0:c828045bbe69	934	6.1. PNG color types
embeddedartists	0:c828045bbe69	935	6.2. color conversions
embeddedartists	0:c828045bbe69	936	6.3. padding bits
embeddedartists	0:c828045bbe69	937	6.4. A note about 16-bits per channel and endianness
embeddedartists	0:c828045bbe69	938	7. error values
embeddedartists	0:c828045bbe69	939	8. chunks and PNG editing
embeddedartists	0:c828045bbe69	940	9. compiler support
embeddedartists	0:c828045bbe69	941	10. examples
embeddedartists	0:c828045bbe69	942	10.1. decoder C++ example
embeddedartists	0:c828045bbe69	943	10.2. decoder C example
embeddedartists	0:c828045bbe69	944	11. changes
embeddedartists	0:c828045bbe69	945	12. contact information
embeddedartists	0:c828045bbe69	946
embeddedartists	0:c828045bbe69	947
embeddedartists	0:c828045bbe69	948	1. about
embeddedartists	0:c828045bbe69	949	--------
embeddedartists	0:c828045bbe69	950
embeddedartists	0:c828045bbe69	951	PNG is a file format to store raster images losslessly with good compression,
embeddedartists	0:c828045bbe69	952	supporting different color types and alpha channel.
embeddedartists	0:c828045bbe69	953
embeddedartists	0:c828045bbe69	954	LodePNG is a PNG codec according to the Portable Network Graphics (PNG)
embeddedartists	0:c828045bbe69	955	Specification (Second Edition) - W3C Recommendation 10 November 2003.
embeddedartists	0:c828045bbe69	956
embeddedartists	0:c828045bbe69	957	The specifications used are:
embeddedartists	0:c828045bbe69	958
embeddedartists	0:c828045bbe69	959	*) Portable Network Graphics (PNG) Specification (Second Edition):
embeddedartists	0:c828045bbe69	960	http://www.w3.org/TR/2003/REC-PNG-20031110
embeddedartists	0:c828045bbe69	961	*) RFC 1950 ZLIB Compressed Data Format version 3.3:
embeddedartists	0:c828045bbe69	962	http://www.gzip.org/zlib/rfc-zlib.html
embeddedartists	0:c828045bbe69	963	*) RFC 1951 DEFLATE Compressed Data Format Specification ver 1.3:
embeddedartists	0:c828045bbe69	964	http://www.gzip.org/zlib/rfc-deflate.html
embeddedartists	0:c828045bbe69	965
embeddedartists	0:c828045bbe69	966	The most recent version of LodePNG can currently be found at
embeddedartists	0:c828045bbe69	967	http://lodev.org/lodepng/
embeddedartists	0:c828045bbe69	968
embeddedartists	0:c828045bbe69	969	LodePNG works both in C (ISO C90) and C++, with a C++ wrapper that adds
embeddedartists	0:c828045bbe69	970	extra functionality.
embeddedartists	0:c828045bbe69	971
embeddedartists	0:c828045bbe69	972	LodePNG exists out of two files:
embeddedartists	0:c828045bbe69	973	-lodepng.h: the header file for both C and C++
embeddedartists	0:c828045bbe69	974	-lodepng.c(pp): give it the name lodepng.c or lodepng.cpp (or .cc) depending on your usage
embeddedartists	0:c828045bbe69	975
embeddedartists	0:c828045bbe69	976	If you want to start using LodePNG right away without reading this doc, get the
embeddedartists	0:c828045bbe69	977	examples from the LodePNG website to see how to use it in code, or check the
embeddedartists	0:c828045bbe69	978	smaller examples in chapter 13 here.
embeddedartists	0:c828045bbe69	979
embeddedartists	0:c828045bbe69	980	LodePNG is simple but only supports the basic requirements. To achieve
embeddedartists	0:c828045bbe69	981	simplicity, the following design choices were made: There are no dependencies
embeddedartists	0:c828045bbe69	982	on any external library. There are functions to decode and encode a PNG with
embeddedartists	0:c828045bbe69	983	a single function call, and extended versions of these functions taking a
embeddedartists	0:c828045bbe69	984	LodePNGState struct allowing to specify or get more information. By default
embeddedartists	0:c828045bbe69	985	the colors of the raw image are always RGB or RGBA, no matter what color type
embeddedartists	0:c828045bbe69	986	the PNG file uses. To read and write files, there are simple functions to
embeddedartists	0:c828045bbe69	987	convert the files to/from buffers in memory.
embeddedartists	0:c828045bbe69	988
embeddedartists	0:c828045bbe69	989	This all makes LodePNG suitable for loading textures in games, demos and small
embeddedartists	0:c828045bbe69	990	programs, ... It's less suitable for full fledged image editors, loading PNGs
embeddedartists	0:c828045bbe69	991	over network (it requires all the image data to be available before decoding can
embeddedartists	0:c828045bbe69	992	begin), life-critical systems, ...
embeddedartists	0:c828045bbe69	993
embeddedartists	0:c828045bbe69	994	1.1. supported features
embeddedartists	0:c828045bbe69	995	-----------------------
embeddedartists	0:c828045bbe69	996
embeddedartists	0:c828045bbe69	997	The following features are supported by the decoder:
embeddedartists	0:c828045bbe69	998
embeddedartists	0:c828045bbe69	999	*) decoding of PNGs with any color type, bit depth and interlace mode, to a 24- or 32-bit color raw image,
embeddedartists	0:c828045bbe69	1000	or the same color type as the PNG
embeddedartists	0:c828045bbe69	1001	*) encoding of PNGs, from any raw image to 24- or 32-bit color, or the same color type as the raw image
embeddedartists	0:c828045bbe69	1002	*) Adam7 interlace and deinterlace for any color type
embeddedartists	0:c828045bbe69	1003	*) loading the image from harddisk or decoding it from a buffer from other sources than harddisk
embeddedartists	0:c828045bbe69	1004	*) support for alpha channels, including RGBA color model, translucent palettes and color keying
embeddedartists	0:c828045bbe69	1005	*) zlib decompression (inflate)
embeddedartists	0:c828045bbe69	1006	*) zlib compression (deflate)
embeddedartists	0:c828045bbe69	1007	*) CRC32 and ADLER32 checksums
embeddedartists	0:c828045bbe69	1008	*) handling of unknown chunks, allowing making a PNG editor that stores custom and unknown chunks.
embeddedartists	0:c828045bbe69	1009	*) the following chunks are supported (generated/interpreted) by both encoder and decoder:
embeddedartists	0:c828045bbe69	1010	IHDR: header information
embeddedartists	0:c828045bbe69	1011	PLTE: color palette
embeddedartists	0:c828045bbe69	1012	IDAT: pixel data
embeddedartists	0:c828045bbe69	1013	IEND: the final chunk
embeddedartists	0:c828045bbe69	1014	tRNS: transparency for palettized images
embeddedartists	0:c828045bbe69	1015	tEXt: textual information
embeddedartists	0:c828045bbe69	1016	zTXt: compressed textual information
embeddedartists	0:c828045bbe69	1017	iTXt: international textual information
embeddedartists	0:c828045bbe69	1018	bKGD: suggested background color
embeddedartists	0:c828045bbe69	1019	pHYs: physical dimensions
embeddedartists	0:c828045bbe69	1020	tIME: modification time
embeddedartists	0:c828045bbe69	1021
embeddedartists	0:c828045bbe69	1022	1.2. features not supported
embeddedartists	0:c828045bbe69	1023	---------------------------
embeddedartists	0:c828045bbe69	1024
embeddedartists	0:c828045bbe69	1025	The following features are _not_ supported:
embeddedartists	0:c828045bbe69	1026
embeddedartists	0:c828045bbe69	1027	*) some features needed to make a conformant PNG-Editor might be still missing.
embeddedartists	0:c828045bbe69	1028	*) partial loading/stream processing. All data must be available and is processed in one call.
embeddedartists	0:c828045bbe69	1029	*) The following public chunks are not supported but treated as unknown chunks by LodePNG
embeddedartists	0:c828045bbe69	1030	cHRM, gAMA, iCCP, sRGB, sBIT, hIST, sPLT
embeddedartists	0:c828045bbe69	1031	Some of these are not supported on purpose: LodePNG wants to provide the RGB values
embeddedartists	0:c828045bbe69	1032	stored in the pixels, not values modified by system dependent gamma or color models.
embeddedartists	0:c828045bbe69	1033
embeddedartists	0:c828045bbe69	1034
embeddedartists	0:c828045bbe69	1035	2. C and C++ version
embeddedartists	0:c828045bbe69	1036	--------------------
embeddedartists	0:c828045bbe69	1037
embeddedartists	0:c828045bbe69	1038	The C version uses buffers allocated with alloc that you need to free()
embeddedartists	0:c828045bbe69	1039	yourself. You need to use init and cleanup functions for each struct whenever
embeddedartists	0:c828045bbe69	1040	using a struct from the C version to avoid exploits and memory leaks.
embeddedartists	0:c828045bbe69	1041
embeddedartists	0:c828045bbe69	1042	The C++ version has extra functions with std::vectors in the interface and the
embeddedartists	0:c828045bbe69	1043	lodepng::State class which is a LodePNGState with constructor and destructor.
embeddedartists	0:c828045bbe69	1044
embeddedartists	0:c828045bbe69	1045	These files work without modification for both C and C++ compilers because all
embeddedartists	0:c828045bbe69	1046	the additional C++ code is in "#ifdef __cplusplus" blocks that make C-compilers
embeddedartists	0:c828045bbe69	1047	ignore it, and the C code is made to compile both with strict ISO C90 and C++.
embeddedartists	0:c828045bbe69	1048
embeddedartists	0:c828045bbe69	1049	To use the C++ version, you need to rename the source file to lodepng.cpp
embeddedartists	0:c828045bbe69	1050	(instead of lodepng.c), and compile it with a C++ compiler.
embeddedartists	0:c828045bbe69	1051
embeddedartists	0:c828045bbe69	1052	To use the C version, you need to rename the source file to lodepng.c (instead
embeddedartists	0:c828045bbe69	1053	of lodepng.cpp), and compile it with a C compiler.
embeddedartists	0:c828045bbe69	1054
embeddedartists	0:c828045bbe69	1055
embeddedartists	0:c828045bbe69	1056	3. Security
embeddedartists	0:c828045bbe69	1057	-----------
embeddedartists	0:c828045bbe69	1058
embeddedartists	0:c828045bbe69	1059	Even if carefully designed, it's always possible that LodePNG contains possible
embeddedartists	0:c828045bbe69	1060	exploits. If you discover one, please let me know, and it will be fixed.
embeddedartists	0:c828045bbe69	1061
embeddedartists	0:c828045bbe69	1062	When using LodePNG, care has to be taken with the C version of LodePNG, as well
embeddedartists	0:c828045bbe69	1063	as the C-style structs when working with C++. The following conventions are used
embeddedartists	0:c828045bbe69	1064	for all C-style structs:
embeddedartists	0:c828045bbe69	1065
embeddedartists	0:c828045bbe69	1066	-if a struct has a corresponding init function, always call the init function when making a new one
embeddedartists	0:c828045bbe69	1067	-if a struct has a corresponding cleanup function, call it before the struct disappears to avoid memory leaks
embeddedartists	0:c828045bbe69	1068	-if a struct has a corresponding copy function, use the copy function instead of "=".
embeddedartists	0:c828045bbe69	1069	The destination must also be inited already.
embeddedartists	0:c828045bbe69	1070
embeddedartists	0:c828045bbe69	1071
embeddedartists	0:c828045bbe69	1072	4. Decoding
embeddedartists	0:c828045bbe69	1073	-----------
embeddedartists	0:c828045bbe69	1074
embeddedartists	0:c828045bbe69	1075	Decoding converts a PNG compressed image to a raw pixel buffer.
embeddedartists	0:c828045bbe69	1076
embeddedartists	0:c828045bbe69	1077	Most documentation on using the decoder is at its declarations in the header
embeddedartists	0:c828045bbe69	1078	above. For C, simple decoding can be done with functions such as
embeddedartists	0:c828045bbe69	1079	lodepng_decode32, and more advanced decoding can be done with the struct
embeddedartists	0:c828045bbe69	1080	LodePNGState and lodepng_decode. For C++, all decoding can be done with the
embeddedartists	0:c828045bbe69	1081	various lodepng::decode functions, and lodepng::State can be used for advanced
embeddedartists	0:c828045bbe69	1082	features.
embeddedartists	0:c828045bbe69	1083
embeddedartists	0:c828045bbe69	1084	When using the LodePNGState, it uses the following fields for decoding:
embeddedartists	0:c828045bbe69	1085	*) LodePNGInfo info_png: it stores extra information about the PNG (the input) in here
embeddedartists	0:c828045bbe69	1086	*) LodePNGColorMode info_raw: here you can say what color mode of the raw image (the output) you want to get
embeddedartists	0:c828045bbe69	1087	*) LodePNGDecoderSettings decoder: you can specify a few extra settings for the decoder to use
embeddedartists	0:c828045bbe69	1088
embeddedartists	0:c828045bbe69	1089	LodePNGInfo info_png
embeddedartists	0:c828045bbe69	1090	--------------------
embeddedartists	0:c828045bbe69	1091
embeddedartists	0:c828045bbe69	1092	After decoding, this contains extra information of the PNG image, except the actual
embeddedartists	0:c828045bbe69	1093	pixels, width and height because these are already gotten directly from the decoder
embeddedartists	0:c828045bbe69	1094	functions.
embeddedartists	0:c828045bbe69	1095
embeddedartists	0:c828045bbe69	1096	It contains for example the original color type of the PNG image, text comments,
embeddedartists	0:c828045bbe69	1097	suggested background color, etc... More details about the LodePNGInfo struct are
embeddedartists	0:c828045bbe69	1098	at its declaration documentation.
embeddedartists	0:c828045bbe69	1099
embeddedartists	0:c828045bbe69	1100	LodePNGColorMode info_raw
embeddedartists	0:c828045bbe69	1101	-------------------------
embeddedartists	0:c828045bbe69	1102
embeddedartists	0:c828045bbe69	1103	When decoding, here you can specify which color type you want
embeddedartists	0:c828045bbe69	1104	the resulting raw image to be. If this is different from the colortype of the
embeddedartists	0:c828045bbe69	1105	PNG, then the decoder will automatically convert the result. This conversion
embeddedartists	0:c828045bbe69	1106	always works, except if you want it to convert a color PNG to greyscale or to
embeddedartists	0:c828045bbe69	1107	a palette with missing colors.
embeddedartists	0:c828045bbe69	1108
embeddedartists	0:c828045bbe69	1109	By default, 32-bit color is used for the result.
embeddedartists	0:c828045bbe69	1110
embeddedartists	0:c828045bbe69	1111	LodePNGDecoderSettings decoder
embeddedartists	0:c828045bbe69	1112	------------------------------
embeddedartists	0:c828045bbe69	1113
embeddedartists	0:c828045bbe69	1114	The settings can be used to ignore the errors created by invalid CRC and Adler32
embeddedartists	0:c828045bbe69	1115	chunks, and to disable the decoding of tEXt chunks.
embeddedartists	0:c828045bbe69	1116
embeddedartists	0:c828045bbe69	1117	There's also a setting color_convert, true by default. If false, no conversion
embeddedartists	0:c828045bbe69	1118	is done, the resulting data will be as it was in the PNG (after decompression)
embeddedartists	0:c828045bbe69	1119	and you'll have to puzzle the colors of the pixels together yourself using the
embeddedartists	0:c828045bbe69	1120	color type information in the LodePNGInfo.
embeddedartists	0:c828045bbe69	1121
embeddedartists	0:c828045bbe69	1122
embeddedartists	0:c828045bbe69	1123	5. Encoding
embeddedartists	0:c828045bbe69	1124	-----------
embeddedartists	0:c828045bbe69	1125
embeddedartists	0:c828045bbe69	1126	Encoding converts a raw pixel buffer to a PNG compressed image.
embeddedartists	0:c828045bbe69	1127
embeddedartists	0:c828045bbe69	1128	Most documentation on using the encoder is at its declarations in the header
embeddedartists	0:c828045bbe69	1129	above. For C, simple encoding can be done with functions such as
embeddedartists	0:c828045bbe69	1130	lodepng_encode32, and more advanced decoding can be done with the struct
embeddedartists	0:c828045bbe69	1131	LodePNGState and lodepng_encode. For C++, all encoding can be done with the
embeddedartists	0:c828045bbe69	1132	various lodepng::encode functions, and lodepng::State can be used for advanced
embeddedartists	0:c828045bbe69	1133	features.
embeddedartists	0:c828045bbe69	1134
embeddedartists	0:c828045bbe69	1135	Like the decoder, the encoder can also give errors. However it gives less errors
embeddedartists	0:c828045bbe69	1136	since the encoder input is trusted, the decoder input (a PNG image that could
embeddedartists	0:c828045bbe69	1137	be forged by anyone) is not trusted.
embeddedartists	0:c828045bbe69	1138
embeddedartists	0:c828045bbe69	1139	When using the LodePNGState, it uses the following fields for encoding:
embeddedartists	0:c828045bbe69	1140	*) LodePNGInfo info_png: here you specify how you want the PNG (the output) to be.
embeddedartists	0:c828045bbe69	1141	*) LodePNGColorMode info_raw: here you say what color type of the raw image (the input) has
embeddedartists	0:c828045bbe69	1142	*) LodePNGEncoderSettings encoder: you can specify a few settings for the encoder to use
embeddedartists	0:c828045bbe69	1143
embeddedartists	0:c828045bbe69	1144	LodePNGInfo info_png
embeddedartists	0:c828045bbe69	1145	--------------------
embeddedartists	0:c828045bbe69	1146
embeddedartists	0:c828045bbe69	1147	When encoding, you use this the opposite way as when decoding: for encoding,
embeddedartists	0:c828045bbe69	1148	you fill in the values you want the PNG to have before encoding. By default it's
embeddedartists	0:c828045bbe69	1149	not needed to specify a color type for the PNG since it's automatically chosen,
embeddedartists	0:c828045bbe69	1150	but it's possible to choose it yourself given the right settings.
embeddedartists	0:c828045bbe69	1151
embeddedartists	0:c828045bbe69	1152	The encoder will not always exactly match the LodePNGInfo struct you give,
embeddedartists	0:c828045bbe69	1153	it tries as close as possible. Some things are ignored by the encoder. The
embeddedartists	0:c828045bbe69	1154	encoder uses, for example, the following settings from it when applicable:
embeddedartists	0:c828045bbe69	1155	colortype and bitdepth, text chunks, time chunk, the color key, the palette, the
embeddedartists	0:c828045bbe69	1156	background color, the interlace method, unknown chunks, ...
embeddedartists	0:c828045bbe69	1157
embeddedartists	0:c828045bbe69	1158	When encoding to a PNG with colortype 3, the encoder will generate a PLTE chunk.
embeddedartists	0:c828045bbe69	1159	If the palette contains any colors for which the alpha channel is not 255 (so
embeddedartists	0:c828045bbe69	1160	there are translucent colors in the palette), it'll add a tRNS chunk.
embeddedartists	0:c828045bbe69	1161
embeddedartists	0:c828045bbe69	1162	LodePNGColorMode info_raw
embeddedartists	0:c828045bbe69	1163	-------------------------
embeddedartists	0:c828045bbe69	1164
embeddedartists	0:c828045bbe69	1165	You specify the color type of the raw image that you give to the input here,
embeddedartists	0:c828045bbe69	1166	including a possible transparent color key and palette you happen to be using in
embeddedartists	0:c828045bbe69	1167	your raw image data.
embeddedartists	0:c828045bbe69	1168
embeddedartists	0:c828045bbe69	1169	By default, 32-bit color is assumed, meaning your input has to be in RGBA
embeddedartists	0:c828045bbe69	1170	format with 4 bytes (unsigned chars) per pixel.
embeddedartists	0:c828045bbe69	1171
embeddedartists	0:c828045bbe69	1172	LodePNGEncoderSettings encoder
embeddedartists	0:c828045bbe69	1173	------------------------------
embeddedartists	0:c828045bbe69	1174
embeddedartists	0:c828045bbe69	1175	The following settings are supported (some are in sub-structs):
embeddedartists	0:c828045bbe69	1176	*) auto_convert: when this option is enabled, the encoder will
embeddedartists	0:c828045bbe69	1177	automatically choose the smallest possible color mode (including color key) that
embeddedartists	0:c828045bbe69	1178	can encode the colors of all pixels without information loss.
embeddedartists	0:c828045bbe69	1179	*) btype: the block type for LZ77. 0 = uncompressed, 1 = fixed huffman tree,
embeddedartists	0:c828045bbe69	1180	2 = dynamic huffman tree (best compression). Should be 2 for proper
embeddedartists	0:c828045bbe69	1181	compression.
embeddedartists	0:c828045bbe69	1182	*) use_lz77: whether or not to use LZ77 for compressed block types. Should be
embeddedartists	0:c828045bbe69	1183	true for proper compression.
embeddedartists	0:c828045bbe69	1184	*) windowsize: the window size used by the LZ77 encoder (1 - 32768). Has value
embeddedartists	0:c828045bbe69	1185	2048 by default, but can be set to 32768 for better, but slow, compression.
embeddedartists	0:c828045bbe69	1186	*) force_palette: if colortype is 2 or 6, you can make the encoder write a PLTE
embeddedartists	0:c828045bbe69	1187	chunk if force_palette is true. This can used as suggested palette to convert
embeddedartists	0:c828045bbe69	1188	to by viewers that don't support more than 256 colors (if those still exist)
embeddedartists	0:c828045bbe69	1189	*) add_id: add text chunk "Encoder: LodePNG <version>" to the image.
embeddedartists	0:c828045bbe69	1190	*) text_compression: default 1. If 1, it'll store texts as zTXt instead of tEXt chunks.
embeddedartists	0:c828045bbe69	1191	zTXt chunks use zlib compression on the text. This gives a smaller result on
embeddedartists	0:c828045bbe69	1192	large texts but a larger result on small texts (such as a single program name).
embeddedartists	0:c828045bbe69	1193	It's all tEXt or all zTXt though, there's no separate setting per text yet.
embeddedartists	0:c828045bbe69	1194
embeddedartists	0:c828045bbe69	1195
embeddedartists	0:c828045bbe69	1196	6. color conversions
embeddedartists	0:c828045bbe69	1197	--------------------
embeddedartists	0:c828045bbe69	1198
embeddedartists	0:c828045bbe69	1199	An important thing to note about LodePNG, is that the color type of the PNG, and
embeddedartists	0:c828045bbe69	1200	the color type of the raw image, are completely independent. By default, when
embeddedartists	0:c828045bbe69	1201	you decode a PNG, you get the result as a raw image in the color type you want,
embeddedartists	0:c828045bbe69	1202	no matter whether the PNG was encoded with a palette, greyscale or RGBA color.
embeddedartists	0:c828045bbe69	1203	And if you encode an image, by default LodePNG will automatically choose the PNG
embeddedartists	0:c828045bbe69	1204	color type that gives good compression based on the values of colors and amount
embeddedartists	0:c828045bbe69	1205	of colors in the image. It can be configured to let you control it instead as
embeddedartists	0:c828045bbe69	1206	well, though.
embeddedartists	0:c828045bbe69	1207
embeddedartists	0:c828045bbe69	1208	To be able to do this, LodePNG does conversions from one color mode to another.
embeddedartists	0:c828045bbe69	1209	It can convert from almost any color type to any other color type, except the
embeddedartists	0:c828045bbe69	1210	following conversions: RGB to greyscale is not supported, and converting to a
embeddedartists	0:c828045bbe69	1211	palette when the palette doesn't have a required color is not supported. This is
embeddedartists	0:c828045bbe69	1212	not supported on purpose: this is information loss which requires a color
embeddedartists	0:c828045bbe69	1213	reduction algorithm that is beyong the scope of a PNG encoder (yes, RGB to grey
embeddedartists	0:c828045bbe69	1214	is easy, but there are multiple ways if you want to give some channels more
embeddedartists	0:c828045bbe69	1215	weight).
embeddedartists	0:c828045bbe69	1216
embeddedartists	0:c828045bbe69	1217	By default, when decoding, you get the raw image in 32-bit RGBA or 24-bit RGB
embeddedartists	0:c828045bbe69	1218	color, no matter what color type the PNG has. And by default when encoding,
embeddedartists	0:c828045bbe69	1219	LodePNG automatically picks the best color model for the output PNG, and expects
embeddedartists	0:c828045bbe69	1220	the input image to be 32-bit RGBA or 24-bit RGB. So, unless you want to control
embeddedartists	0:c828045bbe69	1221	the color format of the images yourself, you can skip this chapter.
embeddedartists	0:c828045bbe69	1222
embeddedartists	0:c828045bbe69	1223	6.1. PNG color types
embeddedartists	0:c828045bbe69	1224	--------------------
embeddedartists	0:c828045bbe69	1225
embeddedartists	0:c828045bbe69	1226	A PNG image can have many color types, ranging from 1-bit color to 64-bit color,
embeddedartists	0:c828045bbe69	1227	as well as palettized color modes. After the zlib decompression and unfiltering
embeddedartists	0:c828045bbe69	1228	in the PNG image is done, the raw pixel data will have that color type and thus
embeddedartists	0:c828045bbe69	1229	a certain amount of bits per pixel. If you want the output raw image after
embeddedartists	0:c828045bbe69	1230	decoding to have another color type, a conversion is done by LodePNG.
embeddedartists	0:c828045bbe69	1231
embeddedartists	0:c828045bbe69	1232	The PNG specification gives the following color types:
embeddedartists	0:c828045bbe69	1233
embeddedartists	0:c828045bbe69	1234	0: greyscale, bit depths 1, 2, 4, 8, 16
embeddedartists	0:c828045bbe69	1235	2: RGB, bit depths 8 and 16
embeddedartists	0:c828045bbe69	1236	3: palette, bit depths 1, 2, 4 and 8
embeddedartists	0:c828045bbe69	1237	4: greyscale with alpha, bit depths 8 and 16
embeddedartists	0:c828045bbe69	1238	6: RGBA, bit depths 8 and 16
embeddedartists	0:c828045bbe69	1239
embeddedartists	0:c828045bbe69	1240	Bit depth is the amount of bits per pixel per color channel. So the total amount
embeddedartists	0:c828045bbe69	1241	of bits per pixel is: amount of channels * bitdepth.
embeddedartists	0:c828045bbe69	1242
embeddedartists	0:c828045bbe69	1243	6.2. color conversions
embeddedartists	0:c828045bbe69	1244	----------------------
embeddedartists	0:c828045bbe69	1245
embeddedartists	0:c828045bbe69	1246	As explained in the sections about the encoder and decoder, you can specify
embeddedartists	0:c828045bbe69	1247	color types and bit depths in info_png and info_raw to change the default
embeddedartists	0:c828045bbe69	1248	behaviour.
embeddedartists	0:c828045bbe69	1249
embeddedartists	0:c828045bbe69	1250	If, when decoding, you want the raw image to be something else than the default,
embeddedartists	0:c828045bbe69	1251	you need to set the color type and bit depth you want in the LodePNGColorMode,
embeddedartists	0:c828045bbe69	1252	or the parameters of the simple function of LodePNG you're using.
embeddedartists	0:c828045bbe69	1253
embeddedartists	0:c828045bbe69	1254	If, when encoding, you use another color type than the default in the input
embeddedartists	0:c828045bbe69	1255	image, you need to specify its color type and bit depth in the LodePNGColorMode
embeddedartists	0:c828045bbe69	1256	of the raw image, or use the parameters of the simplefunction of LodePNG you're
embeddedartists	0:c828045bbe69	1257	using.
embeddedartists	0:c828045bbe69	1258
embeddedartists	0:c828045bbe69	1259	If, when encoding, you don't want LodePNG to choose the output PNG color type
embeddedartists	0:c828045bbe69	1260	but control it yourself, you need to set auto_convert in the encoder settings
embeddedartists	0:c828045bbe69	1261	to LAC_NONE, and specify the color type you want in the LodePNGInfo of the
embeddedartists	0:c828045bbe69	1262	encoder.
embeddedartists	0:c828045bbe69	1263
embeddedartists	0:c828045bbe69	1264	If you do any of the above, LodePNG may need to do a color conversion, which
embeddedartists	0:c828045bbe69	1265	follows the rules below, and may sometimes not be allowed.
embeddedartists	0:c828045bbe69	1266
embeddedartists	0:c828045bbe69	1267	To avoid some confusion:
embeddedartists	0:c828045bbe69	1268	-the decoder converts from PNG to raw image
embeddedartists	0:c828045bbe69	1269	-the encoder converts from raw image to PNG
embeddedartists	0:c828045bbe69	1270	-the colortype and bitdepth in LodePNGColorMode info_raw, are those of the raw image
embeddedartists	0:c828045bbe69	1271	-the colortype and bitdepth in the color field of LodePNGInfo info_png, are those of the PNG
embeddedartists	0:c828045bbe69	1272	-when encoding, the color type in LodePNGInfo is ignored if auto_convert
embeddedartists	0:c828045bbe69	1273	is enabled, it is automatically generated instead
embeddedartists	0:c828045bbe69	1274	-when decoding, the color type in LodePNGInfo is set by the decoder to that of the original
embeddedartists	0:c828045bbe69	1275	PNG image, but it can be ignored since the raw image has the color type you requested instead
embeddedartists	0:c828045bbe69	1276	-if the color type of the LodePNGColorMode and PNG image aren't the same, a conversion
embeddedartists	0:c828045bbe69	1277	between the color types is done if the color types are supported. If it is not
embeddedartists	0:c828045bbe69	1278	supported, an error is returned. If the types are the same, no conversion is done.
embeddedartists	0:c828045bbe69	1279	-even though some conversions aren't supported, LodePNG supports loading PNGs from any
embeddedartists	0:c828045bbe69	1280	colortype and saving PNGs to any colortype, sometimes it just requires preparing
embeddedartists	0:c828045bbe69	1281	the raw image correctly before encoding.
embeddedartists	0:c828045bbe69	1282	-both encoder and decoder use the same color converter.
embeddedartists	0:c828045bbe69	1283
embeddedartists	0:c828045bbe69	1284	Non supported color conversions:
embeddedartists	0:c828045bbe69	1285	-color to greyscale: no error is thrown, but the result will look ugly because
embeddedartists	0:c828045bbe69	1286	only the red channel is taken
embeddedartists	0:c828045bbe69	1287	-anything, to palette when that palette does not have that color in it: in this
embeddedartists	0:c828045bbe69	1288	case an error is thrown
embeddedartists	0:c828045bbe69	1289
embeddedartists	0:c828045bbe69	1290	Supported color conversions:
embeddedartists	0:c828045bbe69	1291	-anything to 8-bit RGB, 8-bit RGBA, 16-bit RGB, 16-bit RGBA
embeddedartists	0:c828045bbe69	1292	-any grey or grey+alpha, to grey or grey+alpha
embeddedartists	0:c828045bbe69	1293	-anything to a palette, as long as the palette has the requested colors in it
embeddedartists	0:c828045bbe69	1294	-removing alpha channel
embeddedartists	0:c828045bbe69	1295	-higher to smaller bitdepth, and vice versa
embeddedartists	0:c828045bbe69	1296
embeddedartists	0:c828045bbe69	1297	If you want no color conversion to be done:
embeddedartists	0:c828045bbe69	1298	-In the encoder, you can make it save a PNG with any color type by giving the
embeddedartists	0:c828045bbe69	1299	raw color mode and LodePNGInfo the same color mode, and setting auto_convert to
embeddedartists	0:c828045bbe69	1300	LAC_NO.
embeddedartists	0:c828045bbe69	1301	-In the decoder, you can make it store the pixel data in the same color type
embeddedartists	0:c828045bbe69	1302	as the PNG has, by setting the color_convert setting to false. Settings in
embeddedartists	0:c828045bbe69	1303	info_raw are then ignored.
embeddedartists	0:c828045bbe69	1304
embeddedartists	0:c828045bbe69	1305	The function lodepng_convert does the color conversion. It is available in the
embeddedartists	0:c828045bbe69	1306	interface but normally isn't needed since the encoder and decoder already call
embeddedartists	0:c828045bbe69	1307	it.
embeddedartists	0:c828045bbe69	1308
embeddedartists	0:c828045bbe69	1309	6.3. padding bits
embeddedartists	0:c828045bbe69	1310	-----------------
embeddedartists	0:c828045bbe69	1311
embeddedartists	0:c828045bbe69	1312	In the PNG file format, if a less than 8-bit per pixel color type is used and the scanlines
embeddedartists	0:c828045bbe69	1313	have a bit amount that isn't a multiple of 8, then padding bits are used so that each
embeddedartists	0:c828045bbe69	1314	scanline starts at a fresh byte. But that is NOT true for the LodePNG raw input and output.
embeddedartists	0:c828045bbe69	1315	The raw input image you give to the encoder, and the raw output image you get from the decoder
embeddedartists	0:c828045bbe69	1316	will NOT have these padding bits, e.g. in the case of a 1-bit image with a width
embeddedartists	0:c828045bbe69	1317	of 7 pixels, the first pixel of the second scanline will the the 8th bit of the first byte,
embeddedartists	0:c828045bbe69	1318	not the first bit of a new byte.
embeddedartists	0:c828045bbe69	1319
embeddedartists	0:c828045bbe69	1320	6.4. A note about 16-bits per channel and endianness
embeddedartists	0:c828045bbe69	1321	----------------------------------------------------
embeddedartists	0:c828045bbe69	1322
embeddedartists	0:c828045bbe69	1323	LodePNG uses unsigned char arrays for 16-bit per channel colors too, just like
embeddedartists	0:c828045bbe69	1324	for any other color format. The 16-bit values are stored in big endian (most
embeddedartists	0:c828045bbe69	1325	significant byte first) in these arrays. This is the opposite order of the
embeddedartists	0:c828045bbe69	1326	little endian used by x86 CPU's.
embeddedartists	0:c828045bbe69	1327
embeddedartists	0:c828045bbe69	1328	LodePNG always uses big endian because the PNG file format does so internally.
embeddedartists	0:c828045bbe69	1329	Conversions to other formats than PNG uses internally are not supported by
embeddedartists	0:c828045bbe69	1330	LodePNG on purpose, there are myriads of formats, including endianness of 16-bit
embeddedartists	0:c828045bbe69	1331	colors, the order in which you store R, G, B and A, and so on. Supporting and
embeddedartists	0:c828045bbe69	1332	converting to/from all that is outside the scope of LodePNG.
embeddedartists	0:c828045bbe69	1333
embeddedartists	0:c828045bbe69	1334	This may mean that, depending on your use case, you may want to convert the big
embeddedartists	0:c828045bbe69	1335	endian output of LodePNG to little endian with a for loop. This is certainly not
embeddedartists	0:c828045bbe69	1336	always needed, many applications and libraries support big endian 16-bit colors
embeddedartists	0:c828045bbe69	1337	anyway, but it means you cannot simply cast the unsigned char* buffer to an
embeddedartists	0:c828045bbe69	1338	unsigned short* buffer on x86 CPUs.
embeddedartists	0:c828045bbe69	1339
embeddedartists	0:c828045bbe69	1340
embeddedartists	0:c828045bbe69	1341	7. error values
embeddedartists	0:c828045bbe69	1342	---------------
embeddedartists	0:c828045bbe69	1343
embeddedartists	0:c828045bbe69	1344	All functions in LodePNG that return an error code, return 0 if everything went
embeddedartists	0:c828045bbe69	1345	OK, or a non-zero code if there was an error.
embeddedartists	0:c828045bbe69	1346
embeddedartists	0:c828045bbe69	1347	The meaning of the LodePNG error values can be retrieved with the function
embeddedartists	0:c828045bbe69	1348	lodepng_error_text: given the numerical error code, it returns a description
embeddedartists	0:c828045bbe69	1349	of the error in English as a string.
embeddedartists	0:c828045bbe69	1350
embeddedartists	0:c828045bbe69	1351	Check the implementation of lodepng_error_text to see the meaning of each code.
embeddedartists	0:c828045bbe69	1352
embeddedartists	0:c828045bbe69	1353
embeddedartists	0:c828045bbe69	1354	8. chunks and PNG editing
embeddedartists	0:c828045bbe69	1355	-------------------------
embeddedartists	0:c828045bbe69	1356
embeddedartists	0:c828045bbe69	1357	If you want to add extra chunks to a PNG you encode, or use LodePNG for a PNG
embeddedartists	0:c828045bbe69	1358	editor that should follow the rules about handling of unknown chunks, or if your
embeddedartists	0:c828045bbe69	1359	program is able to read other types of chunks than the ones handled by LodePNG,
embeddedartists	0:c828045bbe69	1360	then that's possible with the chunk functions of LodePNG.
embeddedartists	0:c828045bbe69	1361
embeddedartists	0:c828045bbe69	1362	A PNG chunk has the following layout:
embeddedartists	0:c828045bbe69	1363
embeddedartists	0:c828045bbe69	1364	4 bytes length
embeddedartists	0:c828045bbe69	1365	4 bytes type name
embeddedartists	0:c828045bbe69	1366	length bytes data
embeddedartists	0:c828045bbe69	1367	4 bytes CRC
embeddedartists	0:c828045bbe69	1368
embeddedartists	0:c828045bbe69	1369	8.1. iterating through chunks
embeddedartists	0:c828045bbe69	1370	-----------------------------
embeddedartists	0:c828045bbe69	1371
embeddedartists	0:c828045bbe69	1372	If you have a buffer containing the PNG image data, then the first chunk (the
embeddedartists	0:c828045bbe69	1373	IHDR chunk) starts at byte number 8 of that buffer. The first 8 bytes are the
embeddedartists	0:c828045bbe69	1374	signature of the PNG and are not part of a chunk. But if you start at byte 8
embeddedartists	0:c828045bbe69	1375	then you have a chunk, and can check the following things of it.
embeddedartists	0:c828045bbe69	1376
embeddedartists	0:c828045bbe69	1377	NOTE: none of these functions check for memory buffer boundaries. To avoid
embeddedartists	0:c828045bbe69	1378	exploits, always make sure the buffer contains all the data of the chunks.
embeddedartists	0:c828045bbe69	1379	When using lodepng_chunk_next, make sure the returned value is within the
embeddedartists	0:c828045bbe69	1380	allocated memory.
embeddedartists	0:c828045bbe69	1381
embeddedartists	0:c828045bbe69	1382	unsigned lodepng_chunk_length(const unsigned char* chunk):
embeddedartists	0:c828045bbe69	1383
embeddedartists	0:c828045bbe69	1384	Get the length of the chunk's data. The total chunk length is this length + 12.
embeddedartists	0:c828045bbe69	1385
embeddedartists	0:c828045bbe69	1386	void lodepng_chunk_type(char type[5], const unsigned char* chunk):
embeddedartists	0:c828045bbe69	1387	unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type):
embeddedartists	0:c828045bbe69	1388
embeddedartists	0:c828045bbe69	1389	Get the type of the chunk or compare if it's a certain type
embeddedartists	0:c828045bbe69	1390
embeddedartists	0:c828045bbe69	1391	unsigned char lodepng_chunk_critical(const unsigned char* chunk):
embeddedartists	0:c828045bbe69	1392	unsigned char lodepng_chunk_private(const unsigned char* chunk):
embeddedartists	0:c828045bbe69	1393	unsigned char lodepng_chunk_safetocopy(const unsigned char* chunk):
embeddedartists	0:c828045bbe69	1394
embeddedartists	0:c828045bbe69	1395	Check if the chunk is critical in the PNG standard (only IHDR, PLTE, IDAT and IEND are).
embeddedartists	0:c828045bbe69	1396	Check if the chunk is private (public chunks are part of the standard, private ones not).
embeddedartists	0:c828045bbe69	1397	Check if the chunk is safe to copy. If it's not, then, when modifying data in a critical
embeddedartists	0:c828045bbe69	1398	chunk, unsafe to copy chunks of the old image may NOT be saved in the new one if your
embeddedartists	0:c828045bbe69	1399	program doesn't handle that type of unknown chunk.
embeddedartists	0:c828045bbe69	1400
embeddedartists	0:c828045bbe69	1401	unsigned char* lodepng_chunk_data(unsigned char* chunk):
embeddedartists	0:c828045bbe69	1402	const unsigned char* lodepng_chunk_data_const(const unsigned char* chunk):
embeddedartists	0:c828045bbe69	1403
embeddedartists	0:c828045bbe69	1404	Get a pointer to the start of the data of the chunk.
embeddedartists	0:c828045bbe69	1405
embeddedartists	0:c828045bbe69	1406	unsigned lodepng_chunk_check_crc(const unsigned char* chunk):
embeddedartists	0:c828045bbe69	1407	void lodepng_chunk_generate_crc(unsigned char* chunk):
embeddedartists	0:c828045bbe69	1408
embeddedartists	0:c828045bbe69	1409	Check if the crc is correct or generate a correct one.
embeddedartists	0:c828045bbe69	1410
embeddedartists	0:c828045bbe69	1411	unsigned char* lodepng_chunk_next(unsigned char* chunk):
embeddedartists	0:c828045bbe69	1412	const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk):
embeddedartists	0:c828045bbe69	1413
embeddedartists	0:c828045bbe69	1414	Iterate to the next chunk. This works if you have a buffer with consecutive chunks. Note that these
embeddedartists	0:c828045bbe69	1415	functions do no boundary checking of the allocated data whatsoever, so make sure there is enough
embeddedartists	0:c828045bbe69	1416	data available in the buffer to be able to go to the next chunk.
embeddedartists	0:c828045bbe69	1417
embeddedartists	0:c828045bbe69	1418	unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk):
embeddedartists	0:c828045bbe69	1419	unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length,
embeddedartists	0:c828045bbe69	1420	const char* type, const unsigned char* data):
embeddedartists	0:c828045bbe69	1421
embeddedartists	0:c828045bbe69	1422	These functions are used to create new chunks that are appended to the data in *out that has
embeddedartists	0:c828045bbe69	1423	length *outlength. The append function appends an existing chunk to the new data. The create
embeddedartists	0:c828045bbe69	1424	function creates a new chunk with the given parameters and appends it. Type is the 4-letter
embeddedartists	0:c828045bbe69	1425	name of the chunk.
embeddedartists	0:c828045bbe69	1426
embeddedartists	0:c828045bbe69	1427	8.2. chunks in info_png
embeddedartists	0:c828045bbe69	1428	-----------------------
embeddedartists	0:c828045bbe69	1429
embeddedartists	0:c828045bbe69	1430	The LodePNGInfo struct contains fields with the unknown chunk in it. It has 3
embeddedartists	0:c828045bbe69	1431	buffers (each with size) to contain 3 types of unknown chunks:
embeddedartists	0:c828045bbe69	1432	the ones that come before the PLTE chunk, the ones that come between the PLTE
embeddedartists	0:c828045bbe69	1433	and the IDAT chunks, and the ones that come after the IDAT chunks.
embeddedartists	0:c828045bbe69	1434	It's necessary to make the distionction between these 3 cases because the PNG
embeddedartists	0:c828045bbe69	1435	standard forces to keep the ordering of unknown chunks compared to the critical
embeddedartists	0:c828045bbe69	1436	chunks, but does not force any other ordering rules.
embeddedartists	0:c828045bbe69	1437
embeddedartists	0:c828045bbe69	1438	info_png.unknown_chunks_data[0] is the chunks before PLTE
embeddedartists	0:c828045bbe69	1439	info_png.unknown_chunks_data[1] is the chunks after PLTE, before IDAT
embeddedartists	0:c828045bbe69	1440	info_png.unknown_chunks_data[2] is the chunks after IDAT
embeddedartists	0:c828045bbe69	1441
embeddedartists	0:c828045bbe69	1442	The chunks in these 3 buffers can be iterated through and read by using the same
embeddedartists	0:c828045bbe69	1443	way described in the previous subchapter.
embeddedartists	0:c828045bbe69	1444
embeddedartists	0:c828045bbe69	1445	When using the decoder to decode a PNG, you can make it store all unknown chunks
embeddedartists	0:c828045bbe69	1446	if you set the option settings.remember_unknown_chunks to 1. By default, this
embeddedartists	0:c828045bbe69	1447	option is off (0).
embeddedartists	0:c828045bbe69	1448
embeddedartists	0:c828045bbe69	1449	The encoder will always encode unknown chunks that are stored in the info_png.
embeddedartists	0:c828045bbe69	1450	If you need it to add a particular chunk that isn't known by LodePNG, you can
embeddedartists	0:c828045bbe69	1451	use lodepng_chunk_append or lodepng_chunk_create to the chunk data in
embeddedartists	0:c828045bbe69	1452	info_png.unknown_chunks_data[x].
embeddedartists	0:c828045bbe69	1453
embeddedartists	0:c828045bbe69	1454	Chunks that are known by LodePNG should not be added in that way. E.g. to make
embeddedartists	0:c828045bbe69	1455	LodePNG add a bKGD chunk, set background_defined to true and add the correct
embeddedartists	0:c828045bbe69	1456	parameters there instead.
embeddedartists	0:c828045bbe69	1457
embeddedartists	0:c828045bbe69	1458
embeddedartists	0:c828045bbe69	1459	9. compiler support
embeddedartists	0:c828045bbe69	1460	-------------------
embeddedartists	0:c828045bbe69	1461
embeddedartists	0:c828045bbe69	1462	No libraries other than the current standard C library are needed to compile
embeddedartists	0:c828045bbe69	1463	LodePNG. For the C++ version, only the standard C++ library is needed on top.
embeddedartists	0:c828045bbe69	1464	Add the files lodepng.c(pp) and lodepng.h to your project, include
embeddedartists	0:c828045bbe69	1465	lodepng.h where needed, and your program can read/write PNG files.
embeddedartists	0:c828045bbe69	1466
embeddedartists	0:c828045bbe69	1467	If performance is important, use optimization when compiling! For both the
embeddedartists	0:c828045bbe69	1468	encoder and decoder, this makes a large difference.
embeddedartists	0:c828045bbe69	1469
embeddedartists	0:c828045bbe69	1470	Make sure that LodePNG is compiled with the same compiler of the same version
embeddedartists	0:c828045bbe69	1471	and with the same settings as the rest of the program, or the interfaces with
embeddedartists	0:c828045bbe69	1472	std::vectors and std::strings in C++ can be incompatible.
embeddedartists	0:c828045bbe69	1473
embeddedartists	0:c828045bbe69	1474	CHAR_BITS must be 8 or higher, because LodePNG uses unsigned chars for octets.
embeddedartists	0:c828045bbe69	1475
embeddedartists	0:c828045bbe69	1476	*) gcc and g++
embeddedartists	0:c828045bbe69	1477
embeddedartists	0:c828045bbe69	1478	LodePNG is developed in gcc so this compiler is natively supported. It gives no
embeddedartists	0:c828045bbe69	1479	warnings with compiler options "-Wall -Wextra -pedantic -ansi", with gcc and g++
embeddedartists	0:c828045bbe69	1480	version 4.7.1 on Linux, 32-bit and 64-bit.
embeddedartists	0:c828045bbe69	1481
embeddedartists	0:c828045bbe69	1482	*) Mingw
embeddedartists	0:c828045bbe69	1483
embeddedartists	0:c828045bbe69	1484	The Mingw compiler (a port of gcc) for Windows is fully supported by LodePNG.
embeddedartists	0:c828045bbe69	1485
embeddedartists	0:c828045bbe69	1486	*) Visual Studio 2005 and up, Visual C++ Express Edition 2005 and up
embeddedartists	0:c828045bbe69	1487
embeddedartists	0:c828045bbe69	1488	Visual Studio may give warnings about 'fopen' being deprecated. A multiplatform library
embeddedartists	0:c828045bbe69	1489	can't support the proposed Visual Studio alternative however, so LodePNG keeps using
embeddedartists	0:c828045bbe69	1490	fopen. If you don't want to see the deprecated warnings, put this on top of lodepng.h
embeddedartists	0:c828045bbe69	1491	before the inclusions:
embeddedartists	0:c828045bbe69	1492	#define _CRT_SECURE_NO_DEPRECATE
embeddedartists	0:c828045bbe69	1493
embeddedartists	0:c828045bbe69	1494	Other than the above warnings, LodePNG should be warning-free with warning
embeddedartists	0:c828045bbe69	1495	level 3 (W3). Warning level 4 (W4) will give warnings about integer conversions.
embeddedartists	0:c828045bbe69	1496	I'm not planning to resolve these warnings. To get rid of them, let Visual
embeddedartists	0:c828045bbe69	1497	Studio use warning level W3 for lodepng.cpp only: right click lodepng.cpp,
embeddedartists	0:c828045bbe69	1498	Properties, C/C++, General, Warning Level: Level 3 (/W3).
embeddedartists	0:c828045bbe69	1499
embeddedartists	0:c828045bbe69	1500	Visual Studio may want "stdafx.h" files to be included in each source file and
embeddedartists	0:c828045bbe69	1501	give an error "unexpected end of file while looking for precompiled header".
embeddedartists	0:c828045bbe69	1502	That is not standard C++ and will not be added to the stock LodePNG. You can
embeddedartists	0:c828045bbe69	1503	disable it for lodepng.cpp only by right clicking it, Properties, C/C++,
embeddedartists	0:c828045bbe69	1504	Precompiled Headers, and set it to Not Using Precompiled Headers there.
embeddedartists	0:c828045bbe69	1505
embeddedartists	0:c828045bbe69	1506	*) Visual Studio 6.0
embeddedartists	0:c828045bbe69	1507
embeddedartists	0:c828045bbe69	1508	LodePNG support for Visual Studio 6.0 is not guaranteed because VS6 doesn't
embeddedartists	0:c828045bbe69	1509	follow the C++ standard correctly.
embeddedartists	0:c828045bbe69	1510
embeddedartists	0:c828045bbe69	1511	*) Comeau C/C++
embeddedartists	0:c828045bbe69	1512
embeddedartists	0:c828045bbe69	1513	Vesion 20070107 compiles without problems on the Comeau C/C++ Online Test Drive
embeddedartists	0:c828045bbe69	1514	at http://www.comeaucomputing.com/tryitout in both C90 and C++ mode.
embeddedartists	0:c828045bbe69	1515
embeddedartists	0:c828045bbe69	1516	*) Compilers on Macintosh
embeddedartists	0:c828045bbe69	1517
embeddedartists	0:c828045bbe69	1518	LodePNG has been reported to work both with the gcc and LLVM for Macintosh, both
embeddedartists	0:c828045bbe69	1519	for C and C++.
embeddedartists	0:c828045bbe69	1520
embeddedartists	0:c828045bbe69	1521	*) Other Compilers
embeddedartists	0:c828045bbe69	1522
embeddedartists	0:c828045bbe69	1523	If you encounter problems on other compilers, feel free to let me know and I may
embeddedartists	0:c828045bbe69	1524	try to fix it if the compiler is modern standards complient.
embeddedartists	0:c828045bbe69	1525
embeddedartists	0:c828045bbe69	1526
embeddedartists	0:c828045bbe69	1527	10. examples
embeddedartists	0:c828045bbe69	1528	------------
embeddedartists	0:c828045bbe69	1529
embeddedartists	0:c828045bbe69	1530	This decoder example shows the most basic usage of LodePNG. More complex
embeddedartists	0:c828045bbe69	1531	examples can be found on the LodePNG website.
embeddedartists	0:c828045bbe69	1532
embeddedartists	0:c828045bbe69	1533	10.1. decoder C++ example
embeddedartists	0:c828045bbe69	1534	-------------------------
embeddedartists	0:c828045bbe69	1535
embeddedartists	0:c828045bbe69	1536	#include "lodepng.h"
embeddedartists	0:c828045bbe69	1537	#include <iostream>
embeddedartists	0:c828045bbe69	1538
embeddedartists	0:c828045bbe69	1539	int main(int argc, char *argv[])
embeddedartists	0:c828045bbe69	1540	{
embeddedartists	0:c828045bbe69	1541	const char* filename = argc > 1 ? argv[1] : "test.png";
embeddedartists	0:c828045bbe69	1542
embeddedartists	0:c828045bbe69	1543	//load and decode
embeddedartists	0:c828045bbe69	1544	std::vector<unsigned char> image;
embeddedartists	0:c828045bbe69	1545	unsigned width, height;
embeddedartists	0:c828045bbe69	1546	unsigned error = lodepng::decode(image, width, height, filename);
embeddedartists	0:c828045bbe69	1547
embeddedartists	0:c828045bbe69	1548	//if there's an error, display it
embeddedartists	0:c828045bbe69	1549	if(error) std::cout << "decoder error " << error << ": " << lodepng_error_text(error) << std::endl;
embeddedartists	0:c828045bbe69	1550
embeddedartists	0:c828045bbe69	1551	//the pixels are now in the vector "image", 4 bytes per pixel, ordered RGBARGBA..., use it as texture, draw it, ...
embeddedartists	0:c828045bbe69	1552	}
embeddedartists	0:c828045bbe69	1553
embeddedartists	0:c828045bbe69	1554	10.2. decoder C example
embeddedartists	0:c828045bbe69	1555	-----------------------
embeddedartists	0:c828045bbe69	1556
embeddedartists	0:c828045bbe69	1557	#include "lodepng.h"
embeddedartists	0:c828045bbe69	1558
embeddedartists	0:c828045bbe69	1559	int main(int argc, char *argv[])
embeddedartists	0:c828045bbe69	1560	{
embeddedartists	0:c828045bbe69	1561	unsigned error;
embeddedartists	0:c828045bbe69	1562	unsigned char* image;
embeddedartists	0:c828045bbe69	1563	size_t width, height;
embeddedartists	0:c828045bbe69	1564	const char* filename = argc > 1 ? argv[1] : "test.png";
embeddedartists	0:c828045bbe69	1565
embeddedartists	0:c828045bbe69	1566	error = lodepng_decode32_file(&image, &width, &height, filename);
embeddedartists	0:c828045bbe69	1567
embeddedartists	0:c828045bbe69	1568	if(error) printf("decoder error %u: %s\n", error, lodepng_error_text(error));
embeddedartists	0:c828045bbe69	1569
embeddedartists	0:c828045bbe69	1570	/ * use image here * /
embeddedartists	0:c828045bbe69	1571
embeddedartists	0:c828045bbe69	1572	free(image);
embeddedartists	0:c828045bbe69	1573	return 0;
embeddedartists	0:c828045bbe69	1574	}
embeddedartists	0:c828045bbe69	1575
embeddedartists	0:c828045bbe69	1576
embeddedartists	0:c828045bbe69	1577	11. changes
embeddedartists	0:c828045bbe69	1578	-----------
embeddedartists	0:c828045bbe69	1579
embeddedartists	0:c828045bbe69	1580	The version number of LodePNG is the date of the change given in the format
embeddedartists	0:c828045bbe69	1581	yyyymmdd.
embeddedartists	0:c828045bbe69	1582
embeddedartists	0:c828045bbe69	1583	Some changes aren't backwards compatible. Those are indicated with a (!)
embeddedartists	0:c828045bbe69	1584	symbol.
embeddedartists	0:c828045bbe69	1585
embeddedartists	0:c828045bbe69	1586	*) 22 dec 2013: Power of two windowsize required for optimization.
embeddedartists	0:c828045bbe69	1587	*) 15 apr 2013: Fixed bug with LAC_ALPHA and color key.
embeddedartists	0:c828045bbe69	1588	*) 25 mar 2013: Added an optional feature to ignore some PNG errors (fix_png).
embeddedartists	0:c828045bbe69	1589	*) 11 mar 2013 (!): Bugfix with custom free. Changed from "my" to "lodepng_"
embeddedartists	0:c828045bbe69	1590	prefix for the custom allocators and made it possible with a new #define to
embeddedartists	0:c828045bbe69	1591	use custom ones in your project without needing to change lodepng's code.
embeddedartists	0:c828045bbe69	1592	*) 28 jan 2013: Bugfix with color key.
embeddedartists	0:c828045bbe69	1593	*) 27 okt 2012: Tweaks in text chunk keyword length error handling.
embeddedartists	0:c828045bbe69	1594	*) 8 okt 2012 (!): Added new filter strategy (entropy) and new auto color mode.
embeddedartists	0:c828045bbe69	1595	(no palette). Better deflate tree encoding. New compression tweak settings.
embeddedartists	0:c828045bbe69	1596	Faster color conversions while decoding. Some internal cleanups.
embeddedartists	0:c828045bbe69	1597	*) 23 sep 2012: Reduced warnings in Visual Studio a little bit.
embeddedartists	0:c828045bbe69	1598	*) 1 sep 2012 (!): Removed #define's for giving custom (de)compression functions
embeddedartists	0:c828045bbe69	1599	and made it work with function pointers instead.
embeddedartists	0:c828045bbe69	1600	*) 23 jun 2012: Added more filter strategies. Made it easier to use custom alloc
embeddedartists	0:c828045bbe69	1601	and free functions and toggle #defines from compiler flags. Small fixes.
embeddedartists	0:c828045bbe69	1602	*) 6 may 2012 (!): Made plugging in custom zlib/deflate functions more flexible.
embeddedartists	0:c828045bbe69	1603	*) 22 apr 2012 (!): Made interface more consistent, renaming a lot. Removed
embeddedartists	0:c828045bbe69	1604	redundant C++ codec classes. Reduced amount of structs. Everything changed,
embeddedartists	0:c828045bbe69	1605	but it is cleaner now imho and functionality remains the same. Also fixed
embeddedartists	0:c828045bbe69	1606	several bugs and shrinked the implementation code. Made new samples.
embeddedartists	0:c828045bbe69	1607	*) 6 nov 2011 (!): By default, the encoder now automatically chooses the best
embeddedartists	0:c828045bbe69	1608	PNG color model and bit depth, based on the amount and type of colors of the
embeddedartists	0:c828045bbe69	1609	raw image. For this, autoLeaveOutAlphaChannel replaced by auto_choose_color.
embeddedartists	0:c828045bbe69	1610	*) 9 okt 2011: simpler hash chain implementation for the encoder.
embeddedartists	0:c828045bbe69	1611	*) 8 sep 2011: lz77 encoder lazy matching instead of greedy matching.
embeddedartists	0:c828045bbe69	1612	*) 23 aug 2011: tweaked the zlib compression parameters after benchmarking.
embeddedartists	0:c828045bbe69	1613	A bug with the PNG filtertype heuristic was fixed, so that it chooses much
embeddedartists	0:c828045bbe69	1614	better ones (it's quite significant). A setting to do an experimental, slow,
embeddedartists	0:c828045bbe69	1615	brute force search for PNG filter types is added.
embeddedartists	0:c828045bbe69	1616	*) 17 aug 2011 (!): changed some C zlib related function names.
embeddedartists	0:c828045bbe69	1617	*) 16 aug 2011: made the code less wide (max 120 characters per line).
embeddedartists	0:c828045bbe69	1618	*) 17 apr 2011: code cleanup. Bugfixes. Convert low to 16-bit per sample colors.
embeddedartists	0:c828045bbe69	1619	*) 21 feb 2011: fixed compiling for C90. Fixed compiling with sections disabled.
embeddedartists	0:c828045bbe69	1620	*) 11 dec 2010: encoding is made faster, based on suggestion by Peter Eastman
embeddedartists	0:c828045bbe69	1621	to optimize long sequences of zeros.
embeddedartists	0:c828045bbe69	1622	*) 13 nov 2010: added LodePNG_InfoColor_hasPaletteAlpha and
embeddedartists	0:c828045bbe69	1623	LodePNG_InfoColor_canHaveAlpha functions for convenience.
embeddedartists	0:c828045bbe69	1624	*) 7 nov 2010: added LodePNG_error_text function to get error code description.
embeddedartists	0:c828045bbe69	1625	*) 30 okt 2010: made decoding slightly faster
embeddedartists	0:c828045bbe69	1626	*) 26 okt 2010: (!) changed some C function and struct names (more consistent).
embeddedartists	0:c828045bbe69	1627	Reorganized the documentation and the declaration order in the header.
embeddedartists	0:c828045bbe69	1628	*) 08 aug 2010: only changed some comments and external samples.
embeddedartists	0:c828045bbe69	1629	*) 05 jul 2010: fixed bug thanks to warnings in the new gcc version.
embeddedartists	0:c828045bbe69	1630	*) 14 mar 2010: fixed bug where too much memory was allocated for char buffers.
embeddedartists	0:c828045bbe69	1631	*) 02 sep 2008: fixed bug where it could create empty tree that linux apps could
embeddedartists	0:c828045bbe69	1632	read by ignoring the problem but windows apps couldn't.
embeddedartists	0:c828045bbe69	1633	*) 06 jun 2008: added more error checks for out of memory cases.
embeddedartists	0:c828045bbe69	1634	*) 26 apr 2008: added a few more checks here and there to ensure more safety.
embeddedartists	0:c828045bbe69	1635	*) 06 mar 2008: crash with encoding of strings fixed
embeddedartists	0:c828045bbe69	1636	*) 02 feb 2008: support for international text chunks added (iTXt)
embeddedartists	0:c828045bbe69	1637	*) 23 jan 2008: small cleanups, and #defines to divide code in sections
embeddedartists	0:c828045bbe69	1638	*) 20 jan 2008: support for unknown chunks allowing using LodePNG for an editor.
embeddedartists	0:c828045bbe69	1639	*) 18 jan 2008: support for tIME and pHYs chunks added to encoder and decoder.
embeddedartists	0:c828045bbe69	1640	*) 17 jan 2008: ability to encode and decode compressed zTXt chunks added
embeddedartists	0:c828045bbe69	1641	Also vareous fixes, such as in the deflate and the padding bits code.
embeddedartists	0:c828045bbe69	1642	*) 13 jan 2008: Added ability to encode Adam7-interlaced images. Improved
embeddedartists	0:c828045bbe69	1643	filtering code of encoder.
embeddedartists	0:c828045bbe69	1644	*) 07 jan 2008: (!) changed LodePNG to use ISO C90 instead of C++. A
embeddedartists	0:c828045bbe69	1645	C++ wrapper around this provides an interface almost identical to before.
embeddedartists	0:c828045bbe69	1646	Having LodePNG be pure ISO C90 makes it more portable. The C and C++ code
embeddedartists	0:c828045bbe69	1647	are together in these files but it works both for C and C++ compilers.
embeddedartists	0:c828045bbe69	1648	*) 29 dec 2007: (!) changed most integer types to unsigned int + other tweaks
embeddedartists	0:c828045bbe69	1649	*) 30 aug 2007: bug fixed which makes this Borland C++ compatible
embeddedartists	0:c828045bbe69	1650	*) 09 aug 2007: some VS2005 warnings removed again
embeddedartists	0:c828045bbe69	1651	*) 21 jul 2007: deflate code placed in new namespace separate from zlib code
embeddedartists	0:c828045bbe69	1652	*) 08 jun 2007: fixed bug with 2- and 4-bit color, and small interlaced images
embeddedartists	0:c828045bbe69	1653	*) 04 jun 2007: improved support for Visual Studio 2005: crash with accessing
embeddedartists	0:c828045bbe69	1654	invalid std::vector element [0] fixed, and level 3 and 4 warnings removed
embeddedartists	0:c828045bbe69	1655	*) 02 jun 2007: made the encoder add a tag with version by default
embeddedartists	0:c828045bbe69	1656	*) 27 may 2007: zlib and png code separated (but still in the same file),
embeddedartists	0:c828045bbe69	1657	simple encoder/decoder functions added for more simple usage cases
embeddedartists	0:c828045bbe69	1658	*) 19 may 2007: minor fixes, some code cleaning, new error added (error 69),
embeddedartists	0:c828045bbe69	1659	moved some examples from here to lodepng_examples.cpp
embeddedartists	0:c828045bbe69	1660	*) 12 may 2007: palette decoding bug fixed
embeddedartists	0:c828045bbe69	1661	*) 24 apr 2007: changed the license from BSD to the zlib license
embeddedartists	0:c828045bbe69	1662	*) 11 mar 2007: very simple addition: ability to encode bKGD chunks.
embeddedartists	0:c828045bbe69	1663	*) 04 mar 2007: (!) tEXt chunk related fixes, and support for encoding
embeddedartists	0:c828045bbe69	1664	palettized PNG images. Plus little interface change with palette and texts.
embeddedartists	0:c828045bbe69	1665	*) 03 mar 2007: Made it encode dynamic Huffman shorter with repeat codes.
embeddedartists	0:c828045bbe69	1666	Fixed a bug where the end code of a block had length 0 in the Huffman tree.
embeddedartists	0:c828045bbe69	1667	*) 26 feb 2007: Huffman compression with dynamic trees (BTYPE 2) now implemented
embeddedartists	0:c828045bbe69	1668	and supported by the encoder, resulting in smaller PNGs at the output.
embeddedartists	0:c828045bbe69	1669	*) 27 jan 2007: Made the Adler-32 test faster so that a timewaste is gone.
embeddedartists	0:c828045bbe69	1670	*) 24 jan 2007: gave encoder an error interface. Added color conversion from any
embeddedartists	0:c828045bbe69	1671	greyscale type to 8-bit greyscale with or without alpha.
embeddedartists	0:c828045bbe69	1672	*) 21 jan 2007: (!) Totally changed the interface. It allows more color types
embeddedartists	0:c828045bbe69	1673	to convert to and is more uniform. See the manual for how it works now.
embeddedartists	0:c828045bbe69	1674	*) 07 jan 2007: Some cleanup & fixes, and a few changes over the last days:
embeddedartists	0:c828045bbe69	1675	encode/decode custom tEXt chunks, separate classes for zlib & deflate, and
embeddedartists	0:c828045bbe69	1676	at last made the decoder give errors for incorrect Adler32 or Crc.
embeddedartists	0:c828045bbe69	1677	*) 01 jan 2007: Fixed bug with encoding PNGs with less than 8 bits per channel.
embeddedartists	0:c828045bbe69	1678	*) 29 dec 2006: Added support for encoding images without alpha channel, and
embeddedartists	0:c828045bbe69	1679	cleaned out code as well as making certain parts faster.
embeddedartists	0:c828045bbe69	1680	*) 28 dec 2006: Added "Settings" to the encoder.
embeddedartists	0:c828045bbe69	1681	*) 26 dec 2006: The encoder now does LZ77 encoding and produces much smaller files now.
embeddedartists	0:c828045bbe69	1682	Removed some code duplication in the decoder. Fixed little bug in an example.
embeddedartists	0:c828045bbe69	1683	*) 09 dec 2006: (!) Placed output parameters of public functions as first parameter.
embeddedartists	0:c828045bbe69	1684	Fixed a bug of the decoder with 16-bit per color.
embeddedartists	0:c828045bbe69	1685	*) 15 okt 2006: Changed documentation structure
embeddedartists	0:c828045bbe69	1686	*) 09 okt 2006: Encoder class added. It encodes a valid PNG image from the
embeddedartists	0:c828045bbe69	1687	given image buffer, however for now it's not compressed.
embeddedartists	0:c828045bbe69	1688	*) 08 sep 2006: (!) Changed to interface with a Decoder class
embeddedartists	0:c828045bbe69	1689	*) 30 jul 2006: (!) LodePNG_InfoPng , width and height are now retrieved in different
embeddedartists	0:c828045bbe69	1690	way. Renamed decodePNG to decodePNGGeneric.
embeddedartists	0:c828045bbe69	1691	*) 29 jul 2006: (!) Changed the interface: image info is now returned as a
embeddedartists	0:c828045bbe69	1692	struct of type LodePNG::LodePNG_Info, instead of a vector, which was a bit clumsy.
embeddedartists	0:c828045bbe69	1693	*) 28 jul 2006: Cleaned the code and added new error checks.
embeddedartists	0:c828045bbe69	1694	Corrected terminology "deflate" into "inflate".
embeddedartists	0:c828045bbe69	1695	*) 23 jun 2006: Added SDL example in the documentation in the header, this
embeddedartists	0:c828045bbe69	1696	example allows easy debugging by displaying the PNG and its transparency.
embeddedartists	0:c828045bbe69	1697	*) 22 jun 2006: (!) Changed way to obtain error value. Added
embeddedartists	0:c828045bbe69	1698	loadFile function for convenience. Made decodePNG32 faster.
embeddedartists	0:c828045bbe69	1699	*) 21 jun 2006: (!) Changed type of info vector to unsigned.
embeddedartists	0:c828045bbe69	1700	Changed position of palette in info vector. Fixed an important bug that
embeddedartists	0:c828045bbe69	1701	happened on PNGs with an uncompressed block.
embeddedartists	0:c828045bbe69	1702	*) 16 jun 2006: Internally changed unsigned into unsigned where
embeddedartists	0:c828045bbe69	1703	needed, and performed some optimizations.
embeddedartists	0:c828045bbe69	1704	*) 07 jun 2006: (!) Renamed functions to decodePNG and placed them
embeddedartists	0:c828045bbe69	1705	in LodePNG namespace. Changed the order of the parameters. Rewrote the
embeddedartists	0:c828045bbe69	1706	documentation in the header. Renamed files to lodepng.cpp and lodepng.h
embeddedartists	0:c828045bbe69	1707	*) 22 apr 2006: Optimized and improved some code
embeddedartists	0:c828045bbe69	1708	*) 07 sep 2005: (!) Changed to std::vector interface
embeddedartists	0:c828045bbe69	1709	*) 12 aug 2005: Initial release (C++, decoder only)
embeddedartists	0:c828045bbe69	1710
embeddedartists	0:c828045bbe69	1711
embeddedartists	0:c828045bbe69	1712	12. contact information
embeddedartists	0:c828045bbe69	1713	-----------------------
embeddedartists	0:c828045bbe69	1714
embeddedartists	0:c828045bbe69	1715	Feel free to contact me with suggestions, problems, comments, ... concerning
embeddedartists	0:c828045bbe69	1716	LodePNG. If you encounter a PNG image that doesn't work properly with this
embeddedartists	0:c828045bbe69	1717	decoder, feel free to send it and I'll use it to find and fix the problem.
embeddedartists	0:c828045bbe69	1718
embeddedartists	0:c828045bbe69	1719	My email address is (puzzle the account and domain together with an @ symbol):
embeddedartists	0:c828045bbe69	1720	Domain: gmail dot com.
embeddedartists	0:c828045bbe69	1721	Account: lode dot vandevenne.
embeddedartists	0:c828045bbe69	1722
embeddedartists	0:c828045bbe69	1723
embeddedartists	0:c828045bbe69	1724	Copyright (c) 2005-2013 Lode Vandevenne
embeddedartists	0:c828045bbe69	1725	*/

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Type:	Program
Mbed OS support:	Mbed 2 deprecated
Created:	03 Oct 2014
Imports:	60
Forks:	0
Commits:	1
Dependents:	0
Dependencies:	2
Followers:	1

lodepng.h@0:c828045bbe69, 2014-10-03 (annotated)

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