/* pngstruct.h - header file for PNG reference library | |
* | |
* Copyright (c) 1998-2013 Glenn Randers-Pehrson | |
* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) | |
* (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) | |
* | |
* Last changed in libpng 1.6.1 [March 28, 2013] | |
* | |
* This code is released under the libpng license. | |
* For conditions of distribution and use, see the disclaimer | |
* and license in png.h | |
*/ | |
/* The structure that holds the information to read and write PNG files. | |
* The only people who need to care about what is inside of this are the | |
* people who will be modifying the library for their own special needs. | |
* It should NOT be accessed directly by an application. | |
*/ | |
#ifndef PNGSTRUCT_H | |
#define PNGSTRUCT_H | |
/* zlib.h defines the structure z_stream, an instance of which is included | |
* in this structure and is required for decompressing the LZ compressed | |
* data in PNG files. | |
*/ | |
#ifndef ZLIB_CONST | |
/* We must ensure that zlib uses 'const' in declarations. */ | |
# define ZLIB_CONST | |
#endif | |
#include "third_party/zlib_v128/zlib.h" | |
#ifdef const | |
/* zlib.h sometimes #defines const to nothing, undo this. */ | |
# undef const | |
#endif | |
/* zlib.h has mediocre z_const use before 1.2.6, this stuff is for compatibility | |
* with older builds. | |
*/ | |
#if ZLIB_VERNUM < 0x1260 | |
# define PNGZ_MSG_CAST(s) png_constcast(char*,s) | |
# define PNGZ_INPUT_CAST(b) png_constcast(png_bytep,b) | |
#else | |
# define PNGZ_MSG_CAST(s) (s) | |
# define PNGZ_INPUT_CAST(b) (b) | |
#endif | |
/* zlib.h declares a magic type 'uInt' that limits the amount of data that zlib | |
* can handle at once. This type need be no larger than 16 bits (so maximum of | |
* 65535), this define allows us to discover how big it is, but limited by the | |
* maximuum for png_size_t. The value can be overriden in a library build | |
* (pngusr.h, or set it in CPPFLAGS) and it works to set it to a considerably | |
* lower value (e.g. 255 works). A lower value may help memory usage (slightly) | |
* and may even improve performance on some systems (and degrade it on others.) | |
*/ | |
#ifndef ZLIB_IO_MAX | |
# define ZLIB_IO_MAX ((uInt)-1) | |
#endif | |
#ifdef PNG_WRITE_SUPPORTED | |
/* The type of a compression buffer list used by the write code. */ | |
typedef struct png_compression_buffer | |
{ | |
struct png_compression_buffer *next; | |
png_byte output[1]; /* actually zbuf_size */ | |
} png_compression_buffer, *png_compression_bufferp; | |
#define PNG_COMPRESSION_BUFFER_SIZE(pp)\ | |
(offsetof(png_compression_buffer, output) + (pp)->zbuffer_size) | |
#endif | |
/* Colorspace support; structures used in png_struct, png_info and in internal | |
* functions to hold and communicate information about the color space. | |
* | |
* PNG_COLORSPACE_SUPPORTED is only required if the application will perform | |
* colorspace corrections, otherwise all the colorspace information can be | |
* skipped and the size of libpng can be reduced (significantly) by compiling | |
* out the colorspace support. | |
*/ | |
#ifdef PNG_COLORSPACE_SUPPORTED | |
/* The chromaticities of the red, green and blue colorants and the chromaticity | |
* of the corresponding white point (i.e. of rgb(1.0,1.0,1.0)). | |
*/ | |
typedef struct png_xy | |
{ | |
png_fixed_point redx, redy; | |
png_fixed_point greenx, greeny; | |
png_fixed_point bluex, bluey; | |
png_fixed_point whitex, whitey; | |
} png_xy; | |
/* The same data as above but encoded as CIE XYZ values. When this data comes | |
* from chromaticities the sum of the Y values is assumed to be 1.0 | |
*/ | |
typedef struct png_XYZ | |
{ | |
png_fixed_point red_X, red_Y, red_Z; | |
png_fixed_point green_X, green_Y, green_Z; | |
png_fixed_point blue_X, blue_Y, blue_Z; | |
} png_XYZ; | |
#endif /* COLORSPACE */ | |
#if defined(PNG_COLORSPACE_SUPPORTED) || defined(PNG_GAMMA_SUPPORTED) | |
/* A colorspace is all the above plus, potentially, profile information, | |
* however at present libpng does not use the profile internally so it is only | |
* stored in the png_info struct (if iCCP is supported.) The rendering intent | |
* is retained here and is checked. | |
* | |
* The file gamma encoding information is also stored here and gamma correction | |
* is done by libpng, whereas color correction must currently be done by the | |
* application. | |
*/ | |
typedef struct png_colorspace | |
{ | |
#ifdef PNG_GAMMA_SUPPORTED | |
png_fixed_point gamma; /* File gamma */ | |
#endif | |
#ifdef PNG_COLORSPACE_SUPPORTED | |
png_xy end_points_xy; /* End points as chromaticities */ | |
png_XYZ end_points_XYZ; /* End points as CIE XYZ colorant values */ | |
png_uint_16 rendering_intent; /* Rendering intent of a profile */ | |
#endif | |
/* Flags are always defined to simplify the code. */ | |
png_uint_16 flags; /* As defined below */ | |
} png_colorspace, * PNG_RESTRICT png_colorspacerp; | |
typedef const png_colorspace * PNG_RESTRICT png_const_colorspacerp; | |
/* General flags for the 'flags' field */ | |
#define PNG_COLORSPACE_HAVE_GAMMA 0x0001 | |
#define PNG_COLORSPACE_HAVE_ENDPOINTS 0x0002 | |
#define PNG_COLORSPACE_HAVE_INTENT 0x0004 | |
#define PNG_COLORSPACE_FROM_gAMA 0x0008 | |
#define PNG_COLORSPACE_FROM_cHRM 0x0010 | |
#define PNG_COLORSPACE_FROM_sRGB 0x0020 | |
#define PNG_COLORSPACE_ENDPOINTS_MATCH_sRGB 0x0040 | |
#define PNG_COLORSPACE_MATCHES_sRGB 0x0080 /* exact match on profile */ | |
#define PNG_COLORSPACE_INVALID 0x8000 | |
#define PNG_COLORSPACE_CANCEL(flags) (0xffff ^ (flags)) | |
#endif /* COLORSPACE || GAMMA */ | |
struct png_struct_def | |
{ | |
#ifdef PNG_SETJMP_SUPPORTED | |
jmp_buf jmp_buf_local; /* New name in 1.6.0 for jmp_buf in png_struct */ | |
png_longjmp_ptr longjmp_fn;/* setjmp non-local goto function. */ | |
jmp_buf *jmp_buf_ptr; /* passed to longjmp_fn */ | |
size_t jmp_buf_size; /* size of the above, if allocated */ | |
#endif | |
png_error_ptr error_fn; /* function for printing errors and aborting */ | |
#ifdef PNG_WARNINGS_SUPPORTED | |
png_error_ptr warning_fn; /* function for printing warnings */ | |
#endif | |
png_voidp error_ptr; /* user supplied struct for error functions */ | |
png_rw_ptr write_data_fn; /* function for writing output data */ | |
png_rw_ptr read_data_fn; /* function for reading input data */ | |
png_voidp io_ptr; /* ptr to application struct for I/O functions */ | |
#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED | |
png_user_transform_ptr read_user_transform_fn; /* user read transform */ | |
#endif | |
#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED | |
png_user_transform_ptr write_user_transform_fn; /* user write transform */ | |
#endif | |
/* These were added in libpng-1.0.2 */ | |
#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED | |
#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ | |
defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) | |
png_voidp user_transform_ptr; /* user supplied struct for user transform */ | |
png_byte user_transform_depth; /* bit depth of user transformed pixels */ | |
png_byte user_transform_channels; /* channels in user transformed pixels */ | |
#endif | |
#endif | |
png_uint_32 mode; /* tells us where we are in the PNG file */ | |
png_uint_32 flags; /* flags indicating various things to libpng */ | |
png_uint_32 transformations; /* which transformations to perform */ | |
png_uint_32 zowner; /* ID (chunk type) of zstream owner, 0 if none */ | |
z_stream zstream; /* decompression structure */ | |
#ifdef PNG_WRITE_SUPPORTED | |
png_compression_bufferp zbuffer_list; /* Created on demand during write */ | |
uInt zbuffer_size; /* size of the actual buffer */ | |
int zlib_level; /* holds zlib compression level */ | |
int zlib_method; /* holds zlib compression method */ | |
int zlib_window_bits; /* holds zlib compression window bits */ | |
int zlib_mem_level; /* holds zlib compression memory level */ | |
int zlib_strategy; /* holds zlib compression strategy */ | |
#endif | |
/* Added at libpng 1.5.4 */ | |
#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED | |
int zlib_text_level; /* holds zlib compression level */ | |
int zlib_text_method; /* holds zlib compression method */ | |
int zlib_text_window_bits; /* holds zlib compression window bits */ | |
int zlib_text_mem_level; /* holds zlib compression memory level */ | |
int zlib_text_strategy; /* holds zlib compression strategy */ | |
#endif | |
/* End of material added at libpng 1.5.4 */ | |
/* Added at libpng 1.6.0 */ | |
#ifdef PNG_WRITE_SUPPORTED | |
int zlib_set_level; /* Actual values set into the zstream on write */ | |
int zlib_set_method; | |
int zlib_set_window_bits; | |
int zlib_set_mem_level; | |
int zlib_set_strategy; | |
#endif | |
png_uint_32 width; /* width of image in pixels */ | |
png_uint_32 height; /* height of image in pixels */ | |
png_uint_32 num_rows; /* number of rows in current pass */ | |
png_uint_32 usr_width; /* width of row at start of write */ | |
png_size_t rowbytes; /* size of row in bytes */ | |
png_uint_32 iwidth; /* width of current interlaced row in pixels */ | |
png_uint_32 row_number; /* current row in interlace pass */ | |
png_uint_32 chunk_name; /* PNG_CHUNK() id of current chunk */ | |
png_bytep prev_row; /* buffer to save previous (unfiltered) row. | |
* This is a pointer into big_prev_row | |
*/ | |
png_bytep row_buf; /* buffer to save current (unfiltered) row. | |
* This is a pointer into big_row_buf | |
*/ | |
#ifdef PNG_WRITE_SUPPORTED | |
png_bytep sub_row; /* buffer to save "sub" row when filtering */ | |
png_bytep up_row; /* buffer to save "up" row when filtering */ | |
png_bytep avg_row; /* buffer to save "avg" row when filtering */ | |
png_bytep paeth_row; /* buffer to save "Paeth" row when filtering */ | |
#endif | |
png_size_t info_rowbytes; /* Added in 1.5.4: cache of updated row bytes */ | |
png_uint_32 idat_size; /* current IDAT size for read */ | |
png_uint_32 crc; /* current chunk CRC value */ | |
png_colorp palette; /* palette from the input file */ | |
png_uint_16 num_palette; /* number of color entries in palette */ | |
/* Added at libpng-1.5.10 */ | |
#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED | |
int num_palette_max; /* maximum palette index found in IDAT */ | |
#endif | |
png_uint_16 num_trans; /* number of transparency values */ | |
png_byte compression; /* file compression type (always 0) */ | |
png_byte filter; /* file filter type (always 0) */ | |
png_byte interlaced; /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */ | |
png_byte pass; /* current interlace pass (0 - 6) */ | |
png_byte do_filter; /* row filter flags (see PNG_FILTER_ below ) */ | |
png_byte color_type; /* color type of file */ | |
png_byte bit_depth; /* bit depth of file */ | |
png_byte usr_bit_depth; /* bit depth of users row: write only */ | |
png_byte pixel_depth; /* number of bits per pixel */ | |
png_byte channels; /* number of channels in file */ | |
#ifdef PNG_WRITE_SUPPORTED | |
png_byte usr_channels; /* channels at start of write: write only */ | |
#endif | |
png_byte sig_bytes; /* magic bytes read/written from start of file */ | |
png_byte maximum_pixel_depth; | |
/* pixel depth used for the row buffers */ | |
png_byte transformed_pixel_depth; | |
/* pixel depth after read/write transforms */ | |
#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) | |
png_uint_16 filler; /* filler bytes for pixel expansion */ | |
#endif | |
#if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) ||\ | |
defined(PNG_READ_ALPHA_MODE_SUPPORTED) | |
png_byte background_gamma_type; | |
png_fixed_point background_gamma; | |
png_color_16 background; /* background color in screen gamma space */ | |
#ifdef PNG_READ_GAMMA_SUPPORTED | |
png_color_16 background_1; /* background normalized to gamma 1.0 */ | |
#endif | |
#endif /* PNG_bKGD_SUPPORTED */ | |
#ifdef PNG_WRITE_FLUSH_SUPPORTED | |
png_flush_ptr output_flush_fn; /* Function for flushing output */ | |
png_uint_32 flush_dist; /* how many rows apart to flush, 0 - no flush */ | |
png_uint_32 flush_rows; /* number of rows written since last flush */ | |
#endif | |
#ifdef PNG_READ_GAMMA_SUPPORTED | |
int gamma_shift; /* number of "insignificant" bits in 16-bit gamma */ | |
png_fixed_point screen_gamma; /* screen gamma value (display_exponent) */ | |
png_bytep gamma_table; /* gamma table for 8-bit depth files */ | |
png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */ | |
#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \ | |
defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \ | |
defined(PNG_READ_RGB_TO_GRAY_SUPPORTED) | |
png_bytep gamma_from_1; /* converts from 1.0 to screen */ | |
png_bytep gamma_to_1; /* converts from file to 1.0 */ | |
png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */ | |
png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */ | |
#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */ | |
#endif | |
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED) | |
png_color_8 sig_bit; /* significant bits in each available channel */ | |
#endif | |
#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED) | |
png_color_8 shift; /* shift for significant bit tranformation */ | |
#endif | |
#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \ | |
|| defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) | |
png_bytep trans_alpha; /* alpha values for paletted files */ | |
png_color_16 trans_color; /* transparent color for non-paletted files */ | |
#endif | |
png_read_status_ptr read_row_fn; /* called after each row is decoded */ | |
png_write_status_ptr write_row_fn; /* called after each row is encoded */ | |
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED | |
png_progressive_info_ptr info_fn; /* called after header data fully read */ | |
png_progressive_row_ptr row_fn; /* called after a prog. row is decoded */ | |
png_progressive_end_ptr end_fn; /* called after image is complete */ | |
png_bytep save_buffer_ptr; /* current location in save_buffer */ | |
png_bytep save_buffer; /* buffer for previously read data */ | |
png_bytep current_buffer_ptr; /* current location in current_buffer */ | |
png_bytep current_buffer; /* buffer for recently used data */ | |
png_uint_32 push_length; /* size of current input chunk */ | |
png_uint_32 skip_length; /* bytes to skip in input data */ | |
png_size_t save_buffer_size; /* amount of data now in save_buffer */ | |
png_size_t save_buffer_max; /* total size of save_buffer */ | |
png_size_t buffer_size; /* total amount of available input data */ | |
png_size_t current_buffer_size; /* amount of data now in current_buffer */ | |
int process_mode; /* what push library is currently doing */ | |
int cur_palette; /* current push library palette index */ | |
#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ | |
#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__) | |
/* For the Borland special 64K segment handler */ | |
png_bytepp offset_table_ptr; | |
png_bytep offset_table; | |
png_uint_16 offset_table_number; | |
png_uint_16 offset_table_count; | |
png_uint_16 offset_table_count_free; | |
#endif | |
#ifdef PNG_READ_QUANTIZE_SUPPORTED | |
png_bytep palette_lookup; /* lookup table for quantizing */ | |
png_bytep quantize_index; /* index translation for palette files */ | |
#endif | |
#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED | |
png_byte heuristic_method; /* heuristic for row filter selection */ | |
png_byte num_prev_filters; /* number of weights for previous rows */ | |
png_bytep prev_filters; /* filter type(s) of previous row(s) */ | |
png_uint_16p filter_weights; /* weight(s) for previous line(s) */ | |
png_uint_16p inv_filter_weights; /* 1/weight(s) for previous line(s) */ | |
png_uint_16p filter_costs; /* relative filter calculation cost */ | |
png_uint_16p inv_filter_costs; /* 1/relative filter calculation cost */ | |
#endif | |
/* Options */ | |
#ifdef PNG_SET_OPTION_SUPPORTED | |
png_byte options; /* On/off state (up to 4 options) */ | |
#endif | |
#if PNG_LIBPNG_VER < 10700 | |
/* To do: remove this from libpng-1.7 */ | |
#ifdef PNG_TIME_RFC1123_SUPPORTED | |
char time_buffer[29]; /* String to hold RFC 1123 time text */ | |
#endif | |
#endif | |
/* New members added in libpng-1.0.6 */ | |
png_uint_32 free_me; /* flags items libpng is responsible for freeing */ | |
#ifdef PNG_USER_CHUNKS_SUPPORTED | |
png_voidp user_chunk_ptr; | |
#ifdef PNG_READ_USER_CHUNKS_SUPPORTED | |
png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */ | |
#endif | |
#endif | |
#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED | |
int unknown_default; /* As PNG_HANDLE_* */ | |
unsigned int num_chunk_list; /* Number of entries in the list */ | |
png_bytep chunk_list; /* List of png_byte[5]; the textual chunk name | |
* followed by a PNG_HANDLE_* byte */ | |
#endif | |
/* New members added in libpng-1.0.3 */ | |
#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED | |
png_byte rgb_to_gray_status; | |
/* Added in libpng 1.5.5 to record setting of coefficients: */ | |
png_byte rgb_to_gray_coefficients_set; | |
/* These were changed from png_byte in libpng-1.0.6 */ | |
png_uint_16 rgb_to_gray_red_coeff; | |
png_uint_16 rgb_to_gray_green_coeff; | |
/* deleted in 1.5.5: rgb_to_gray_blue_coeff; */ | |
#endif | |
/* New member added in libpng-1.0.4 (renamed in 1.0.9) */ | |
#if defined(PNG_MNG_FEATURES_SUPPORTED) | |
/* Changed from png_byte to png_uint_32 at version 1.2.0 */ | |
png_uint_32 mng_features_permitted; | |
#endif | |
/* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */ | |
#ifdef PNG_MNG_FEATURES_SUPPORTED | |
png_byte filter_type; | |
#endif | |
/* New members added in libpng-1.2.0 */ | |
/* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */ | |
#ifdef PNG_USER_MEM_SUPPORTED | |
png_voidp mem_ptr; /* user supplied struct for mem functions */ | |
png_malloc_ptr malloc_fn; /* function for allocating memory */ | |
png_free_ptr free_fn; /* function for freeing memory */ | |
#endif | |
/* New member added in libpng-1.0.13 and 1.2.0 */ | |
png_bytep big_row_buf; /* buffer to save current (unfiltered) row */ | |
#ifdef PNG_READ_QUANTIZE_SUPPORTED | |
/* The following three members were added at version 1.0.14 and 1.2.4 */ | |
png_bytep quantize_sort; /* working sort array */ | |
png_bytep index_to_palette; /* where the original index currently is | |
in the palette */ | |
png_bytep palette_to_index; /* which original index points to this | |
palette color */ | |
#endif | |
/* New members added in libpng-1.0.16 and 1.2.6 */ | |
png_byte compression_type; | |
#ifdef PNG_USER_LIMITS_SUPPORTED | |
png_uint_32 user_width_max; | |
png_uint_32 user_height_max; | |
/* Added in libpng-1.4.0: Total number of sPLT, text, and unknown | |
* chunks that can be stored (0 means unlimited). | |
*/ | |
png_uint_32 user_chunk_cache_max; | |
/* Total memory that a zTXt, sPLT, iTXt, iCCP, or unknown chunk | |
* can occupy when decompressed. 0 means unlimited. | |
*/ | |
png_alloc_size_t user_chunk_malloc_max; | |
#endif | |
/* New member added in libpng-1.0.25 and 1.2.17 */ | |
#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED | |
/* Temporary storage for unknown chunk that the library doesn't recognize, | |
* used while reading the chunk. | |
*/ | |
png_unknown_chunk unknown_chunk; | |
#endif | |
/* New member added in libpng-1.2.26 */ | |
png_size_t old_big_row_buf_size; | |
#ifdef PNG_READ_SUPPORTED | |
/* New member added in libpng-1.2.30 */ | |
png_bytep read_buffer; /* buffer for reading chunk data */ | |
png_alloc_size_t read_buffer_size; /* current size of the buffer */ | |
#endif | |
#ifdef PNG_SEQUENTIAL_READ_SUPPORTED | |
uInt IDAT_read_size; /* limit on read buffer size for IDAT */ | |
#endif | |
#ifdef PNG_IO_STATE_SUPPORTED | |
/* New member added in libpng-1.4.0 */ | |
png_uint_32 io_state; | |
#endif | |
/* New member added in libpng-1.5.6 */ | |
png_bytep big_prev_row; | |
/* New member added in libpng-1.5.7 */ | |
void (*read_filter[PNG_FILTER_VALUE_LAST-1])(png_row_infop row_info, | |
png_bytep row, png_const_bytep prev_row); | |
#ifdef PNG_READ_SUPPORTED | |
#if defined(PNG_COLORSPACE_SUPPORTED) || defined(PNG_GAMMA_SUPPORTED) | |
png_colorspace colorspace; | |
#endif | |
#endif | |
}; | |
#endif /* PNGSTRUCT_H */ |