diff options
Diffstat (limited to 'png/pngstruct.h')
| -rw-r--r-- | png/pngstruct.h | 112 |
1 files changed, 49 insertions, 63 deletions
diff --git a/png/pngstruct.h b/png/pngstruct.h index e591d94d5..084422bc1 100644 --- a/png/pngstruct.h +++ b/png/pngstruct.h @@ -1,7 +1,6 @@ - -/* pngstruct.h - header file for PNG reference library +/* pngstruct.h - internal structures for libpng * - * Copyright (c) 2018-2022 Cosmin Truta + * Copyright (c) 2018-2025 Cosmin Truta * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson * Copyright (c) 1996-1997 Andreas Dilger * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc. @@ -11,11 +10,9 @@ * 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 PNGPRIV_H +# error This file must not be included by applications; please include <png.h> +#endif #ifndef PNGSTRUCT_H #define PNGSTRUCT_H @@ -70,13 +67,7 @@ typedef struct png_compression_buffer /* 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)). */ @@ -97,48 +88,36 @@ typedef struct png_XYZ 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. +/* Chunk index values as an enum, PNG_INDEX_unknown is also a count of the + * number of chunks. */ -typedef struct png_colorspace +#define PNG_CHUNK(cHNK, i) PNG_INDEX_ ## cHNK = (i), +typedef enum { -#ifdef PNG_GAMMA_SUPPORTED - png_fixed_point gamma; /* File gamma */ -#endif + PNG_KNOWN_CHUNKS + PNG_INDEX_unknown +} png_index; +#undef PNG_CHUNK -#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; +/* Chunk flag values. These are (png_uint_32 values) with exactly one bit set + * and can be combined into a flag set with bitwise 'or'. + * + * TODO: C23: convert these macros to C23 inlines (which are static). + */ +#define png_chunk_flag_from_index(i) (0x80000000U >> (31 - (i))) + /* The flag coresponding to the given png_index enum value. This is defined + * for png_unknown as well (until it reaches the value 32) but this should + * not be relied on. + */ -typedef const png_colorspace * PNG_RESTRICT png_const_colorspacerp; +#define png_file_has_chunk(png_ptr, i)\ + (((png_ptr)->chunks & png_chunk_flag_from_index(i)) != 0) + /* The chunk has been recorded in png_struct */ -/* 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 */ +#define png_file_add_chunk(pnt_ptr, i)\ + ((void)((png_ptr)->chunks |= png_chunk_flag_from_index(i))) + /* Record the chunk in the png_struct */ struct png_struct_def { @@ -210,6 +189,11 @@ struct png_struct_def int zlib_set_strategy; #endif + png_uint_32 chunks; /* PNG_CF_ for every chunk read or (NYI) written */ +# define png_has_chunk(png_ptr, cHNK)\ + png_file_has_chunk(png_ptr, PNG_INDEX_ ## cHNK) + /* Convenience accessor - use this to check for a known chunk by name */ + 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 */ @@ -286,9 +270,16 @@ struct png_struct_def png_uint_32 flush_rows; /* number of rows written since last flush */ #endif +#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED + png_xy chromaticities; /* From mDVC, cICP, [iCCP], sRGB or cHRM */ +#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_fixed_point screen_gamma; /* screen gamma value (display exponent) */ + png_fixed_point file_gamma; /* file gamma value (encoding exponent) */ + png_fixed_point chunk_gamma; /* from cICP, iCCP, sRGB or gAMA */ + png_fixed_point default_gamma;/* from png_set_alpha_mode */ png_bytep gamma_table; /* gamma table for 8-bit depth files */ png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */ @@ -300,7 +291,7 @@ struct png_struct_def 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 +#endif /* READ_GAMMA */ #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED) png_color_8 sig_bit; /* significant bits in each available channel */ @@ -350,8 +341,8 @@ struct png_struct_def /* 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 +#endif /* TIME_RFC1123 */ +#endif /* LIBPNG_VER < 10700 */ /* New members added in libpng-1.0.6 */ @@ -361,8 +352,8 @@ struct png_struct_def 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 +#endif /* READ_USER_CHUNKS */ +#endif /* USER_CHUNKS */ #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED int unknown_default; /* As PNG_HANDLE_* */ @@ -384,7 +375,8 @@ struct png_struct_def /* New member added in libpng-1.6.36 */ #if defined(PNG_READ_EXPAND_SUPPORTED) && \ - defined(PNG_ARM_NEON_IMPLEMENTATION) + (defined(PNG_ARM_NEON_IMPLEMENTATION) || \ + defined(PNG_RISCV_RVV_IMPLEMENTATION)) png_bytep riffled_palette; /* buffer for accelerated palette expansion */ #endif @@ -469,11 +461,5 @@ struct png_struct_def /* 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 */ |