X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/4946a942d77cf51e00aa56404756e124d7c11411..6e48287c6a710b80cbac01c225a6d9cd28a884d2:/src/png/png.h diff --git a/src/png/png.h b/src/png/png.h index 365c80b392..0b5053fcff 100644 --- a/src/png/png.h +++ b/src/png/png.h @@ -1,23 +1,26 @@ + /* png.h - header file for PNG reference library * - * libpng version 1.2.4 - July 8, 2002 - * Copyright (c) 1998-2002 Glenn Randers-Pehrson + * libpng version 1.6.2 - April 25, 2013 + * 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.) * + * This code is released under the libpng license (See LICENSE, below) + * * Authors and maintainers: - * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat - * libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger - * libpng versions 0.97, January 1998, through 1.2.4 - July 8, 2002: Glenn - * See also "Contributing Authors", below. + * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat + * libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger + * libpng versions 0.97, January 1998, through 1.6.2 - April 25, 2013: Glenn + * See also "Contributing Authors", below. * * Note about libpng version numbers: * - * Due to various miscommunications, unforeseen code incompatibilities - * and occasional factors outside the authors' control, version numbering - * on the library has not always been consistent and straightforward. - * The following table summarizes matters since version 0.89c, which was - * the first widely used release: + * Due to various miscommunications, unforeseen code incompatibilities + * and occasional factors outside the authors' control, version numbering + * on the library has not always been consistent and straightforward. + * The following table summarizes matters since version 0.89c, which was + * the first widely used release: * * source png.h png.h shared-lib * version string int version @@ -93,27 +96,106 @@ * 1.2.4rc1 13 10204 12.so.0.1.2.4rc1 * 1.0.14 10 10014 10.so.0.1.0.14 * 1.2.4 13 10204 12.so.0.1.2.4 + * 1.2.5beta1-2 13 10205 12.so.0.1.2.5beta1-2 + * 1.0.15rc1-3 10 10015 10.so.0.1.0.15rc1-3 + * 1.2.5rc1-3 13 10205 12.so.0.1.2.5rc1-3 + * 1.0.15 10 10015 10.so.0.1.0.15 + * 1.2.5 13 10205 12.so.0.1.2.5 + * 1.2.6beta1-4 13 10206 12.so.0.1.2.6beta1-4 + * 1.0.16 10 10016 10.so.0.1.0.16 + * 1.2.6 13 10206 12.so.0.1.2.6 + * 1.2.7beta1-2 13 10207 12.so.0.1.2.7beta1-2 + * 1.0.17rc1 10 10017 12.so.0.1.0.17rc1 + * 1.2.7rc1 13 10207 12.so.0.1.2.7rc1 + * 1.0.17 10 10017 12.so.0.1.0.17 + * 1.2.7 13 10207 12.so.0.1.2.7 + * 1.2.8beta1-5 13 10208 12.so.0.1.2.8beta1-5 + * 1.0.18rc1-5 10 10018 12.so.0.1.0.18rc1-5 + * 1.2.8rc1-5 13 10208 12.so.0.1.2.8rc1-5 + * 1.0.18 10 10018 12.so.0.1.0.18 + * 1.2.8 13 10208 12.so.0.1.2.8 + * 1.2.9beta1-3 13 10209 12.so.0.1.2.9beta1-3 + * 1.2.9beta4-11 13 10209 12.so.0.9[.0] + * 1.2.9rc1 13 10209 12.so.0.9[.0] + * 1.2.9 13 10209 12.so.0.9[.0] + * 1.2.10beta1-7 13 10210 12.so.0.10[.0] + * 1.2.10rc1-2 13 10210 12.so.0.10[.0] + * 1.2.10 13 10210 12.so.0.10[.0] + * 1.4.0beta1-5 14 10400 14.so.0.0[.0] + * 1.2.11beta1-4 13 10211 12.so.0.11[.0] + * 1.4.0beta7-8 14 10400 14.so.0.0[.0] + * 1.2.11 13 10211 12.so.0.11[.0] + * 1.2.12 13 10212 12.so.0.12[.0] + * 1.4.0beta9-14 14 10400 14.so.0.0[.0] + * 1.2.13 13 10213 12.so.0.13[.0] + * 1.4.0beta15-36 14 10400 14.so.0.0[.0] + * 1.4.0beta37-87 14 10400 14.so.14.0[.0] + * 1.4.0rc01 14 10400 14.so.14.0[.0] + * 1.4.0beta88-109 14 10400 14.so.14.0[.0] + * 1.4.0rc02-08 14 10400 14.so.14.0[.0] + * 1.4.0 14 10400 14.so.14.0[.0] + * 1.4.1beta01-03 14 10401 14.so.14.1[.0] + * 1.4.1rc01 14 10401 14.so.14.1[.0] + * 1.4.1beta04-12 14 10401 14.so.14.1[.0] + * 1.4.1 14 10401 14.so.14.1[.0] + * 1.4.2 14 10402 14.so.14.2[.0] + * 1.4.3 14 10403 14.so.14.3[.0] + * 1.4.4 14 10404 14.so.14.4[.0] + * 1.5.0beta01-58 15 10500 15.so.15.0[.0] + * 1.5.0rc01-07 15 10500 15.so.15.0[.0] + * 1.5.0 15 10500 15.so.15.0[.0] + * 1.5.1beta01-11 15 10501 15.so.15.1[.0] + * 1.5.1rc01-02 15 10501 15.so.15.1[.0] + * 1.5.1 15 10501 15.so.15.1[.0] + * 1.5.2beta01-03 15 10502 15.so.15.2[.0] + * 1.5.2rc01-03 15 10502 15.so.15.2[.0] + * 1.5.2 15 10502 15.so.15.2[.0] + * 1.5.3beta01-10 15 10503 15.so.15.3[.0] + * 1.5.3rc01-02 15 10503 15.so.15.3[.0] + * 1.5.3beta11 15 10503 15.so.15.3[.0] + * 1.5.3 [omitted] + * 1.5.4beta01-08 15 10504 15.so.15.4[.0] + * 1.5.4rc01 15 10504 15.so.15.4[.0] + * 1.5.4 15 10504 15.so.15.4[.0] + * 1.5.5beta01-08 15 10505 15.so.15.5[.0] + * 1.5.5rc01 15 10505 15.so.15.5[.0] + * 1.5.5 15 10505 15.so.15.5[.0] + * 1.5.6beta01-07 15 10506 15.so.15.6[.0] + * 1.5.6rc01-03 15 10506 15.so.15.6[.0] + * 1.5.6 15 10506 15.so.15.6[.0] + * 1.5.7beta01-05 15 10507 15.so.15.7[.0] + * 1.5.7rc01-03 15 10507 15.so.15.7[.0] + * 1.5.7 15 10507 15.so.15.7[.0] + * 1.6.0beta01-40 16 10600 16.so.16.0[.0] + * 1.6.0rc01-08 16 10600 16.so.16.0[.0] + * 1.6.0 16 10600 16.so.16.0[.0] + * 1.6.1beta01-09 16 10601 16.so.16.1[.0] + * 1.6.1rc01 16 10601 16.so.16.1[.0] + * 1.6.1 16 10601 16.so.16.1[.0] + * 1.6.2beta01 16 10602 16.so.16.2[.0] + * 1.6.2rc01-06 16 10602 16.so.16.2[.0] + * 1.6.2 16 10602 16.so.16.2[.0] * - * Henceforth the source version will match the shared-library major - * and minor numbers; the shared-library major version number will be - * used for changes in backward compatibility, as it is intended. The - * PNG_LIBPNG_VER macro, which is not used within libpng but is available - * for applications, is an unsigned integer of the form xyyzz corresponding - * to the source version x.y.z (leading zeros in y and z). Beta versions - * were given the previous public release number plus a letter, until - * version 1.0.6j; from then on they were given the upcoming public - * release number plus "betaNN" or "rcN". + * Henceforth the source version will match the shared-library major + * and minor numbers; the shared-library major version number will be + * used for changes in backward compatibility, as it is intended. The + * PNG_LIBPNG_VER macro, which is not used within libpng but is available + * for applications, is an unsigned integer of the form xyyzz corresponding + * to the source version x.y.z (leading zeros in y and z). Beta versions + * were given the previous public release number plus a letter, until + * version 1.0.6j; from then on they were given the upcoming public + * release number plus "betaNN" or "rcNN". * - * Binary incompatibility exists only when applications make direct access - * to the info_ptr or png_ptr members through png.h, and the compiled - * application is loaded with a different version of the library. + * Binary incompatibility exists only when applications make direct access + * to the info_ptr or png_ptr members through png.h, and the compiled + * application is loaded with a different version of the library. * - * DLLNUM will change each time there are forward or backward changes - * in binary compatibility (e.g., when a new feature is added). + * DLLNUM will change each time there are forward or backward changes + * in binary compatibility (e.g., when a new feature is added). * - * See libpng.txt or libpng.3 for more information. The PNG specification - * is available as RFC 2083 - * and as a W3C Recommendation + * See libpng-manual.txt or libpng.3 for more information. The PNG + * specification is available as a W3C Recommendation and as an ISO + * Specification, , and the application + * must include this before png.h to obtain the definition of jmp_buf. The + * function is required to be PNG_NORETURN, but this is not checked. If the + * function does return the application will crash via an abort() or similar + * system level call. + * + * If you get a warning here while building the library you may need to make + * changes to ensure that pnglibconf.h records the calling convention used by + * your compiler. This may be very difficult - try using a different compiler + * to build the library! + */ +PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef); #endif /* Transform masks for the high-level interface */ @@ -986,618 +941,663 @@ typedef void (PNGAPI *png_unknown_chunk_ptr) PNGARG((png_structp)); #define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */ #define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */ #define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */ -#define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* WRITE only */ +#define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* write only */ +/* Added to libpng-1.2.34 */ +#define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER +#define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */ +/* Added to libpng-1.4.0 */ +#define PNG_TRANSFORM_GRAY_TO_RGB 0x2000 /* read only */ +/* Added to libpng-1.5.4 */ +#define PNG_TRANSFORM_EXPAND_16 0x4000 /* read only */ +#define PNG_TRANSFORM_SCALE_16 0x8000 /* read only */ /* Flags for MNG supported features */ #define PNG_FLAG_MNG_EMPTY_PLTE 0x01 #define PNG_FLAG_MNG_FILTER_64 0x04 #define PNG_ALL_MNG_FEATURES 0x05 -typedef png_voidp (*png_malloc_ptr) PNGARG((png_structp, png_size_t)); -typedef void (*png_free_ptr) PNGARG((png_structp, png_voidp)); - -/* 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, except to store - * the jmp_buf. - */ - -struct png_struct_def -{ -#ifdef PNG_SETJMP_SUPPORTED - jmp_buf jmpbuf; /* used in png_error */ -#endif - png_error_ptr error_fn; /* function for printing errors and aborting */ - png_error_ptr warning_fn; /* function for printing warnings */ - 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 */ - -#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) - png_user_transform_ptr read_user_transform_fn; /* user read transform */ -#endif - -#if defined(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 */ -#if defined(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 */ - - z_stream zstream; /* pointer to decompression structure (below) */ - png_bytep zbuf; /* buffer for zlib */ - png_size_t zbuf_size; /* size of zbuf */ - 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 */ - - 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_uint_32 rowbytes; /* size of row in bytes */ - png_uint_32 irowbytes; /* size of current interlaced 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_bytep prev_row; /* buffer to save previous (unfiltered) row */ - png_bytep row_buf; /* buffer to save current (unfiltered) row */ - 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 */ - png_row_info row_info; /* used for transformation routines */ - - 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 */ - png_uint_16 num_trans; /* number of transparency values */ - png_byte chunk_name[5]; /* null-terminated name of current chunk */ - 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 */ - png_byte pixel_depth; /* number of bits per pixel */ - png_byte channels; /* number of channels in file */ - png_byte usr_channels; /* channels at start of write */ - png_byte sig_bytes; /* magic bytes read/written from start of file */ - -#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) -#ifdef PNG_LEGACY_SUPPORTED - png_byte filler; /* filler byte for pixel expansion */ -#else - png_uint_16 filler; /* filler bytes for pixel expansion */ -#endif -#endif - -#if defined(PNG_bKGD_SUPPORTED) - png_byte background_gamma_type; -# ifdef PNG_FLOATING_POINT_SUPPORTED - float background_gamma; -# endif - png_color_16 background; /* background color in screen gamma space */ -#if defined(PNG_READ_GAMMA_SUPPORTED) - png_color_16 background_1; /* background normalized to gamma 1.0 */ -#endif -#endif /* PNG_bKGD_SUPPORTED */ - -#if defined(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 - -#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) - int gamma_shift; /* number of "insignificant" bits 16-bit gamma */ -#ifdef PNG_FLOATING_POINT_SUPPORTED - float gamma; /* file gamma value */ - float screen_gamma; /* screen gamma value (display_exponent) */ -#endif -#endif - -#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) - png_bytep gamma_table; /* gamma table for 8-bit depth files */ - 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_table; /* gamma table for 16-bit depth files */ - 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 - -#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; /* transparency values for paletted files */ - png_color_16 trans_values; /* transparency values 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 each 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 */ - -# if defined(PNG_TEXT_SUPPORTED) - png_size_t current_text_size; /* current size of text input data */ - png_size_t current_text_left; /* how much text left to read in input */ - png_charp current_text; /* current text chunk buffer */ - png_charp current_text_ptr; /* current location in current_text */ -# endif /* PNG_PROGRESSIVE_READ_SUPPORTED && PNG_TEXT_SUPPORTED */ - -#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 - -#if defined(PNG_READ_DITHER_SUPPORTED) - png_bytep palette_lookup; /* lookup table for dithering */ - png_bytep dither_index; /* index translation for palette files */ -#endif - -#if defined(PNG_READ_DITHER_SUPPORTED) || defined(PNG_hIST_SUPPORTED) - png_uint_16p hist; /* histogram */ -#endif - -#if defined(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 - -#if defined(PNG_TIME_RFC1123_SUPPORTED) - png_charp time_buffer; /* String to hold RFC 1123 time text */ -#endif - -/* New members added in libpng-1.0.6 */ - -#ifdef PNG_FREE_ME_SUPPORTED - png_uint_32 free_me; /* flags items libpng is responsible for freeing */ -#endif - -#if defined(PNG_USER_CHUNKS_SUPPORTED) - png_voidp user_chunk_ptr; - png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */ -#endif - -#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) - int num_chunk_list; - png_bytep chunk_list; -#endif - -/* New members added in libpng-1.0.3 */ -#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED) - png_byte rgb_to_gray_status; - /* 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; - png_uint_16 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) || \ - defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \ - defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED) -/* changed from png_byte to png_uint_32 at version 1.2.0 */ -#ifdef PNG_1_0_X - png_byte mng_features_permitted; -#else - png_uint_32 mng_features_permitted; -#endif /* PNG_1_0_X */ -#endif - -/* New member added in libpng-1.0.7 */ -#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) - png_fixed_point int_gamma; -#endif - -/* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */ -#if defined(PNG_MNG_FEATURES_SUPPORTED) - png_byte filter_type; -#endif - -#if defined(PNG_1_0_X) || (defined(PNG_DEBUG) && defined(PNG_USE_PNGGCCRD)) -/* New member added in libpng-1.0.10, ifdef'ed out in 1.2.0 */ - png_uint_32 row_buf_size; -#endif - -/* New members added in libpng-1.2.0 */ -#if !defined(PNG_1_0_X) && defined(PNG_ASSEMBLER_CODE_SUPPORTED) - png_byte mmx_bitdepth_threshold; - png_uint_32 mmx_rowbytes_threshold; - png_uint_32 asm_flags; -#endif - -/* 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 */ - -#if defined(PNG_READ_DITHER_SUPPORTED) -/* The following three members were added at version 1.0.14 and 1.2.4 */ - png_bytep dither_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 - -}; - - -/* This prevents a compiler error in png.c if png.c and png.h are both at - version 1.2.4 +/* NOTE: prior to 1.5 these functions had no 'API' style declaration, + * this allowed the zlib default functions to be used on Windows + * platforms. In 1.5 the zlib default malloc (which just calls malloc and + * ignores the first argument) should be completely compatible with the + * following. */ -typedef png_structp version_1_2_4; - -typedef png_struct FAR * FAR * png_structpp; +typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp, + png_alloc_size_t)); +typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp)); -/* Here are the function definitions most commonly used. This is not - * the place to find out how to use libpng. See libpng.txt for the +/* Section 3: exported functions + * Here are the function definitions most commonly used. This is not + * the place to find out how to use libpng. See libpng-manual.txt for the * full explanation, see example.c for the summary. This just provides * a simple one line description of the use of each function. + * + * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in + * pngconf.h and in the *.dfn files in the scripts directory. + * + * PNG_EXPORT(ordinal, type, name, (args)); + * + * ordinal: ordinal that is used while building + * *.def files. The ordinal value is only + * relevant when preprocessing png.h with + * the *.dfn files for building symbol table + * entries, and are removed by pngconf.h. + * type: return type of the function + * name: function name + * args: function arguments, with types + * + * When we wish to append attributes to a function prototype we use + * the PNG_EXPORTA() macro instead. + * + * PNG_EXPORTA(ordinal, type, name, (args), attributes); + * + * ordinal, type, name, and args: same as in PNG_EXPORT(). + * attributes: function attributes */ /* Returns the version number of the library */ -extern PNG_EXPORT(png_uint_32,png_access_version_number) PNGARG((void)); +PNG_EXPORT(1, png_uint_32, png_access_version_number, (void)); /* Tell lib we have already handled the first magic bytes. * Handling more than 8 bytes from the beginning of the file is an error. */ -extern PNG_EXPORT(void,png_set_sig_bytes) PNGARG((png_structp png_ptr, - int num_bytes)); +PNG_EXPORT(2, void, png_set_sig_bytes, (png_structrp png_ptr, int num_bytes)); /* Check sig[start] through sig[start + num_to_check - 1] to see if it's a * PNG file. Returns zero if the supplied bytes match the 8-byte PNG * signature, and non-zero otherwise. Having num_to_check == 0 or * start > 7 will always fail (ie return non-zero). */ -extern PNG_EXPORT(int,png_sig_cmp) PNGARG((png_bytep sig, png_size_t start, - png_size_t num_to_check)); +PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, png_size_t start, + png_size_t num_to_check)); /* Simple signature checking function. This is the same as calling * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n). */ -extern PNG_EXPORT(int,png_check_sig) PNGARG((png_bytep sig, int num)); +#define png_check_sig(sig, n) !png_sig_cmp((sig), 0, (n)) /* Allocate and initialize png_ptr struct for reading, and any other memory. */ -extern PNG_EXPORT(png_structp,png_create_read_struct) - PNGARG((png_const_charp user_png_ver, png_voidp error_ptr, - png_error_ptr error_fn, png_error_ptr warn_fn)); +PNG_EXPORTA(4, png_structp, png_create_read_struct, + (png_const_charp user_png_ver, png_voidp error_ptr, + png_error_ptr error_fn, png_error_ptr warn_fn), + PNG_ALLOCATED); /* Allocate and initialize png_ptr struct for writing, and any other memory */ -extern PNG_EXPORT(png_structp,png_create_write_struct) - PNGARG((png_const_charp user_png_ver, png_voidp error_ptr, - png_error_ptr error_fn, png_error_ptr warn_fn)); +PNG_EXPORTA(5, png_structp, png_create_write_struct, + (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, + png_error_ptr warn_fn), + PNG_ALLOCATED); -extern PNG_EXPORT(png_uint_32,png_get_compression_buffer_size) - PNGARG((png_structp png_ptr)); +PNG_EXPORT(6, png_size_t, png_get_compression_buffer_size, + (png_const_structrp png_ptr)); -extern PNG_EXPORT(void,png_set_compression_buffer_size) - PNGARG((png_structp png_ptr, png_uint_32 size)); +PNG_EXPORT(7, void, png_set_compression_buffer_size, (png_structrp png_ptr, + png_size_t size)); + +/* Moved from pngconf.h in 1.4.0 and modified to ensure setjmp/longjmp + * match up. + */ +#ifdef PNG_SETJMP_SUPPORTED +/* This function returns the jmp_buf built in to *png_ptr. It must be + * supplied with an appropriate 'longjmp' function to use on that jmp_buf + * unless the default error function is overridden in which case NULL is + * acceptable. The size of the jmp_buf is checked against the actual size + * allocated by the library - the call will return NULL on a mismatch + * indicating an ABI mismatch. + */ +PNG_EXPORT(8, jmp_buf*, png_set_longjmp_fn, (png_structrp png_ptr, + png_longjmp_ptr longjmp_fn, size_t jmp_buf_size)); +# define png_jmpbuf(png_ptr) \ + (*png_set_longjmp_fn((png_ptr), longjmp, (sizeof (jmp_buf)))) +#else +# define png_jmpbuf(png_ptr) \ + (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP) +#endif +/* This function should be used by libpng applications in place of + * longjmp(png_ptr->jmpbuf, val). If longjmp_fn() has been set, it + * will use it; otherwise it will call PNG_ABORT(). This function was + * added in libpng-1.5.0. + */ +PNG_EXPORTA(9, void, png_longjmp, (png_const_structrp png_ptr, int val), + PNG_NORETURN); +#ifdef PNG_READ_SUPPORTED /* Reset the compression stream */ -extern PNG_EXPORT(int,png_reset_zstream) PNGARG((png_structp png_ptr)); +PNG_EXPORTA(10, int, png_reset_zstream, (png_structrp png_ptr), PNG_DEPRECATED); +#endif /* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */ #ifdef PNG_USER_MEM_SUPPORTED -extern PNG_EXPORT(png_structp,png_create_read_struct_2) - PNGARG((png_const_charp user_png_ver, png_voidp error_ptr, - png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr, - png_malloc_ptr malloc_fn, png_free_ptr free_fn)); -extern PNG_EXPORT(png_structp,png_create_write_struct_2) - PNGARG((png_const_charp user_png_ver, png_voidp error_ptr, - png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr, - png_malloc_ptr malloc_fn, png_free_ptr free_fn)); +PNG_EXPORTA(11, png_structp, png_create_read_struct_2, + (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, + png_error_ptr warn_fn, + png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), + PNG_ALLOCATED); +PNG_EXPORTA(12, png_structp, png_create_write_struct_2, + (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, + png_error_ptr warn_fn, + png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), + PNG_ALLOCATED); #endif +/* Write the PNG file signature. */ +PNG_EXPORT(13, void, png_write_sig, (png_structrp png_ptr)); + /* Write a PNG chunk - size, type, (optional) data, CRC. */ -extern PNG_EXPORT(void,png_write_chunk) PNGARG((png_structp png_ptr, - png_bytep chunk_name, png_bytep data, png_size_t length)); +PNG_EXPORT(14, void, png_write_chunk, (png_structrp png_ptr, png_const_bytep + chunk_name, png_const_bytep data, png_size_t length)); /* Write the start of a PNG chunk - length and chunk name. */ -extern PNG_EXPORT(void,png_write_chunk_start) PNGARG((png_structp png_ptr, - png_bytep chunk_name, png_uint_32 length)); +PNG_EXPORT(15, void, png_write_chunk_start, (png_structrp png_ptr, + png_const_bytep chunk_name, png_uint_32 length)); /* Write the data of a PNG chunk started with png_write_chunk_start(). */ -extern PNG_EXPORT(void,png_write_chunk_data) PNGARG((png_structp png_ptr, - png_bytep data, png_size_t length)); +PNG_EXPORT(16, void, png_write_chunk_data, (png_structrp png_ptr, + png_const_bytep data, png_size_t length)); /* Finish a chunk started with png_write_chunk_start() (includes CRC). */ -extern PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr)); +PNG_EXPORT(17, void, png_write_chunk_end, (png_structrp png_ptr)); /* Allocate and initialize the info structure */ -extern PNG_EXPORT(png_infop,png_create_info_struct) - PNGARG((png_structp png_ptr)); +PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_const_structrp png_ptr), + PNG_ALLOCATED); -/* Initialize the info structure (old interface - DEPRECATED) */ -extern PNG_EXPORT(void,png_info_init) PNGARG((png_infop info_ptr)); -#undef png_info_init -#define png_info_init(info_ptr) png_info_init_3(&info_ptr, sizeof(png_info)); -extern PNG_EXPORT(void,png_info_init_3) PNGARG((png_infopp info_ptr, - png_size_t png_info_struct_size)); +/* DEPRECATED: this function allowed init structures to be created using the + * default allocation method (typically malloc). Use is deprecated in 1.6.0 and + * the API will be removed in the future. + */ +PNG_EXPORTA(19, void, png_info_init_3, (png_infopp info_ptr, + png_size_t png_info_struct_size), PNG_DEPRECATED); /* Writes all the PNG information before the image. */ -extern PNG_EXPORT(void,png_write_info_before_PLTE) PNGARG((png_structp png_ptr, - png_infop info_ptr)); -extern PNG_EXPORT(void,png_write_info) PNGARG((png_structp png_ptr, - png_infop info_ptr)); - -/* read the information before the actual image data. */ -extern PNG_EXPORT(void,png_read_info) PNGARG((png_structp png_ptr, - png_infop info_ptr)); - -#if defined(PNG_TIME_RFC1123_SUPPORTED) -extern PNG_EXPORT(png_charp,png_convert_to_rfc1123) - PNGARG((png_structp png_ptr, png_timep ptime)); -#endif - -#if !defined(_WIN32_WCE) -/* "time.h" functions are not supported on WindowsCE */ -#if defined(PNG_WRITE_tIME_SUPPORTED) -/* convert from a struct tm to png_time */ -extern PNG_EXPORT(void,png_convert_from_struct_tm) PNGARG((png_timep ptime, - struct tm FAR * ttime)); - -/* convert from time_t to png_time. Uses gmtime() */ -extern PNG_EXPORT(void,png_convert_from_time_t) PNGARG((png_timep ptime, - time_t ttime)); -#endif /* PNG_WRITE_tIME_SUPPORTED */ -#endif /* _WIN32_WCE */ - -#if defined(PNG_READ_EXPAND_SUPPORTED) +PNG_EXPORT(20, void, png_write_info_before_PLTE, + (png_structrp png_ptr, png_const_inforp info_ptr)); +PNG_EXPORT(21, void, png_write_info, + (png_structrp png_ptr, png_const_inforp info_ptr)); + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read the information before the actual image data. */ +PNG_EXPORT(22, void, png_read_info, + (png_structrp png_ptr, png_inforp info_ptr)); +#endif + +#ifdef PNG_TIME_RFC1123_SUPPORTED + /* Convert to a US string format: there is no localization support in this + * routine. The original implementation used a 29 character buffer in + * png_struct, this will be removed in future versions. + */ +#if PNG_LIBPNG_VER < 10700 +/* To do: remove this from libpng17 (and from libpng17/png.c and pngstruct.h) */ +PNG_EXPORTA(23, png_const_charp, png_convert_to_rfc1123, (png_structrp png_ptr, + png_const_timep ptime),PNG_DEPRECATED); +#endif +PNG_EXPORT(241, int, png_convert_to_rfc1123_buffer, (char out[29], + png_const_timep ptime)); +#endif + +#ifdef PNG_CONVERT_tIME_SUPPORTED +/* Convert from a struct tm to png_time */ +PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime, + const struct tm * ttime)); + +/* Convert from time_t to png_time. Uses gmtime() */ +PNG_EXPORT(25, void, png_convert_from_time_t, (png_timep ptime, time_t ttime)); +#endif /* PNG_CONVERT_tIME_SUPPORTED */ + +#ifdef PNG_READ_EXPAND_SUPPORTED /* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */ -extern PNG_EXPORT(void,png_set_expand) PNGARG((png_structp png_ptr)); -extern PNG_EXPORT(void,png_set_gray_1_2_4_to_8) PNGARG((png_structp png_ptr)); -extern PNG_EXPORT(void,png_set_palette_to_rgb) PNGARG((png_structp png_ptr)); -extern PNG_EXPORT(void,png_set_tRNS_to_alpha) PNGARG((png_structp png_ptr)); +PNG_EXPORT(26, void, png_set_expand, (png_structrp png_ptr)); +PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structrp png_ptr)); +PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structrp png_ptr)); +PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structrp png_ptr)); +#endif + +#ifdef PNG_READ_EXPAND_16_SUPPORTED +/* Expand to 16-bit channels, forces conversion of palette to RGB and expansion + * of a tRNS chunk if present. + */ +PNG_EXPORT(221, void, png_set_expand_16, (png_structrp png_ptr)); #endif #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) /* Use blue, green, red order for pixels. */ -extern PNG_EXPORT(void,png_set_bgr) PNGARG((png_structp png_ptr)); +PNG_EXPORT(30, void, png_set_bgr, (png_structrp png_ptr)); #endif -#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED) +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED /* Expand the grayscale to 24-bit RGB if necessary. */ -extern PNG_EXPORT(void,png_set_gray_to_rgb) PNGARG((png_structp png_ptr)); +PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structrp png_ptr)); #endif -#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED) +#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED /* Reduce RGB to grayscale. */ -#ifdef PNG_FLOATING_POINT_SUPPORTED -extern PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr, - int error_action, double red, double green )); +#define PNG_ERROR_ACTION_NONE 1 +#define PNG_ERROR_ACTION_WARN 2 +#define PNG_ERROR_ACTION_ERROR 3 +#define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/ + +PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structrp png_ptr, + int error_action, double red, double green)) +PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structrp png_ptr, + int error_action, png_fixed_point red, png_fixed_point green)) + +PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structrp + png_ptr)); +#endif + +#ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED +PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth, + png_colorp palette)); #endif -extern PNG_EXPORT(void,png_set_rgb_to_gray_fixed) PNGARG((png_structp png_ptr, - int error_action, png_fixed_point red, png_fixed_point green )); -extern PNG_EXPORT(png_byte,png_get_rgb_to_gray_status) PNGARG((png_structp - png_ptr)); + +#ifdef PNG_READ_ALPHA_MODE_SUPPORTED +/* How the alpha channel is interpreted - this affects how the color channels of + * a PNG file are returned when an alpha channel, or tRNS chunk in a palette + * file, is present. + * + * This has no effect on the way pixels are written into a PNG output + * datastream. The color samples in a PNG datastream are never premultiplied + * with the alpha samples. + * + * The default is to return data according to the PNG specification: the alpha + * channel is a linear measure of the contribution of the pixel to the + * corresponding composited pixel. The gamma encoded color channels must be + * scaled according to the contribution and to do this it is necessary to undo + * the encoding, scale the color values, perform the composition and reencode + * the values. This is the 'PNG' mode. + * + * The alternative is to 'associate' the alpha with the color information by + * storing color channel values that have been scaled by the alpha. The + * advantage is that the color channels can be resampled (the image can be + * scaled) in this form. The disadvantage is that normal practice is to store + * linear, not (gamma) encoded, values and this requires 16-bit channels for + * still images rather than the 8-bit channels that are just about sufficient if + * gamma encoding is used. In addition all non-transparent pixel values, + * including completely opaque ones, must be gamma encoded to produce the final + * image. This is the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' mode (the + * latter being the two common names for associated alpha color channels.) + * + * Since it is not necessary to perform arithmetic on opaque color values so + * long as they are not to be resampled and are in the final color space it is + * possible to optimize the handling of alpha by storing the opaque pixels in + * the PNG format (adjusted for the output color space) while storing partially + * opaque pixels in the standard, linear, format. The accuracy required for + * standard alpha composition is relatively low, because the pixels are + * isolated, therefore typically the accuracy loss in storing 8-bit linear + * values is acceptable. (This is not true if the alpha channel is used to + * simulate transparency over large areas - use 16 bits or the PNG mode in + * this case!) This is the 'OPTIMIZED' mode. For this mode a pixel is + * treated as opaque only if the alpha value is equal to the maximum value. + * + * The final choice is to gamma encode the alpha channel as well. This is + * broken because, in practice, no implementation that uses this choice + * correctly undoes the encoding before handling alpha composition. Use this + * choice only if other serious errors in the software or hardware you use + * mandate it; the typical serious error is for dark halos to appear around + * opaque areas of the composited PNG image because of arithmetic overflow. + * + * The API function png_set_alpha_mode specifies which of these choices to use + * with an enumerated 'mode' value and the gamma of the required output: + */ +#define PNG_ALPHA_PNG 0 /* according to the PNG standard */ +#define PNG_ALPHA_STANDARD 1 /* according to Porter/Duff */ +#define PNG_ALPHA_ASSOCIATED 1 /* as above; this is the normal practice */ +#define PNG_ALPHA_PREMULTIPLIED 1 /* as above */ +#define PNG_ALPHA_OPTIMIZED 2 /* 'PNG' for opaque pixels, else 'STANDARD' */ +#define PNG_ALPHA_BROKEN 3 /* the alpha channel is gamma encoded */ + +PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structrp png_ptr, int mode, + double output_gamma)) +PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structrp png_ptr, + int mode, png_fixed_point output_gamma)) +#endif + +#if defined(PNG_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED) +/* The output_gamma value is a screen gamma in libpng terminology: it expresses + * how to decode the output values, not how they are encoded. The values used + * correspond to the normal numbers used to describe the overall gamma of a + * computer display system; for example 2.2 for an sRGB conformant system. The + * values are scaled by 100000 in the _fixed version of the API (so 220000 for + * sRGB.) + * + * The inverse of the value is always used to provide a default for the PNG file + * encoding if it has no gAMA chunk and if png_set_gamma() has not been called + * to override the PNG gamma information. + * + * When the ALPHA_OPTIMIZED mode is selected the output gamma is used to encode + * opaque pixels however pixels with lower alpha values are not encoded, + * regardless of the output gamma setting. + * + * When the standard Porter Duff handling is requested with mode 1 the output + * encoding is set to be linear and the output_gamma value is only relevant + * as a default for input data that has no gamma information. The linear output + * encoding will be overridden if png_set_gamma() is called - the results may be + * highly unexpected! + * + * The following numbers are derived from the sRGB standard and the research + * behind it. sRGB is defined to be approximated by a PNG gAMA chunk value of + * 0.45455 (1/2.2) for PNG. The value implicitly includes any viewing + * correction required to take account of any differences in the color + * environment of the original scene and the intended display environment; the + * value expresses how to *decode* the image for display, not how the original + * data was *encoded*. + * + * sRGB provides a peg for the PNG standard by defining a viewing environment. + * sRGB itself, and earlier TV standards, actually use a more complex transform + * (a linear portion then a gamma 2.4 power law) than PNG can express. (PNG is + * limited to simple power laws.) By saying that an image for direct display on + * an sRGB conformant system should be stored with a gAMA chunk value of 45455 + * (11.3.3.2 and 11.3.3.5 of the ISO PNG specification) the PNG specification + * makes it possible to derive values for other display systems and + * environments. + * + * The Mac value is deduced from the sRGB based on an assumption that the actual + * extra viewing correction used in early Mac display systems was implemented as + * a power 1.45 lookup table. + * + * Any system where a programmable lookup table is used or where the behavior of + * the final display device characteristics can be changed requires system + * specific code to obtain the current characteristic. However this can be + * difficult and most PNG gamma correction only requires an approximate value. + * + * By default, if png_set_alpha_mode() is not called, libpng assumes that all + * values are unencoded, linear, values and that the output device also has a + * linear characteristic. This is only very rarely correct - it is invariably + * better to call png_set_alpha_mode() with PNG_DEFAULT_sRGB than rely on the + * default if you don't know what the right answer is! + * + * The special value PNG_GAMMA_MAC_18 indicates an older Mac system (pre Mac OS + * 10.6) which used a correction table to implement a somewhat lower gamma on an + * otherwise sRGB system. + * + * Both these values are reserved (not simple gamma values) in order to allow + * more precise correction internally in the future. + * + * NOTE: the following values can be passed to either the fixed or floating + * point APIs, but the floating point API will also accept floating point + * values. + */ +#define PNG_DEFAULT_sRGB -1 /* sRGB gamma and color space */ +#define PNG_GAMMA_MAC_18 -2 /* Old Mac '1.8' gamma and color space */ +#define PNG_GAMMA_sRGB 220000 /* Television standards--matches sRGB gamma */ +#define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */ #endif -extern PNG_EXPORT(void,png_build_grayscale_palette) PNGARG((int bit_depth, - png_colorp palette)); +/* The following are examples of calls to png_set_alpha_mode to achieve the + * required overall gamma correction and, where necessary, alpha + * premultiplication. + * + * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); + * This is the default libpng handling of the alpha channel - it is not + * pre-multiplied into the color components. In addition the call states + * that the output is for a sRGB system and causes all PNG files without gAMA + * chunks to be assumed to be encoded using sRGB. + * + * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); + * In this case the output is assumed to be something like an sRGB conformant + * display preceeded by a power-law lookup table of power 1.45. This is how + * early Mac systems behaved. + * + * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR); + * This is the classic Jim Blinn approach and will work in academic + * environments where everything is done by the book. It has the shortcoming + * of assuming that input PNG data with no gamma information is linear - this + * is unlikely to be correct unless the PNG files where generated locally. + * Most of the time the output precision will be so low as to show + * significant banding in dark areas of the image. + * + * png_set_expand_16(pp); + * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB); + * This is a somewhat more realistic Jim Blinn inspired approach. PNG files + * are assumed to have the sRGB encoding if not marked with a gamma value and + * the output is always 16 bits per component. This permits accurate scaling + * and processing of the data. If you know that your input PNG files were + * generated locally you might need to replace PNG_DEFAULT_sRGB with the + * correct value for your system. + * + * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB); + * If you just need to composite the PNG image onto an existing background + * and if you control the code that does this you can use the optimization + * setting. In this case you just copy completely opaque pixels to the + * output. For pixels that are not completely transparent (you just skip + * those) you do the composition math using png_composite or png_composite_16 + * below then encode the resultant 8-bit or 16-bit values to match the output + * encoding. + * + * Other cases + * If neither the PNG nor the standard linear encoding work for you because + * of the software or hardware you use then you have a big problem. The PNG + * case will probably result in halos around the image. The linear encoding + * will probably result in a washed out, too bright, image (it's actually too + * contrasty.) Try the ALPHA_OPTIMIZED mode above - this will probably + * substantially reduce the halos. Alternatively try: + * + * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB); + * This option will also reduce the halos, but there will be slight dark + * halos round the opaque parts of the image where the background is light. + * In the OPTIMIZED mode the halos will be light halos where the background + * is dark. Take your pick - the halos are unavoidable unless you can get + * your hardware/software fixed! (The OPTIMIZED approach is slightly + * faster.) + * + * When the default gamma of PNG files doesn't match the output gamma. + * If you have PNG files with no gamma information png_set_alpha_mode allows + * you to provide a default gamma, but it also sets the ouput gamma to the + * matching value. If you know your PNG files have a gamma that doesn't + * match the output you can take advantage of the fact that + * png_set_alpha_mode always sets the output gamma but only sets the PNG + * default if it is not already set: + * + * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); + * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); + * The first call sets both the default and the output gamma values, the + * second call overrides the output gamma without changing the default. This + * is easier than achieving the same effect with png_set_gamma. You must use + * PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will + * fire if more than one call to png_set_alpha_mode and png_set_background is + * made in the same read operation, however multiple calls with PNG_ALPHA_PNG + * are ignored. + */ -#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED) -extern PNG_EXPORT(void,png_set_strip_alpha) PNGARG((png_structp png_ptr)); +#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED +PNG_EXPORT(36, void, png_set_strip_alpha, (png_structrp png_ptr)); #endif #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \ defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) -extern PNG_EXPORT(void,png_set_swap_alpha) PNGARG((png_structp png_ptr)); +PNG_EXPORT(37, void, png_set_swap_alpha, (png_structrp png_ptr)); #endif #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \ defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) -extern PNG_EXPORT(void,png_set_invert_alpha) PNGARG((png_structp png_ptr)); +PNG_EXPORT(38, void, png_set_invert_alpha, (png_structrp png_ptr)); #endif #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) -/* Add a filler byte to 24-bit RGB images. */ -extern PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr, - png_uint_32 filler, int flags)); +/* Add a filler byte to 8-bit Gray or 24-bit RGB images. */ +PNG_EXPORT(39, void, png_set_filler, (png_structrp png_ptr, png_uint_32 filler, + int flags)); /* The values of the PNG_FILLER_ defines should NOT be changed */ -#define PNG_FILLER_BEFORE 0 -#define PNG_FILLER_AFTER 1 +# define PNG_FILLER_BEFORE 0 +# define PNG_FILLER_AFTER 1 +/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */ +PNG_EXPORT(40, void, png_set_add_alpha, (png_structrp png_ptr, + png_uint_32 filler, int flags)); #endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */ #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) /* Swap bytes in 16-bit depth files. */ -extern PNG_EXPORT(void,png_set_swap) PNGARG((png_structp png_ptr)); +PNG_EXPORT(41, void, png_set_swap, (png_structrp png_ptr)); #endif #if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED) /* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */ -extern PNG_EXPORT(void,png_set_packing) PNGARG((png_structp png_ptr)); +PNG_EXPORT(42, void, png_set_packing, (png_structrp png_ptr)); #endif -#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED) +#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \ + defined(PNG_WRITE_PACKSWAP_SUPPORTED) /* Swap packing order of pixels in bytes. */ -extern PNG_EXPORT(void,png_set_packswap) PNGARG((png_structp png_ptr)); +PNG_EXPORT(43, void, png_set_packswap, (png_structrp png_ptr)); #endif #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED) /* Converts files to legal bit depths. */ -extern PNG_EXPORT(void,png_set_shift) PNGARG((png_structp png_ptr, - png_color_8p true_bits)); +PNG_EXPORT(44, void, png_set_shift, (png_structrp png_ptr, png_const_color_8p + true_bits)); #endif #if defined(PNG_READ_INTERLACING_SUPPORTED) || \ defined(PNG_WRITE_INTERLACING_SUPPORTED) -/* Have the code handle the interlacing. Returns the number of passes. */ -extern PNG_EXPORT(int,png_set_interlace_handling) PNGARG((png_structp png_ptr)); +/* Have the code handle the interlacing. Returns the number of passes. + * MUST be called before png_read_update_info or png_start_read_image, + * otherwise it will not have the desired effect. Note that it is still + * necessary to call png_read_row or png_read_rows png_get_image_height + * times for each pass. +*/ +PNG_EXPORT(45, int, png_set_interlace_handling, (png_structrp png_ptr)); #endif #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) /* Invert monochrome files */ -extern PNG_EXPORT(void,png_set_invert_mono) PNGARG((png_structp png_ptr)); +PNG_EXPORT(46, void, png_set_invert_mono, (png_structrp png_ptr)); #endif -#if defined(PNG_READ_BACKGROUND_SUPPORTED) -/* Handle alpha and tRNS by replacing with a background color. */ -#ifdef PNG_FLOATING_POINT_SUPPORTED -extern PNG_EXPORT(void,png_set_background) PNGARG((png_structp png_ptr, - png_color_16p background_color, int background_gamma_code, - int need_expand, double background_gamma)); +#ifdef PNG_READ_BACKGROUND_SUPPORTED +/* Handle alpha and tRNS by replacing with a background color. Prior to + * libpng-1.5.4 this API must not be called before the PNG file header has been + * read. Doing so will result in unexpected behavior and possible warnings or + * errors if the PNG file contains a bKGD chunk. + */ +PNG_FP_EXPORT(47, void, png_set_background, (png_structrp png_ptr, + png_const_color_16p background_color, int background_gamma_code, + int need_expand, double background_gamma)) +PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structrp png_ptr, + png_const_color_16p background_color, int background_gamma_code, + int need_expand, png_fixed_point background_gamma)) #endif -#define PNG_BACKGROUND_GAMMA_UNKNOWN 0 -#define PNG_BACKGROUND_GAMMA_SCREEN 1 -#define PNG_BACKGROUND_GAMMA_FILE 2 -#define PNG_BACKGROUND_GAMMA_UNIQUE 3 +#ifdef PNG_READ_BACKGROUND_SUPPORTED +# define PNG_BACKGROUND_GAMMA_UNKNOWN 0 +# define PNG_BACKGROUND_GAMMA_SCREEN 1 +# define PNG_BACKGROUND_GAMMA_FILE 2 +# define PNG_BACKGROUND_GAMMA_UNIQUE 3 #endif -#if defined(PNG_READ_16_TO_8_SUPPORTED) -/* strip the second byte of information from a 16-bit depth file. */ -extern PNG_EXPORT(void,png_set_strip_16) PNGARG((png_structp png_ptr)); +#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED +/* Scale a 16-bit depth file down to 8-bit, accurately. */ +PNG_EXPORT(229, void, png_set_scale_16, (png_structrp png_ptr)); #endif -#if defined(PNG_READ_DITHER_SUPPORTED) -/* Turn on dithering, and reduce the palette to the number of colors available. */ -extern PNG_EXPORT(void,png_set_dither) PNGARG((png_structp png_ptr, - png_colorp palette, int num_palette, int maximum_colors, - png_uint_16p histogram, int full_dither)); +#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED +#define PNG_READ_16_TO_8 SUPPORTED /* Name prior to 1.5.4 */ +/* Strip the second byte of information from a 16-bit depth file. */ +PNG_EXPORT(48, void, png_set_strip_16, (png_structrp png_ptr)); #endif -#if defined(PNG_READ_GAMMA_SUPPORTED) -/* Handle gamma correction. Screen_gamma=(display_exponent) */ -#ifdef PNG_FLOATING_POINT_SUPPORTED -extern PNG_EXPORT(void,png_set_gamma) PNGARG((png_structp png_ptr, - double screen_gamma, double default_file_gamma)); -#endif +#ifdef PNG_READ_QUANTIZE_SUPPORTED +/* Turn on quantizing, and reduce the palette to the number of colors + * available. + */ +PNG_EXPORT(49, void, png_set_quantize, (png_structrp png_ptr, + png_colorp palette, int num_palette, int maximum_colors, + png_const_uint_16p histogram, int full_quantize)); #endif -#if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \ - defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED) -/* Permit or disallow empty PLTE (0: not permitted, 1: permitted) */ -/* Deprecated and will be removed. Use png_permit_mng_features() instead. */ -extern PNG_EXPORT(void,png_permit_empty_plte) PNGARG((png_structp png_ptr, - int empty_plte_permitted)); +#ifdef PNG_READ_GAMMA_SUPPORTED +/* The threshold on gamma processing is configurable but hard-wired into the + * library. The following is the floating point variant. + */ +#define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001) + +/* Handle gamma correction. Screen_gamma=(display_exponent). + * NOTE: this API simply sets the screen and file gamma values. It will + * therefore override the value for gamma in a PNG file if it is called after + * the file header has been read - use with care - call before reading the PNG + * file for best results! + * + * These routines accept the same gamma values as png_set_alpha_mode (described + * above). The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either + * API (floating point or fixed.) Notice, however, that the 'file_gamma' value + * is the inverse of a 'screen gamma' value. + */ +PNG_FP_EXPORT(50, void, png_set_gamma, (png_structrp png_ptr, + double screen_gamma, double override_file_gamma)) +PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structrp png_ptr, + png_fixed_point screen_gamma, png_fixed_point override_file_gamma)) #endif -#if defined(PNG_WRITE_FLUSH_SUPPORTED) +#ifdef PNG_WRITE_FLUSH_SUPPORTED /* Set how many lines between output flushes - 0 for no flushing */ -extern PNG_EXPORT(void,png_set_flush) PNGARG((png_structp png_ptr, int nrows)); +PNG_EXPORT(51, void, png_set_flush, (png_structrp png_ptr, int nrows)); /* Flush the current PNG output buffer */ -extern PNG_EXPORT(void,png_write_flush) PNGARG((png_structp png_ptr)); +PNG_EXPORT(52, void, png_write_flush, (png_structrp png_ptr)); #endif -/* optional update palette with requested transformations */ -extern PNG_EXPORT(void,png_start_read_image) PNGARG((png_structp png_ptr)); +/* Optional update palette with requested transformations */ +PNG_EXPORT(53, void, png_start_read_image, (png_structrp png_ptr)); -/* optional call to update the users info structure */ -extern PNG_EXPORT(void,png_read_update_info) PNGARG((png_structp png_ptr, - png_infop info_ptr)); +/* Optional call to update the users info structure */ +PNG_EXPORT(54, void, png_read_update_info, (png_structrp png_ptr, + png_inforp info_ptr)); -/* read one or more rows of image data. */ -extern PNG_EXPORT(void,png_read_rows) PNGARG((png_structp png_ptr, - png_bytepp row, png_bytepp display_row, png_uint_32 num_rows)); - -/* read a row of data. */ -extern PNG_EXPORT(void,png_read_row) PNGARG((png_structp png_ptr, - png_bytep row, - png_bytep display_row)); - -/* read the whole image into memory at once. */ -extern PNG_EXPORT(void,png_read_image) PNGARG((png_structp png_ptr, - png_bytepp image)); +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read one or more rows of image data. */ +PNG_EXPORT(55, void, png_read_rows, (png_structrp png_ptr, png_bytepp row, + png_bytepp display_row, png_uint_32 num_rows)); +#endif -/* write a row of image data */ -extern PNG_EXPORT(void,png_write_row) PNGARG((png_structp png_ptr, - png_bytep row)); +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read a row of data. */ +PNG_EXPORT(56, void, png_read_row, (png_structrp png_ptr, png_bytep row, + png_bytep display_row)); +#endif -/* write a few rows of image data */ -extern PNG_EXPORT(void,png_write_rows) PNGARG((png_structp png_ptr, - png_bytepp row, png_uint_32 num_rows)); +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read the whole image into memory at once. */ +PNG_EXPORT(57, void, png_read_image, (png_structrp png_ptr, png_bytepp image)); +#endif -/* write the image data */ -extern PNG_EXPORT(void,png_write_image) PNGARG((png_structp png_ptr, - png_bytepp image)); +/* Write a row of image data */ +PNG_EXPORT(58, void, png_write_row, (png_structrp png_ptr, + png_const_bytep row)); -/* writes the end of the PNG file. */ -extern PNG_EXPORT(void,png_write_end) PNGARG((png_structp png_ptr, - png_infop info_ptr)); +/* Write a few rows of image data: (*row) is not written; however, the type + * is declared as writeable to maintain compatibility with previous versions + * of libpng and to allow the 'display_row' array from read_rows to be passed + * unchanged to write_rows. + */ +PNG_EXPORT(59, void, png_write_rows, (png_structrp png_ptr, png_bytepp row, + png_uint_32 num_rows)); -/* read the end of the PNG file. */ -extern PNG_EXPORT(void,png_read_end) PNGARG((png_structp png_ptr, - png_infop info_ptr)); +/* Write the image data */ +PNG_EXPORT(60, void, png_write_image, (png_structrp png_ptr, png_bytepp image)); -/* free any memory associated with the png_info_struct */ -extern PNG_EXPORT(void,png_destroy_info_struct) PNGARG((png_structp png_ptr, - png_infopp info_ptr_ptr)); +/* Write the end of the PNG file. */ +PNG_EXPORT(61, void, png_write_end, (png_structrp png_ptr, + png_inforp info_ptr)); -/* free any memory associated with the png_struct and the png_info_structs */ -extern PNG_EXPORT(void,png_destroy_read_struct) PNGARG((png_structpp - png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr)); +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read the end of the PNG file. */ +PNG_EXPORT(62, void, png_read_end, (png_structrp png_ptr, png_inforp info_ptr)); +#endif -/* free all memory used by the read (old method - NOT DLL EXPORTED) */ -extern void png_read_destroy PNGARG((png_structp png_ptr, png_infop info_ptr, - png_infop end_info_ptr)); +/* Free any memory associated with the png_info_struct */ +PNG_EXPORT(63, void, png_destroy_info_struct, (png_const_structrp png_ptr, + png_infopp info_ptr_ptr)); -/* free any memory associated with the png_struct and the png_info_structs */ -extern PNG_EXPORT(void,png_destroy_write_struct) - PNGARG((png_structpp png_ptr_ptr, png_infopp info_ptr_ptr)); +/* Free any memory associated with the png_struct and the png_info_structs */ +PNG_EXPORT(64, void, png_destroy_read_struct, (png_structpp png_ptr_ptr, + png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr)); -/* free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */ -extern void png_write_destroy PNGARG((png_structp png_ptr)); +/* Free any memory associated with the png_struct and the png_info_structs */ +PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr, + png_infopp info_ptr_ptr)); -/* set the libpng method of handling chunk CRC errors */ -extern PNG_EXPORT(void,png_set_crc_action) PNGARG((png_structp png_ptr, - int crit_action, int ancil_action)); +/* Set the libpng method of handling chunk CRC errors */ +PNG_EXPORT(66, void, png_set_crc_action, (png_structrp png_ptr, int crit_action, + int ancil_action)); -/* Values for png_set_crc_action() to say how to handle CRC errors in +/* Values for png_set_crc_action() say how to handle CRC errors in * ancillary and critical chunks, and whether to use the data contained * therein. Note that it is impossible to "discard" data in a critical * chunk. For versions prior to 0.90, the action was always error/quit, @@ -1621,11 +1621,11 @@ extern PNG_EXPORT(void,png_set_crc_action) PNGARG((png_structp png_ptr, * header file (zlib.h) for an explination of the compression functions. */ -/* set the filtering method(s) used by libpng. Currently, the only valid +/* Set the filtering method(s) used by libpng. Currently, the only valid * value for "method" is 0. */ -extern PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method, - int filters)); +PNG_EXPORT(67, void, png_set_filter, (png_structrp png_ptr, int method, + int filters)); /* Flags for png_set_filter() to say which filters to use. The flags * are chosen so that they don't conflict with real filter types @@ -1651,7 +1651,7 @@ extern PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method, #define PNG_FILTER_VALUE_PAETH 4 #define PNG_FILTER_VALUE_LAST 5 -#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* EXPERIMENTAL */ +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* EXPERIMENTAL */ /* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_ * defines, either the default (minimum-sum-of-absolute-differences), or * the experimental method (weighted-minimum-sum-of-absolute-differences). @@ -1680,11 +1680,13 @@ extern PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method, * the weights and costs are set to 1.0, this degenerates the WEIGHTED method * to the UNWEIGHTED method, but with added encoding time/computation. */ -#ifdef PNG_FLOATING_POINT_SUPPORTED -extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr, - int heuristic_method, int num_weights, png_doublep filter_weights, - png_doublep filter_costs)); -#endif +PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structrp png_ptr, + int heuristic_method, int num_weights, png_const_doublep filter_weights, + png_const_doublep filter_costs)) +PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed, + (png_structrp png_ptr, int heuristic_method, int num_weights, + png_const_fixed_point_p filter_weights, + png_const_fixed_point_p filter_costs)) #endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */ /* Heuristic used for row filter selection. These defines should NOT be @@ -1695,6 +1697,7 @@ extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr, #define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */ #define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */ +#ifdef PNG_WRITE_SUPPORTED /* Set the library compression level. Currently, valid values range from * 0 - 9, corresponding directly to the zlib compression levels 0 - 9 * (0 - no compression, 9 - "maximal" compression). Note that tests have @@ -1702,33 +1705,58 @@ extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr, * for PNG images, and do considerably fewer caclulations. In the future, * these values may not correspond directly to the zlib compression levels. */ -extern PNG_EXPORT(void,png_set_compression_level) PNGARG((png_structp png_ptr, - int level)); +PNG_EXPORT(69, void, png_set_compression_level, (png_structrp png_ptr, + int level)); + +PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structrp png_ptr, + int mem_level)); -extern PNG_EXPORT(void,png_set_compression_mem_level) - PNGARG((png_structp png_ptr, int mem_level)); +PNG_EXPORT(71, void, png_set_compression_strategy, (png_structrp png_ptr, + int strategy)); -extern PNG_EXPORT(void,png_set_compression_strategy) - PNGARG((png_structp png_ptr, int strategy)); +/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a + * smaller value of window_bits if it can do so safely. + */ +PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structrp png_ptr, + int window_bits)); + +PNG_EXPORT(73, void, png_set_compression_method, (png_structrp png_ptr, + int method)); +#endif -extern PNG_EXPORT(void,png_set_compression_window_bits) - PNGARG((png_structp png_ptr, int window_bits)); +#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED +/* Also set zlib parameters for compressing non-IDAT chunks */ +PNG_EXPORT(222, void, png_set_text_compression_level, (png_structrp png_ptr, + int level)); -extern PNG_EXPORT(void,png_set_compression_method) PNGARG((png_structp png_ptr, - int method)); +PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structrp png_ptr, + int mem_level)); + +PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structrp png_ptr, + int strategy)); + +/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a + * smaller value of window_bits if it can do so safely. + */ +PNG_EXPORT(225, void, png_set_text_compression_window_bits, + (png_structrp png_ptr, int window_bits)); + +PNG_EXPORT(226, void, png_set_text_compression_method, (png_structrp png_ptr, + int method)); +#endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */ /* These next functions are called for input/output, memory, and error * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c, * and call standard C I/O routines such as fread(), fwrite(), and * fprintf(). These functions can be made to use other I/O routines * at run time for those applications that need to handle I/O in a - * different manner by calling png_set_???_fn(). See libpng.txt for + * different manner by calling png_set_???_fn(). See libpng-manual.txt for * more information. */ -#if !defined(PNG_NO_STDIO) +#ifdef PNG_STDIO_SUPPORTED /* Initialize the input/output for the PNG file to the default functions. */ -extern PNG_EXPORT(void,png_init_io) PNGARG((png_structp png_ptr, png_FILE_p fp)); +PNG_EXPORT(74, void, png_init_io, (png_structrp png_ptr, png_FILE_p fp)); #endif /* Replace the (error and abort), and warning functions with user @@ -1739,128 +1767,181 @@ extern PNG_EXPORT(void,png_init_io) PNGARG((png_structp png_ptr, png_FILE_p fp)) * default function will be used. */ -extern PNG_EXPORT(void,png_set_error_fn) PNGARG((png_structp png_ptr, - png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn)); +PNG_EXPORT(75, void, png_set_error_fn, (png_structrp png_ptr, + png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn)); /* Return the user pointer associated with the error functions */ -extern PNG_EXPORT(png_voidp,png_get_error_ptr) PNGARG((png_structp png_ptr)); +PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structrp png_ptr)); /* Replace the default data output functions with a user supplied one(s). * If buffered output is not used, then output_flush_fn can be set to NULL. * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time * output_flush_fn will be ignored (and thus can be NULL). + * It is probably a mistake to use NULL for output_flush_fn if + * write_data_fn is not also NULL unless you have built libpng with + * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's + * default flush function, which uses the standard *FILE structure, will + * be used. */ -extern PNG_EXPORT(void,png_set_write_fn) PNGARG((png_structp png_ptr, - png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)); +PNG_EXPORT(77, void, png_set_write_fn, (png_structrp png_ptr, png_voidp io_ptr, + png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)); /* Replace the default data input function with a user supplied one. */ -extern PNG_EXPORT(void,png_set_read_fn) PNGARG((png_structp png_ptr, - png_voidp io_ptr, png_rw_ptr read_data_fn)); +PNG_EXPORT(78, void, png_set_read_fn, (png_structrp png_ptr, png_voidp io_ptr, + png_rw_ptr read_data_fn)); /* Return the user pointer associated with the I/O functions */ -extern PNG_EXPORT(png_voidp,png_get_io_ptr) PNGARG((png_structp png_ptr)); +PNG_EXPORT(79, png_voidp, png_get_io_ptr, (png_const_structrp png_ptr)); -extern PNG_EXPORT(void,png_set_read_status_fn) PNGARG((png_structp png_ptr, - png_read_status_ptr read_row_fn)); +PNG_EXPORT(80, void, png_set_read_status_fn, (png_structrp png_ptr, + png_read_status_ptr read_row_fn)); -extern PNG_EXPORT(void,png_set_write_status_fn) PNGARG((png_structp png_ptr, - png_write_status_ptr write_row_fn)); +PNG_EXPORT(81, void, png_set_write_status_fn, (png_structrp png_ptr, + png_write_status_ptr write_row_fn)); #ifdef PNG_USER_MEM_SUPPORTED /* Replace the default memory allocation functions with user supplied one(s). */ -extern PNG_EXPORT(void,png_set_mem_fn) PNGARG((png_structp png_ptr, - png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn)); +PNG_EXPORT(82, void, png_set_mem_fn, (png_structrp png_ptr, png_voidp mem_ptr, + png_malloc_ptr malloc_fn, png_free_ptr free_fn)); /* Return the user pointer associated with the memory functions */ -extern PNG_EXPORT(png_voidp,png_get_mem_ptr) PNGARG((png_structp png_ptr)); +PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structrp png_ptr)); #endif -#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ - defined(PNG_LEGACY_SUPPORTED) -extern PNG_EXPORT(void,png_set_read_user_transform_fn) PNGARG((png_structp - png_ptr, png_user_transform_ptr read_user_transform_fn)); +#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED +PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structrp png_ptr, + png_user_transform_ptr read_user_transform_fn)); #endif -#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \ - defined(PNG_LEGACY_SUPPORTED) -extern PNG_EXPORT(void,png_set_write_user_transform_fn) PNGARG((png_structp - png_ptr, png_user_transform_ptr write_user_transform_fn)); +#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED +PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structrp png_ptr, + png_user_transform_ptr write_user_transform_fn)); #endif -#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ - defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \ - defined(PNG_LEGACY_SUPPORTED) -extern PNG_EXPORT(void,png_set_user_transform_info) PNGARG((png_structp - png_ptr, png_voidp user_transform_ptr, int user_transform_depth, - int user_transform_channels)); +#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED +PNG_EXPORT(86, void, png_set_user_transform_info, (png_structrp png_ptr, + png_voidp user_transform_ptr, int user_transform_depth, + int user_transform_channels)); /* Return the user pointer associated with the user transform functions */ -extern PNG_EXPORT(png_voidp,png_get_user_transform_ptr) - PNGARG((png_structp png_ptr)); +PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr, + (png_const_structrp png_ptr)); +#endif + +#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED +/* Return information about the row currently being processed. Note that these + * APIs do not fail but will return unexpected results if called outside a user + * transform callback. Also note that when transforming an interlaced image the + * row number is the row number within the sub-image of the interlace pass, so + * the value will increase to the height of the sub-image (not the full image) + * then reset to 0 for the next pass. + * + * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to + * find the output pixel (x,y) given an interlaced sub-image pixel + * (row,col,pass). (See below for these macros.) + */ +PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structrp)); +PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structrp)); +#endif + +#ifdef PNG_READ_USER_CHUNKS_SUPPORTED +/* This callback is called only for *unknown* chunks. If + * PNG_HANDLE_AS_UNKNOWN_SUPPORTED is set then it is possible to set known + * chunks to be treated as unknown, however in this case the callback must do + * any processing required by the chunk (e.g. by calling the appropriate + * png_set_ APIs.) + * + * There is no write support - on write, by default, all the chunks in the + * 'unknown' list are written in the specified position. + * + * The integer return from the callback function is interpreted thus: + * + * negative: An error occured, png_chunk_error will be called. + * zero: The chunk was not handled, the chunk will be saved. A critical + * chunk will cause an error at this point unless it is to be saved. + * positive: The chunk was handled, libpng will ignore/discard it. + * + * See "INTERACTION WTIH USER CHUNK CALLBACKS" below for important notes about + * how this behavior will change in libpng 1.7 + */ +PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structrp png_ptr, + png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn)); #endif #ifdef PNG_USER_CHUNKS_SUPPORTED -extern PNG_EXPORT(void,png_set_read_user_chunk_fn) PNGARG((png_structp png_ptr, - png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn)); -extern PNG_EXPORT(png_voidp,png_get_user_chunk_ptr) PNGARG((png_structp - png_ptr)); +PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structrp png_ptr)); #endif #ifdef PNG_PROGRESSIVE_READ_SUPPORTED /* Sets the function callbacks for the push reader, and a pointer to a * user-defined structure available to the callback functions. */ -extern PNG_EXPORT(void,png_set_progressive_read_fn) PNGARG((png_structp png_ptr, - png_voidp progressive_ptr, - png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn, - png_progressive_end_ptr end_fn)); - -/* returns the user pointer associated with the push read functions */ -extern PNG_EXPORT(png_voidp,png_get_progressive_ptr) - PNGARG((png_structp png_ptr)); +PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structrp png_ptr, + png_voidp progressive_ptr, png_progressive_info_ptr info_fn, + png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn)); + +/* Returns the user pointer associated with the push read functions */ +PNG_EXPORT(91, png_voidp, png_get_progressive_ptr, + (png_const_structrp png_ptr)); + +/* Function to be called when data becomes available */ +PNG_EXPORT(92, void, png_process_data, (png_structrp png_ptr, + png_inforp info_ptr, png_bytep buffer, png_size_t buffer_size)); + +/* A function which may be called *only* within png_process_data to stop the + * processing of any more data. The function returns the number of bytes + * remaining, excluding any that libpng has cached internally. A subsequent + * call to png_process_data must supply these bytes again. If the argument + * 'save' is set to true the routine will first save all the pending data and + * will always return 0. + */ +PNG_EXPORT(219, png_size_t, png_process_data_pause, (png_structrp, int save)); -/* function to be called when data becomes available */ -extern PNG_EXPORT(void,png_process_data) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_bytep buffer, png_size_t buffer_size)); +/* A function which may be called *only* outside (after) a call to + * png_process_data. It returns the number of bytes of data to skip in the + * input. Normally it will return 0, but if it returns a non-zero value the + * application must skip than number of bytes of input data and pass the + * following data to the next call to png_process_data. + */ +PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structrp)); -/* function that combines rows. Not very much different than the - * png_combine_row() call. Is this even used????? +#ifdef PNG_READ_INTERLACING_SUPPORTED +/* Function that combines rows. 'new_row' is a flag that should come from + * the callback and be non-NULL if anything needs to be done; the library + * stores its own version of the new data internally and ignores the passed + * in value. */ -extern PNG_EXPORT(void,png_progressive_combine_row) PNGARG((png_structp png_ptr, - png_bytep old_row, png_bytep new_row)); +PNG_EXPORT(93, void, png_progressive_combine_row, (png_const_structrp png_ptr, + png_bytep old_row, png_const_bytep new_row)); +#endif /* PNG_READ_INTERLACING_SUPPORTED */ #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ -extern PNG_EXPORT(png_voidp,png_malloc) PNGARG((png_structp png_ptr, - png_uint_32 size)); +PNG_EXPORTA(94, png_voidp, png_malloc, (png_const_structrp png_ptr, + png_alloc_size_t size), PNG_ALLOCATED); +/* Added at libpng version 1.4.0 */ +PNG_EXPORTA(95, png_voidp, png_calloc, (png_const_structrp png_ptr, + png_alloc_size_t size), PNG_ALLOCATED); -#if defined(PNG_1_0_X) -# define png_malloc_warn png_malloc -#else /* Added at libpng version 1.2.4 */ -extern PNG_EXPORT(png_voidp,png_malloc_warn) PNGARG((png_structp png_ptr, - png_uint_32 size)); -#endif - -/* frees a pointer allocated by png_malloc() */ -extern PNG_EXPORT(void,png_free) PNGARG((png_structp png_ptr, png_voidp ptr)); +PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_const_structrp png_ptr, + png_alloc_size_t size), PNG_ALLOCATED); -#if defined(PNG_1_0_X) -/* Function to allocate memory for zlib. */ -extern PNG_EXPORT(voidpf,png_zalloc) PNGARG((voidpf png_ptr, uInt items, - uInt size)); - -/* Function to free memory for zlib */ -extern PNG_EXPORT(void,png_zfree) PNGARG((voidpf png_ptr, voidpf ptr)); -#endif +/* Frees a pointer allocated by png_malloc() */ +PNG_EXPORT(97, void, png_free, (png_const_structrp png_ptr, png_voidp ptr)); /* Free data that was allocated internally */ -extern PNG_EXPORT(void,png_free_data) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_uint_32 free_me, int num)); -#ifdef PNG_FREE_ME_SUPPORTED +PNG_EXPORT(98, void, png_free_data, (png_const_structrp png_ptr, + png_inforp info_ptr, png_uint_32 free_me, int num)); + /* Reassign responsibility for freeing existing data, whether allocated - * by libpng or by the application */ -extern PNG_EXPORT(void,png_data_freer) PNGARG((png_structp png_ptr, - png_infop info_ptr, int freer, png_uint_32 mask)); -#endif -/* assignments for png_data_freer */ + * by libpng or by the application; this works on the png_info structure passed + * in, it does not change the state for other png_info structures. + * + * It is unlikely that this function works correctly as of 1.6.0 and using it + * may result either in memory leaks or double free of allocated data. + */ +PNG_EXPORTA(99, void, png_data_freer, (png_const_structrp png_ptr, + png_inforp info_ptr, int freer, png_uint_32 mask), PNG_DEPRECATED); + +/* Assignments for png_data_freer */ #define PNG_DESTROY_WILL_FREE_DATA 1 #define PNG_SET_WILL_FREE_DATA 1 #define PNG_USER_WILL_FREE_DATA 2 @@ -1871,8 +1952,10 @@ extern PNG_EXPORT(void,png_data_freer) PNGARG((png_structp png_ptr, #define PNG_FREE_ROWS 0x0040 #define PNG_FREE_PCAL 0x0080 #define PNG_FREE_SCAL 0x0100 -#define PNG_FREE_UNKN 0x0200 -#define PNG_FREE_LIST 0x0400 +#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED +# define PNG_FREE_UNKN 0x0200 +#endif +/* PNG_FREE_LIST 0x0400 removed in 1.6.0 because it is ignored */ #define PNG_FREE_PLTE 0x1000 #define PNG_FREE_TRNS 0x2000 #define PNG_FREE_TEXT 0x4000 @@ -1880,38 +1963,59 @@ extern PNG_EXPORT(void,png_data_freer) PNGARG((png_structp png_ptr, #define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */ #ifdef PNG_USER_MEM_SUPPORTED -extern PNG_EXPORT(png_voidp,png_malloc_default) PNGARG((png_structp png_ptr, - png_uint_32 size)); -extern PNG_EXPORT(void,png_free_default) PNGARG((png_structp png_ptr, - png_voidp ptr)); +PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_const_structrp png_ptr, + png_alloc_size_t size), PNG_ALLOCATED PNG_DEPRECATED); +PNG_EXPORTA(101, void, png_free_default, (png_const_structrp png_ptr, + png_voidp ptr), PNG_DEPRECATED); #endif -extern PNG_EXPORT(png_voidp,png_memcpy_check) PNGARG((png_structp png_ptr, - png_voidp s1, png_voidp s2, png_uint_32 size)); - -extern PNG_EXPORT(png_voidp,png_memset_check) PNGARG((png_structp png_ptr, - png_voidp s1, int value, png_uint_32 size)); - -#if defined(USE_FAR_KEYWORD) /* memory model conversion function */ -extern void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr, - int check)); -#endif /* USE_FAR_KEYWORD */ - +#ifdef PNG_ERROR_TEXT_SUPPORTED /* Fatal error in PNG image of libpng - can't continue */ -extern PNG_EXPORT(void,png_error) PNGARG((png_structp png_ptr, - png_const_charp error_message)); +PNG_EXPORTA(102, void, png_error, (png_const_structrp png_ptr, + png_const_charp error_message), PNG_NORETURN); /* The same, but the chunk name is prepended to the error string. */ -extern PNG_EXPORT(void,png_chunk_error) PNGARG((png_structp png_ptr, - png_const_charp error_message)); +PNG_EXPORTA(103, void, png_chunk_error, (png_const_structrp png_ptr, + png_const_charp error_message), PNG_NORETURN); +#else +/* Fatal error in PNG image of libpng - can't continue */ +PNG_EXPORTA(104, void, png_err, (png_const_structrp png_ptr), PNG_NORETURN); +#endif + +#ifdef PNG_WARNINGS_SUPPORTED /* Non-fatal error in libpng. Can continue, but may have a problem. */ -extern PNG_EXPORT(void,png_warning) PNGARG((png_structp png_ptr, - png_const_charp warning_message)); +PNG_EXPORT(105, void, png_warning, (png_const_structrp png_ptr, + png_const_charp warning_message)); /* Non-fatal error in libpng, chunk name is prepended to message. */ -extern PNG_EXPORT(void,png_chunk_warning) PNGARG((png_structp png_ptr, - png_const_charp warning_message)); +PNG_EXPORT(106, void, png_chunk_warning, (png_const_structrp png_ptr, + png_const_charp warning_message)); +#endif + +#ifdef PNG_BENIGN_ERRORS_SUPPORTED +/* Benign error in libpng. Can continue, but may have a problem. + * User can choose whether to handle as a fatal error or as a warning. */ +PNG_EXPORT(107, void, png_benign_error, (png_const_structrp png_ptr, + png_const_charp warning_message)); + +#ifdef PNG_READ_SUPPORTED +/* Same, chunk name is prepended to message (only during read) */ +PNG_EXPORT(108, void, png_chunk_benign_error, (png_const_structrp png_ptr, + png_const_charp warning_message)); +#endif + +PNG_EXPORT(109, void, png_set_benign_errors, + (png_structrp png_ptr, int allowed)); +#else +# ifdef PNG_ALLOW_BENIGN_ERRORS +# define png_benign_error png_warning +# define png_chunk_benign_error png_chunk_warning +# else +# define png_benign_error png_error +# define png_chunk_benign_error png_chunk_error +# endif +#endif /* The png_set_ functions are for storing values in the png_info_struct. * Similarly, the png_get_ calls are used to read values from the @@ -1926,502 +2030,647 @@ extern PNG_EXPORT(void,png_chunk_warning) PNGARG((png_structp png_ptr, * png_info_struct. */ /* Returns "flag" if chunk data is valid in info_ptr. */ -extern PNG_EXPORT(png_uint_32,png_get_valid) PNGARG((png_structp png_ptr, -png_infop info_ptr, png_uint_32 flag)); +PNG_EXPORT(110, png_uint_32, png_get_valid, (png_const_structrp png_ptr, + png_const_inforp info_ptr, png_uint_32 flag)); /* Returns number of bytes needed to hold a transformed row. */ -extern PNG_EXPORT(png_uint_32,png_get_rowbytes) PNGARG((png_structp png_ptr, -png_infop info_ptr)); +PNG_EXPORT(111, png_size_t, png_get_rowbytes, (png_const_structrp png_ptr, + png_const_inforp info_ptr)); -#if defined(PNG_INFO_IMAGE_SUPPORTED) +#ifdef PNG_INFO_IMAGE_SUPPORTED /* Returns row_pointers, which is an array of pointers to scanlines that was -returned from png_read_png(). */ -extern PNG_EXPORT(png_bytepp,png_get_rows) PNGARG((png_structp png_ptr, -png_infop info_ptr)); + * returned from png_read_png(). + */ +PNG_EXPORT(112, png_bytepp, png_get_rows, (png_const_structrp png_ptr, + png_const_inforp info_ptr)); + /* Set row_pointers, which is an array of pointers to scanlines for use -by png_write_png(). */ -extern PNG_EXPORT(void,png_set_rows) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_bytepp row_pointers)); + * by png_write_png(). + */ +PNG_EXPORT(113, void, png_set_rows, (png_const_structrp png_ptr, + png_inforp info_ptr, png_bytepp row_pointers)); #endif /* Returns number of color channels in image. */ -extern PNG_EXPORT(png_byte,png_get_channels) PNGARG((png_structp png_ptr, -png_infop info_ptr)); +PNG_EXPORT(114, png_byte, png_get_channels, (png_const_structrp png_ptr, + png_const_inforp info_ptr)); #ifdef PNG_EASY_ACCESS_SUPPORTED /* Returns image width in pixels. */ -extern PNG_EXPORT(png_uint_32, png_get_image_width) PNGARG((png_structp -png_ptr, png_infop info_ptr)); +PNG_EXPORT(115, png_uint_32, png_get_image_width, (png_const_structrp png_ptr, + png_const_inforp info_ptr)); /* Returns image height in pixels. */ -extern PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp -png_ptr, png_infop info_ptr)); +PNG_EXPORT(116, png_uint_32, png_get_image_height, (png_const_structrp png_ptr, + png_const_inforp info_ptr)); /* Returns image bit_depth. */ -extern PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp -png_ptr, png_infop info_ptr)); +PNG_EXPORT(117, png_byte, png_get_bit_depth, (png_const_structrp png_ptr, + png_const_inforp info_ptr)); /* Returns image color_type. */ -extern PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp -png_ptr, png_infop info_ptr)); +PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structrp png_ptr, + png_const_inforp info_ptr)); /* Returns image filter_type. */ -extern PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp -png_ptr, png_infop info_ptr)); +PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structrp png_ptr, + png_const_inforp info_ptr)); /* Returns image interlace_type. */ -extern PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp -png_ptr, png_infop info_ptr)); +PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structrp png_ptr, + png_const_inforp info_ptr)); /* Returns image compression_type. */ -extern PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp -png_ptr, png_infop info_ptr)); +PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structrp png_ptr, + png_const_inforp info_ptr)); /* Returns image resolution in pixels per meter, from pHYs chunk data. */ -extern PNG_EXPORT(png_uint_32, png_get_pixels_per_meter) PNGARG((png_structp -png_ptr, png_infop info_ptr)); -extern PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter) PNGARG((png_structp -png_ptr, png_infop info_ptr)); -extern PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter) PNGARG((png_structp -png_ptr, png_infop info_ptr)); +PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter, + (png_const_structrp png_ptr, png_const_inforp info_ptr)); +PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter, + (png_const_structrp png_ptr, png_const_inforp info_ptr)); +PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter, + (png_const_structrp png_ptr, png_const_inforp info_ptr)); /* Returns pixel aspect ratio, computed from pHYs chunk data. */ -#ifdef PNG_FLOATING_POINT_SUPPORTED -extern PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp -png_ptr, png_infop info_ptr)); -#endif +PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio, + (png_const_structrp png_ptr, png_const_inforp info_ptr)) +PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed, + (png_const_structrp png_ptr, png_const_inforp info_ptr)) /* Returns image x, y offset in pixels or microns, from oFFs chunk data. */ -extern PNG_EXPORT(png_int_32, png_get_x_offset_pixels) PNGARG((png_structp -png_ptr, png_infop info_ptr)); -extern PNG_EXPORT(png_int_32, png_get_y_offset_pixels) PNGARG((png_structp -png_ptr, png_infop info_ptr)); -extern PNG_EXPORT(png_int_32, png_get_x_offset_microns) PNGARG((png_structp -png_ptr, png_infop info_ptr)); -extern PNG_EXPORT(png_int_32, png_get_y_offset_microns) PNGARG((png_structp -png_ptr, png_infop info_ptr)); +PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels, + (png_const_structrp png_ptr, png_const_inforp info_ptr)); +PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels, + (png_const_structrp png_ptr, png_const_inforp info_ptr)); +PNG_EXPORT(128, png_int_32, png_get_x_offset_microns, + (png_const_structrp png_ptr, png_const_inforp info_ptr)); +PNG_EXPORT(129, png_int_32, png_get_y_offset_microns, + (png_const_structrp png_ptr, png_const_inforp info_ptr)); #endif /* PNG_EASY_ACCESS_SUPPORTED */ +#ifdef PNG_READ_SUPPORTED /* Returns pointer to signature string read from PNG header */ -extern PNG_EXPORT(png_bytep,png_get_signature) PNGARG((png_structp png_ptr, -png_infop info_ptr)); - -#if defined(PNG_bKGD_SUPPORTED) -extern PNG_EXPORT(png_uint_32,png_get_bKGD) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_color_16p *background)); +PNG_EXPORT(130, png_const_bytep, png_get_signature, (png_const_structrp png_ptr, + png_const_inforp info_ptr)); #endif -#if defined(PNG_bKGD_SUPPORTED) -extern PNG_EXPORT(void,png_set_bKGD) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_color_16p background)); +#ifdef PNG_bKGD_SUPPORTED +PNG_EXPORT(131, png_uint_32, png_get_bKGD, (png_const_structrp png_ptr, + png_inforp info_ptr, png_color_16p *background)); #endif -#if defined(PNG_cHRM_SUPPORTED) -#ifdef PNG_FLOATING_POINT_SUPPORTED -extern PNG_EXPORT(png_uint_32,png_get_cHRM) PNGARG((png_structp png_ptr, - png_infop info_ptr, double *white_x, double *white_y, double *red_x, - double *red_y, double *green_x, double *green_y, double *blue_x, - double *blue_y)); -#endif -#ifdef PNG_FIXED_POINT_SUPPORTED -extern PNG_EXPORT(png_uint_32,png_get_cHRM_fixed) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_fixed_point *int_white_x, png_fixed_point - *int_white_y, png_fixed_point *int_red_x, png_fixed_point *int_red_y, - png_fixed_point *int_green_x, png_fixed_point *int_green_y, png_fixed_point - *int_blue_x, png_fixed_point *int_blue_y)); -#endif -#endif - -#if defined(PNG_cHRM_SUPPORTED) -#ifdef PNG_FLOATING_POINT_SUPPORTED -extern PNG_EXPORT(void,png_set_cHRM) PNGARG((png_structp png_ptr, - png_infop info_ptr, double white_x, double white_y, double red_x, - double red_y, double green_x, double green_y, double blue_x, double blue_y)); -#endif -#ifdef PNG_FIXED_POINT_SUPPORTED -extern PNG_EXPORT(void,png_set_cHRM_fixed) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_fixed_point int_white_x, png_fixed_point int_white_y, - png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point - int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x, - png_fixed_point int_blue_y)); -#endif -#endif - -#if defined(PNG_gAMA_SUPPORTED) -#ifdef PNG_FLOATING_POINT_SUPPORTED -extern PNG_EXPORT(png_uint_32,png_get_gAMA) PNGARG((png_structp png_ptr, - png_infop info_ptr, double *file_gamma)); -#endif -extern PNG_EXPORT(png_uint_32,png_get_gAMA_fixed) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_fixed_point *int_file_gamma)); -#endif - -#if defined(PNG_gAMA_SUPPORTED) -#ifdef PNG_FLOATING_POINT_SUPPORTED -extern PNG_EXPORT(void,png_set_gAMA) PNGARG((png_structp png_ptr, - png_infop info_ptr, double file_gamma)); -#endif -extern PNG_EXPORT(void,png_set_gAMA_fixed) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_fixed_point int_file_gamma)); -#endif - -#if defined(PNG_hIST_SUPPORTED) -extern PNG_EXPORT(png_uint_32,png_get_hIST) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_uint_16p *hist)); +#ifdef PNG_bKGD_SUPPORTED +PNG_EXPORT(132, void, png_set_bKGD, (png_const_structrp png_ptr, + png_inforp info_ptr, png_const_color_16p background)); #endif -#if defined(PNG_hIST_SUPPORTED) -extern PNG_EXPORT(void,png_set_hIST) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_uint_16p hist)); +#ifdef PNG_cHRM_SUPPORTED +PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structrp png_ptr, + png_const_inforp info_ptr, double *white_x, double *white_y, double *red_x, + double *red_y, double *green_x, double *green_y, double *blue_x, + double *blue_y)) +PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_const_structrp png_ptr, + png_const_inforp info_ptr, double *red_X, double *red_Y, double *red_Z, + double *green_X, double *green_Y, double *green_Z, double *blue_X, + double *blue_Y, double *blue_Z)) +PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed, + (png_const_structrp png_ptr, png_const_inforp info_ptr, + png_fixed_point *int_white_x, png_fixed_point *int_white_y, + png_fixed_point *int_red_x, png_fixed_point *int_red_y, + png_fixed_point *int_green_x, png_fixed_point *int_green_y, + png_fixed_point *int_blue_x, png_fixed_point *int_blue_y)) +PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed, + (png_const_structrp png_ptr, png_const_inforp info_ptr, + png_fixed_point *int_red_X, png_fixed_point *int_red_Y, + png_fixed_point *int_red_Z, png_fixed_point *int_green_X, + png_fixed_point *int_green_Y, png_fixed_point *int_green_Z, + png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y, + png_fixed_point *int_blue_Z)) #endif -extern PNG_EXPORT(png_uint_32,png_get_IHDR) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_uint_32 *width, png_uint_32 *height, - int *bit_depth, int *color_type, int *interlace_method, - int *compression_method, int *filter_method)); - -extern PNG_EXPORT(void,png_set_IHDR) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth, - int color_type, int interlace_method, int compression_method, - int filter_method)); - -#if defined(PNG_oFFs_SUPPORTED) -extern PNG_EXPORT(png_uint_32,png_get_oFFs) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_int_32 *offset_x, png_int_32 *offset_y, +#ifdef PNG_cHRM_SUPPORTED +PNG_FP_EXPORT(135, void, png_set_cHRM, (png_const_structrp png_ptr, + png_inforp info_ptr, + double white_x, double white_y, double red_x, double red_y, double green_x, + double green_y, double blue_x, double blue_y)) +PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_const_structrp png_ptr, + png_inforp info_ptr, double red_X, double red_Y, double red_Z, + double green_X, double green_Y, double green_Z, double blue_X, + double blue_Y, double blue_Z)) +PNG_FIXED_EXPORT(136, void, png_set_cHRM_fixed, (png_const_structrp png_ptr, + png_inforp info_ptr, png_fixed_point int_white_x, + png_fixed_point int_white_y, png_fixed_point int_red_x, + png_fixed_point int_red_y, png_fixed_point int_green_x, + png_fixed_point int_green_y, png_fixed_point int_blue_x, + png_fixed_point int_blue_y)) +PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_const_structrp png_ptr, + png_inforp info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y, + png_fixed_point int_red_Z, png_fixed_point int_green_X, + png_fixed_point int_green_Y, png_fixed_point int_green_Z, + png_fixed_point int_blue_X, png_fixed_point int_blue_Y, + png_fixed_point int_blue_Z)) +#endif + +#ifdef PNG_gAMA_SUPPORTED +PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA, (png_const_structrp png_ptr, + png_const_inforp info_ptr, double *file_gamma)) +PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed, + (png_const_structrp png_ptr, png_const_inforp info_ptr, + png_fixed_point *int_file_gamma)) +#endif + +#ifdef PNG_gAMA_SUPPORTED +PNG_FP_EXPORT(139, void, png_set_gAMA, (png_const_structrp png_ptr, + png_inforp info_ptr, double file_gamma)) +PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_const_structrp png_ptr, + png_inforp info_ptr, png_fixed_point int_file_gamma)) +#endif + +#ifdef PNG_hIST_SUPPORTED +PNG_EXPORT(141, png_uint_32, png_get_hIST, (png_const_structrp png_ptr, + png_inforp info_ptr, png_uint_16p *hist)); +#endif + +#ifdef PNG_hIST_SUPPORTED +PNG_EXPORT(142, void, png_set_hIST, (png_const_structrp png_ptr, + png_inforp info_ptr, png_const_uint_16p hist)); +#endif + +PNG_EXPORT(143, png_uint_32, png_get_IHDR, (png_const_structrp png_ptr, + png_const_inforp info_ptr, png_uint_32 *width, png_uint_32 *height, + int *bit_depth, int *color_type, int *interlace_method, + int *compression_method, int *filter_method)); + +PNG_EXPORT(144, void, png_set_IHDR, (png_const_structrp png_ptr, + png_inforp info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth, + int color_type, int interlace_method, int compression_method, + int filter_method)); + +#ifdef PNG_oFFs_SUPPORTED +PNG_EXPORT(145, png_uint_32, png_get_oFFs, (png_const_structrp png_ptr, + png_const_inforp info_ptr, png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type)); #endif -#if defined(PNG_oFFs_SUPPORTED) -extern PNG_EXPORT(void,png_set_oFFs) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_int_32 offset_x, png_int_32 offset_y, - int unit_type)); +#ifdef PNG_oFFs_SUPPORTED +PNG_EXPORT(146, void, png_set_oFFs, (png_const_structrp png_ptr, + png_inforp info_ptr, png_int_32 offset_x, png_int_32 offset_y, + int unit_type)); #endif -#if defined(PNG_pCAL_SUPPORTED) -extern PNG_EXPORT(png_uint_32,png_get_pCAL) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_charp *purpose, png_int_32 *X0, png_int_32 *X1, - int *type, int *nparams, png_charp *units, png_charpp *params)); +#ifdef PNG_pCAL_SUPPORTED +PNG_EXPORT(147, png_uint_32, png_get_pCAL, (png_const_structrp png_ptr, + png_inforp info_ptr, png_charp *purpose, png_int_32 *X0, + png_int_32 *X1, int *type, int *nparams, png_charp *units, + png_charpp *params)); #endif -#if defined(PNG_pCAL_SUPPORTED) -extern PNG_EXPORT(void,png_set_pCAL) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1, - int type, int nparams, png_charp units, png_charpp params)); +#ifdef PNG_pCAL_SUPPORTED +PNG_EXPORT(148, void, png_set_pCAL, (png_const_structrp png_ptr, + png_inforp info_ptr, png_const_charp purpose, png_int_32 X0, png_int_32 X1, + int type, int nparams, png_const_charp units, png_charpp params)); #endif -#if defined(PNG_pHYs_SUPPORTED) -extern PNG_EXPORT(png_uint_32,png_get_pHYs) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)); +#ifdef PNG_pHYs_SUPPORTED +PNG_EXPORT(149, png_uint_32, png_get_pHYs, (png_const_structrp png_ptr, + png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, + int *unit_type)); #endif -#if defined(PNG_pHYs_SUPPORTED) -extern PNG_EXPORT(void,png_set_pHYs) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type)); +#ifdef PNG_pHYs_SUPPORTED +PNG_EXPORT(150, void, png_set_pHYs, (png_const_structrp png_ptr, + png_inforp info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type)); #endif -extern PNG_EXPORT(png_uint_32,png_get_PLTE) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_colorp *palette, int *num_palette)); +PNG_EXPORT(151, png_uint_32, png_get_PLTE, (png_const_structrp png_ptr, + png_inforp info_ptr, png_colorp *palette, int *num_palette)); -extern PNG_EXPORT(void,png_set_PLTE) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_colorp palette, int num_palette)); +PNG_EXPORT(152, void, png_set_PLTE, (png_structrp png_ptr, + png_inforp info_ptr, png_const_colorp palette, int num_palette)); -#if defined(PNG_sBIT_SUPPORTED) -extern PNG_EXPORT(png_uint_32,png_get_sBIT) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_color_8p *sig_bit)); +#ifdef PNG_sBIT_SUPPORTED +PNG_EXPORT(153, png_uint_32, png_get_sBIT, (png_const_structrp png_ptr, + png_inforp info_ptr, png_color_8p *sig_bit)); #endif -#if defined(PNG_sBIT_SUPPORTED) -extern PNG_EXPORT(void,png_set_sBIT) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_color_8p sig_bit)); +#ifdef PNG_sBIT_SUPPORTED +PNG_EXPORT(154, void, png_set_sBIT, (png_const_structrp png_ptr, + png_inforp info_ptr, png_const_color_8p sig_bit)); #endif -#if defined(PNG_sRGB_SUPPORTED) -extern PNG_EXPORT(png_uint_32,png_get_sRGB) PNGARG((png_structp png_ptr, - png_infop info_ptr, int *intent)); +#ifdef PNG_sRGB_SUPPORTED +PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structrp png_ptr, + png_const_inforp info_ptr, int *file_srgb_intent)); #endif -#if defined(PNG_sRGB_SUPPORTED) -extern PNG_EXPORT(void,png_set_sRGB) PNGARG((png_structp png_ptr, - png_infop info_ptr, int intent)); -extern PNG_EXPORT(void,png_set_sRGB_gAMA_and_cHRM) PNGARG((png_structp png_ptr, - png_infop info_ptr, int intent)); +#ifdef PNG_sRGB_SUPPORTED +PNG_EXPORT(156, void, png_set_sRGB, (png_const_structrp png_ptr, + png_inforp info_ptr, int srgb_intent)); +PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_const_structrp png_ptr, + png_inforp info_ptr, int srgb_intent)); #endif -#if defined(PNG_iCCP_SUPPORTED) -extern PNG_EXPORT(png_uint_32,png_get_iCCP) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_charpp name, int *compression_type, - png_charpp profile, png_uint_32 *proflen)); - /* Note to maintainer: profile should be png_bytepp */ +#ifdef PNG_iCCP_SUPPORTED +PNG_EXPORT(158, png_uint_32, png_get_iCCP, (png_const_structrp png_ptr, + png_inforp info_ptr, png_charpp name, int *compression_type, + png_bytepp profile, png_uint_32 *proflen)); #endif -#if defined(PNG_iCCP_SUPPORTED) -extern PNG_EXPORT(void,png_set_iCCP) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_charp name, int compression_type, - png_charp profile, png_uint_32 proflen)); - /* Note to maintainer: profile should be png_bytep */ +#ifdef PNG_iCCP_SUPPORTED +PNG_EXPORT(159, void, png_set_iCCP, (png_const_structrp png_ptr, + png_inforp info_ptr, png_const_charp name, int compression_type, + png_const_bytep profile, png_uint_32 proflen)); #endif -#if defined(PNG_sPLT_SUPPORTED) -extern PNG_EXPORT(png_uint_32,png_get_sPLT) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_sPLT_tpp entries)); +#ifdef PNG_sPLT_SUPPORTED +PNG_EXPORT(160, int, png_get_sPLT, (png_const_structrp png_ptr, + png_inforp info_ptr, png_sPLT_tpp entries)); #endif -#if defined(PNG_sPLT_SUPPORTED) -extern PNG_EXPORT(void,png_set_sPLT) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_sPLT_tp entries, int nentries)); +#ifdef PNG_sPLT_SUPPORTED +PNG_EXPORT(161, void, png_set_sPLT, (png_const_structrp png_ptr, + png_inforp info_ptr, png_const_sPLT_tp entries, int nentries)); #endif -#if defined(PNG_TEXT_SUPPORTED) +#ifdef PNG_TEXT_SUPPORTED /* png_get_text also returns the number of text chunks in *num_text */ -extern PNG_EXPORT(png_uint_32,png_get_text) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_textp *text_ptr, int *num_text)); +PNG_EXPORT(162, int, png_get_text, (png_const_structrp png_ptr, + png_inforp info_ptr, png_textp *text_ptr, int *num_text)); #endif -/* - * Note while png_set_text() will accept a structure whose text, - * language, and translated keywords are NULL pointers, the structure - * returned by png_get_text will always contain regular - * zero-terminated C strings. They might be empty strings but - * they will never be NULL pointers. +/* Note while png_set_text() will accept a structure whose text, + * language, and translated keywords are NULL pointers, the structure + * returned by png_get_text will always contain regular + * zero-terminated C strings. They might be empty strings but + * they will never be NULL pointers. */ -#if defined(PNG_TEXT_SUPPORTED) -extern PNG_EXPORT(void,png_set_text) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_textp text_ptr, int num_text)); -#endif - -#if defined(PNG_tIME_SUPPORTED) -extern PNG_EXPORT(png_uint_32,png_get_tIME) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_timep *mod_time)); +#ifdef PNG_TEXT_SUPPORTED +PNG_EXPORT(163, void, png_set_text, (png_const_structrp png_ptr, + png_inforp info_ptr, png_const_textp text_ptr, int num_text)); #endif -#if defined(PNG_tIME_SUPPORTED) -extern PNG_EXPORT(void,png_set_tIME) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_timep mod_time)); +#ifdef PNG_tIME_SUPPORTED +PNG_EXPORT(164, png_uint_32, png_get_tIME, (png_const_structrp png_ptr, + png_inforp info_ptr, png_timep *mod_time)); #endif -#if defined(PNG_tRNS_SUPPORTED) -extern PNG_EXPORT(png_uint_32,png_get_tRNS) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_bytep *trans, int *num_trans, - png_color_16p *trans_values)); +#ifdef PNG_tIME_SUPPORTED +PNG_EXPORT(165, void, png_set_tIME, (png_const_structrp png_ptr, + png_inforp info_ptr, png_const_timep mod_time)); #endif -#if defined(PNG_tRNS_SUPPORTED) -extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_bytep trans, int num_trans, - png_color_16p trans_values)); +#ifdef PNG_tRNS_SUPPORTED +PNG_EXPORT(166, png_uint_32, png_get_tRNS, (png_const_structrp png_ptr, + png_inforp info_ptr, png_bytep *trans_alpha, int *num_trans, + png_color_16p *trans_color)); #endif -#if defined(PNG_tRNS_SUPPORTED) +#ifdef PNG_tRNS_SUPPORTED +PNG_EXPORT(167, void, png_set_tRNS, (png_structrp png_ptr, + png_inforp info_ptr, png_const_bytep trans_alpha, int num_trans, + png_const_color_16p trans_color)); #endif -#if defined(PNG_sCAL_SUPPORTED) -#ifdef PNG_FLOATING_POINT_SUPPORTED -extern PNG_EXPORT(png_uint_32,png_get_sCAL) PNGARG((png_structp png_ptr, - png_infop info_ptr, int *unit, double *width, double *height)); -#else -#ifdef PNG_FIXED_POINT_SUPPORTED -extern PNG_EXPORT(png_uint_32,png_get_sCAL_s) PNGARG((png_structp png_ptr, - png_infop info_ptr, int *unit, png_charpp swidth, png_charpp sheight)); -#endif -#endif +#ifdef PNG_sCAL_SUPPORTED +PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL, (png_const_structrp png_ptr, + png_const_inforp info_ptr, int *unit, double *width, double *height)) +#if defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) || \ + defined(PNG_FLOATING_POINT_SUPPORTED) +/* NOTE: this API is currently implemented using floating point arithmetic, + * consequently it can only be used on systems with floating point support. + * In any case the range of values supported by png_fixed_point is small and it + * is highly recommended that png_get_sCAL_s be used instead. + */ +PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed, + (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit, + png_fixed_point *width, png_fixed_point *height)) +#endif +PNG_EXPORT(169, png_uint_32, png_get_sCAL_s, + (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit, + png_charpp swidth, png_charpp sheight)); + +PNG_FP_EXPORT(170, void, png_set_sCAL, (png_const_structrp png_ptr, + png_inforp info_ptr, int unit, double width, double height)) +PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_const_structrp png_ptr, + png_inforp info_ptr, int unit, png_fixed_point width, + png_fixed_point height)) +PNG_EXPORT(171, void, png_set_sCAL_s, (png_const_structrp png_ptr, + png_inforp info_ptr, int unit, + png_const_charp swidth, png_const_charp sheight)); #endif /* PNG_sCAL_SUPPORTED */ -#if defined(PNG_sCAL_SUPPORTED) -#ifdef PNG_FLOATING_POINT_SUPPORTED -extern PNG_EXPORT(void,png_set_sCAL) PNGARG((png_structp png_ptr, - png_infop info_ptr, int unit, double width, double height)); -#endif -#ifdef PNG_FIXED_POINT_SUPPORTED -extern PNG_EXPORT(void,png_set_sCAL_s) PNGARG((png_structp png_ptr, - png_infop info_ptr, int unit, png_charp swidth, png_charp sheight)); -#endif -#endif /* PNG_sCAL_SUPPORTED || PNG_WRITE_sCAL_SUPPORTED */ - -#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) -/* provide a list of chunks and how they are to be handled, if the built-in - handling or default unknown chunk handling is not desired. Any chunks not - listed will be handled in the default manner. The IHDR and IEND chunks - must not be listed. - keep = 0: follow default behavour - = 1: do not keep - = 2: keep only if safe-to-copy - = 3: keep even if unsafe-to-copy -*/ -extern PNG_EXPORT(void, png_set_keep_unknown_chunks) PNGARG((png_structp - png_ptr, int keep, png_bytep chunk_list, int num_chunks)); -extern PNG_EXPORT(void, png_set_unknown_chunks) PNGARG((png_structp png_ptr, - png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns)); -extern PNG_EXPORT(void, png_set_unknown_chunk_location) - PNGARG((png_structp png_ptr, png_infop info_ptr, int chunk, int location)); -extern PNG_EXPORT(png_uint_32,png_get_unknown_chunks) PNGARG((png_structp - png_ptr, png_infop info_ptr, png_unknown_chunkpp entries)); -#endif -#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED -PNG_EXPORT(int,png_handle_as_unknown) PNGARG((png_structp png_ptr, png_bytep - chunk_name)); +#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED +/* Provide the default handling for all unknown chunks or, optionally, for + * specific unknown chunks. + * + * NOTE: prior to 1.6.0 the handling specified for particular chunks on read was + * ignored and the default was used, the per-chunk setting only had an effect on + * write. If you wish to have chunk-specific handling on read in code that must + * work on earlier versions you must use a user chunk callback to specify the + * desired handling (keep or discard.) + * + * The 'keep' parameter is a PNG_HANDLE_CHUNK_ value as listed below. The + * parameter is interpreted as follows: + * + * READ: + * PNG_HANDLE_CHUNK_AS_DEFAULT: + * Known chunks: do normal libpng processing, do not keep the chunk (but + * see the comments below about PNG_HANDLE_AS_UNKNOWN_SUPPORTED) + * Unknown chunks: for a specific chunk use the global default, when used + * as the default discard the chunk data. + * PNG_HANDLE_CHUNK_NEVER: + * Discard the chunk data. + * PNG_HANDLE_CHUNK_IF_SAFE: + * Keep the chunk data if the chunk is not critical else raise a chunk + * error. + * PNG_HANDLE_CHUNK_ALWAYS: + * Keep the chunk data. + * + * If the chunk data is saved it can be retrieved using png_get_unknown_chunks, + * below. Notice that specifying "AS_DEFAULT" as a global default is equivalent + * to specifying "NEVER", however when "AS_DEFAULT" is used for specific chunks + * it simply resets the behavior to the libpng default. + * + * INTERACTION WTIH USER CHUNK CALLBACKS: + * The per-chunk handling is always used when there is a png_user_chunk_ptr + * callback and the callback returns 0; the chunk is then always stored *unless* + * it is critical and the per-chunk setting is other than ALWAYS. Notice that + * the global default is *not* used in this case. (In effect the per-chunk + * value is incremented to at least IF_SAFE.) + * + * IMPORTANT NOTE: this behavior will change in libpng 1.7 - the global and + * per-chunk defaults will be honored. If you want to preserve the current + * behavior when your callback returns 0 you must set PNG_HANDLE_CHUNK_IF_SAFE + * as the default - if you don't do this libpng 1.6 will issue a warning. + * + * If you want unhandled unknown chunks to be discarded in libpng 1.6 and + * earlier simply return '1' (handled). + * + * PNG_HANDLE_AS_UNKNOWN_SUPPORTED: + * If this is *not* set known chunks will always be handled by libpng and + * will never be stored in the unknown chunk list. Known chunks listed to + * png_set_keep_unknown_chunks will have no effect. If it is set then known + * chunks listed with a keep other than AS_DEFAULT will *never* be processed + * by libpng, in addition critical chunks must either be processed by the + * callback or saved. + * + * The IHDR and IEND chunks must not be listed. Because this turns off the + * default handling for chunks that would otherwise be recognized the + * behavior of libpng transformations may well become incorrect! + * + * WRITE: + * When writing chunks the options only apply to the chunks specified by + * png_set_unknown_chunks (below), libpng will *always* write known chunks + * required by png_set_ calls and will always write the core critical chunks + * (as required for PLTE). + * + * Each chunk in the png_set_unknown_chunks list is looked up in the + * png_set_keep_unknown_chunks list to find the keep setting, this is then + * interpreted as follows: + * + * PNG_HANDLE_CHUNK_AS_DEFAULT: + * Write safe-to-copy chunks and write other chunks if the global + * default is set to _ALWAYS, otherwise don't write this chunk. + * PNG_HANDLE_CHUNK_NEVER: + * Do not write the chunk. + * PNG_HANDLE_CHUNK_IF_SAFE: + * Write the chunk if it is safe-to-copy, otherwise do not write it. + * PNG_HANDLE_CHUNK_ALWAYS: + * Write the chunk. + * + * Note that the default behavior is effectively the opposite of the read case - + * in read unknown chunks are not stored by default, in write they are written + * by default. Also the behavior of PNG_HANDLE_CHUNK_IF_SAFE is very different + * - on write the safe-to-copy bit is checked, on read the critical bit is + * checked and on read if the chunk is critical an error will be raised. + * + * num_chunks: + * =========== + * If num_chunks is positive, then the "keep" parameter specifies the manner + * for handling only those chunks appearing in the chunk_list array, + * otherwise the chunk list array is ignored. + * + * If num_chunks is 0 the "keep" parameter specifies the default behavior for + * unknown chunks, as described above. + * + * If num_chunks is negative, then the "keep" parameter specifies the manner + * for handling all unknown chunks plus all chunks recognized by libpng + * except for the IHDR, PLTE, tRNS, IDAT, and IEND chunks (which continue to + * be processed by libpng. + */ +PNG_EXPORT(172, void, png_set_keep_unknown_chunks, (png_structrp png_ptr, + int keep, png_const_bytep chunk_list, int num_chunks)); + +/* The "keep" PNG_HANDLE_CHUNK_ parameter for the specified chunk is returned; + * the result is therefore true (non-zero) if special handling is required, + * false for the default handling. + */ +PNG_EXPORT(173, int, png_handle_as_unknown, (png_const_structrp png_ptr, + png_const_bytep chunk_name)); +#endif + +#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED +PNG_EXPORT(174, void, png_set_unknown_chunks, (png_const_structrp png_ptr, + png_inforp info_ptr, png_const_unknown_chunkp unknowns, + int num_unknowns)); + /* NOTE: prior to 1.6.0 this routine set the 'location' field of the added + * unknowns to the location currently stored in the png_struct. This is + * invariably the wrong value on write. To fix this call the following API + * for each chunk in the list with the correct location. If you know your + * code won't be compiled on earlier versions you can rely on + * png_set_unknown_chunks(write-ptr, png_get_unknown_chunks(read-ptr)) doing + * the correct thing. + */ + +PNG_EXPORT(175, void, png_set_unknown_chunk_location, + (png_const_structrp png_ptr, png_inforp info_ptr, int chunk, int location)); + +PNG_EXPORT(176, int, png_get_unknown_chunks, (png_const_structrp png_ptr, + png_inforp info_ptr, png_unknown_chunkpp entries)); #endif /* Png_free_data() will turn off the "valid" flag for anything it frees. - If you need to turn it off for a chunk that your application has freed, - you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); */ -extern PNG_EXPORT(void, png_set_invalid) PNGARG((png_structp png_ptr, - png_infop info_ptr, int mask)); + * If you need to turn it off for a chunk that your application has freed, + * you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); + */ +PNG_EXPORT(177, void, png_set_invalid, (png_const_structrp png_ptr, + png_inforp info_ptr, int mask)); -#if defined(PNG_INFO_IMAGE_SUPPORTED) +#ifdef PNG_INFO_IMAGE_SUPPORTED /* The "params" pointer is currently not used and is for future expansion. */ -extern PNG_EXPORT(void, png_read_png) PNGARG((png_structp png_ptr, - png_infop info_ptr, - int transforms, - png_voidp params)); -extern PNG_EXPORT(void, png_write_png) PNGARG((png_structp png_ptr, - png_infop info_ptr, - int transforms, - png_voidp params)); -#endif - -/* Define PNG_DEBUG at compile time for debugging information. Higher - * numbers for PNG_DEBUG mean more debugging information. This has - * only been added since version 0.95 so it is not implemented throughout - * libpng yet, but more support will be added as needed. - */ -#ifdef PNG_DEBUG -#if (PNG_DEBUG > 0) -#if !defined(PNG_DEBUG_FILE) && defined(_MSC_VER) -#include -#if (PNG_DEBUG > 1) -#define png_debug(l,m) _RPT0(_CRT_WARN,m) -#define png_debug1(l,m,p1) _RPT1(_CRT_WARN,m,p1) -#define png_debug2(l,m,p1,p2) _RPT2(_CRT_WARN,m,p1,p2) -#endif -#else /* PNG_DEBUG_FILE || !_MSC_VER */ -#ifndef PNG_DEBUG_FILE -#define PNG_DEBUG_FILE stderr -#endif /* PNG_DEBUG_FILE */ -#if (PNG_DEBUG > 1) -#define png_debug(l,m) \ -{ \ - int num_tabs=l; \ - fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \ - (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":"")))); \ -} -#define png_debug1(l,m,p1) \ -{ \ - int num_tabs=l; \ - fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \ - (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1); \ -} -#define png_debug2(l,m,p1,p2) \ -{ \ - int num_tabs=l; \ - fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \ - (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1,p2); \ -} -#endif /* (PNG_DEBUG > 1) */ -#endif /* _MSC_VER */ -#endif /* (PNG_DEBUG > 0) */ -#endif /* PNG_DEBUG */ -#ifndef png_debug -#define png_debug(l, m) -#endif -#ifndef png_debug1 -#define png_debug1(l, m, p1) -#endif -#ifndef png_debug2 -#define png_debug2(l, m, p1, p2) +PNG_EXPORT(178, void, png_read_png, (png_structrp png_ptr, png_inforp info_ptr, + int transforms, png_voidp params)); +PNG_EXPORT(179, void, png_write_png, (png_structrp png_ptr, png_inforp info_ptr, + int transforms, png_voidp params)); #endif -extern PNG_EXPORT(png_bytep,png_sig_bytes) PNGARG((void)); - -extern PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr)); -extern PNG_EXPORT(png_charp,png_get_header_ver) PNGARG((png_structp png_ptr)); -extern PNG_EXPORT(png_charp,png_get_header_version) PNGARG((png_structp png_ptr)); -extern PNG_EXPORT(png_charp,png_get_libpng_ver) PNGARG((png_structp png_ptr)); +PNG_EXPORT(180, png_const_charp, png_get_copyright, + (png_const_structrp png_ptr)); +PNG_EXPORT(181, png_const_charp, png_get_header_ver, + (png_const_structrp png_ptr)); +PNG_EXPORT(182, png_const_charp, png_get_header_version, + (png_const_structrp png_ptr)); +PNG_EXPORT(183, png_const_charp, png_get_libpng_ver, + (png_const_structrp png_ptr)); #ifdef PNG_MNG_FEATURES_SUPPORTED -extern PNG_EXPORT(png_uint_32,png_permit_mng_features) PNGARG((png_structp - png_ptr, png_uint_32 mng_features_permitted)); -#endif - -/* Added to version 1.2.0 */ -#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) -#define PNG_ASM_FLAG_MMX_SUPPORT_COMPILED 0x01 /* not user-settable */ -#define PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU 0x02 /* not user-settable */ -#define PNG_ASM_FLAG_MMX_READ_COMBINE_ROW 0x04 -#define PNG_ASM_FLAG_MMX_READ_INTERLACE 0x08 -#define PNG_ASM_FLAG_MMX_READ_FILTER_SUB 0x10 -#define PNG_ASM_FLAG_MMX_READ_FILTER_UP 0x20 -#define PNG_ASM_FLAG_MMX_READ_FILTER_AVG 0x40 -#define PNG_ASM_FLAG_MMX_READ_FILTER_PAETH 0x80 -#define PNG_ASM_FLAGS_INITIALIZED 0x80000000 /* not user-settable */ - -#define PNG_MMX_READ_FLAGS ( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW \ - | PNG_ASM_FLAG_MMX_READ_INTERLACE \ - | PNG_ASM_FLAG_MMX_READ_FILTER_SUB \ - | PNG_ASM_FLAG_MMX_READ_FILTER_UP \ - | PNG_ASM_FLAG_MMX_READ_FILTER_AVG \ - | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH ) -#define PNG_MMX_WRITE_FLAGS ( 0 ) - -#define PNG_MMX_FLAGS ( PNG_ASM_FLAG_MMX_SUPPORT_COMPILED \ - | PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU \ - | PNG_MMX_READ_FLAGS \ - | PNG_MMX_WRITE_FLAGS ) - -#define PNG_SELECT_READ 1 -#define PNG_SELECT_WRITE 2 - - -#if !defined(PNG_1_0_X) -/* pngget.c */ -extern PNG_EXPORT(png_uint_32,png_get_mmx_flagmask) - PNGARG((int flag_select, int *compilerID)); - -/* pngget.c */ -extern PNG_EXPORT(png_uint_32,png_get_asm_flagmask) - PNGARG((int flag_select)); - -/* pngget.c */ -extern PNG_EXPORT(png_uint_32,png_get_asm_flags) - PNGARG((png_structp png_ptr)); - -/* pngget.c */ -extern PNG_EXPORT(png_byte,png_get_mmx_bitdepth_threshold) - PNGARG((png_structp png_ptr)); - -/* pngget.c */ -extern PNG_EXPORT(png_uint_32,png_get_mmx_rowbytes_threshold) - PNGARG((png_structp png_ptr)); - -/* pngset.c */ -extern PNG_EXPORT(void,png_set_asm_flags) - PNGARG((png_structp png_ptr, png_uint_32 asm_flags)); - -/* pngset.c */ -extern PNG_EXPORT(void,png_set_mmx_thresholds) - PNGARG((png_structp png_ptr, png_byte mmx_bitdepth_threshold, - png_uint_32 mmx_rowbytes_threshold)); - -#endif /* PNG_1_0_X */ -#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */ - -#if !defined(PNG_1_0_X) -/* png.c, pnggccrd.c, or pngvcrd.c */ -extern PNG_EXPORT(int,png_mmx_support) PNGARG((void)); +PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structrp png_ptr, + png_uint_32 mng_features_permitted)); +#endif + +/* For use in png_set_keep_unknown, added to version 1.2.6 */ +#define PNG_HANDLE_CHUNK_AS_DEFAULT 0 +#define PNG_HANDLE_CHUNK_NEVER 1 +#define PNG_HANDLE_CHUNK_IF_SAFE 2 +#define PNG_HANDLE_CHUNK_ALWAYS 3 +#define PNG_HANDLE_CHUNK_LAST 4 /* Strip the prepended error numbers ("#nnn ") from error and warning - * messages before passing them to the error or warning handler. */ + * messages before passing them to the error or warning handler. + */ #ifdef PNG_ERROR_NUMBERS_SUPPORTED -extern PNG_EXPORT(void,png_set_strip_error_numbers) PNGARG((png_structp - png_ptr, png_uint_32 strip_mode)); -#endif -#endif /* PNG_1_0_X */ +PNG_EXPORT(185, void, png_set_strip_error_numbers, (png_structrp png_ptr, + png_uint_32 strip_mode)); +#endif + +/* Added in libpng-1.2.6 */ +#ifdef PNG_SET_USER_LIMITS_SUPPORTED +PNG_EXPORT(186, void, png_set_user_limits, (png_structrp png_ptr, + png_uint_32 user_width_max, png_uint_32 user_height_max)); +PNG_EXPORT(187, png_uint_32, png_get_user_width_max, + (png_const_structrp png_ptr)); +PNG_EXPORT(188, png_uint_32, png_get_user_height_max, + (png_const_structrp png_ptr)); +/* Added in libpng-1.4.0 */ +PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structrp png_ptr, + png_uint_32 user_chunk_cache_max)); +PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max, + (png_const_structrp png_ptr)); +/* Added in libpng-1.4.1 */ +PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structrp png_ptr, + png_alloc_size_t user_chunk_cache_max)); +PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max, + (png_const_structrp png_ptr)); +#endif + +#if defined(PNG_INCH_CONVERSIONS_SUPPORTED) +PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch, + (png_const_structrp png_ptr, png_const_inforp info_ptr)); + +PNG_EXPORT(194, png_uint_32, png_get_x_pixels_per_inch, + (png_const_structrp png_ptr, png_const_inforp info_ptr)); + +PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch, + (png_const_structrp png_ptr, png_const_inforp info_ptr)); + +PNG_FP_EXPORT(196, float, png_get_x_offset_inches, + (png_const_structrp png_ptr, png_const_inforp info_ptr)) +#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ +PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed, + (png_const_structrp png_ptr, png_const_inforp info_ptr)) +#endif + +PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structrp png_ptr, + png_const_inforp info_ptr)) +#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ +PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed, + (png_const_structrp png_ptr, png_const_inforp info_ptr)) +#endif + +# ifdef PNG_pHYs_SUPPORTED +PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structrp png_ptr, + png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, + int *unit_type)); +# endif /* PNG_pHYs_SUPPORTED */ +#endif /* PNG_INCH_CONVERSIONS_SUPPORTED */ + +/* Added in libpng-1.4.0 */ +#ifdef PNG_IO_STATE_SUPPORTED +PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_const_structrp png_ptr)); + +/* Removed from libpng 1.6; use png_get_io_chunk_type. */ +PNG_REMOVED(200, png_const_bytep, png_get_io_chunk_name, (png_structrp png_ptr), + PNG_DEPRECATED) + +PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type, + (png_const_structrp png_ptr)); + +/* The flags returned by png_get_io_state() are the following: */ +# define PNG_IO_NONE 0x0000 /* no I/O at this moment */ +# define PNG_IO_READING 0x0001 /* currently reading */ +# define PNG_IO_WRITING 0x0002 /* currently writing */ +# define PNG_IO_SIGNATURE 0x0010 /* currently at the file signature */ +# define PNG_IO_CHUNK_HDR 0x0020 /* currently at the chunk header */ +# define PNG_IO_CHUNK_DATA 0x0040 /* currently at the chunk data */ +# define PNG_IO_CHUNK_CRC 0x0080 /* currently at the chunk crc */ +# define PNG_IO_MASK_OP 0x000f /* current operation: reading/writing */ +# define PNG_IO_MASK_LOC 0x00f0 /* current location: sig/hdr/data/crc */ +#endif /* ?PNG_IO_STATE_SUPPORTED */ + +/* Interlace support. The following macros are always defined so that if + * libpng interlace handling is turned off the macros may be used to handle + * interlaced images within the application. + */ +#define PNG_INTERLACE_ADAM7_PASSES 7 -/* Maintainer: Put new public prototypes here ^, in libpng.3, and project defs */ +/* Two macros to return the first row and first column of the original, + * full, image which appears in a given pass. 'pass' is in the range 0 + * to 6 and the result is in the range 0 to 7. + */ +#define PNG_PASS_START_ROW(pass) (((1&~(pass))<<(3-((pass)>>1)))&7) +#define PNG_PASS_START_COL(pass) (((1& (pass))<<(3-(((pass)+1)>>1)))&7) -#define PNG_HEADER_VERSION_STRING \ - " libpng version 1.2.4 - July 8, 2002 (header)\n" +/* A macro to return the offset between pixels in the output row for a pair of + * pixels in the input - effectively the inverse of the 'COL_SHIFT' macro that + * follows. Note that ROW_OFFSET is the offset from one row to the next whereas + * COL_OFFSET is from one column to the next, within a row. + */ +#define PNG_PASS_ROW_OFFSET(pass) ((pass)>2?(8>>(((pass)-1)>>1)):8) +#define PNG_PASS_COL_OFFSET(pass) (1<<((7-(pass))>>1)) + +/* Two macros to help evaluate the number of rows or columns in each + * pass. This is expressed as a shift - effectively log2 of the number or + * rows or columns in each 8x8 tile of the original image. + */ +#define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3) +#define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3) + +/* Hence two macros to determine the number of rows or columns in a given + * pass of an image given its height or width. In fact these macros may + * return non-zero even though the sub-image is empty, because the other + * dimension may be empty for a small image. + */ +#define PNG_PASS_ROWS(height, pass) (((height)+(((1<>PNG_PASS_ROW_SHIFT(pass)) +#define PNG_PASS_COLS(width, pass) (((width)+(((1<>PNG_PASS_COL_SHIFT(pass)) + +/* For the reader row callbacks (both progressive and sequential) it is + * necessary to find the row in the output image given a row in an interlaced + * image, so two more macros: + */ +#define PNG_ROW_FROM_PASS_ROW(y_in, pass) \ + (((y_in)<>(((7-(off))-(pass))<<2)) & 0xF) | \ + ((0x01145AF0>>(((7-(off))-(pass))<<2)) & 0xF0)) + +#define PNG_ROW_IN_INTERLACE_PASS(y, pass) \ + ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1) +#define PNG_COL_IN_INTERLACE_PASS(x, pass) \ + ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1) #ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED /* With these routines we avoid an integer divide, which will be slower on @@ -2436,843 +2685,620 @@ extern PNG_EXPORT(void,png_set_strip_error_numbers) PNGARG((png_structp * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ] */ - /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */ + /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */ -# define png_composite(composite, fg, alpha, bg) \ - { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) * (png_uint_16)(alpha) \ - + (png_uint_16)(bg)*(png_uint_16)(255 - \ - (png_uint_16)(alpha)) + (png_uint_16)128); \ +# define png_composite(composite, fg, alpha, bg) \ + { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \ + * (png_uint_16)(alpha) \ + + (png_uint_16)(bg)*(png_uint_16)(255 \ + - (png_uint_16)(alpha)) + 128); \ (composite) = (png_byte)((temp + (temp >> 8)) >> 8); } -# define png_composite_16(composite, fg, alpha, bg) \ - { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) * (png_uint_32)(alpha) \ - + (png_uint_32)(bg)*(png_uint_32)(65535L - \ - (png_uint_32)(alpha)) + (png_uint_32)32768L); \ +# define png_composite_16(composite, fg, alpha, bg) \ + { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) \ + * (png_uint_32)(alpha) \ + + (png_uint_32)(bg)*(65535 \ + - (png_uint_32)(alpha)) + 32768); \ (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); } -#else /* standard method using integer division */ +#else /* Standard method using integer division */ -# define png_composite(composite, fg, alpha, bg) \ - (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \ - (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \ - (png_uint_16)127) / 255) +# define png_composite(composite, fg, alpha, bg) \ + (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \ + (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \ + 127) / 255) # define png_composite_16(composite, fg, alpha, bg) \ (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \ - (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) + \ - (png_uint_32)32767) / (png_uint_32)65535L) - + (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) + \ + 32767) / 65535) #endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */ -/* These next functions are used internally in the code. They generally - * shouldn't be used unless you are writing code to add or replace some - * functionality in libpng. More information about most functions can - * be found in the files where the functions are located. - */ - -#if defined(PNG_INTERNAL) - -/* Various modes of operation. Note that after an init, mode is set to - * zero automatically when the structure is created. - */ -#define PNG_HAVE_IHDR 0x01 -#define PNG_HAVE_PLTE 0x02 -#define PNG_HAVE_IDAT 0x04 -#define PNG_AFTER_IDAT 0x08 -#define PNG_HAVE_IEND 0x10 -#define PNG_HAVE_gAMA 0x20 -#define PNG_HAVE_cHRM 0x40 -#define PNG_HAVE_sRGB 0x80 -#define PNG_HAVE_CHUNK_HEADER 0x100 -#define PNG_WROTE_tIME 0x200 -#define PNG_WROTE_INFO_BEFORE_PLTE 0x400 -#define PNG_BACKGROUND_IS_GRAY 0x800 -#define PNG_HAVE_PNG_SIGNATURE 0x1000 - -/* flags for the transformations the PNG library does on the image data */ -#define PNG_BGR 0x0001 -#define PNG_INTERLACE 0x0002 -#define PNG_PACK 0x0004 -#define PNG_SHIFT 0x0008 -#define PNG_SWAP_BYTES 0x0010 -#define PNG_INVERT_MONO 0x0020 -#define PNG_DITHER 0x0040 -#define PNG_BACKGROUND 0x0080 -#define PNG_BACKGROUND_EXPAND 0x0100 - /* 0x0200 unused */ -#define PNG_16_TO_8 0x0400 -#define PNG_RGBA 0x0800 -#define PNG_EXPAND 0x1000 -#define PNG_GAMMA 0x2000 -#define PNG_GRAY_TO_RGB 0x4000 -#define PNG_FILLER 0x8000L -#define PNG_PACKSWAP 0x10000L -#define PNG_SWAP_ALPHA 0x20000L -#define PNG_STRIP_ALPHA 0x40000L -#define PNG_INVERT_ALPHA 0x80000L -#define PNG_USER_TRANSFORM 0x100000L -#define PNG_RGB_TO_GRAY_ERR 0x200000L -#define PNG_RGB_TO_GRAY_WARN 0x400000L -#define PNG_RGB_TO_GRAY 0x600000L /* two bits, RGB_TO_GRAY_ERR|WARN */ - -/* flags for png_create_struct */ -#define PNG_STRUCT_PNG 0x0001 -#define PNG_STRUCT_INFO 0x0002 - -/* Scaling factor for filter heuristic weighting calculations */ -#define PNG_WEIGHT_SHIFT 8 -#define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT)) -#define PNG_COST_SHIFT 3 -#define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT)) - -/* flags for the png_ptr->flags rather than declaring a byte for each one */ -#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001 -#define PNG_FLAG_ZLIB_CUSTOM_LEVEL 0x0002 -#define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL 0x0004 -#define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS 0x0008 -#define PNG_FLAG_ZLIB_CUSTOM_METHOD 0x0010 -#define PNG_FLAG_ZLIB_FINISHED 0x0020 -#define PNG_FLAG_ROW_INIT 0x0040 -#define PNG_FLAG_FILLER_AFTER 0x0080 -#define PNG_FLAG_CRC_ANCILLARY_USE 0x0100 -#define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200 -#define PNG_FLAG_CRC_CRITICAL_USE 0x0400 -#define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800 -#define PNG_FLAG_FREE_PLTE 0x1000 -#define PNG_FLAG_FREE_TRNS 0x2000 -#define PNG_FLAG_FREE_HIST 0x4000 -#define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000L -#define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000L -#define PNG_FLAG_LIBRARY_MISMATCH 0x20000L -#define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000L -#define PNG_FLAG_STRIP_ERROR_TEXT 0x80000L -#define PNG_FLAG_MALLOC_NULL_MEM_OK 0x100000L - -/* For use in png_set_keep_unknown, png_handle_as_unknown */ -#define HANDLE_CHUNK_AS_DEFAULT 0 -#define HANDLE_CHUNK_NEVER 1 -#define HANDLE_CHUNK_IF_SAFE 2 -#define HANDLE_CHUNK_ALWAYS 3 - -#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \ - PNG_FLAG_CRC_ANCILLARY_NOWARN) - -#define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \ - PNG_FLAG_CRC_CRITICAL_IGNORE) - -#define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \ - PNG_FLAG_CRC_CRITICAL_MASK) - -/* save typing and make code easier to understand */ -#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \ - abs((int)((c1).green) - (int)((c2).green)) + \ - abs((int)((c1).blue) - (int)((c2).blue))) - -/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */ -#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN) -/* place to hold the signature string for a PNG file. */ -#ifdef PNG_USE_GLOBAL_ARRAYS - PNG_EXPORT_VAR (const png_byte FARDATA) png_sig[8]; -#else -#define png_sig png_sig_bytes(NULL) -#endif -#endif /* PNG_NO_EXTERN */ - -/* Constant strings for known chunk types. If you need to add a chunk, - * define the name here, and add an invocation of the macro in png.c and - * wherever it's needed. - */ -#define PNG_IHDR const png_byte png_IHDR[5] = { 73, 72, 68, 82, '\0'} -#define PNG_IDAT const png_byte png_IDAT[5] = { 73, 68, 65, 84, '\0'} -#define PNG_IEND const png_byte png_IEND[5] = { 73, 69, 78, 68, '\0'} -#define PNG_PLTE const png_byte png_PLTE[5] = { 80, 76, 84, 69, '\0'} -#define PNG_bKGD const png_byte png_bKGD[5] = { 98, 75, 71, 68, '\0'} -#define PNG_cHRM const png_byte png_cHRM[5] = { 99, 72, 82, 77, '\0'} -#define PNG_gAMA const png_byte png_gAMA[5] = {103, 65, 77, 65, '\0'} -#define PNG_hIST const png_byte png_hIST[5] = {104, 73, 83, 84, '\0'} -#define PNG_iCCP const png_byte png_iCCP[5] = {105, 67, 67, 80, '\0'} -#define PNG_iTXt const png_byte png_iTXt[5] = {105, 84, 88, 116, '\0'} -#define PNG_oFFs const png_byte png_oFFs[5] = {111, 70, 70, 115, '\0'} -#define PNG_pCAL const png_byte png_pCAL[5] = {112, 67, 65, 76, '\0'} -#define PNG_sCAL const png_byte png_sCAL[5] = {115, 67, 65, 76, '\0'} -#define PNG_pHYs const png_byte png_pHYs[5] = {112, 72, 89, 115, '\0'} -#define PNG_sBIT const png_byte png_sBIT[5] = {115, 66, 73, 84, '\0'} -#define PNG_sPLT const png_byte png_sPLT[5] = {115, 80, 76, 84, '\0'} -#define PNG_sRGB const png_byte png_sRGB[5] = {115, 82, 71, 66, '\0'} -#define PNG_tEXt const png_byte png_tEXt[5] = {116, 69, 88, 116, '\0'} -#define PNG_tIME const png_byte png_tIME[5] = {116, 73, 77, 69, '\0'} -#define PNG_tRNS const png_byte png_tRNS[5] = {116, 82, 78, 83, '\0'} -#define PNG_zTXt const png_byte png_zTXt[5] = {122, 84, 88, 116, '\0'} - -#ifdef PNG_USE_GLOBAL_ARRAYS -PNG_EXPORT_VAR (const png_byte FARDATA) png_IHDR[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_IDAT[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_IEND[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_PLTE[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_bKGD[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_cHRM[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_gAMA[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_hIST[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_iCCP[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_iTXt[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_oFFs[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_pCAL[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_sCAL[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_pHYs[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_sBIT[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_sPLT[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_sRGB[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_tEXt[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_tIME[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_tRNS[5]; -PNG_EXPORT_VAR (const png_byte FARDATA) png_zTXt[5]; -#endif /* PNG_USE_GLOBAL_ARRAYS */ - - -/* Inline macros to do direct reads of bytes from the input buffer. These - * require that you are using an architecture that uses PNG byte ordering - * (MSB first) and supports unaligned data storage. I think that PowerPC - * in big-endian mode and 680x0 are the only ones that will support this. - * The x86 line of processors definitely do not. The png_get_int_32() - * routine also assumes we are using two's complement format for negative - * values, which is almost certainly true. - */ -#if defined(PNG_READ_BIG_ENDIAN_SUPPORTED) -# if defined(PNG_pCAL_SUPPORTED) || defined(PNG_oFFs_SUPPORTED) -# define png_get_int_32(buf) ( *((png_int_32p) (buf))) -# endif -# define png_get_uint_32(buf) ( *((png_uint_32p) (buf))) -# define png_get_uint_16(buf) ( *((png_uint_16p) (buf))) -#else -# if defined(PNG_pCAL_SUPPORTED) || defined(PNG_oFFs_SUPPORTED) -PNG_EXTERN png_int_32 png_get_int_32 PNGARG((png_bytep buf)); -# endif -PNG_EXTERN png_uint_32 png_get_uint_32 PNGARG((png_bytep buf)); -PNG_EXTERN png_uint_16 png_get_uint_16 PNGARG((png_bytep buf)); -#endif /* !PNG_READ_BIG_ENDIAN_SUPPORTED */ - -/* Initialize png_ptr struct for reading, and allocate any other memory. - * (old interface - DEPRECATED - use png_create_read_struct instead). - */ -extern PNG_EXPORT(void,png_read_init) PNGARG((png_structp png_ptr)); -#undef png_read_init -#define png_read_init(png_ptr) png_read_init_3(&png_ptr, \ - PNG_LIBPNG_VER_STRING, sizeof(png_struct)); -extern PNG_EXPORT(void,png_read_init_3) PNGARG((png_structpp ptr_ptr, - png_const_charp user_png_ver, png_size_t png_struct_size)); -extern PNG_EXPORT(void,png_read_init_2) PNGARG((png_structp png_ptr, - png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t - png_info_size)); - -/* Initialize png_ptr struct for writing, and allocate any other memory. - * (old interface - DEPRECATED - use png_create_write_struct instead). - */ -extern PNG_EXPORT(void,png_write_init) PNGARG((png_structp png_ptr)); -#undef png_write_init -#define png_write_init(png_ptr) png_write_init_3(&png_ptr, \ - PNG_LIBPNG_VER_STRING, sizeof(png_struct)); -extern PNG_EXPORT(void,png_write_init_3) PNGARG((png_structpp ptr_ptr, - png_const_charp user_png_ver, png_size_t png_struct_size)); -extern PNG_EXPORT(void,png_write_init_2) PNGARG((png_structp png_ptr, - png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t - png_info_size)); - -/* Allocate memory for an internal libpng struct */ -PNG_EXTERN png_voidp png_create_struct PNGARG((int type)); - -/* Free memory from internal libpng struct */ -PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr)); - -PNG_EXTERN png_voidp png_create_struct_2 PNGARG((int type, png_malloc_ptr - malloc_fn, png_voidp mem_ptr)); -PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr, - png_free_ptr free_fn, png_voidp mem_ptr)); - -/* Free any memory that info_ptr points to and reset struct. */ -PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr, - png_infop info_ptr)); - -#ifndef PNG_1_0_X -/* Function to allocate memory for zlib. */ -PNG_EXTERN voidpf png_zalloc PNGARG((voidpf png_ptr, uInt items, uInt size)); - -/* Function to free memory for zlib */ -PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr)); - -/* Next four functions are used internally as callbacks. PNGAPI is required - * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3. */ - -PNG_EXTERN void PNGAPI png_default_read_data PNGARG((png_structp png_ptr, - png_bytep data, png_size_t length)); - -#ifdef PNG_PROGRESSIVE_READ_SUPPORTED -PNG_EXTERN void PNGAPI png_push_fill_buffer PNGARG((png_structp png_ptr, - png_bytep buffer, png_size_t length)); +#ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED +PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf)); +PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf)); +PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf)); #endif -PNG_EXTERN void PNGAPI png_default_write_data PNGARG((png_structp png_ptr, - png_bytep data, png_size_t length)); +PNG_EXPORT(204, png_uint_32, png_get_uint_31, (png_const_structrp png_ptr, + png_const_bytep buf)); +/* No png_get_int_16 -- may be added if there's a real need for it. */ -#if defined(PNG_WRITE_FLUSH_SUPPORTED) -#if !defined(PNG_NO_STDIO) -PNG_EXTERN void PNGAPI png_default_flush PNGARG((png_structp png_ptr)); -#endif +/* Place a 32-bit number into a buffer in PNG byte order (big-endian). */ +#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED +PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i)); #endif -#else /* PNG_1_0_X */ -#ifdef PNG_PROGRESSIVE_READ_SUPPORTED -PNG_EXTERN void png_push_fill_buffer PNGARG((png_structp png_ptr, - png_bytep buffer, png_size_t length)); -#endif -#endif /* PNG_1_0_X */ - -/* Reset the CRC variable */ -PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr)); - -/* Write the "data" buffer to whatever output you are using. */ -PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr, png_bytep data, - png_size_t length)); - -/* Read data from whatever input you are using into the "data" buffer */ -PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data, - png_size_t length)); - -/* Read bytes into buf, and update png_ptr->crc */ -PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf, - png_size_t length)); - -/* Decompress data in a chunk that uses compression */ -#if defined(PNG_zTXt_SUPPORTED) || defined(PNG_iTXt_SUPPORTED) || \ - defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) -PNG_EXTERN png_charp png_decompress_chunk PNGARG((png_structp png_ptr, - int comp_type, png_charp chunkdata, png_size_t chunklength, - png_size_t prefix_length, png_size_t *data_length)); -#endif - -/* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */ -PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip)); - -/* Read the CRC from the file and compare it to the libpng calculated CRC */ -PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr)); - -/* Calculate the CRC over a section of data. Note that we are only - * passing a maximum of 64K on systems that have this as a memory limit, - * since this is the maximum buffer size we can specify. - */ -PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr, png_bytep ptr, - png_size_t length)); - -#if defined(PNG_WRITE_FLUSH_SUPPORTED) -PNG_EXTERN void png_flush PNGARG((png_structp png_ptr)); -#endif - - -/* Place a 32-bit number into a buffer in PNG byte order (big-endian). - * The only currently known PNG chunks that use signed numbers are - * the ancillary extension chunks, oFFs and pCAL. - */ -PNG_EXTERN void png_save_uint_32 PNGARG((png_bytep buf, png_uint_32 i)); - -#if defined(PNG_WRITE_pCAL_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED) -PNG_EXTERN void png_save_int_32 PNGARG((png_bytep buf, png_int_32 i)); +#ifdef PNG_SAVE_INT_32_SUPPORTED +PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i)); #endif /* Place a 16-bit number into a buffer in PNG byte order. * The parameter is declared unsigned int, not png_uint_16, * just to avoid potential problems on pre-ANSI C compilers. */ -PNG_EXTERN void png_save_uint_16 PNGARG((png_bytep buf, unsigned int i)); - -/* simple function to write the signature */ -PNG_EXTERN void png_write_sig PNGARG((png_structp png_ptr)); - -/* write various chunks */ - -/* Write the IHDR chunk, and update the png_struct with the necessary - * information. - */ -PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width, - png_uint_32 height, - int bit_depth, int color_type, int compression_method, int filter_method, - int interlace_method)); - -PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr, png_colorp palette, - png_uint_32 num_pal)); - -PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data, - png_size_t length)); - -PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr)); - -#if defined(PNG_WRITE_gAMA_SUPPORTED) -#ifdef PNG_FLOATING_POINT_SUPPORTED -PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma)); -#endif -#ifdef PNG_FIXED_POINT_SUPPORTED -PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr, png_fixed_point - file_gamma)); -#endif +#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED +PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i)); +/* No png_save_int_16 -- may be added if there's a real need for it. */ #endif -#if defined(PNG_WRITE_sBIT_SUPPORTED) -PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr, png_color_8p sbit, - int color_type)); -#endif - -#if defined(PNG_WRITE_cHRM_SUPPORTED) -#ifdef PNG_FLOATING_POINT_SUPPORTED -PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr, - double white_x, double white_y, - double red_x, double red_y, double green_x, double green_y, - double blue_x, double blue_y)); -#endif -#ifdef PNG_FIXED_POINT_SUPPORTED -PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr, - png_fixed_point int_white_x, png_fixed_point int_white_y, - png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point - int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x, - png_fixed_point int_blue_y)); -#endif -#endif - -#if defined(PNG_WRITE_sRGB_SUPPORTED) -PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr, - int intent)); -#endif - -#if defined(PNG_WRITE_iCCP_SUPPORTED) -PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr, - png_charp name, int compression_type, - png_charp profile, int proflen)); - /* Note to maintainer: profile should be png_bytep */ -#endif - -#if defined(PNG_WRITE_sPLT_SUPPORTED) -PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr, - png_sPLT_tp palette)); -#endif - -#if defined(PNG_WRITE_tRNS_SUPPORTED) -PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr, png_bytep trans, - png_color_16p values, int number, int color_type)); -#endif - -#if defined(PNG_WRITE_bKGD_SUPPORTED) -PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr, - png_color_16p values, int color_type)); -#endif - -#if defined(PNG_WRITE_hIST_SUPPORTED) -PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr, png_uint_16p hist, - int num_hist)); -#endif - -#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \ - defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED) -PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr, - png_charp key, png_charpp new_key)); -#endif - -#if defined(PNG_WRITE_tEXt_SUPPORTED) -PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_charp key, - png_charp text, png_size_t text_len)); -#endif - -#if defined(PNG_WRITE_zTXt_SUPPORTED) -PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_charp key, - png_charp text, png_size_t text_len, int compression)); -#endif - -#if defined(PNG_WRITE_iTXt_SUPPORTED) -PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr, - int compression, png_charp key, png_charp lang, png_charp lang_key, - png_charp text)); -#endif - -#if defined(PNG_TEXT_SUPPORTED) /* Added at version 1.0.14 and 1.2.4 */ -PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr, - png_infop info_ptr, png_textp text_ptr, int num_text)); -#endif - -#if defined(PNG_WRITE_oFFs_SUPPORTED) -PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr, - png_int_32 x_offset, png_int_32 y_offset, int unit_type)); -#endif - -#if defined(PNG_WRITE_pCAL_SUPPORTED) -PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose, - png_int_32 X0, png_int_32 X1, int type, int nparams, - png_charp units, png_charpp params)); -#endif - -#if defined(PNG_WRITE_pHYs_SUPPORTED) -PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr, - png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit, - int unit_type)); -#endif - -#if defined(PNG_WRITE_tIME_SUPPORTED) -PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr, - png_timep mod_time)); -#endif - -#if defined(PNG_WRITE_sCAL_SUPPORTED) -#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO) -PNG_EXTERN void png_write_sCAL PNGARG((png_structp png_ptr, - int unit, double width, double height)); +#ifdef PNG_USE_READ_MACROS +/* Inline macros to do direct reads of bytes from the input buffer. + * The png_get_int_32() routine assumes we are using two's complement + * format for negative values, which is almost certainly true. + */ +# define PNG_get_uint_32(buf) \ + (((png_uint_32)(*(buf)) << 24) + \ + ((png_uint_32)(*((buf) + 1)) << 16) + \ + ((png_uint_32)(*((buf) + 2)) << 8) + \ + ((png_uint_32)(*((buf) + 3)))) + + /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the + * function) incorrectly returned a value of type png_uint_32. + */ +# define PNG_get_uint_16(buf) \ + ((png_uint_16) \ + (((unsigned int)(*(buf)) << 8) + \ + ((unsigned int)(*((buf) + 1))))) + +# define PNG_get_int_32(buf) \ + ((png_int_32)((*(buf) & 0x80) \ + ? -((png_int_32)((png_get_uint_32(buf) ^ 0xffffffffL) + 1)) \ + : (png_int_32)png_get_uint_32(buf))) + + /* If PNG_PREFIX is defined the same thing as below happens in pnglibconf.h, + * but defining a macro name prefixed with PNG_PREFIX. + */ +# ifndef PNG_PREFIX +# define png_get_uint_32(buf) PNG_get_uint_32(buf) +# define png_get_uint_16(buf) PNG_get_uint_16(buf) +# define png_get_int_32(buf) PNG_get_int_32(buf) +# endif #else -#ifdef PNG_FIXED_POINT_SUPPORTED -PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr, - int unit, png_charp width, png_charp height)); -#endif -#endif -#endif - -/* Called when finished processing a row of data */ -PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr)); - -/* Internal use only. Called before first row of data */ -PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr)); - -#if defined(PNG_READ_GAMMA_SUPPORTED) -PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr)); +# ifdef PNG_PREFIX + /* No macros; revert to the (redefined) function */ +# define PNG_get_uint_32 (png_get_uint_32) +# define PNG_get_uint_16 (png_get_uint_16) +# define PNG_get_int_32 (png_get_int_32) +# endif #endif -/* combine a row of data, dealing with alpha, etc. if requested */ -PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row, - int mask)); - -#if defined(PNG_READ_INTERLACING_SUPPORTED) -/* expand an interlaced row */ -/* OLD pre-1.0.9 interface: -PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info, - png_bytep row, int pass, png_uint_32 transformations)); +/******************************************************************************* + * SIMPLIFIED API + ******************************************************************************* + * + * Please read the documentation in libpng-manual.txt (TODO: write said + * documentation) if you don't understand what follows. + * + * The simplified API hides the details of both libpng and the PNG file format + * itself. It allows PNG files to be read into a very limited number of + * in-memory bitmap formats or to be written from the same formats. If these + * formats do not accomodate your needs then you can, and should, use the more + * sophisticated APIs above - these support a wide variety of in-memory formats + * and a wide variety of sophisticated transformations to those formats as well + * as a wide variety of APIs to manipulate ancillary information. + * + * To read a PNG file using the simplified API: + * + * 1) Declare a 'png_image' structure (see below) on the stack and set the + * version field to PNG_IMAGE_VERSION. + * 2) Call the appropriate png_image_begin_read... function. + * 3) Set the png_image 'format' member to the required sample format. + * 4) Allocate a buffer for the image and, if required, the color-map. + * 5) Call png_image_finish_read to read the image and, if required, the + * color-map into your buffers. + * + * There are no restrictions on the format of the PNG input itself; all valid + * color types, bit depths, and interlace methods are acceptable, and the + * input image is transformed as necessary to the requested in-memory format + * during the png_image_finish_read() step. The only caveat is that if you + * request a color-mapped image from a PNG that is full-color or makes + * complex use of an alpha channel the transformation is extremely lossy and the + * result may look terrible. + * + * To write a PNG file using the simplified API: + * + * 1) Declare a 'png_image' structure on the stack and memset() it to all zero. + * 2) Initialize the members of the structure that describe the image, setting + * the 'format' member to the format of the image samples. + * 3) Call the appropriate png_image_write... function with a pointer to the + * image and, if necessary, the color-map to write the PNG data. + * + * png_image is a structure that describes the in-memory format of an image + * when it is being read or defines the in-memory format of an image that you + * need to write: */ -PNG_EXTERN void png_do_read_interlace PNGARG((png_structp png_ptr)); -#endif - -/* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */ - -#if defined(PNG_WRITE_INTERLACING_SUPPORTED) -/* grab pixels out of a row for an interlaced pass */ -PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info, - png_bytep row, int pass)); -#endif - -/* unfilter a row */ -PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr, - png_row_infop row_info, png_bytep row, png_bytep prev_row, int filter)); - -/* Choose the best filter to use and filter the row data */ -PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr, - png_row_infop row_info)); - -/* Write out the filtered row. */ -PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr, - png_bytep filtered_row)); -/* finish a row while reading, dealing with interlacing passes, etc. */ -PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr)); - -/* initialize the row buffers, etc. */ -PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr)); -/* optional call to update the users info structure */ -PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr, - png_infop info_ptr)); - -/* these are the functions that do the transformations */ -#if defined(PNG_READ_FILLER_SUPPORTED) -PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info, - png_bytep row, png_uint_32 filler, png_uint_32 flags)); -#endif - -#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) -PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info, - png_bytep row)); -#endif - -#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) -PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info, - png_bytep row)); -#endif - -#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) -PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info, - png_bytep row)); -#endif - -#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) -PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info, - png_bytep row)); -#endif - -#if defined(PNG_WRITE_FILLER_SUPPORTED) || \ - defined(PNG_READ_STRIP_ALPHA_SUPPORTED) -PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info, - png_bytep row, png_uint_32 flags)); -#endif - -#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) -PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info, png_bytep row)); -#endif - -#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED) -PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info, png_bytep row)); -#endif - -#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED) -PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr, png_row_infop - row_info, png_bytep row)); -#endif - -#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED) -PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info, - png_bytep row)); -#endif - -#if defined(PNG_READ_PACK_SUPPORTED) -PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info, png_bytep row)); -#endif - -#if defined(PNG_READ_SHIFT_SUPPORTED) -PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info, png_bytep row, - png_color_8p sig_bits)); -#endif - -#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) -PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info, png_bytep row)); -#endif - -#if defined(PNG_READ_16_TO_8_SUPPORTED) -PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info, png_bytep row)); -#endif +#define PNG_IMAGE_VERSION 1 -#if defined(PNG_READ_DITHER_SUPPORTED) -PNG_EXTERN void png_do_dither PNGARG((png_row_infop row_info, - png_bytep row, png_bytep palette_lookup, png_bytep dither_lookup)); - -# if defined(PNG_CORRECT_PALETTE_SUPPORTED) -PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr, - png_colorp palette, int num_palette)); -# endif -#endif +typedef struct png_control *png_controlp; +typedef struct +{ + png_controlp opaque; /* Initialize to NULL, free with png_image_free */ + png_uint_32 version; /* Set to PNG_IMAGE_VERSION */ + png_uint_32 width; /* Image width in pixels (columns) */ + png_uint_32 height; /* Image height in pixels (rows) */ + png_uint_32 format; /* Image format as defined below */ + png_uint_32 flags; /* A bit mask containing informational flags */ + png_uint_32 colormap_entries; + /* Number of entries in the color-map */ + + /* In the event of an error or warning the following field will be set to a + * non-zero value and the 'message' field will contain a '\0' terminated + * string with the libpng error or warning message. If both warnings and + * an error were encountered, only the error is recorded. If there + * are multiple warnings, only the first one is recorded. + * + * The upper 30 bits of this value are reserved, the low two bits contain + * a value as follows: + */ +# define PNG_IMAGE_WARNING 1 +# define PNG_IMAGE_ERROR 2 + /* + * The result is a two bit code such that a value more than 1 indicates + * a failure in the API just called: + * + * 0 - no warning or error + * 1 - warning + * 2 - error + * 3 - error preceded by warning + */ +# define PNG_IMAGE_FAILED(png_cntrl) ((((png_cntrl).warning_or_error)&0x03)>1) -#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) -PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info, png_bytep row)); -#endif + png_uint_32 warning_or_error; -#if defined(PNG_WRITE_PACK_SUPPORTED) -PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info, - png_bytep row, png_uint_32 bit_depth)); -#endif + char message[64]; +} png_image, *png_imagep; -#if defined(PNG_WRITE_SHIFT_SUPPORTED) -PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info, png_bytep row, - png_color_8p bit_depth)); -#endif +/* The samples of the image have one to four channels whose components have + * original values in the range 0 to 1.0: + * + * 1: A single gray or luminance channel (G). + * 2: A gray/luminance channel and an alpha channel (GA). + * 3: Three red, green, blue color channels (RGB). + * 4: Three color channels and an alpha channel (RGBA). + * + * The components are encoded in one of two ways: + * + * a) As a small integer, value 0..255, contained in a single byte. For the + * alpha channel the original value is simply value/255. For the color or + * luminance channels the value is encoded according to the sRGB specification + * and matches the 8-bit format expected by typical display devices. + * + * The color/gray channels are not scaled (pre-multiplied) by the alpha + * channel and are suitable for passing to color management software. + * + * b) As a value in the range 0..65535, contained in a 2-byte integer. All + * channels can be converted to the original value by dividing by 65535; all + * channels are linear. Color channels use the RGB encoding (RGB end-points) of + * the sRGB specification. This encoding is identified by the + * PNG_FORMAT_FLAG_LINEAR flag below. + * + * When the simplified API needs to convert between sRGB and linear colorspaces, + * the actual sRGB transfer curve defined in the sRGB specification (see the + * article at http://en.wikipedia.org/wiki/SRGB) is used, not the gamma=1/2.2 + * approximation used elsewhere in libpng. + * + * When an alpha channel is present it is expected to denote pixel coverage + * of the color or luminance channels and is returned as an associated alpha + * channel: the color/gray channels are scaled (pre-multiplied) by the alpha + * value. + * + * The samples are either contained directly in the image data, between 1 and 8 + * bytes per pixel according to the encoding, or are held in a color-map indexed + * by bytes in the image data. In the case of a color-map the color-map entries + * are individual samples, encoded as above, and the image data has one byte per + * pixel to select the relevant sample from the color-map. + */ -#if defined(PNG_READ_BACKGROUND_SUPPORTED) -#if defined(PNG_READ_GAMMA_SUPPORTED) -PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row, - png_color_16p trans_values, png_color_16p background, - png_color_16p background_1, - png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1, - png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1, - png_uint_16pp gamma_16_to_1, int gamma_shift)); -#else -PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row, - png_color_16p trans_values, png_color_16p background)); -#endif -#endif +/* PNG_FORMAT_* + * + * #defines to be used in png_image::format. Each #define identifies a + * particular layout of sample data and, if present, alpha values. There are + * separate defines for each of the two component encodings. + * + * A format is built up using single bit flag values. All combinations are + * valid. Formats can be built up from the flag values or you can use one of + * the predefined values below. When testing formats always use the FORMAT_FLAG + * macros to test for individual features - future versions of the library may + * add new flags. + * + * When reading or writing color-mapped images the format should be set to the + * format of the entries in the color-map then png_image_{read,write}_colormap + * called to read or write the color-map and set the format correctly for the + * image data. Do not set the PNG_FORMAT_FLAG_COLORMAP bit directly! + * + * NOTE: libpng can be built with particular features disabled, if you see + * compiler errors because the definition of one of the following flags has been + * compiled out it is because libpng does not have the required support. It is + * possible, however, for the libpng configuration to enable the format on just + * read or just write; in that case you may see an error at run time. You can + * guard against this by checking for the definition of the appropriate + * "_SUPPORTED" macro, one of: + * + * PNG_SIMPLIFIED_{READ,WRITE}_{BGR,AFIRST}_SUPPORTED + */ +#define PNG_FORMAT_FLAG_ALPHA 0x01U /* format with an alpha channel */ +#define PNG_FORMAT_FLAG_COLOR 0x02U /* color format: otherwise grayscale */ +#define PNG_FORMAT_FLAG_LINEAR 0x04U /* 2 byte channels else 1 byte */ +#define PNG_FORMAT_FLAG_COLORMAP 0x08U /* image data is color-mapped */ -#if defined(PNG_READ_GAMMA_SUPPORTED) -PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info, png_bytep row, - png_bytep gamma_table, png_uint_16pp gamma_16_table, - int gamma_shift)); +#ifdef PNG_FORMAT_BGR_SUPPORTED +# define PNG_FORMAT_FLAG_BGR 0x10U /* BGR colors, else order is RGB */ #endif -#if defined(PNG_READ_EXPAND_SUPPORTED) -PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info, - png_bytep row, png_colorp palette, png_bytep trans, int num_trans)); -PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info, - png_bytep row, png_color_16p trans_value)); +#ifdef PNG_FORMAT_AFIRST_SUPPORTED +# define PNG_FORMAT_FLAG_AFIRST 0x20U /* alpha channel comes first */ #endif -/* The following decodes the appropriate chunks, and does error correction, - * then calls the appropriate callback for the chunk if it is valid. +/* Commonly used formats have predefined macros. + * + * First the single byte (sRGB) formats: */ +#define PNG_FORMAT_GRAY 0 +#define PNG_FORMAT_GA PNG_FORMAT_FLAG_ALPHA +#define PNG_FORMAT_AG (PNG_FORMAT_GA|PNG_FORMAT_FLAG_AFIRST) +#define PNG_FORMAT_RGB PNG_FORMAT_FLAG_COLOR +#define PNG_FORMAT_BGR (PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_BGR) +#define PNG_FORMAT_RGBA (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_ALPHA) +#define PNG_FORMAT_ARGB (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_AFIRST) +#define PNG_FORMAT_BGRA (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_ALPHA) +#define PNG_FORMAT_ABGR (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_AFIRST) + +/* Then the linear 2-byte formats. When naming these "Y" is used to + * indicate a luminance (gray) channel. + */ +#define PNG_FORMAT_LINEAR_Y PNG_FORMAT_FLAG_LINEAR +#define PNG_FORMAT_LINEAR_Y_ALPHA (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_ALPHA) +#define PNG_FORMAT_LINEAR_RGB (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR) +#define PNG_FORMAT_LINEAR_RGB_ALPHA \ + (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA) + +/* With color-mapped formats the image data is one byte for each pixel, the byte + * is an index into the color-map which is formatted as above. To obtain a + * color-mapped format it is sufficient just to add the PNG_FOMAT_FLAG_COLORMAP + * to one of the above definitions, or you can use one of the definitions below. + */ +#define PNG_FORMAT_RGB_COLORMAP (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_COLORMAP) +#define PNG_FORMAT_BGR_COLORMAP (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_COLORMAP) +#define PNG_FORMAT_RGBA_COLORMAP (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_COLORMAP) +#define PNG_FORMAT_ARGB_COLORMAP (PNG_FORMAT_ARGB|PNG_FORMAT_FLAG_COLORMAP) +#define PNG_FORMAT_BGRA_COLORMAP (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_COLORMAP) +#define PNG_FORMAT_ABGR_COLORMAP (PNG_FORMAT_ABGR|PNG_FORMAT_FLAG_COLORMAP) + +/* PNG_IMAGE macros + * + * These are convenience macros to derive information from a png_image + * structure. The PNG_IMAGE_SAMPLE_ macros return values appropriate to the + * actual image sample values - either the entries in the color-map or the + * pixels in the image. The PNG_IMAGE_PIXEL_ macros return corresponding values + * for the pixels and will always return 1 for color-mapped formats. The + * remaining macros return information about the rows in the image and the + * complete image. + * + * NOTE: All the macros that take a png_image::format parameter are compile time + * constants if the format parameter is, itself, a constant. Therefore these + * macros can be used in array declarations and case labels where required. + * Similarly the macros are also pre-processor constants (sizeof is not used) so + * they can be used in #if tests. + * + * First the information about the samples. + */ +#define PNG_IMAGE_SAMPLE_CHANNELS(fmt)\ + (((fmt)&(PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA))+1) + /* Return the total number of channels in a given format: 1..4 */ + +#define PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt)\ + ((((fmt) & PNG_FORMAT_FLAG_LINEAR) >> 2)+1) + /* Return the size in bytes of a single component of a pixel or color-map + * entry (as appropriate) in the image: 1 or 2. + */ -/* decode the IHDR chunk */ -PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); - -#if defined(PNG_READ_bKGD_SUPPORTED) -PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif +#define PNG_IMAGE_SAMPLE_SIZE(fmt)\ + (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt)) + /* This is the size of the sample data for one sample. If the image is + * color-mapped it is the size of one color-map entry (and image pixels are + * one byte in size), otherwise it is the size of one image pixel. + */ -#if defined(PNG_READ_cHRM_SUPPORTED) -PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif +#define PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(fmt)\ + (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * 256) + /* The maximum size of the color-map required by the format expressed in a + * count of components. This can be used to compile-time allocate a + * color-map: + * + * png_uint_16 colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(linear_fmt)]; + * + * png_byte colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(sRGB_fmt)]; + * + * Alternatively use the PNG_IMAGE_COLORMAP_SIZE macro below to use the + * information from one of the png_image_begin_read_ APIs and dynamically + * allocate the required memory. + */ -#if defined(PNG_READ_gAMA_SUPPORTED) -PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif +/* Corresponding information about the pixels */ +#define PNG_IMAGE_PIXEL_(test,fmt)\ + (((fmt)&PNG_FORMAT_FLAG_COLORMAP)?1:test(fmt)) -#if defined(PNG_READ_hIST_SUPPORTED) -PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif +#define PNG_IMAGE_PIXEL_CHANNELS(fmt)\ + PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_CHANNELS,fmt) + /* The number of separate channels (components) in a pixel; 1 for a + * color-mapped image. + */ -#if defined(PNG_READ_iCCP_SUPPORTED) -extern void png_handle_iCCP PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif /* PNG_READ_iCCP_SUPPORTED */ +#define PNG_IMAGE_PIXEL_COMPONENT_SIZE(fmt)\ + PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_COMPONENT_SIZE,fmt) + /* The size, in bytes, of each component in a pixel; 1 for a color-mapped + * image. + */ -#if defined(PNG_READ_iTXt_SUPPORTED) -PNG_EXTERN void png_handle_iTXt PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif +#define PNG_IMAGE_PIXEL_SIZE(fmt) PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_SIZE,fmt) + /* The size, in bytes, of a complete pixel; 1 for a color-mapped image. */ -#if defined(PNG_READ_oFFs_SUPPORTED) -PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif +/* Information about the whole row, or whole image */ +#define PNG_IMAGE_ROW_STRIDE(image)\ + (PNG_IMAGE_PIXEL_CHANNELS((image).format) * (image).width) + /* Return the total number of components in a single row of the image; this + * is the minimum 'row stride', the minimum count of components between each + * row. For a color-mapped image this is the minimum number of bytes in a + * row. + */ -#if defined(PNG_READ_pCAL_SUPPORTED) -PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif +#define PNG_IMAGE_BUFFER_SIZE(image, row_stride)\ + (PNG_IMAGE_PIXEL_COMPONENT_SIZE((image).format)*(image).height*(row_stride)) + /* Return the size, in bytes, of an image buffer given a png_image and a row + * stride - the number of components to leave space for in each row. + */ -#if defined(PNG_READ_pHYs_SUPPORTED) -PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif +#define PNG_IMAGE_SIZE(image)\ + PNG_IMAGE_BUFFER_SIZE(image, PNG_IMAGE_ROW_STRIDE(image)) + /* Return the size, in bytes, of the image in memory given just a png_image; + * the row stride is the minimum stride required for the image. + */ -#if defined(PNG_READ_sBIT_SUPPORTED) -PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif +#define PNG_IMAGE_COLORMAP_SIZE(image)\ + (PNG_IMAGE_SAMPLE_SIZE((image).format) * (image).colormap_entries) + /* Return the size, in bytes, of the color-map of this image. If the image + * format is not a color-map format this will return a size sufficient for + * 256 entries in the given format; check PNG_FORMAT_FLAG_COLORMAP if + * you don't want to allocate a color-map in this case. + */ -#if defined(PNG_READ_sCAL_SUPPORTED) -PNG_EXTERN void png_handle_sCAL PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif +/* PNG_IMAGE_FLAG_* + * + * Flags containing additional information about the image are held in the + * 'flags' field of png_image. + */ +#define PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB 0x01 + /* This indicates the the RGB values of the in-memory bitmap do not + * correspond to the red, green and blue end-points defined by sRGB. + */ -#if defined(PNG_READ_sPLT_SUPPORTED) -extern void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif /* PNG_READ_sPLT_SUPPORTED */ +#define PNG_IMAGE_FLAG_FAST 0x02 + /* On write emphasise speed over compression; the resultant PNG file will be + * larger but will be produced significantly faster, particular for large + * images. Do not use this option for images which will be distributed, only + * used it when producing intermediate files that will be read back in + * repeatedly. For a typical 24-bit image the option will double the read + * speed at the cost of increasing the image size by 25%, however for many + * more compressible images the PNG file can be 10 times larger with only a + * slight speed gain. + */ -#if defined(PNG_READ_sRGB_SUPPORTED) -PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif +#define PNG_IMAGE_FLAG_16BIT_sRGB 0x04 + /* On read if the image is a 16-bit per component image and there is no gAMA + * or sRGB chunk assume that the components are sRGB encoded. Notice that + * images output by the simplified API always have gamma information; setting + * this flag only affects the interpretation of 16-bit images from an + * external source. It is recommended that the application expose this flag + * to the user; the user can normally easily recognize the difference between + * linear and sRGB encoding. This flag has no effect on write - the data + * passed to the write APIs must have the correct encoding (as defined + * above.) + * + * If the flag is not set (the default) input 16-bit per component data is + * assumed to be linear. + * + * NOTE: the flag can only be set after the png_image_begin_read_ call, + * because that call initializes the 'flags' field. + */ -#if defined(PNG_READ_tEXt_SUPPORTED) -PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif +#ifdef PNG_SIMPLIFIED_READ_SUPPORTED +/* READ APIs + * --------- + * + * The png_image passed to the read APIs must have been initialized by setting + * the png_controlp field 'opaque' to NULL (or, safer, memset the whole thing.) + */ +#ifdef PNG_STDIO_SUPPORTED +PNG_EXPORT(234, int, png_image_begin_read_from_file, (png_imagep image, + const char *file_name)); + /* The named file is opened for read and the image header is filled in + * from the PNG header in the file. + */ -#if defined(PNG_READ_tIME_SUPPORTED) -PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif +PNG_EXPORT(235, int, png_image_begin_read_from_stdio, (png_imagep image, + FILE* file)); + /* The PNG header is read from the stdio FILE object. */ +#endif /* PNG_STDIO_SUPPORTED */ + +PNG_EXPORT(236, int, png_image_begin_read_from_memory, (png_imagep image, + png_const_voidp memory, png_size_t size)); + /* The PNG header is read from the given memory buffer. */ + +PNG_EXPORT(237, int, png_image_finish_read, (png_imagep image, + png_const_colorp background, void *buffer, png_int_32 row_stride, + void *colormap)); + /* Finish reading the image into the supplied buffer and clean up the + * png_image structure. + * + * row_stride is the step, in byte or 2-byte units as appropriate, + * between adjacent rows. A positive stride indicates that the top-most row + * is first in the buffer - the normal top-down arrangement. A negative + * stride indicates that the bottom-most row is first in the buffer. + * + * background need only be supplied if an alpha channel must be removed from + * a png_byte format and the removal is to be done by compositing on a solid + * color; otherwise it may be NULL and any composition will be done directly + * onto the buffer. The value is an sRGB color to use for the background, + * for grayscale output the green channel is used. + * + * background must be supplied when an alpha channel must be removed from a + * single byte color-mapped output format, in other words if: + * + * 1) The original format from png_image_begin_read_from_* had + * PNG_FORMAT_FLAG_ALPHA set. + * 2) The format set by the application does not. + * 3) The format set by the application has PNG_FORMAT_FLAG_COLORMAP set and + * PNG_FORMAT_FLAG_LINEAR *not* set. + * + * For linear output removing the alpha channel is always done by compositing + * on black and background is ignored. + * + * colormap must be supplied when PNG_FORMAT_FLAG_COLORMAP is set. It must + * be at least the size (in bytes) returned by PNG_IMAGE_COLORMAP_SIZE. + * image->colormap_entries will be updated to the actual number of entries + * written to the colormap; this may be less than the original value. + */ -#if defined(PNG_READ_tRNS_SUPPORTED) -PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); -#endif +PNG_EXPORT(238, void, png_image_free, (png_imagep image)); + /* Free any data allocated by libpng in image->opaque, setting the pointer to + * NULL. May be called at any time after the structure is initialized. + */ +#endif /* PNG_SIMPLIFIED_READ_SUPPORTED */ + +#ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED +/* WRITE APIS + * ---------- + * For write you must initialize a png_image structure to describe the image to + * be written. To do this use memset to set the whole structure to 0 then + * initialize fields describing your image. + * + * version: must be set to PNG_IMAGE_VERSION + * opaque: must be initialized to NULL + * width: image width in pixels + * height: image height in rows + * format: the format of the data (image and color-map) you wish to write + * flags: set to 0 unless one of the defined flags applies; set + * PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB for color format images where the RGB + * values do not correspond to the colors in sRGB. + * colormap_entries: set to the number of entries in the color-map (0 to 256) + */ +PNG_EXPORT(239, int, png_image_write_to_file, (png_imagep image, + const char *file, int convert_to_8bit, const void *buffer, + png_int_32 row_stride, const void *colormap)); + /* Write the image to the named file. */ + +PNG_EXPORT(240, int, png_image_write_to_stdio, (png_imagep image, FILE *file, + int convert_to_8_bit, const void *buffer, png_int_32 row_stride, + const void *colormap)); + /* Write the image to the given (FILE*). */ + +/* With both write APIs if image is in one of the linear formats with 16-bit + * data then setting convert_to_8_bit will cause the output to be an 8-bit PNG + * gamma encoded according to the sRGB specification, otherwise a 16-bit linear + * encoded PNG file is written. + * + * With color-mapped data formats the colormap parameter point to a color-map + * with at least image->colormap_entries encoded in the specified format. If + * the format is linear the written PNG color-map will be converted to sRGB + * regardless of the convert_to_8_bit flag. + * + * With all APIs row_stride is handled as in the read APIs - it is the spacing + * from one row to the next in component sized units (1 or 2 bytes) and if + * negative indicates a bottom-up row layout in the buffer. + * + * Note that the write API does not support interlacing or sub-8-bit pixels. + */ +#endif /* PNG_SIMPLIFIED_WRITE_SUPPORTED */ +/******************************************************************************* + * END OF SIMPLIFIED API + ******************************************************************************/ + +#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED +PNG_EXPORT(242, void, png_set_check_for_invalid_index, + (png_structrp png_ptr, int allowed)); +# ifdef PNG_GET_PALETTE_MAX_SUPPORTED +PNG_EXPORT(243, int, png_get_palette_max, (png_const_structp png_ptr, + png_const_infop info_ptr)); +# endif +#endif /* CHECK_FOR_INVALID_INDEX */ -#if defined(PNG_READ_zTXt_SUPPORTED) -PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr, - png_uint_32 length)); +/******************************************************************************* + * IMPLEMENTATION OPTIONS + ******************************************************************************* + * + * Support for arbitrary implementation-specific optimizations. The API allows + * particular options to be turned on or off. 'Option' is the number of the + * option and 'onoff' is 0 (off) or non-0 (on). The value returned is given + * by the PNG_OPTION_ defines below. + * + * HARDWARE: normally hardware capabilites, such as the Intel SSE instructions, + * are detected at run time, however sometimes it may be impossible + * to do this in user mode, in which case it is necessary to discover + * the capabilities in an OS specific way. Such capabilities are + * listed here when libpng has support for them and must be turned + * ON by the application if present. + * + * SOFTWARE: sometimes software optimizations actually result in performance + * decrease on some architectures or systems, or with some sets of + * PNG images. 'Software' options allow such optimizations to be + * selected at run time. + */ +#ifdef PNG_SET_OPTION_SUPPORTED +#ifdef PNG_ARM_NEON_API_SUPPORTED +# define PNG_ARM_NEON 0 /* HARDWARE: ARM Neon SIMD instructions supported */ #endif +#define PNG_OPTION_NEXT 2 /* Next option - numbers must be even */ -PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr, - png_infop info_ptr, png_uint_32 length)); - -PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr, - png_bytep chunk_name)); - -/* handle the transformations for reading and writing */ -PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr)); -PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr)); +/* Return values: NOTE: there are four values and 'off' is *not* zero */ +#define PNG_OPTION_UNSET 0 /* Unset - defaults to off */ +#define PNG_OPTION_INVALID 1 /* Option number out of range */ +#define PNG_OPTION_OFF 2 +#define PNG_OPTION_ON 3 -PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr)); - -#ifdef PNG_PROGRESSIVE_READ_SUPPORTED -PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr, - png_infop info_ptr)); -PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr, - png_infop info_ptr)); -PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr)); -PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr, - png_uint_32 length)); -PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr)); -PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr)); -PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr, - png_bytep buffer, png_size_t buffer_length)); -PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr)); -PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr, - png_bytep buffer, png_size_t buffer_length)); -PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr)); -PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr, - png_infop info_ptr, png_uint_32 length)); -PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr, - png_infop info_ptr)); -PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr, - png_infop info_ptr)); -PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row)); -PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr, - png_infop info_ptr)); -PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr, - png_infop info_ptr)); -PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr)); -#if defined(PNG_READ_tEXt_SUPPORTED) -PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr, - png_infop info_ptr, png_uint_32 length)); -PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr, - png_infop info_ptr)); -#endif -#if defined(PNG_READ_zTXt_SUPPORTED) -PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr, - png_infop info_ptr, png_uint_32 length)); -PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr, - png_infop info_ptr)); -#endif -#if defined(PNG_READ_iTXt_SUPPORTED) -PNG_EXTERN void png_push_handle_iTXt PNGARG((png_structp png_ptr, - png_infop info_ptr, png_uint_32 length)); -PNG_EXTERN void png_push_read_iTXt PNGARG((png_structp png_ptr, - png_infop info_ptr)); +PNG_EXPORT(244, int, png_set_option, (png_structrp png_ptr, int option, + int onoff)); #endif -#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ +/******************************************************************************* + * END OF HARDWARE OPTIONS + ******************************************************************************/ -#ifdef PNG_MNG_FEATURES_SUPPORTED -PNG_EXTERN void png_do_read_intrapixel PNGARG((png_row_infop row_info, - png_bytep row)); -PNG_EXTERN void png_do_write_intrapixel PNGARG((png_row_infop row_info, - png_bytep row)); -#endif +/* Maintainer: Put new public prototypes here ^, in libpng.3, and project + * defs, scripts/pnglibconf.h, and scripts/pnglibconf.h.prebuilt + */ -#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) -/* png.c */ /* PRIVATE */ -PNG_EXTERN void png_init_mmx_flags PNGARG((png_structp png_ptr)); +/* The last ordinal number (this is the *last* one already used; the next + * one to use is one more than this.) Maintainer, remember to add an entry to + * scripts/symbols.def as well. + */ +#ifdef PNG_EXPORT_LAST_ORDINAL + PNG_EXPORT_LAST_ORDINAL(244); #endif -/* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */ - -#endif /* PNG_INTERNAL */ #ifdef __cplusplus } #endif #endif /* PNG_VERSION_INFO_ONLY */ -/* do not put anything past this line */ +/* Do not put anything past this line */ #endif /* PNG_H */