/* pngstruct.h - header file for PNG reference library * * Copyright (c) 1998-2011 Glenn Randers-Pehrson * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) * * Last changed in libpng 1.5.0 [January 6, 2011] * * This code is released under the libpng license. * For conditions of distribution and use, see the disclaimer * and license in png.h */ /* The structure that holds the information to read and write PNG files. * The only people who need to care about what is inside of this are the * people who will be modifying the library for their own special needs. * It should NOT be accessed directly by an application. */ #ifndef PNGSTRUCT_H #define PNGSTRUCT_H /* zlib.h defines the structure z_stream, an instance of which is included * in this structure and is required for decompressing the LZ compressed * data in PNG files. */ #include "zlib.h" struct png_struct_def { #ifdef PNG_SETJMP_SUPPORTED jmp_buf png_jmpbuf; /* used in png_error */ png_longjmp_ptr longjmp_fn;/* setjmp non-local goto function. */ #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 */ #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED png_user_transform_ptr read_user_transform_fn; /* user read transform */ #endif #ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED png_user_transform_ptr write_user_transform_fn; /* user write transform */ #endif /* These were added in libpng-1.0.2 */ #ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) png_voidp user_transform_ptr; /* user supplied struct for user transform */ png_byte user_transform_depth; /* bit depth of user transformed pixels */ png_byte user_transform_channels; /* channels in user transformed pixels */ #endif #endif png_uint_32 mode; /* tells us where we are in the PNG file */ png_uint_32 flags; /* flags indicating various things to libpng */ png_uint_32 transformations; /* which transformations to perform */ z_stream zstream; /* pointer to decompression structure (below) */ png_bytep zbuf; /* buffer for zlib */ uInt zbuf_size; /* size of zbuf (typically 65536) */ 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_size_t rowbytes; /* size of row in bytes */ png_uint_32 iwidth; /* width of current interlaced row in pixels */ png_uint_32 row_number; /* current row in interlace pass */ png_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) png_uint_16 filler; /* filler bytes for pixel expansion */ #endif #ifdef PNG_bKGD_SUPPORTED png_byte background_gamma_type; png_fixed_point background_gamma; png_color_16 background; /* background color in screen gamma space */ #ifdef PNG_READ_GAMMA_SUPPORTED png_color_16 background_1; /* background normalized to gamma 1.0 */ #endif #endif /* PNG_bKGD_SUPPORTED */ #ifdef PNG_WRITE_FLUSH_SUPPORTED png_flush_ptr output_flush_fn; /* Function for flushing output */ png_uint_32 flush_dist; /* how many rows apart to flush, 0 - no flush */ png_uint_32 flush_rows; /* number of rows written since last flush */ #endif #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) int gamma_shift; /* number of "insignificant" bits in 16-bit gamma */ png_fixed_point gamma; /* file gamma value */ png_fixed_point screen_gamma; /* screen gamma value (display_exponent) */ #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_alpha; /* alpha values for paletted files */ png_color_16 trans_color; /* transparent color for non-paletted files */ #endif png_read_status_ptr read_row_fn; /* called after each row is decoded */ png_write_status_ptr write_row_fn; /* called after each row is encoded */ #ifdef PNG_PROGRESSIVE_READ_SUPPORTED png_progressive_info_ptr info_fn; /* called after header data fully read */ png_progressive_row_ptr row_fn; /* called after a prog. row is decoded */ png_progressive_end_ptr end_fn; /* called after image is complete */ png_bytep save_buffer_ptr; /* current location in save_buffer */ png_bytep save_buffer; /* buffer for previously read data */ png_bytep current_buffer_ptr; /* current location in current_buffer */ png_bytep current_buffer; /* buffer for recently used data */ png_uint_32 push_length; /* size of current input chunk */ png_uint_32 skip_length; /* bytes to skip in input data */ png_size_t save_buffer_size; /* amount of data now in save_buffer */ png_size_t save_buffer_max; /* total size of save_buffer */ png_size_t buffer_size; /* total amount of available input data */ png_size_t current_buffer_size; /* amount of data now in current_buffer */ int process_mode; /* what push library is currently doing */ int cur_palette; /* current push library palette index */ # ifdef 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 #ifdef PNG_READ_QUANTIZE_SUPPORTED png_bytep palette_lookup; /* lookup table for quantizing */ png_bytep quantize_index; /* index translation for palette files */ #endif #if defined(PNG_READ_QUANTIZE_SUPPORTED) || defined(PNG_hIST_SUPPORTED) png_uint_16p hist; /* histogram */ #endif #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED png_byte heuristic_method; /* heuristic for row filter selection */ png_byte num_prev_filters; /* number of weights for previous rows */ png_bytep prev_filters; /* filter type(s) of previous row(s) */ png_uint_16p filter_weights; /* weight(s) for previous line(s) */ png_uint_16p inv_filter_weights; /* 1/weight(s) for previous line(s) */ png_uint_16p filter_costs; /* relative filter calculation cost */ png_uint_16p inv_filter_costs; /* 1/relative filter calculation cost */ #endif #ifdef PNG_TIME_RFC1123_SUPPORTED png_charp time_buffer; /* String to hold RFC 1123 time text */ #endif /* New members added in libpng-1.0.6 */ png_uint_32 free_me; /* flags items libpng is responsible for freeing */ #ifdef PNG_USER_CHUNKS_SUPPORTED png_voidp user_chunk_ptr; png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */ #endif #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED int num_chunk_list; png_bytep chunk_list; #endif /* New members added in libpng-1.0.3 */ #ifdef 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 */ png_uint_32 mng_features_permitted; #endif /* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */ #ifdef PNG_MNG_FEATURES_SUPPORTED png_byte filter_type; #endif /* New members added in libpng-1.2.0 */ /* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */ #ifdef PNG_USER_MEM_SUPPORTED png_voidp mem_ptr; /* user supplied struct for mem functions */ png_malloc_ptr malloc_fn; /* function for allocating memory */ png_free_ptr free_fn; /* function for freeing memory */ #endif /* New member added in libpng-1.0.13 and 1.2.0 */ png_bytep big_row_buf; /* buffer to save current (unfiltered) row */ #ifdef PNG_READ_QUANTIZE_SUPPORTED /* The following three members were added at version 1.0.14 and 1.2.4 */ png_bytep quantize_sort; /* working sort array */ png_bytep index_to_palette; /* where the original index currently is in the palette */ png_bytep palette_to_index; /* which original index points to this palette color */ #endif /* New members added in libpng-1.0.16 and 1.2.6 */ png_byte compression_type; #ifdef PNG_USER_LIMITS_SUPPORTED png_uint_32 user_width_max; png_uint_32 user_height_max; /* Added in libpng-1.4.0: Total number of sPLT, text, and unknown * chunks that can be stored (0 means unlimited). */ png_uint_32 user_chunk_cache_max; /* Total memory that a zTXt, sPLT, iTXt, iCCP, or unknown chunk * can occupy when decompressed. 0 means unlimited. */ png_alloc_size_t user_chunk_malloc_max; #endif /* New member added in libpng-1.0.25 and 1.2.17 */ #ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED /* Storage for unknown chunk that the library doesn't recognize. */ png_unknown_chunk unknown_chunk; #endif /* New members added in libpng-1.2.26 */ png_size_t old_big_row_buf_size; png_size_t old_prev_row_size; /* New member added in libpng-1.2.30 */ png_charp chunkdata; /* buffer for reading chunk data */ #ifdef PNG_IO_STATE_SUPPORTED /* New member added in libpng-1.4.0 */ png_uint_32 io_state; #endif }; #endif /* PNGSTRUCT_H */