358 lines
15 KiB
C
358 lines
15 KiB
C
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/* pngstruct.h - header file for PNG reference library
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*
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* Copyright (c) 1998-2011 Glenn Randers-Pehrson
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* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
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* (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
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*
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* Last changed in libpng 1.5.9 [March 29, 2012]
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*
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* This code is released under the libpng license.
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* For conditions of distribution and use, see the disclaimer
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* and license in png.h
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*/
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/* The structure that holds the information to read and write PNG files.
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* The only people who need to care about what is inside of this are the
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* people who will be modifying the library for their own special needs.
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* It should NOT be accessed directly by an application.
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*/
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#ifndef PNGSTRUCT_H
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#define PNGSTRUCT_H
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/* zlib.h defines the structure z_stream, an instance of which is included
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* in this structure and is required for decompressing the LZ compressed
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* data in PNG files.
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*/
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#include "zlib.h"
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struct png_struct_def
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{
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#ifdef PNG_SETJMP_SUPPORTED
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jmp_buf longjmp_buffer; /* used in png_error */
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png_longjmp_ptr longjmp_fn;/* setjmp non-local goto function. */
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#endif
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png_error_ptr error_fn; /* function for printing errors and aborting */
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#ifdef PNG_WARNINGS_SUPPORTED
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png_error_ptr warning_fn; /* function for printing warnings */
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#endif
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png_voidp error_ptr; /* user supplied struct for error functions */
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png_rw_ptr write_data_fn; /* function for writing output data */
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png_rw_ptr read_data_fn; /* function for reading input data */
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png_voidp io_ptr; /* ptr to application struct for I/O functions */
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#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
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png_user_transform_ptr read_user_transform_fn; /* user read transform */
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#endif
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#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
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png_user_transform_ptr write_user_transform_fn; /* user write transform */
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#endif
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/* These were added in libpng-1.0.2 */
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#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
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#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
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defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
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png_voidp user_transform_ptr; /* user supplied struct for user transform */
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png_byte user_transform_depth; /* bit depth of user transformed pixels */
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png_byte user_transform_channels; /* channels in user transformed pixels */
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#endif
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#endif
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png_uint_32 mode; /* tells us where we are in the PNG file */
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png_uint_32 flags; /* flags indicating various things to libpng */
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png_uint_32 transformations; /* which transformations to perform */
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z_stream zstream; /* pointer to decompression structure (below) */
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png_bytep zbuf; /* buffer for zlib */
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uInt zbuf_size; /* size of zbuf (typically 65536) */
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#ifdef PNG_WRITE_SUPPORTED
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/* Added in 1.5.4: state to keep track of whether the zstream has been
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* initialized and if so whether it is for IDAT or some other chunk.
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*/
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#define PNG_ZLIB_UNINITIALIZED 0
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#define PNG_ZLIB_FOR_IDAT 1
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#define PNG_ZLIB_FOR_TEXT 2 /* anything other than IDAT */
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#define PNG_ZLIB_USE_MASK 3 /* bottom two bits */
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#define PNG_ZLIB_IN_USE 4 /* a flag value */
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png_uint_32 zlib_state; /* State of zlib initialization */
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/* End of material added at libpng 1.5.4 */
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int zlib_level; /* holds zlib compression level */
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int zlib_method; /* holds zlib compression method */
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int zlib_window_bits; /* holds zlib compression window bits */
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int zlib_mem_level; /* holds zlib compression memory level */
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int zlib_strategy; /* holds zlib compression strategy */
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#endif
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/* Added at libpng 1.5.4 */
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#if defined(PNG_WRITE_COMPRESSED_TEXT_SUPPORTED) || \
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defined(PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED)
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int zlib_text_level; /* holds zlib compression level */
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int zlib_text_method; /* holds zlib compression method */
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int zlib_text_window_bits; /* holds zlib compression window bits */
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int zlib_text_mem_level; /* holds zlib compression memory level */
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int zlib_text_strategy; /* holds zlib compression strategy */
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#endif
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/* End of material added at libpng 1.5.4 */
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png_uint_32 width; /* width of image in pixels */
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png_uint_32 height; /* height of image in pixels */
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png_uint_32 num_rows; /* number of rows in current pass */
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png_uint_32 usr_width; /* width of row at start of write */
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png_size_t rowbytes; /* size of row in bytes */
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png_uint_32 iwidth; /* width of current interlaced row in pixels */
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png_uint_32 row_number; /* current row in interlace pass */
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png_uint_32 chunk_name; /* PNG_CHUNK() id of current chunk */
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png_bytep prev_row; /* buffer to save previous (unfiltered) row.
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* This is a pointer into big_prev_row
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*/
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png_bytep row_buf; /* buffer to save current (unfiltered) row.
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* This is a pointer into big_row_buf
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*/
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png_bytep sub_row; /* buffer to save "sub" row when filtering */
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png_bytep up_row; /* buffer to save "up" row when filtering */
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png_bytep avg_row; /* buffer to save "avg" row when filtering */
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png_bytep paeth_row; /* buffer to save "Paeth" row when filtering */
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png_size_t info_rowbytes; /* Added in 1.5.4: cache of updated row bytes */
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png_uint_32 idat_size; /* current IDAT size for read */
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png_uint_32 crc; /* current chunk CRC value */
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png_colorp palette; /* palette from the input file */
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png_uint_16 num_palette; /* number of color entries in palette */
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/* Added at libpng-1.5.10 */
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#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
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int num_palette_max; /* maximum palette index found in IDAT */
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#endif
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png_uint_16 num_trans; /* number of transparency values */
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png_byte compression; /* file compression type (always 0) */
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png_byte filter; /* file filter type (always 0) */
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png_byte interlaced; /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
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png_byte pass; /* current interlace pass (0 - 6) */
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png_byte do_filter; /* row filter flags (see PNG_FILTER_ below ) */
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png_byte color_type; /* color type of file */
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png_byte bit_depth; /* bit depth of file */
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png_byte usr_bit_depth; /* bit depth of users row: write only */
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png_byte pixel_depth; /* number of bits per pixel */
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png_byte channels; /* number of channels in file */
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png_byte usr_channels; /* channels at start of write: write only */
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png_byte sig_bytes; /* magic bytes read/written from start of file */
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png_byte maximum_pixel_depth;
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/* pixel depth used for the row buffers */
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png_byte transformed_pixel_depth;
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/* pixel depth after read/write transforms */
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png_byte io_chunk_string[5];
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/* string name of chunk */
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#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
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png_uint_16 filler; /* filler bytes for pixel expansion */
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#endif
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#if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
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defined(PNG_READ_ALPHA_MODE_SUPPORTED)
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png_byte background_gamma_type;
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png_fixed_point background_gamma;
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png_color_16 background; /* background color in screen gamma space */
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#ifdef PNG_READ_GAMMA_SUPPORTED
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png_color_16 background_1; /* background normalized to gamma 1.0 */
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#endif
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#endif /* PNG_bKGD_SUPPORTED */
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#ifdef PNG_WRITE_FLUSH_SUPPORTED
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png_flush_ptr output_flush_fn; /* Function for flushing output */
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png_uint_32 flush_dist; /* how many rows apart to flush, 0 - no flush */
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png_uint_32 flush_rows; /* number of rows written since last flush */
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#endif
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#ifdef PNG_READ_GAMMA_SUPPORTED
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int gamma_shift; /* number of "insignificant" bits in 16-bit gamma */
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png_fixed_point gamma; /* file gamma value */
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png_fixed_point screen_gamma; /* screen gamma value (display_exponent) */
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png_bytep gamma_table; /* gamma table for 8-bit depth files */
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png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
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#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
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defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
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defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
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png_bytep gamma_from_1; /* converts from 1.0 to screen */
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png_bytep gamma_to_1; /* converts from file to 1.0 */
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png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
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png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
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#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
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#endif
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#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)
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png_color_8 sig_bit; /* significant bits in each available channel */
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#endif
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#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
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png_color_8 shift; /* shift for significant bit tranformation */
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#endif
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#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
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|| defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
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png_bytep trans_alpha; /* alpha values for paletted files */
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png_color_16 trans_color; /* transparent color for non-paletted files */
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#endif
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png_read_status_ptr read_row_fn; /* called after each row is decoded */
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png_write_status_ptr write_row_fn; /* called after each row is encoded */
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#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
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png_progressive_info_ptr info_fn; /* called after header data fully read */
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png_progressive_row_ptr row_fn; /* called after a prog. row is decoded */
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png_progressive_end_ptr end_fn; /* called after image is complete */
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png_bytep save_buffer_ptr; /* current location in save_buffer */
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png_bytep save_buffer; /* buffer for previously read data */
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png_bytep current_buffer_ptr; /* current location in current_buffer */
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png_bytep current_buffer; /* buffer for recently used data */
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png_uint_32 push_length; /* size of current input chunk */
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png_uint_32 skip_length; /* bytes to skip in input data */
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png_size_t save_buffer_size; /* amount of data now in save_buffer */
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png_size_t save_buffer_max; /* total size of save_buffer */
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png_size_t buffer_size; /* total amount of available input data */
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png_size_t current_buffer_size; /* amount of data now in current_buffer */
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int process_mode; /* what push library is currently doing */
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int cur_palette; /* current push library palette index */
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#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
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#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
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/* For the Borland special 64K segment handler */
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png_bytepp offset_table_ptr;
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png_bytep offset_table;
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png_uint_16 offset_table_number;
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png_uint_16 offset_table_count;
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png_uint_16 offset_table_count_free;
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#endif
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#ifdef PNG_READ_QUANTIZE_SUPPORTED
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png_bytep palette_lookup; /* lookup table for quantizing */
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png_bytep quantize_index; /* index translation for palette files */
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#endif
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#if defined(PNG_READ_QUANTIZE_SUPPORTED) || defined(PNG_hIST_SUPPORTED)
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png_uint_16p hist; /* histogram */
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#endif
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#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
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png_byte heuristic_method; /* heuristic for row filter selection */
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png_byte num_prev_filters; /* number of weights for previous rows */
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png_bytep prev_filters; /* filter type(s) of previous row(s) */
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png_uint_16p filter_weights; /* weight(s) for previous line(s) */
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png_uint_16p inv_filter_weights; /* 1/weight(s) for previous line(s) */
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png_uint_16p filter_costs; /* relative filter calculation cost */
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png_uint_16p inv_filter_costs; /* 1/relative filter calculation cost */
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#endif
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#ifdef PNG_TIME_RFC1123_SUPPORTED
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char time_buffer[29]; /* String to hold RFC 1123 time text */
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#endif
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/* New members added in libpng-1.0.6 */
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png_uint_32 free_me; /* flags items libpng is responsible for freeing */
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#ifdef PNG_USER_CHUNKS_SUPPORTED
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png_voidp user_chunk_ptr;
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png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */
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#endif
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#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
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int num_chunk_list;
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png_bytep chunk_list;
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#endif
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#ifdef PNG_READ_sRGB_SUPPORTED
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/* Added in 1.5.5 to record an sRGB chunk in the png. */
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png_byte is_sRGB;
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#endif
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/* New members added in libpng-1.0.3 */
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#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
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png_byte rgb_to_gray_status;
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/* Added in libpng 1.5.5 to record setting of coefficients: */
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png_byte rgb_to_gray_coefficients_set;
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/* These were changed from png_byte in libpng-1.0.6 */
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png_uint_16 rgb_to_gray_red_coeff;
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png_uint_16 rgb_to_gray_green_coeff;
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/* deleted in 1.5.5: rgb_to_gray_blue_coeff; */
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#endif
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/* New member added in libpng-1.0.4 (renamed in 1.0.9) */
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#if defined(PNG_MNG_FEATURES_SUPPORTED)
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/* Changed from png_byte to png_uint_32 at version 1.2.0 */
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png_uint_32 mng_features_permitted;
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#endif
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/* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */
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#ifdef PNG_MNG_FEATURES_SUPPORTED
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png_byte filter_type;
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#endif
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/* New members added in libpng-1.2.0 */
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/* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
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#ifdef PNG_USER_MEM_SUPPORTED
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png_voidp mem_ptr; /* user supplied struct for mem functions */
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png_malloc_ptr malloc_fn; /* function for allocating memory */
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png_free_ptr free_fn; /* function for freeing memory */
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#endif
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/* New member added in libpng-1.0.13 and 1.2.0 */
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png_bytep big_row_buf; /* buffer to save current (unfiltered) row */
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#ifdef PNG_READ_QUANTIZE_SUPPORTED
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/* The following three members were added at version 1.0.14 and 1.2.4 */
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png_bytep quantize_sort; /* working sort array */
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png_bytep index_to_palette; /* where the original index currently is
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in the palette */
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png_bytep palette_to_index; /* which original index points to this
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palette color */
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#endif
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/* New members added in libpng-1.0.16 and 1.2.6 */
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png_byte compression_type;
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|
|
||
|
|
#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 member added in libpng-1.2.26 */
|
||
|
|
png_size_t old_big_row_buf_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
|
||
|
|
|
||
|
|
/* New member added in libpng-1.5.6 */
|
||
|
|
png_bytep big_prev_row;
|
||
|
|
|
||
|
|
void (*read_filter[PNG_FILTER_VALUE_LAST-1])(png_row_infop row_info,
|
||
|
|
png_bytep row, png_const_bytep prev_row);
|
||
|
|
};
|
||
|
|
#endif /* PNGSTRUCT_H */
|