379 lines
19 KiB
C
379 lines
19 KiB
C
/* 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, except to store
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* the jmp_buf.
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*/
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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 jmpbuf PNG_DEPSTRUCT; /* used in png_error */
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png_longjmp_ptr longjmp_fn PNG_DEPSTRUCT;/* setjmp non-local goto
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function. */
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#endif
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png_error_ptr error_fn PNG_DEPSTRUCT; /* function for printing
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errors and aborting */
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png_error_ptr warning_fn PNG_DEPSTRUCT; /* function for printing
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warnings */
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png_voidp error_ptr PNG_DEPSTRUCT; /* user supplied struct for
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error functions */
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png_rw_ptr write_data_fn PNG_DEPSTRUCT; /* function for writing
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output data */
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png_rw_ptr read_data_fn PNG_DEPSTRUCT; /* function for reading
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input data */
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png_voidp io_ptr PNG_DEPSTRUCT; /* ptr to application struct
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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 PNG_DEPSTRUCT; /* user read
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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 PNG_DEPSTRUCT; /* user write
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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 PNG_DEPSTRUCT; /* user supplied struct
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for user transform */
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png_byte user_transform_depth PNG_DEPSTRUCT; /* bit depth of user
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transformed pixels */
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png_byte user_transform_channels PNG_DEPSTRUCT; /* channels in user
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transformed pixels */
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#endif
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#endif
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png_uint_32 mode PNG_DEPSTRUCT; /* tells us where we are in
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the PNG file */
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png_uint_32 flags PNG_DEPSTRUCT; /* flags indicating various
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things to libpng */
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png_uint_32 transformations PNG_DEPSTRUCT; /* which transformations
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to perform */
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z_stream zstream PNG_DEPSTRUCT; /* pointer to decompression
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structure (below) */
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png_bytep zbuf PNG_DEPSTRUCT; /* buffer for zlib */
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png_size_t zbuf_size PNG_DEPSTRUCT; /* size of zbuf */
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int zlib_level PNG_DEPSTRUCT; /* holds zlib compression level */
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int zlib_method PNG_DEPSTRUCT; /* holds zlib compression method */
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int zlib_window_bits PNG_DEPSTRUCT; /* holds zlib compression window
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bits */
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int zlib_mem_level PNG_DEPSTRUCT; /* holds zlib compression memory
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level */
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int zlib_strategy PNG_DEPSTRUCT; /* holds zlib compression
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strategy */
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png_uint_32 width PNG_DEPSTRUCT; /* width of image in pixels */
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png_uint_32 height PNG_DEPSTRUCT; /* height of image in pixels */
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png_uint_32 num_rows PNG_DEPSTRUCT; /* number of rows in current pass */
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png_uint_32 usr_width PNG_DEPSTRUCT; /* width of row at start of write */
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png_size_t rowbytes PNG_DEPSTRUCT; /* size of row in bytes */
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png_uint_32 iwidth PNG_DEPSTRUCT; /* width of current interlaced
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row in pixels */
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png_uint_32 row_number PNG_DEPSTRUCT; /* current row in interlace pass */
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png_bytep prev_row PNG_DEPSTRUCT; /* buffer to save previous
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(unfiltered) row */
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png_bytep row_buf PNG_DEPSTRUCT; /* buffer to save current
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(unfiltered) row */
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png_bytep sub_row PNG_DEPSTRUCT; /* buffer to save "sub" row
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when filtering */
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png_bytep up_row PNG_DEPSTRUCT; /* buffer to save "up" row
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when filtering */
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png_bytep avg_row PNG_DEPSTRUCT; /* buffer to save "avg" row
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when filtering */
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png_bytep paeth_row PNG_DEPSTRUCT; /* buffer to save "Paeth" row
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when filtering */
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png_row_info row_info PNG_DEPSTRUCT; /* used for transformation
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routines */
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png_uint_32 idat_size PNG_DEPSTRUCT; /* current IDAT size for read */
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png_uint_32 crc PNG_DEPSTRUCT; /* current chunk CRC value */
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png_colorp palette PNG_DEPSTRUCT; /* palette from the input file */
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png_uint_16 num_palette PNG_DEPSTRUCT; /* number of color entries in
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palette */
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png_uint_16 num_trans PNG_DEPSTRUCT; /* number of transparency values */
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png_byte chunk_name[5] PNG_DEPSTRUCT; /* null-terminated name of current
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chunk */
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png_byte compression PNG_DEPSTRUCT; /* file compression type
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(always 0) */
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png_byte filter PNG_DEPSTRUCT; /* file filter type (always 0) */
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png_byte interlaced PNG_DEPSTRUCT; /* PNG_INTERLACE_NONE,
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PNG_INTERLACE_ADAM7 */
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png_byte pass PNG_DEPSTRUCT; /* current interlace pass (0 - 6) */
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png_byte do_filter PNG_DEPSTRUCT; /* row filter flags (see
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PNG_FILTER_ below ) */
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png_byte color_type PNG_DEPSTRUCT; /* color type of file */
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png_byte bit_depth PNG_DEPSTRUCT; /* bit depth of file */
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png_byte usr_bit_depth PNG_DEPSTRUCT; /* bit depth of users row */
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png_byte pixel_depth PNG_DEPSTRUCT; /* number of bits per pixel */
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png_byte channels PNG_DEPSTRUCT; /* number of channels in file */
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png_byte usr_channels PNG_DEPSTRUCT; /* channels at start of write */
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png_byte sig_bytes PNG_DEPSTRUCT; /* magic bytes read/written from
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start of file */
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#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
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png_uint_16 filler PNG_DEPSTRUCT; /* filler bytes for pixel
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expansion */
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#endif
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#ifdef PNG_bKGD_SUPPORTED
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png_byte background_gamma_type PNG_DEPSTRUCT;
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# ifdef PNG_FLOATING_POINT_SUPPORTED
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float background_gamma PNG_DEPSTRUCT;
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# endif
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png_color_16 background PNG_DEPSTRUCT; /* background color in
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screen gamma space */
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#ifdef PNG_READ_GAMMA_SUPPORTED
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png_color_16 background_1 PNG_DEPSTRUCT; /* background normalized
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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 PNG_DEPSTRUCT; /* Function for flushing
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output */
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png_uint_32 flush_dist PNG_DEPSTRUCT; /* how many rows apart to flush,
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0 - no flush */
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png_uint_32 flush_rows PNG_DEPSTRUCT; /* number of rows written since
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last flush */
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#endif
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#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
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int gamma_shift PNG_DEPSTRUCT; /* number of "insignificant" bits
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16-bit gamma */
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#ifdef PNG_FLOATING_POINT_SUPPORTED
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float gamma PNG_DEPSTRUCT; /* file gamma value */
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float screen_gamma PNG_DEPSTRUCT; /* screen gamma value
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(display_exponent) */
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#endif
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#endif
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#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
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png_bytep gamma_table PNG_DEPSTRUCT; /* gamma table for 8-bit
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depth files */
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png_bytep gamma_from_1 PNG_DEPSTRUCT; /* converts from 1.0 to screen */
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png_bytep gamma_to_1 PNG_DEPSTRUCT; /* converts from file to 1.0 */
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png_uint_16pp gamma_16_table PNG_DEPSTRUCT; /* gamma table for 16-bit
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depth files */
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png_uint_16pp gamma_16_from_1 PNG_DEPSTRUCT; /* converts from 1.0 to
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screen */
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png_uint_16pp gamma_16_to_1 PNG_DEPSTRUCT; /* converts from file to 1.0 */
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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 PNG_DEPSTRUCT; /* significant bits in each
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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 PNG_DEPSTRUCT; /* shift for significant bit
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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 PNG_DEPSTRUCT; /* alpha values for
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paletted files */
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png_color_16 trans_color PNG_DEPSTRUCT; /* transparent color for
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non-paletted files */
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#endif
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png_read_status_ptr read_row_fn PNG_DEPSTRUCT; /* called after each
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row is decoded */
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png_write_status_ptr write_row_fn PNG_DEPSTRUCT; /* called after each
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row is encoded */
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#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
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png_progressive_info_ptr info_fn PNG_DEPSTRUCT; /* called after header
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data fully read */
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png_progressive_row_ptr row_fn PNG_DEPSTRUCT; /* called after each
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prog. row is decoded */
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png_progressive_end_ptr end_fn PNG_DEPSTRUCT; /* called after image
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is complete */
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png_bytep save_buffer_ptr PNG_DEPSTRUCT; /* current location in
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save_buffer */
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png_bytep save_buffer PNG_DEPSTRUCT; /* buffer for previously
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read data */
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png_bytep current_buffer_ptr PNG_DEPSTRUCT; /* current location in
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current_buffer */
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png_bytep current_buffer PNG_DEPSTRUCT; /* buffer for recently
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used data */
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png_uint_32 push_length PNG_DEPSTRUCT; /* size of current input
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chunk */
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png_uint_32 skip_length PNG_DEPSTRUCT; /* bytes to skip in
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input data */
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png_size_t save_buffer_size PNG_DEPSTRUCT; /* amount of data now
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in save_buffer */
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png_size_t save_buffer_max PNG_DEPSTRUCT; /* total size of
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save_buffer */
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png_size_t buffer_size PNG_DEPSTRUCT; /* total amount of
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available input data */
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png_size_t current_buffer_size PNG_DEPSTRUCT; /* amount of data now
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in current_buffer */
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int process_mode PNG_DEPSTRUCT; /* what push library
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is currently doing */
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int cur_palette PNG_DEPSTRUCT; /* current push library
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palette index */
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# ifdef PNG_TEXT_SUPPORTED
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png_size_t current_text_size PNG_DEPSTRUCT; /* current size of
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text input data */
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png_size_t current_text_left PNG_DEPSTRUCT; /* how much text left
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to read in input */
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png_charp current_text PNG_DEPSTRUCT; /* current text chunk
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buffer */
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png_charp current_text_ptr PNG_DEPSTRUCT; /* current location
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in current_text */
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# endif /* PNG_PROGRESSIVE_READ_SUPPORTED && PNG_TEXT_SUPPORTED */
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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 PNG_DEPSTRUCT;
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png_bytep offset_table PNG_DEPSTRUCT;
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png_uint_16 offset_table_number PNG_DEPSTRUCT;
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png_uint_16 offset_table_count PNG_DEPSTRUCT;
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png_uint_16 offset_table_count_free PNG_DEPSTRUCT;
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#endif
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#ifdef PNG_READ_DITHER_SUPPORTED
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png_bytep palette_lookup PNG_DEPSTRUCT; /* lookup table for dithering */
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png_bytep dither_index PNG_DEPSTRUCT; /* index translation for palette
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files */
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#endif
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#if defined(PNG_READ_DITHER_SUPPORTED) || defined(PNG_hIST_SUPPORTED)
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png_uint_16p hist PNG_DEPSTRUCT; /* histogram */
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#endif
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#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
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png_byte heuristic_method PNG_DEPSTRUCT; /* heuristic for row
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filter selection */
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png_byte num_prev_filters PNG_DEPSTRUCT; /* number of weights
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for previous rows */
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png_bytep prev_filters PNG_DEPSTRUCT; /* filter type(s) of
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previous row(s) */
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png_uint_16p filter_weights PNG_DEPSTRUCT; /* weight(s) for previous
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line(s) */
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png_uint_16p inv_filter_weights PNG_DEPSTRUCT; /* 1/weight(s) for
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previous line(s) */
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png_uint_16p filter_costs PNG_DEPSTRUCT; /* relative filter
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calculation cost */
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png_uint_16p inv_filter_costs PNG_DEPSTRUCT; /* 1/relative filter
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calculation cost */
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#endif
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#ifdef PNG_TIME_RFC1123_SUPPORTED
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png_charp time_buffer PNG_DEPSTRUCT; /* 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 PNG_DEPSTRUCT; /* flags items libpng is
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responsible for freeing */
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#ifdef PNG_USER_CHUNKS_SUPPORTED
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png_voidp user_chunk_ptr PNG_DEPSTRUCT;
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png_user_chunk_ptr read_user_chunk_fn PNG_DEPSTRUCT; /* user read
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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 PNG_DEPSTRUCT;
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png_bytep chunk_list PNG_DEPSTRUCT;
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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 PNG_DEPSTRUCT;
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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 PNG_DEPSTRUCT;
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png_uint_16 rgb_to_gray_green_coeff PNG_DEPSTRUCT;
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png_uint_16 rgb_to_gray_blue_coeff PNG_DEPSTRUCT;
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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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defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
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defined(PNG_WRITE_EMPTY_PLTE_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 PNG_DEPSTRUCT;
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#endif
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/* New member added in libpng-1.0.7 */
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#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
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png_fixed_point int_gamma PNG_DEPSTRUCT;
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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 PNG_DEPSTRUCT;
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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 PNG_DEPSTRUCT; /* user supplied struct for
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mem functions */
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png_malloc_ptr malloc_fn PNG_DEPSTRUCT; /* function for
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allocating memory */
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png_free_ptr free_fn PNG_DEPSTRUCT; /* function for
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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 PNG_DEPSTRUCT; /* buffer to save current
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(unfiltered) row */
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#ifdef PNG_READ_DITHER_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 dither_sort PNG_DEPSTRUCT; /* working sort array */
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png_bytep index_to_palette PNG_DEPSTRUCT; /* where the original
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index currently is
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in the palette */
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png_bytep palette_to_index PNG_DEPSTRUCT; /* which original index
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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 PNG_DEPSTRUCT;
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#ifdef PNG_USER_LIMITS_SUPPORTED
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png_uint_32 user_width_max PNG_DEPSTRUCT;
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png_uint_32 user_height_max PNG_DEPSTRUCT;
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/* Added in libpng-1.4.0: Total number of sPLT, text, and unknown
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* chunks that can be stored (0 means unlimited).
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*/
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png_uint_32 user_chunk_cache_max PNG_DEPSTRUCT;
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/* Total memory that a zTXt, sPLT, iTXt, iCCP, or unknown chunk
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* can occupy when decompressed. 0 means unlimited.
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*/
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png_uint_32 user_chunk_malloc_max PNG_DEPSTRUCT;
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#endif
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/* New member added in libpng-1.0.25 and 1.2.17 */
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#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
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/* Storage for unknown chunk that the library doesn't recognize. */
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png_unknown_chunk unknown_chunk PNG_DEPSTRUCT;
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#endif
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/* New members added in libpng-1.2.26 */
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png_uint_32 old_big_row_buf_size PNG_DEPSTRUCT;
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png_uint_32 old_prev_row_size PNG_DEPSTRUCT;
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/* New member added in libpng-1.2.30 */
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png_charp chunkdata PNG_DEPSTRUCT; /* buffer for reading chunk data */
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#ifdef PNG_IO_STATE_SUPPORTED
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/* New member added in libpng-1.4.0 */
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png_uint_32 io_state PNG_DEPSTRUCT;
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#endif
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};
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