michael@0: 
michael@0: /* pngstruct.h - header file for PNG reference library
michael@0:  *
michael@0:  * Copyright (c) 1998-2013 Glenn Randers-Pehrson
michael@0:  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
michael@0:  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
michael@0:  *
michael@0:  * Last changed in libpng 1.6.1 [March 28, 2013]
michael@0:  *
michael@0:  * This code is released under the libpng license.
michael@0:  * For conditions of distribution and use, see the disclaimer
michael@0:  * and license in png.h
michael@0:  */
michael@0: 
michael@0: /* The structure that holds the information to read and write PNG files.
michael@0:  * The only people who need to care about what is inside of this are the
michael@0:  * people who will be modifying the library for their own special needs.
michael@0:  * It should NOT be accessed directly by an application.
michael@0:  */
michael@0: 
michael@0: #ifndef PNGSTRUCT_H
michael@0: #define PNGSTRUCT_H
michael@0: /* zlib.h defines the structure z_stream, an instance of which is included
michael@0:  * in this structure and is required for decompressing the LZ compressed
michael@0:  * data in PNG files.
michael@0:  */
michael@0: #ifndef ZLIB_CONST
michael@0:    /* We must ensure that zlib uses 'const' in declarations. */
michael@0: #  define ZLIB_CONST
michael@0: #endif
michael@0: #include "zlib.h"
michael@0: #ifdef const
michael@0:    /* zlib.h sometimes #defines const to nothing, undo this. */
michael@0: #  undef const
michael@0: #endif
michael@0: 
michael@0: /* zlib.h has mediocre z_const use before 1.2.6, this stuff is for compatibility
michael@0:  * with older builds.
michael@0:  */
michael@0: #if ZLIB_VERNUM < 0x1260
michael@0: #  define PNGZ_MSG_CAST(s) png_constcast(char*,s)
michael@0: #  define PNGZ_INPUT_CAST(b) png_constcast(png_bytep,b)
michael@0: #else
michael@0: #  define PNGZ_MSG_CAST(s) (s)
michael@0: #  define PNGZ_INPUT_CAST(b) (b)
michael@0: #endif
michael@0: 
michael@0: /* zlib.h declares a magic type 'uInt' that limits the amount of data that zlib
michael@0:  * can handle at once.  This type need be no larger than 16 bits (so maximum of
michael@0:  * 65535), this define allows us to discover how big it is, but limited by the
michael@0:  * maximuum for png_size_t.  The value can be overriden in a library build
michael@0:  * (pngusr.h, or set it in CPPFLAGS) and it works to set it to a considerably
michael@0:  * lower value (e.g. 255 works).  A lower value may help memory usage (slightly)
michael@0:  * and may even improve performance on some systems (and degrade it on others.)
michael@0:  */
michael@0: #ifndef ZLIB_IO_MAX
michael@0: #  define ZLIB_IO_MAX ((uInt)-1)
michael@0: #endif
michael@0: 
michael@0: #ifdef PNG_WRITE_SUPPORTED
michael@0: /* The type of a compression buffer list used by the write code. */
michael@0: typedef struct png_compression_buffer
michael@0: {
michael@0:    struct png_compression_buffer *next;
michael@0:    png_byte                       output[1]; /* actually zbuf_size */
michael@0: } png_compression_buffer, *png_compression_bufferp;
michael@0: 
michael@0: #define PNG_COMPRESSION_BUFFER_SIZE(pp)\
michael@0:    (offsetof(png_compression_buffer, output) + (pp)->zbuffer_size)
michael@0: #endif
michael@0: 
michael@0: /* Colorspace support; structures used in png_struct, png_info and in internal
michael@0:  * functions to hold and communicate information about the color space.
michael@0:  *
michael@0:  * PNG_COLORSPACE_SUPPORTED is only required if the application will perform
michael@0:  * colorspace corrections, otherwise all the colorspace information can be
michael@0:  * skipped and the size of libpng can be reduced (significantly) by compiling
michael@0:  * out the colorspace support.
michael@0:  */
michael@0: #ifdef PNG_COLORSPACE_SUPPORTED
michael@0: /* The chromaticities of the red, green and blue colorants and the chromaticity
michael@0:  * of the corresponding white point (i.e. of rgb(1.0,1.0,1.0)).
michael@0:  */
michael@0: typedef struct png_xy
michael@0: {
michael@0:    png_fixed_point redx, redy;
michael@0:    png_fixed_point greenx, greeny;
michael@0:    png_fixed_point bluex, bluey;
michael@0:    png_fixed_point whitex, whitey;
michael@0: } png_xy;
michael@0: 
michael@0: /* The same data as above but encoded as CIE XYZ values.  When this data comes
michael@0:  * from chromaticities the sum of the Y values is assumed to be 1.0
michael@0:  */
michael@0: typedef struct png_XYZ
michael@0: {
michael@0:    png_fixed_point red_X, red_Y, red_Z;
michael@0:    png_fixed_point green_X, green_Y, green_Z;
michael@0:    png_fixed_point blue_X, blue_Y, blue_Z;
michael@0: } png_XYZ;
michael@0: #endif /* COLORSPACE */
michael@0: 
michael@0: #if defined(PNG_COLORSPACE_SUPPORTED) || defined(PNG_GAMMA_SUPPORTED)
michael@0: /* A colorspace is all the above plus, potentially, profile information,
michael@0:  * however at present libpng does not use the profile internally so it is only
michael@0:  * stored in the png_info struct (if iCCP is supported.)  The rendering intent
michael@0:  * is retained here and is checked.
michael@0:  *
michael@0:  * The file gamma encoding information is also stored here and gamma correction
michael@0:  * is done by libpng, whereas color correction must currently be done by the
michael@0:  * application.
michael@0:  */
michael@0: typedef struct png_colorspace
michael@0: {
michael@0: #ifdef PNG_GAMMA_SUPPORTED
michael@0:    png_fixed_point gamma;        /* File gamma */
michael@0: #endif
michael@0: 
michael@0: #ifdef PNG_COLORSPACE_SUPPORTED
michael@0:    png_xy      end_points_xy;    /* End points as chromaticities */
michael@0:    png_XYZ     end_points_XYZ;   /* End points as CIE XYZ colorant values */
michael@0:    png_uint_16 rendering_intent; /* Rendering intent of a profile */
michael@0: #endif
michael@0: 
michael@0:    /* Flags are always defined to simplify the code. */
michael@0:    png_uint_16 flags;            /* As defined below */
michael@0: } png_colorspace, * PNG_RESTRICT png_colorspacerp;
michael@0: 
michael@0: typedef const png_colorspace * PNG_RESTRICT png_const_colorspacerp;
michael@0: 
michael@0: /* General flags for the 'flags' field */
michael@0: #define PNG_COLORSPACE_HAVE_GAMMA           0x0001
michael@0: #define PNG_COLORSPACE_HAVE_ENDPOINTS       0x0002
michael@0: #define PNG_COLORSPACE_HAVE_INTENT          0x0004
michael@0: #define PNG_COLORSPACE_FROM_gAMA            0x0008
michael@0: #define PNG_COLORSPACE_FROM_cHRM            0x0010
michael@0: #define PNG_COLORSPACE_FROM_sRGB            0x0020
michael@0: #define PNG_COLORSPACE_ENDPOINTS_MATCH_sRGB 0x0040
michael@0: #define PNG_COLORSPACE_MATCHES_sRGB         0x0080 /* exact match on profile */
michael@0: #define PNG_COLORSPACE_INVALID              0x8000
michael@0: #define PNG_COLORSPACE_CANCEL(flags)        (0xffff ^ (flags))
michael@0: #endif /* COLORSPACE || GAMMA */
michael@0: 
michael@0: struct png_struct_def
michael@0: {
michael@0: #ifdef PNG_SETJMP_SUPPORTED
michael@0:    jmp_buf jmp_buf_local;     /* New name in 1.6.0 for jmp_buf in png_struct */
michael@0:    png_longjmp_ptr longjmp_fn;/* setjmp non-local goto function. */
michael@0:    jmp_buf *jmp_buf_ptr;      /* passed to longjmp_fn */
michael@0:    size_t jmp_buf_size;       /* size of the above, if allocated */
michael@0: #endif
michael@0:    png_error_ptr error_fn;    /* function for printing errors and aborting */
michael@0: #ifdef PNG_WARNINGS_SUPPORTED
michael@0:    png_error_ptr warning_fn;  /* function for printing warnings */
michael@0: #endif
michael@0:    png_voidp error_ptr;       /* user supplied struct for error functions */
michael@0:    png_rw_ptr write_data_fn;  /* function for writing output data */
michael@0:    png_rw_ptr read_data_fn;   /* function for reading input data */
michael@0:    png_voidp io_ptr;          /* ptr to application struct for I/O functions */
michael@0: 
michael@0: #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
michael@0:    png_user_transform_ptr read_user_transform_fn; /* user read transform */
michael@0: #endif
michael@0: 
michael@0: #ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
michael@0:    png_user_transform_ptr write_user_transform_fn; /* user write transform */
michael@0: #endif
michael@0: 
michael@0: /* These were added in libpng-1.0.2 */
michael@0: #ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
michael@0: #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
michael@0:     defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
michael@0:    png_voidp user_transform_ptr; /* user supplied struct for user transform */
michael@0:    png_byte user_transform_depth;    /* bit depth of user transformed pixels */
michael@0:    png_byte user_transform_channels; /* channels in user transformed pixels */
michael@0: #endif
michael@0: #endif
michael@0: 
michael@0:    png_uint_32 mode;          /* tells us where we are in the PNG file */
michael@0:    png_uint_32 flags;         /* flags indicating various things to libpng */
michael@0:    png_uint_32 transformations; /* which transformations to perform */
michael@0: 
michael@0:    png_uint_32 zowner;        /* ID (chunk type) of zstream owner, 0 if none */
michael@0:    z_stream    zstream;       /* decompression structure */
michael@0: 
michael@0: #ifdef PNG_WRITE_SUPPORTED
michael@0:    png_compression_bufferp zbuffer_list; /* Created on demand during write */
michael@0:    uInt                    zbuffer_size; /* size of the actual buffer */
michael@0: 
michael@0:    int zlib_level;            /* holds zlib compression level */
michael@0:    int zlib_method;           /* holds zlib compression method */
michael@0:    int zlib_window_bits;      /* holds zlib compression window bits */
michael@0:    int zlib_mem_level;        /* holds zlib compression memory level */
michael@0:    int zlib_strategy;         /* holds zlib compression strategy */
michael@0: #endif
michael@0: /* Added at libpng 1.5.4 */
michael@0: #ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
michael@0:    int zlib_text_level;            /* holds zlib compression level */
michael@0:    int zlib_text_method;           /* holds zlib compression method */
michael@0:    int zlib_text_window_bits;      /* holds zlib compression window bits */
michael@0:    int zlib_text_mem_level;        /* holds zlib compression memory level */
michael@0:    int zlib_text_strategy;         /* holds zlib compression strategy */
michael@0: #endif
michael@0: /* End of material added at libpng 1.5.4 */
michael@0: /* Added at libpng 1.6.0 */
michael@0: #ifdef PNG_WRITE_SUPPORTED
michael@0:    int zlib_set_level;        /* Actual values set into the zstream on write */
michael@0:    int zlib_set_method;
michael@0:    int zlib_set_window_bits;
michael@0:    int zlib_set_mem_level;
michael@0:    int zlib_set_strategy;
michael@0: #endif
michael@0: 
michael@0:    png_uint_32 width;         /* width of image in pixels */
michael@0:    png_uint_32 height;        /* height of image in pixels */
michael@0:    png_uint_32 num_rows;      /* number of rows in current pass */
michael@0:    png_uint_32 usr_width;     /* width of row at start of write */
michael@0:    png_size_t rowbytes;       /* size of row in bytes */
michael@0:    png_uint_32 iwidth;        /* width of current interlaced row in pixels */
michael@0:    png_uint_32 row_number;    /* current row in interlace pass */
michael@0:    png_uint_32 chunk_name;    /* PNG_CHUNK() id of current chunk */
michael@0:    png_bytep prev_row;        /* buffer to save previous (unfiltered) row.
michael@0:                                * This is a pointer into big_prev_row
michael@0:                                */
michael@0:    png_bytep row_buf;         /* buffer to save current (unfiltered) row.
michael@0:                                * This is a pointer into big_row_buf
michael@0:                                */
michael@0: #ifdef PNG_WRITE_SUPPORTED
michael@0:    png_bytep sub_row;         /* buffer to save "sub" row when filtering */
michael@0:    png_bytep up_row;          /* buffer to save "up" row when filtering */
michael@0:    png_bytep avg_row;         /* buffer to save "avg" row when filtering */
michael@0:    png_bytep paeth_row;       /* buffer to save "Paeth" row when filtering */
michael@0: #endif
michael@0:    png_size_t info_rowbytes;  /* Added in 1.5.4: cache of updated row bytes */
michael@0: 
michael@0:    png_uint_32 idat_size;     /* current IDAT size for read */
michael@0:    png_uint_32 crc;           /* current chunk CRC value */
michael@0:    png_colorp palette;        /* palette from the input file */
michael@0:    png_uint_16 num_palette;   /* number of color entries in palette */
michael@0: 
michael@0: /* Added at libpng-1.5.10 */
michael@0: #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
michael@0:    int num_palette_max;       /* maximum palette index found in IDAT */
michael@0: #endif
michael@0: 
michael@0:    png_uint_16 num_trans;     /* number of transparency values */
michael@0:    png_byte compression;      /* file compression type (always 0) */
michael@0:    png_byte filter;           /* file filter type (always 0) */
michael@0:    png_byte interlaced;       /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
michael@0:    png_byte pass;             /* current interlace pass (0 - 6) */
michael@0:    png_byte do_filter;        /* row filter flags (see PNG_FILTER_ below ) */
michael@0:    png_byte color_type;       /* color type of file */
michael@0:    png_byte bit_depth;        /* bit depth of file */
michael@0:    png_byte usr_bit_depth;    /* bit depth of users row: write only */
michael@0:    png_byte pixel_depth;      /* number of bits per pixel */
michael@0:    png_byte channels;         /* number of channels in file */
michael@0: #ifdef PNG_WRITE_SUPPORTED
michael@0:    png_byte usr_channels;     /* channels at start of write: write only */
michael@0: #endif
michael@0:    png_byte sig_bytes;        /* magic bytes read/written from start of file */
michael@0:    png_byte maximum_pixel_depth;
michael@0:                               /* pixel depth used for the row buffers */
michael@0:    png_byte transformed_pixel_depth;
michael@0:                               /* pixel depth after read/write transforms */
michael@0: #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
michael@0:    png_uint_16 filler;           /* filler bytes for pixel expansion */
michael@0: #endif
michael@0: 
michael@0: #if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
michael@0:    defined(PNG_READ_ALPHA_MODE_SUPPORTED)
michael@0:    png_byte background_gamma_type;
michael@0:    png_fixed_point background_gamma;
michael@0:    png_color_16 background;   /* background color in screen gamma space */
michael@0: #ifdef PNG_READ_GAMMA_SUPPORTED
michael@0:    png_color_16 background_1; /* background normalized to gamma 1.0 */
michael@0: #endif
michael@0: #endif /* PNG_bKGD_SUPPORTED */
michael@0: 
michael@0: #ifdef PNG_WRITE_FLUSH_SUPPORTED
michael@0:    png_flush_ptr output_flush_fn; /* Function for flushing output */
michael@0:    png_uint_32 flush_dist;    /* how many rows apart to flush, 0 - no flush */
michael@0:    png_uint_32 flush_rows;    /* number of rows written since last flush */
michael@0: #endif
michael@0: 
michael@0: #ifdef PNG_READ_GAMMA_SUPPORTED
michael@0:    int gamma_shift;      /* number of "insignificant" bits in 16-bit gamma */
michael@0:    png_fixed_point screen_gamma; /* screen gamma value (display_exponent) */
michael@0: 
michael@0:    png_bytep gamma_table;     /* gamma table for 8-bit depth files */
michael@0:    png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
michael@0: #if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
michael@0:    defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
michael@0:    defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
michael@0:    png_bytep gamma_from_1;    /* converts from 1.0 to screen */
michael@0:    png_bytep gamma_to_1;      /* converts from file to 1.0 */
michael@0:    png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
michael@0:    png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
michael@0: #endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
michael@0: #endif
michael@0: 
michael@0: #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)
michael@0:    png_color_8 sig_bit;       /* significant bits in each available channel */
michael@0: #endif
michael@0: 
michael@0: #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
michael@0:    png_color_8 shift;         /* shift for significant bit tranformation */
michael@0: #endif
michael@0: 
michael@0: #if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
michael@0:  || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
michael@0:    png_bytep trans_alpha;           /* alpha values for paletted files */
michael@0:    png_color_16 trans_color;  /* transparent color for non-paletted files */
michael@0: #endif
michael@0: 
michael@0:    png_read_status_ptr read_row_fn;   /* called after each row is decoded */
michael@0:    png_write_status_ptr write_row_fn; /* called after each row is encoded */
michael@0: #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
michael@0:    png_progressive_info_ptr info_fn; /* called after header data fully read */
michael@0:    png_progressive_row_ptr row_fn;   /* called after a prog. row is decoded */
michael@0:    png_progressive_end_ptr end_fn;   /* called after image is complete */
michael@0:    png_bytep save_buffer_ptr;        /* current location in save_buffer */
michael@0:    png_bytep save_buffer;            /* buffer for previously read data */
michael@0:    png_bytep current_buffer_ptr;     /* current location in current_buffer */
michael@0:    png_bytep current_buffer;         /* buffer for recently used data */
michael@0:    png_uint_32 push_length;          /* size of current input chunk */
michael@0:    png_uint_32 skip_length;          /* bytes to skip in input data */
michael@0:    png_size_t save_buffer_size;      /* amount of data now in save_buffer */
michael@0:    png_size_t save_buffer_max;       /* total size of save_buffer */
michael@0:    png_size_t buffer_size;           /* total amount of available input data */
michael@0:    png_size_t current_buffer_size;   /* amount of data now in current_buffer */
michael@0:    int process_mode;                 /* what push library is currently doing */
michael@0:    int cur_palette;                  /* current push library palette index */
michael@0: 
michael@0: #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
michael@0: 
michael@0: #if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
michael@0: /* For the Borland special 64K segment handler */
michael@0:    png_bytepp offset_table_ptr;
michael@0:    png_bytep offset_table;
michael@0:    png_uint_16 offset_table_number;
michael@0:    png_uint_16 offset_table_count;
michael@0:    png_uint_16 offset_table_count_free;
michael@0: #endif
michael@0: 
michael@0: #ifdef PNG_READ_QUANTIZE_SUPPORTED
michael@0:    png_bytep palette_lookup; /* lookup table for quantizing */
michael@0:    png_bytep quantize_index; /* index translation for palette files */
michael@0: #endif
michael@0: 
michael@0: #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
michael@0:    png_byte heuristic_method;        /* heuristic for row filter selection */
michael@0:    png_byte num_prev_filters;        /* number of weights for previous rows */
michael@0:    png_bytep prev_filters;           /* filter type(s) of previous row(s) */
michael@0:    png_uint_16p filter_weights;      /* weight(s) for previous line(s) */
michael@0:    png_uint_16p inv_filter_weights;  /* 1/weight(s) for previous line(s) */
michael@0:    png_uint_16p filter_costs;        /* relative filter calculation cost */
michael@0:    png_uint_16p inv_filter_costs;    /* 1/relative filter calculation cost */
michael@0: #endif
michael@0: 
michael@0:    /* Options */
michael@0: #ifdef PNG_SET_OPTION_SUPPORTED
michael@0:    png_byte options;           /* On/off state (up to 4 options) */
michael@0: #endif
michael@0: 
michael@0: #if PNG_LIBPNG_VER < 10700
michael@0: /* To do: remove this from libpng-1.7 */
michael@0: #ifdef PNG_TIME_RFC1123_SUPPORTED
michael@0:    char time_buffer[29]; /* String to hold RFC 1123 time text */
michael@0: #endif
michael@0: #endif
michael@0: 
michael@0: /* New members added in libpng-1.0.6 */
michael@0: 
michael@0:    png_uint_32 free_me;    /* flags items libpng is responsible for freeing */
michael@0: 
michael@0: #ifdef PNG_USER_CHUNKS_SUPPORTED
michael@0:    png_voidp user_chunk_ptr;
michael@0: #ifdef PNG_READ_USER_CHUNKS_SUPPORTED
michael@0:    png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */
michael@0: #endif
michael@0: #endif
michael@0: 
michael@0: #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
michael@0:    int          unknown_default; /* As PNG_HANDLE_* */
michael@0:    unsigned int num_chunk_list;  /* Number of entries in the list */
michael@0:    png_bytep    chunk_list;      /* List of png_byte[5]; the textual chunk name
michael@0:                                   * followed by a PNG_HANDLE_* byte */
michael@0: #endif
michael@0: 
michael@0: /* New members added in libpng-1.0.3 */
michael@0: #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
michael@0:    png_byte rgb_to_gray_status;
michael@0:    /* Added in libpng 1.5.5 to record setting of coefficients: */
michael@0:    png_byte rgb_to_gray_coefficients_set;
michael@0:    /* These were changed from png_byte in libpng-1.0.6 */
michael@0:    png_uint_16 rgb_to_gray_red_coeff;
michael@0:    png_uint_16 rgb_to_gray_green_coeff;
michael@0:    /* deleted in 1.5.5: rgb_to_gray_blue_coeff; */
michael@0: #endif
michael@0: 
michael@0: /* New member added in libpng-1.0.4 (renamed in 1.0.9) */
michael@0: #if defined(PNG_MNG_FEATURES_SUPPORTED)
michael@0: /* Changed from png_byte to png_uint_32 at version 1.2.0 */
michael@0:    png_uint_32 mng_features_permitted;
michael@0: #endif
michael@0: 
michael@0: /* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */
michael@0: #ifdef PNG_MNG_FEATURES_SUPPORTED
michael@0:    png_byte filter_type;
michael@0: #endif
michael@0: 
michael@0: #ifdef PNG_APNG_SUPPORTED
michael@0:    png_uint_32 apng_flags;
michael@0:    png_uint_32 next_seq_num;         /* next fcTL/fdAT chunk sequence number */
michael@0:    png_uint_32 first_frame_width;
michael@0:    png_uint_32 first_frame_height;
michael@0: 
michael@0: #ifdef PNG_READ_APNG_SUPPORTED
michael@0:    png_uint_32 num_frames_read;      /* incremented after all image data of */
michael@0:                                      /* a frame is read */
michael@0: #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
michael@0:    png_progressive_frame_ptr frame_info_fn; /* frame info read callback */
michael@0:    png_progressive_frame_ptr frame_end_fn;  /* frame data read callback */
michael@0: #endif
michael@0: #endif
michael@0: 
michael@0: #ifdef PNG_WRITE_APNG_SUPPORTED
michael@0:    png_uint_32 num_frames_to_write;
michael@0:    png_uint_32 num_frames_written;
michael@0: #endif
michael@0: #endif /* PNG_APNG_SUPPORTED */
michael@0: 
michael@0: /* New members added in libpng-1.2.0 */
michael@0: 
michael@0: /* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
michael@0: #ifdef PNG_USER_MEM_SUPPORTED
michael@0:    png_voidp mem_ptr;             /* user supplied struct for mem functions */
michael@0:    png_malloc_ptr malloc_fn;      /* function for allocating memory */
michael@0:    png_free_ptr free_fn;          /* function for freeing memory */
michael@0: #endif
michael@0: 
michael@0: /* New member added in libpng-1.0.13 and 1.2.0 */
michael@0:    png_bytep big_row_buf;         /* buffer to save current (unfiltered) row */
michael@0: 
michael@0: #ifdef PNG_READ_QUANTIZE_SUPPORTED
michael@0: /* The following three members were added at version 1.0.14 and 1.2.4 */
michael@0:    png_bytep quantize_sort;          /* working sort array */
michael@0:    png_bytep index_to_palette;       /* where the original index currently is
michael@0:                                         in the palette */
michael@0:    png_bytep palette_to_index;       /* which original index points to this
michael@0:                                          palette color */
michael@0: #endif
michael@0: 
michael@0: /* New members added in libpng-1.0.16 and 1.2.6 */
michael@0:    png_byte compression_type;
michael@0: 
michael@0: #ifdef PNG_USER_LIMITS_SUPPORTED
michael@0:    png_uint_32 user_width_max;
michael@0:    png_uint_32 user_height_max;
michael@0: 
michael@0:    /* Added in libpng-1.4.0: Total number of sPLT, text, and unknown
michael@0:     * chunks that can be stored (0 means unlimited).
michael@0:     */
michael@0:    png_uint_32 user_chunk_cache_max;
michael@0: 
michael@0:    /* Total memory that a zTXt, sPLT, iTXt, iCCP, or unknown chunk
michael@0:     * can occupy when decompressed.  0 means unlimited.
michael@0:     */
michael@0:    png_alloc_size_t user_chunk_malloc_max;
michael@0: #endif
michael@0: 
michael@0: /* New member added in libpng-1.0.25 and 1.2.17 */
michael@0: #ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
michael@0:    /* Temporary storage for unknown chunk that the library doesn't recognize,
michael@0:     * used while reading the chunk.
michael@0:     */
michael@0:    png_unknown_chunk unknown_chunk;
michael@0: #endif
michael@0: 
michael@0: /* New member added in libpng-1.2.26 */
michael@0:   png_size_t old_big_row_buf_size;
michael@0: 
michael@0: #ifdef PNG_READ_SUPPORTED
michael@0: /* New member added in libpng-1.2.30 */
michael@0:   png_bytep        read_buffer;      /* buffer for reading chunk data */
michael@0:   png_alloc_size_t read_buffer_size; /* current size of the buffer */
michael@0: #endif
michael@0: #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
michael@0:   uInt             IDAT_read_size;   /* limit on read buffer size for IDAT */
michael@0: #endif
michael@0: 
michael@0: #ifdef PNG_IO_STATE_SUPPORTED
michael@0: /* New member added in libpng-1.4.0 */
michael@0:    png_uint_32 io_state;
michael@0: #endif
michael@0: 
michael@0: /* New member added in libpng-1.5.6 */
michael@0:    png_bytep big_prev_row;
michael@0: 
michael@0: /* New member added in libpng-1.5.7 */
michael@0:    void (*read_filter[PNG_FILTER_VALUE_LAST-1])(png_row_infop row_info,
michael@0:       png_bytep row, png_const_bytep prev_row);
michael@0: 
michael@0: #ifdef PNG_READ_SUPPORTED
michael@0: #if defined(PNG_COLORSPACE_SUPPORTED) || defined(PNG_GAMMA_SUPPORTED)
michael@0:    png_colorspace   colorspace;
michael@0: #endif
michael@0: #endif
michael@0: };
michael@0: #endif /* PNGSTRUCT_H */