pngdef.pas

Linux下的基于X11的图形开发环境。

unit pngdef;

// Caution: this file has fallen out of date since version 1.0.5.  Write to
// [e-mail] or to [e-mail] about volunteering
// to it up to date.

interface

const
  PNG_LIBPNG_VER_STRING = '1.2.5';
  PNG_LIBPNG_VER        =  10205;

type
  png_uint_32 = Cardinal;
  png_int_32  = Longint;
  png_uint_16 = Word;
  png_int_16  = Smallint;
  png_byte    = Byte;
  png_size_t  = png_uint_32;
  png_charpp  = ^png_charp;
  png_charp   = PChar;
  float       = single;
  int         = Integer;
  png_bytepp  = ^png_bytep;
  png_bytep   = ^png_byte;
  png_uint_16p = ^png_uint_16;
  png_uint_16pp = ^png_uint_16p;
  png_voidp    = pointer;
  time_t       = Longint;
  png_doublep  = ^png_double;
  png_double   = double;

  user_error_ptr  = Pointer;
  png_error_ptrp = ^png_error_ptr;
  png_error_ptr  = procedure(png_ptr: Pointer; msg: Pointer);
             stdcall;
  png_rw_ptrp = ^png_rw_ptr;
  png_rw_ptr = procedure(png_ptr: Pointer; data: Pointer;
                         length: png_size_t);
             stdcall;
  png_flush_ptrp = ^png_flush_ptr;
  png_flush_ptr = procedure(png_ptr: Pointer);
             stdcall;
  png_progressive_info_ptrp = ^png_progressive_info_ptr;
  png_progressive_info_ptr  = procedure(png_ptr: Pointer;
                                        info_ptr: Pointer);
             stdcall;
  png_progressive_end_ptrp  = ^png_progressive_end_ptr;
  png_progressive_end_ptr   = procedure(png_ptr: Pointer;
                                        info_ptr: Pointer);
             stdcall;
  png_progressive_row_ptrp  = ^png_progressive_row_ptr;
  png_progressive_row_ptr   = procedure(png_ptr: Pointer;
                                data: Pointer; length: png_uint_32;
                                count: int);
             stdcall;
  png_read_status_ptr = procedure(png_ptr: Pointer;
                          row_number: png_uint_32; pass: int);
             stdcall;
  png_write_status_ptr = procedure(png_ptr: Pointer;
                           row_number: png_uint_32; pass: int);
             stdcall;
  png_user_chunk_ptr = procedure(png_ptr: Pointer;
                             data: png_unknown_chunkp);
             stdcall;
  png_user_transform_ptr = procedure(png_ptr: Pointer;
                             row_info: Pointer; data: png_bytep);
             stdcall;

  png_colorpp = ^png_colorp;
  png_colorp = ^png_color;
  png_color = packed record
    red, green, blue: png_byte;
    end;

  png_color_16pp = ^png_color_16p;
  png_color_16p = ^png_color_16;
  png_color_16 = packed record
    index: png_byte;                 //used for palette files
    red, green, blue: png_uint_16;   //for use in red green blue files
    gray: png_uint_16;               //for use in grayscale files
    end;

  png_color_8pp = ^png_color_8p;
  png_color_8p = ^png_color_8;
  png_color_8 = packed record
    red, green, blue: png_byte;   //for use in red green blue files
    gray: png_byte;               //for use in grayscale files
    alpha: png_byte;              //for alpha channel files
    end;

  png_textpp = ^png_textp;
  png_textp = ^png_text;
  png_text = packed record
    compression: int;            //compression value
    key: png_charp;              //keyword, 1-79 character description of "text"
    text: png_charp;             //comment, may be empty ("")
    text_length: png_size_t;     //length of text field
    end;

  png_timepp = ^png_timep;
  png_timep = ^png_time;
  png_time = packed record
    year: png_uint_16;           //yyyy
    month: png_byte;             //1..12
    day: png_byte;               //1..31
    hour: png_byte;              //0..23
    minute: png_byte;            //0..59
    second: png_byte;            //0..60 (leap seconds)
    end;

  png_infopp = ^png_infop;
  png_infop = Pointer;

  png_row_infopp = ^png_row_infop;
  png_row_infop = ^png_row_info;
  png_row_info = packed record
    width: png_uint_32;          //width of row
    rowbytes: png_size_t;        //number of bytes in row
    color_type: png_byte;        //color type of row
    bit_depth: png_byte;         //bit depth of row
    channels: png_byte;          //number of channels (1, 2, 3, or 4)
    pixel_depth: png_byte;       //bits per pixel (depth * channels)
    end;

  png_structpp = ^png_structp;
  png_structp = Pointer;

const

// Supported compression types for text in PNG files (tEXt, and zTXt).
// The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed.

  PNG_TEXT_COMPRESSION_NONE_WR = -3;
  PNG_TEXT_COMPRESSION_zTXt_WR = -2;
  PNG_TEXT_COMPRESSION_NONE    = -1;
  PNG_TEXT_COMPRESSION_zTXt    = 0;

// These describe the color_type field in png_info.
// color type masks

  PNG_COLOR_MASK_PALETTE   = 1;
  PNG_COLOR_MASK_COLOR     = 2;
  PNG_COLOR_MASK_ALPHA     = 4;

// color types.  Note that not all combinations are legal

  PNG_COLOR_TYPE_GRAY       = 0;
  PNG_COLOR_TYPE_PALETTE    = PNG_COLOR_MASK_COLOR or
                              PNG_COLOR_MASK_PALETTE;
  PNG_COLOR_TYPE_RGB        = PNG_COLOR_MASK_COLOR;
  PNG_COLOR_TYPE_RGB_ALPHA  = PNG_COLOR_MASK_COLOR or
                              PNG_COLOR_MASK_ALPHA;
  PNG_COLOR_TYPE_GRAY_ALPHA = PNG_COLOR_MASK_ALPHA;

// This is for compression type. PNG 1.0 only defines the single type.

  PNG_COMPRESSION_TYPE_BASE    = 0;   // Deflate method 8, 32K window
  PNG_COMPRESSION_TYPE_DEFAULT = PNG_COMPRESSION_TYPE_BASE;

// This is for filter type. PNG 1.0 only defines the single type.

  PNG_FILTER_TYPE_BASE    = 0;       // Single row per-byte filtering
  PNG_FILTER_TYPE_DEFAULT = PNG_FILTER_TYPE_BASE;

// These are for the interlacing type.  These values should NOT be changed.

  PNG_INTERLACE_NONE  = 0;      // Non-interlaced image
  PNG_INTERLACE_ADAM7 = 1;      // Adam7 interlacing

// These are for the oFFs chunk.  These values should NOT be changed.

  PNG_OFFSET_PIXEL      = 0;    // Offset in pixels
  PNG_OFFSET_MICROMETER = 1;    // Offset in micrometers (1/10^6 meter)

// These are for the pCAL chunk.  These values should NOT be changed.

  PNG_EQUATION_LINEAR     = 0;  // Linear transformation
  PNG_EQUATION_BASE_E     = 1;  // Exponential base e transform
  PNG_EQUATION_ARBITRARY  = 2;  // Arbitrary base exponential transform
  PNG_EQUATION_HYPERBOLIC = 3;  // Hyperbolic sine transformation

// These are for the pHYs chunk.  These values should NOT be changed.

  PNG_RESOLUTION_UNKNOWN = 0;   // pixels/unknown unit (aspect ratio)
  PNG_RESOLUTION_METER   = 1;   // pixels/meter

// These are for the sRGB chunk.  These values should NOT be changed.
 PNG_sRGB_INTENT_PERCEPTUAL = 0;
 PNG_sRGB_INTENT_RELATIVE   = 1;
 PNG_sRGB_INTENT_SATURATION = 2;
 PNG_sRGB_INTENT_ABSOLUTE   = 3;

// Handle alpha and tRNS by replacing with a background color.
  PNG_BACKGROUND_GAMMA_UNKNOWN = 0;
  PNG_BACKGROUND_GAMMA_SCREEN  = 1;
  PNG_BACKGROUND_GAMMA_FILE    = 2;
  PNG_BACKGROUND_GAMMA_UNIQUE  = 3;

// Values for png_set_crc_action() to say how to handle CRC errors in
// ancillary and critical chunks, and whether to use the data contained
// therein.  Note that it is impossible to "discard" data in a critical
// chunk.  For versions prior to 0.90, the action was always error/quit,
// whereas in version 0.90 and later, the action for CRC errors in ancillary
// chunks is warn/discard.  These values should NOT be changed.

//      value                   action:critical     action:ancillary

  PNG_CRC_DEFAULT      = 0;  // error/quit          warn/discard data
  PNG_CRC_ERROR_QUIT   = 1;  // error/quit          error/quit
  PNG_CRC_WARN_DISCARD = 2;  // (INVALID)           warn/discard data
  PNG_CRC_WARN_USE     = 3;  // warn/use data       warn/use data
  PNG_CRC_QUIET_USE    = 4;  // quiet/use data      quiet/use data
  PNG_CRC_NO_CHANGE    = 5;  // use current value   use current value

// Flags for png_set_filter() to say which filters to use.  The flags
// are chosen so that they don't conflict with real filter types
// below, in case they are supplied instead of the #defined constants.
// These values should NOT be changed.

  PNG_NO_FILTERS   = $00;
  PNG_FILTER_NONE  = $08;
  PNG_FILTER_SUB   = $10;
  PNG_FILTER_UP    = $20;
  PNG_FILTER_AVG   = $40;
  PNG_FILTER_PAETH = $80;
  PNG_ALL_FILTERS  = PNG_FILTER_NONE or PNG_FILTER_SUB or
                     PNG_FILTER_UP   or PNG_FILTER_AVG or
                     PNG_FILTER_PAETH;

// Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
// These defines should NOT be changed.

  PNG_FILTER_VALUE_NONE  = 0;
  PNG_FILTER_VALUE_SUB   = 1;
  PNG_FILTER_VALUE_UP    = 2;
  PNG_FILTER_VALUE_AVG   = 3;
  PNG_FILTER_VALUE_PAETH = 4;

// Heuristic used for row filter selection.  These defines should NOT be
// changed.

  PNG_FILTER_HEURISTIC_DEFAULT    = 0;  // Currently "UNWEIGHTED"
  PNG_FILTER_HEURISTIC_UNWEIGHTED = 1;  // Used by libpng < 0.95
  PNG_FILTER_HEURISTIC_WEIGHTED   = 2;  // Experimental feature
  PNG_FILTER_HEURISTIC_LAST       = 3;  // Not a valid value

procedure png_build_grayscale_palette(bit_depth: int; palette: png_colorp);
             stdcall;
function png_check_sig(sig: png_bytep; num: int): int;
             stdcall;
procedure png_chunk_error(png_ptr: png_structp;
             const mess: png_charp);
             stdcall;
procedure png_chunk_warning(png_ptr: png_structp;
             const mess: png_charp);
             stdcall;
procedure png_convert_from_time_t(ptime: png_timep; ttime: time_t);
             stdcall;
function png_convert_to_rfc1123(png_ptr: png_structp; ptime: png_timep):
             png_charp;
             stdcall;
function png_create_info_struct(png_ptr: png_structp): png_infop;
             stdcall;
function png_create_read_struct(user_png_ver: png_charp;
             error_ptr: user_error_ptr; error_fn: png_error_ptr;