jpeg.inc

著名的游戏开发库Allegro4.2.0 for DELPHI

{******************************************************************/
/*                  libjpeg for Allegro                           */
/*                  by Eric Vannier                               */
/*                                                                */
/*                  libpng for Allegro                            */
/*                  by Saniko                                     */
/*                                                                */
/*    Version : 1.03                                              */
/*    Date    : 02/03/98                                          */
/*                                                                */
/*   If you need some information read the readme.1st             */
/*                                                                */
/******************************************************************}
{$IFDEF ALLEGRO_INTERFACE}
const
  JPEG_VERSION    = 1;
  JPEG_SUBVERSION = 0;
  JPEG_REVISION   = 3;
  JPEG_DESC       = 'jpeg library v1.03 based on IJG v6.0a';
  JPEG_AUTHOR     = 'Eric Vannier as known as Fweibuli';
  DEFAULT_QUALITY = 75;

type
  color_type_t = (CT_RGB, CT_GRAYSCALE);
  decoding_speed_t = (DS_SLOW, DS_FAST);

  p_jpeg_code_param = ^jpeg_code_param;
  jpeg_code_param = record
    {* quality factor : from 0 to 100. Lowest value result in a poor quality/good compression image *}
    quality       : sint32;
    {* type of output : color or grayscale output. The input should be always RGB encoded with
       Grayscale Y value used *}
    color_type    : color_type_t;
  end;

  p_jpeg_decode_param = ^jpeg_decode_param;
  jpeg_decode_param = record
    {* type of the result : color or grayscale output. this will be always RGB coded *}
    color_type      : color_type_t;
    {* scale factor of the output. It must be 1 , 2, 4 ,8. 1 is default.
       The main interest is to have thumbnail images and therefore fast decompression *}
    scale_factor    : sint32;
    {* Unless you want to save for thumbnail output for example, this should be DS_SLOW,
        since a fast output may result in a lower quality *}
    decoding_speed  : decoding_speed_t;
    {* first color to be altered in the palette. Only used in 8 bits mode.
       It is faster if it equals zero. *}
    first_color     : uint32;
    {* Number of colors to be altered in the palette. Only used in 8 bits mode.
       This should be used with the previous option.
       first_color+nbr_colors must be less than 256 *}
    nbr_colors      : uint32;
  end;

var
  load_jpeg: function(const filename: PChar; pal: P_PALETTE): P_BITMAP; cdecl;
  save_jpeg: function(const filename: PChar; bmp: P_BITMAP; const pal: P_PALETTE): sint32; cdecl;

  load_jpeg_ex: function(const filename: PChar; pal: P_PALETTE; const jpeg: p_jpeg_decode_param): P_BITMAP; cdecl;
  save_jpeg_ex: function(const filename: PChar; bmp: P_BITMAP; const pal: P_PALETTE; const jpeg: p_jpeg_code_param): sint32; cdecl;

  load_png: function(const filename: PChar; pal: P_PALETTE): P_BITMAP; cdecl;
  save_png: function(const filename: PChar; bmp: P_BITMAP; const pal: P_PALETTE): sint32; cdecl;
{$ENDIF ALLEGRO_INTERFACE}
{$IFDEF ALLEGRO_IMPLEMENTATION}
{$ENDIF ALLEGRO_IMPLEMENTATION}
{$IFDEF ALLEGRO_LOADVARIABLE}
  load_jpeg                 := LoadDLL('load_jpeg');
  save_jpeg                 := LoadDLL('save_jpeg');
  load_jpeg_ex              := LoadDLL('load_jpeg_ex');
  save_jpeg_ex              := LoadDLL('save_jpeg_ex');
  load_png                  := LoadDLL('load_png');
  save_png                  := LoadDLL('save_png');
{$ENDIF ALLEGRO_LOADVARIABLE}