export.3x

Langue: en

Autres versions - même langue

Version: AfterStep v.2.2.8 (debian - 07/07/09)

Section: 3 (Bibliothèques de fonctions)

Sommaire

NAME

export - functionality for writing images into files libAfterImage/export.h

NAMEexport

- Image output into different file formats.

SEE ALSO

 Structures :
          ASXpmExportParams
          ASPngExportParams
          ASJpegExportParams
          ASGifExportParams
          ASImageExportParams
 
 Functions :
         ASImage2file()
 
 Other libAfterImage modules :
          ascmap.h asfont.h asimage.h asvisual.h blender.h export.h
          import.h transform.h ximage.h

AUTHOR

 Sasha Vasko <sasha at aftercode dot net>
libAfterImage/ExportFlags

NAMEEXPORT_GRAYSCALE

- save image as grayscale. EXPORT_ALPHA - save alpha channel if format permits EXPORT_APPEND - if format allows multiple images - image will be appended

FUNCTION

 Some common flags that could be used while writing images into
 different file formats.

SOURCE

 #define EXPORT_GRAYSCALE            (0x01<<0)
 #define EXPORT_ALPHA                (0x01<<1)
 #define EXPORT_APPEND               (0x01<<3)  /* adds subimage  */
 #define EXPORT_ANIMATION_REPEATS    (0x01<<4)  /* number of loops to repeat GIF animation */
 /*****/

libAfterImage/ASPngExportParams

NAMEASPngExportParams

- parameters for export into PNG file.

SOURCE

 typedef struct
 {
     ASImageFileTypes type;
     ASFlagType flags ;
     int compression ;
 }ASPngExportParams ;

libAfterImage/ASJpegExportParams

NAMEASJpegExportParams

- parameters for export into JPEG file.

SOURCE

 typedef struct
 {
     ASImageFileTypes type;
     ASFlagType flags ;
     int quality ;
 }ASJpegExportParams ;

libAfterImage/ASGifExportParams

NAMEASGifExportParams

- parameters for export into GIF file.

SOURCE

 typedef struct
 {
     ASImageFileTypes type;
     ASFlagType flags ;
     int dither ;
     int opaque_threshold ;
     unsigned short animate_delay ;
     unsigned short animate_repeats ;
 }ASGifExportParams ;

libAfterImage/ASTiffExportParams

NAMEASTiffExportParams

- parameters for export into TIFF file.

SOURCE

 typedef struct
 {
     ASImageFileTypes type;
     ASFlagType flags ;
     CARD32 rows_per_strip ;
 
 /* these are suitable compressions : */
 #define TIFF_COMPRESSION_NONE       1
 #define TIFF_COMPRESSION_OJPEG      6   /* !6.0 JPEG */
 #define TIFF_COMPRESSION_JPEG       7
 #define TIFF_COMPRESSION_PACKBITS   32773   /* Macintosh RLE */
 #define TIFF_COMPRESSION_DEFLATE    32946   /* Deflate compression */
     /* you should be able to use other values from tiff.h as well */
     CARD32 compression_type ;
     int jpeg_quality ;
 
     int opaque_threshold ;
 }ASTiffExportParams ;

libAfterImage/ASImageExportParams

NAMEASImageExportParams

- union of structures holding parameters for export into different file formats.

DESCRIPTION

 Treatment of this union depends on what type of export was requested.

SEE ALSO

 ASImageFileTypes

SOURCE

 typedef union ASImageExportParams
 {
     ASImageFileTypes   type;
     ASXpmExportParams  xpm;
     ASPngExportParams  png;
     ASJpegExportParams jpeg;
     ASGifExportParams  gif;
     ASTiffExportParams tiff;
 }ASImageExportParams;

libAfterImage/export/ASImage2file()

NAMEASImage2file()

SYNOPSIS

 Bool ASImage2file( ASImage *im, const char *dir, const char *file,
               ASImageFileTypes type, ASImageExportParams *params );

INPUTS

im
- Image to write out.
dir
- directory name to write file into (optional, could be NULL)
file
- file name with or without directory name.
type
- output file format. ( see ASImageFileTypes )
params
- pointer to ASImageExportParams union's member for the above type, with additional export parameters, such as quality, compression, etc. If NULL then all defaults will be used.

RETURN VALUE

 True on success. False - failure.

DESCRIPTION

 ASImage2file will construct filename out of dir and file components
 and then will call specific filter to write out file in requested
 format.

NOTES

 Some formats support compression, others support lossy compression,
 yet others allows you to limit number of colors and colordepth.
 Each specific filter will try to interpret those parameters in its
 own way.

EXAMPLE

 asmerge.c: ASMerge.3