Main index API Topic index API Glossary

# ASImage Import

functionality for reading images from files

libAfterImage/import.h

- NAME

  import

  - Image file format autodetection, reading and decoding routines.

- SEE ALSO

      Functions :
              file2ASImage(), get_asimage(), file2pixmap()

      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/gamma

- NAME

  SCREEN_GAMMA

  - Defines default value for screen gamma correction.

- SOURCE

      #define SCREEN_GAMMA 2.2
      #define DEFAULT_PNG_IMAGE_GAMMA     0.45455

libAfterImage/ASImageFileTypes

- NAME

  ASImageFileTypes

  - List of known image file formats.

- SOURCE

      typedef enum
      {
          ASIT_Xpm = 0,
          ASIT_ZCompressedXpm,
          ASIT_GZCompressedXpm,
          ASIT_Png,
          ASIT_Jpeg,
          ASIT_Xcf,
          ASIT_Ppm,
          ASIT_Pnm,
          ASIT_Bmp,
          ASIT_Ico,
          ASIT_Cur,
          ASIT_Gif,
          ASIT_Tiff,
          ASIT_XMLScript,
          /* reserved for future implementation : */
          ASIT_Xbm,
          ASIT_Targa,
          ASIT_Supported = ASIT_Targa,
          ASIT_Pcx,
          ASIT_HTML,
          ASIT_XML,
          ASIT_Unknown
      }ASImageFileTypes;

libAfterImage/ASImageListEntry

- NAME

  ASImageListEntry

  - entry in linked list of images loaded from single directory.

- SOURCE

      typedef struct ASImageListEntry
      {
      #define MAGIC_ASIMAGE_LIST_ENTRY            0xA3A311E4
      #define IS_ASIMAGE_LIST_ENTRY(e)  (((e)!=NULL)&&((e)->magic==MAGIC_ASIMAGE_LIST_ENTRY)&&((e)->ref_count>0))

          unsigned long magic ;
          struct ASImageListEntry *prev, *next ;
          char   *name ;
          char   *fullfilename ;

          ASImageFileTypes    type;
          ASImage            *preview;

          int ref_count;
      }ASImageListEntry;

libAfterImage/import/file2ASImage()

- NAME

  file2ASImage()

  - load ASImage from file.

- SYNOPSIS

      ASImage *file2ASImage( const char *file, ASFlagType what,
                             double gamma,
                             unsigned int compression, ... );

- INPUTS

  file
    - file name with or without directory name
  what
    - reserved for future use
  gamma
    - gamma value to be used to correct image
  compression
    - compression level of the resulting ASImage
  ...
    - NULL terminated list of strings, representing arbitrary number of directories to be searched each.

- RETURN VALUE

      Pointer to ASImage structure holding image data on success.
      NULL on failure

- DESCRIPTION

      file2ASImage will attempt to interpret filename in the following way:
      1)It will try to find file using unmodified filename in all the
      provided search paths.
      2)It will attempt to append .gz and then .Z to the filename and
      find such file in all the provided search paths.
      3)If filename ends with extension consisting of digits only - it will
      attempt to find file with this extension stripped off. On success
      this extension will be used to load subimage from the file with that
      number. Subimages are supported only for XCF, GIF, BMP, ICO and CUR
      files.
      After the file is found file2ASImage() attempts to detect file format,
      and if it is known it will load it into new ASImage structure.

- EXAMPLE

      asview.c: ASView.2

libAfterImage/import/get_asimage()

- NAME

  get_asimage()

  - increment reference counter if file is already loaded, or load image from file.

- SYNOPSIS

      ASImage *get_asimage( ASImageManager* imageman, const char *file,
                            ASFlagType what, unsigned int compression );

- INPUTS

  imageman
    - pointer to valid ASVisual structure.
  file
    - root window ID for the destination screen.
  what
    - full image file's name with path.
  compression
    -

- RETURN VALUE

      Pointer to ASImage structure holding image data on success.
      NULL on failure

- DESCRIPTION

      get_asimage will attempt check with the ASImageManager's list of load
      images, and if image with requested filename already exists - it will
      increment its reference count and return its pointer.
      Otherwise it will call file2ASImage() to load image from file. It will
      use PATH and gamma values from the ASImageManager to pass to
      file2ASImage(). If image is successfully loaded - it will be added to
      the ASImageManager's list and its pointer will be returned.

- SEE ALSO

      file2ASImage()

libAfterImage/import/file2pixmap()

- NAME

  file2pixmap()

  - convinience function to load file into X Pixmap.

- SYNOPSIS

      Pixmap file2pixmap( struct ASVisual *asv, Window root,
                          const char *realfilename,
                          Pixmap *mask_out);

- INPUTS

  asv
    - pointer to valid ASVisual structure.
  root
    - root window ID for the destination screen.
  realfilename
    - full image file's name with path.

- RETURN VALUE

      Pixmap ID of the X Pixmap filled with loaded image. If mask_out is
      not NULL it will point to image mask Pixmap ID if there is an alpha
      channel in image, None otherwise.
      On failure None will be returned.

- DESCRIPTION

      file2pixmap() will attempt to open specified file and autodetect its
      format. If format is known it will load it into ASImage first, and
      then convert it into X Pixmap. In case image has alpha channel -
      mask Pixmap will be produced if mask_out is not NULL.

Topic index Glossary Back to Top

AfterStep version 2.1.2