merging imread and imwrite

[John W. Eaton]

I'd like to get imread and imwrite functions in Octave.  I see that
there are functions in Octave Forge, but they will need some work.

The core of imread is

    ## divert jpegs and pngs to "jpgread" and "pngread"
    if ( file_in_loadpath("jpgread.oct") &&
      (strcmp(ext, ".JPG") || strcmp(ext, ".JPEG")) )
      varargout{1} = jpgread(fn);
      break
    endif
    if ( file_in_loadpath("pngread.oct") && (strcmp(ext, ".PNG")) )
      varargout{1} = pngread(fn);
      break
    endif
    
    ## alternately, use imagemagick
    if ( file_in_loadpath("__magick_read__.oct") )
      [varargout{1:nargout}] = __magick_read__(fn, varargin{:});
      break
    endif

Why not use ImageMagick to do all the work instead of special-casing
jpg and png files?

Also, is there some other graphics library that we could wrap to
handle reading and writing image files that might be better, or is
ImageMagick a good choice?

I see that the Matlab docs claim the following formats are handled:

  imead  imwrite
  -----  -------
   bmp     bmp
           cur
   gif     gif
   hdf     hdf
           ico
   jpg     jpg
   pbm     pbm
   pcx     pcx
   pgm     pgm
   png     png
   pnm
   ppm     ppm
   ras     ras
   tif     tif
   xwd     xwd


Comments?

jwe