Just today I was looking at this little Gimp-Perl plug-in I wrote, so that I could instantly save my .XCF gimp working files as .png with a single hotkey.

It's a very basic example, I guess to apply it to your problem you'd want to call the plug-in-color-map function (found in the DB Browser), uncomment the undo group bits and so on. Then just stick it in /usr/lib/gimp/2.0/plug-ins (or wherever your plug-ins directory is).

As others have pointed out, ImageMagick is normally the way to go for this sort of thing. But of course, gimp offers a much richer image manipulation toolkit, so mastering the gimp is a worthwhile goal.

use Gimp;
use Gimp::Fu;

#Gimp::set_trace(TRACE_ALL);

register "pngify",
         "Save this image as a PNG",
         "Save this image as a PNG, so that you don't have to go throu
+gh million
s of dialogs.",
         "Sam Vilain",
         "Sam Vilain",
         "1.0",
         N_"<Image>/File/Save as PNG",
         "RGB*, GRAY*",
         [ ],
         sub {

   my($img,$drawable)=@_;

   my $fn = $img->get_filename;
   $img = $img->duplicate;

   #eval { $img->undo_group_start };

   $drawable = $img->flatten;

   $fn =~ s{\.\w+}{.png} or die;
   $img->file_png_save_defaults($drawable, $fn, $fn);

   #eval { $img->undo_group_end };

   undef;
};

exit main;
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$h=$ENV{HOME};my@q=split/\n\n/,`cat $h/.quotes`;$s="$h/."
."signature";$t=`cat $s`;print$t,"\n",$q[rand($#q)],"\n";
[download]