GIMP has a feature to extend capabilities by writing scripts to manipulate images. These scripts can be script-fu or python-fu. This is basically equivalent to Photoshop’s actions. For script-fu, it is written in an implementation of Scheme called SIOD, a kind of functional language similar to LISP (So you will face a lot of parentheses, just like LISP .. :P). You can call almost, if not all, functions available in GIMP, i.e., every menus, commands, extensions, python-fu, and script-fu. This means that what your script-fu will become a function in GIMP automatically. Nice, isn’t it ? These are script-fu I wrote:
| SCRIPTS | DESCRIPTION |
|---|---|
| kitty.in.th-auto-levels.scm | Scale level to the full range. The cut-off threshold is configurable |
| kitty.in.th-auto-photo-frame.scm | My auto-level + photo-frame |
| kitty.in.th-bw.scm | Convert an image to grayscale. A color filter is selectable |
| kitty.in.th-contrast-mask.scm | Perform contrast mask |
| kitty.in.th-handheld-size.scm | Resize image to handheld resolutions |
| kitty.in.th-ir.scm | Infrared Filter effect |
| kitty.in.th-lomo.scm | Lomography effect |
| kitty.in.th-photo-frame.scm | My custom photo frame |
| kitty.in.th-sepia.scm | Sepia effect |
| kitty.in.th-soft-filter.scm | Soft filter effect |
| kitty.in.th-velvia.scm | Velvia-like effect |
Just put these scripts to ~/.gimp-2.x/scripts/. They should appear in your Image’s Script-Fu -> kitty.in.th automatically.
Please be noted that most image manipulation techniques used in these scripts were taken from somewhere else (e.g., gimp guru, pantip.com, thaidphoto, etc. etc..). I just wrote script-fu to automate them. Credits should be given to those who invent the techniques.