Writing GIMP scripts
PAINTING BY NUMBERS
Many users turn to GIMP for pictures in the window, but some may not realize GIMP also has scripting capabilities that allow you to automate recurring tasks. The Python scripting language is a useful alternative to the GIMP’s integrated Lisp dialect.
The GIMP image manipulation program has a variety of useful functions. But navigating a complicated menu tree can be a pain if you need to apply the same tools to a large number of images. Fortunately, the GIMP has an integrated programming interface that allows users to script recurring tasks. This said, the Scheme  programming language is not everyone’s idea of fun; its bracket-oriented syntax is difficult to learn. Little surprise that fans of other scripting languages have come up with alternatives. The Perl interface, GIMP-Perl, is fairly advanced and supports a server mode in which GIMP parses scripts without needing to run the GUI.