G\\\'MIC is an open and full-featured framework for image processing in Gimp.
You have several different user interfaces included in G\\\'MIC that will convert/manipulate/filter/visualize generic image datasets, from 1d scalar signals to 3d+t sequences of multi-spectral volumetric images.
A portable and thread-safe C++ library \\\'libgmic\\\' for generic image processing, embeddable in third-party applications. A command line interface \\\'gmic\\\' to perform image processing operations from a shell. An easy-to-use plug-in \\\'gmic_gimp\\\' which adds hundred of new filters to GIMP A web-service \\\'G\\\'MIC Online\\\', to apply image fiters directly on a web-browser. A Qt-based interface \\\'Zart\\\' for real-time manipulation of webcam images. A complete script language to develop your own complex image processing pipelines.