darktable is an open source photography workflow application
A fast image processing library with low memory needs
A collection of packages providing extra functionality for GNU Octave
Lynkeos is an astronomical webcam image processing software for OS X.
ProStack - a platform for image processing and analysis
Collection GIMP plugins by zvezdochiot
Tools to access streams in PDF-files at the object level.
Easy converting pgm and ppm to (MASK+FG+BG)-djvu.
Libraries and command line tools for medical image processing.
Graphic Live Mixer
Digital image processing programs for Windows and Linux systems.
Some image processing tools
A small C library for building user interfaces with C, XML and CSS.
Tools to train Image Operators automatically from a set of samples.
Advanced image processing toolbox for Scilab on Unix/Linux/Mac OS
Astronomical object/structure detection from 1D and 2D data sets.
Bildster is an image processing library for educational purposes.
A Library for Interactive Modelling and Visualisation
Software for data analysis, image processing, simulations, solver.