Swiss army knife of image processing
Emgu CV is a cross platform .Net wrapper for OpenCV
itom - an Open Source Measurement, Automation and Evaluation Software
Scientific Visualisation Made Easy
ProStack - a platform for image processing and analysis
A Free Experimental System for Image Processing
Libraries and command line tools for medical image processing.
Digital image processing programs for Windows and Linux systems.
Tools to train Image Operators automatically from a set of samples.
Advanced image processing toolbox for Scilab on Unix/Linux/Mac OS
Graphical Interface for Medical Image Analysis and Simulation
OTB is an open-source C++ library for remote sensing images processing
Astronomical object/structure detection from 1D and 2D data sets.
OpenGL Image Processing LIBrary
Bildster is an image processing library for educational purposes.