OpenGL Mathematics (GLM)
ArrayFire, a general purpose GPU library
Swiss army knife of image processing
A collection of packages providing extra functionality for GNU Octave
itom - an Open Source Measurement, Automation and Evaluation Software
Astrophotography image & video processor. Full processing cycle
A Free Experimental System for Image Processing
Digital image processing programs for Windows and Linux systems.
A small C library for building user interfaces with C, XML and CSS.
Computer vision and image processing library for Qt.