CMVision is a real-time color classification and segmentation library which can track up to 256 colors in a 640x480 30fps video stream. The vision system core is a C++ library which is easily extensible for custom applications, and should compile on any *nix compatible environment. Also provided is a video capture library for Video4Linux II.
ImLib3D is a C++ library and visualization system for 3D (volumetric) image processing. It contains most basic image processing algorithms, as well as some more sophisticated ones. Its images are STL-compliant templated containers. It inculdes a viewer that features multiplanar views, interactive image processing, animations, vector field views, and 3D (OpenGL) multiplanar. Its main application is medical image processing.
Moron (Method for Object Recognition of Obscure Nature) is a tool to classify given images based on their content. Technically, it combines feature extraction and machine learning. The classes recognized depend on the version. A typical Moron version tries at least to separate drawn content from photographs (pron) and thus could be adapted as a spam filter for cartoon newsgroups.
SIP provides image processing, pattern recognition, and computer vision routines for SciLab, a Matlab-like matrix-oriented programming environment. SIP is able to read/write images in almost 90 major formats, including JPEG, PNG, BMP, GIF, FITS, and TIFF. It includes routines for filtering, segmentation, edge detection, morphology, curvature, fractal dimension, distance transforms, multiscale skeletons, and more.
The Pattern Recognition Application Programmer's Interface aims to be a fully-featured, easy-to-use general C++ framework for various pattern recognition tasks, especially image analysis. It features support for many image formats, well-known image analysis methods, classification and feature analysis tools, XML serialization, etc.