ImageJ

ImageJ can display, edit, analyze, process, save, and print 8-bit color and grayscale, 16-bit integer, and 32-bit floating point images. It can read many image file formats, including TIFF, PNG, GIF, ...
Language(s): Java
Operating system(s): Cross-platform
License: Public domain

Insight Segmentation and Registration Toolkit

ITK is an open-source, cross-platform system that provides developers with an extensive suite of software tools for image analysis. Developed through extreme programming methodologies, ITK employs le...
Language(s): C, C++, Fortran, Python
Operating system(s): Cross-platform
License: Apache 2.0

VTK

The Visualization Toolkit (VTK) is an open-source, freely available software system for 3D computer graphics, image processing, and visualization. It consists of a C++ class library and several interp...
Language(s): C, C++, Python
Operating system(s): Cross-platform
License: 3-Clause BSD License