The Augmented Reality Tool Kit (ARToolKit) captures images from video sources, optically tracks markers in the images, and composites them with computer-generated content using OpenGL. Dual-licensed, under the GPL, plus commercially by ARToolworks, Inc.
NEW: A free demonstration of ARToolKit capabilities has been made available as part of ARToolworks "Codex Interactivus: Bringing Leonardo to Life!" Kickstarter project. Download from https://www.kickstarter.com/projects/artoolworks/codex-interactivus-bringing-leonardo-to-life/
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