Omnidirectional Stereo Vision

This paper discusses several interesting configurations of omnidirectional stereo (omnistereo) binocular omnistereo, N-ocular omnistereo, circular projection omnistereo and dynamic omni-stereo. An omnidirectional image can be either obtained by an omnidirectional camera or generated by image mosaicing. Usually an omnidirectional image has a 360-degree view around a viewpoint, and in its most common form, can be presented in a cylindrical surface around the viewpoint. This paper shows that an omnidirectional image for stereo vision can either have a single viewpoint or multiple viewpoints, and can be either viewer-centered or object-centered. With these generalizations, omnidirectional stereo vision can be extended from a viewer-centered binocular/ N-ocular omnistereo with a few fixed viewpoints to more interesting omnistereo configurations – circular projection omnistereo with many viewpoints in a small region, dynamic omnistereo with a few reconfigurable viewpoints in a large region, and object-centered omnistereo with many viewpoints distributed in a large region. Important issues on omnidirectional stereo imaging, epipolar geometry, and depth accuracy are discussed and compared.