Stereo Retinex

The retinex algorithm for lightness and color constancy is extended to include 3-dimensional spatial information reconstructed from a stereo image. A key aspect of traditional retinex is that, within each color channel, it makes local spatial comparisons of intensity. In particular, intensity ratios are computed between neighboring spatial locations, retinex assumes that a large ratio indicates a change in surface reflectance, not a change in incident illumination; however, this assumption is often violated in 3-dimensional scenes, where an abrupt change in surface orientation can lead to a significant change in illumination. In this paper, retinex is modified to use the 3-dimensional edge information derived from stereo images. The edge map is used so that spatial comparisons are only made between locations lying on approximately the same plane in 3-dimensions. Experiments on real images show this method works well, however, they also reveal that it can lead to isolated regions, whic...

• Type: Conference
• Year: 2006
• Where: CRV
• Authors: Weihua Xiong, Brian V. Funt
• Keywords: CRV 2006, Retinex, Retinex Algorithm, Robotics, Stereo Retinex