A new segmentation algorithm for videophone applications based on stereo image pairs

The stereo image pair of a speaking person in front of a stationary background taken by two CCD-cameras is used as an input scene for a new segmentation algorithm. The algorithm is based on the phase correlation technique which provides a disparity vector field. A brightness adjustment procedure is performed to provide stereo image pairs suited for the segmentation procedure. Then, a coarse segmentation into background and speaking person is made to achieve a reliable segmentation result. Finally, finer segmentation using a coarse-to-fine control strategy is performed only at the object boundaries. An application is demonstrated by applying a lowpass filter selectively to the background of input sequences for low bit rate image coding algorithms