Background separation/filtering for videophone applications

To increase efficiency on interframe coding and/or to preserve speaker privacy for videophone applications, a method for real-time background separation based on stereoscopic range finding is developed. The algorithm includes foreground center extraction, foreground threshold calculation, occlusion-free direct block matching with quadtree block subdivision, and contour segmentation using a motion edge. The algorithm is evaluated using a stereo-video sequence. For an application using the background separation technique, background filtering is introduced. Background filtering can decrease the number of inessential coded blocks, when applied to a motion-compensated hybrid differential pulse-code modulation (DPCM)/transform coder. If the cut-off frequency for filtering characteristics is further lowered, the filtering will conceal details in the background.<<ETX>>

[1]  Hiroyuki Yamaguchi,et al.  Stereoscopic images disparity for predictive coding , 1989, International Conference on Acoustics, Speech, and Signal Processing,.

[2]  Y. Aloimonos,et al.  Visual shape computation , 1988, Proc. IEEE.

[3]  Takao Nishitani,et al.  A real-time video signal processor suitable for motion picture coding applications , 1989 .

[4]  Ray A. Jarvis,et al.  A Perspective on Range Finding Techniques for Computer Vision , 1983, IEEE Transactions on Pattern Analysis and Machine Intelligence.