A method, for use in a segmentation-based coding system, for detecting motion vectors between a current frame and a previous frame of digital video signal comprises the steps of (a) generating segmentation data for each of the segmented regions, the segmentation data including contour information...http://www.google.com/patents/US5686973?utm_source=gb-gplus-sharePatent US5686973 - Method for detecting motion vectors for use in a segmentation-based coding system 
