Closed-loop motion compensation for video coding standards

In the classical block-matching motion-estimation approach, the motion vectors which result in minimum distortion between the estimated and the actual image block are chosen. However, these motion vectors may not be optimal in terms of coding efficiency. An analysis by synthesis method which selects the optimal motion vectors, using the resulting bit rate and distortion, is presented. A significant reduction in bit rate is achieved with virtually no degradation in objective image quality. H.263 is used in simulation experiments to test the algorithm