Edge-based motion estimation and region-based contour tracing for very low bit rate video coding

Abstract

A new algorithm for image sequence coding with a very low bit rate and high picture quality is proposed. The proposed cod- ing system is composed of interframe and intraframe coding. In the interframe coding, an edge-based motion estimation algorithm is used to find the motion vector of a moving block instead of using the conventional block-matching algorithm. The edge-based method re- duces the entropy of the estimated motion vectors within a frame. Since the motion vectors are usually encoded by entropy coding, bit rate is also reduced. In the intraframe coding, a region-based algo- rithm is used to trace the contour of an object and estimate its pa- rameters from a predetermined database of various geometric shapes. It can reduce the blocking effect. By testing several image sequences such as ''Miss America'' and ''Claire'' with 10 frames/s in quarter common intermediate format (QCIF) the proposed coding system has about 1 to 2 dBs higher peak SNRs than the H.263 system. © 1998 SPIE and IS&T. (S1017-9909(98)01401-9)