Abstract: In this paper, we present a novel coding technique which makes use of the nonstationary characteristics of an image sequence displacement field to estimate and encode motion information. In addition, we develop a wavelet transform approach using cross-scale vector quantization to encode single frames during periods of high motion and scene changes. The objective of this design is to demonstrate the coding potential of a newly developed motion estimator called the Compound Linearized MAP (CLMAP) estimator. This estimator can be used as a means for producing motion vectors which may be regenerated at the decoder with a coarsely quantized error term created in the encoder. The motion estimator generates highly accurate motion estimates. This permits the elimination of a separately coded displaced frame difference (DFD) and coded motion vectors. We exploit both the advantages of the nonstationary motion estimator and the edge preserving quality of the wavelet based still frame coder to improve the visual quality of reconstructed video-conferencing image sequences, at low bit rates.!20
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