Vector quantization (VQ)-based motion field refinement technique for image sequence coding
Iole Moccagatta, Markus Schuetz, F. Moscheni, Fréderic Dufaux · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1995
To reduce temporal redundancies appearing in video sequences block based motion estimation techniques have been successfully applied. However, due to the block-based model blocking artifacts appear in the resulting displaced frame difference reducing the global coding scheme efficiency. In this paper, a motion field refinement technique is proposed to overcome these artifacts. The method is based on segmentation and vector quantization (VQ). The motion field resulting from the block-based motion estimation is segmented using a set of patterns stored in a codebook. These patterns are derived by the LBG algorithm trained on natural edges. The VQ technique allows a low cost data transmission of the segmentation information. Finally, the segmentation is controlled by an entropy criterion, which performs an optimal bit allocation between motion, segmentation, and DFD information. Simulation results show that a significant improvement is achieved using the proposed method. In particular moving edges are much better motion compensated and the visual quality is greatly enhanced.