A fully adaptive DCT based color image sequence coder

摘要

A new fully adaptive discrete cosine transform (DCT) based color image sequence coding system is presented. A variable size block matching motion-compensation scheme is first designed. It differs from the conventional block matching motion compensation by varying the block size to make a better trade-off between the required bit rate and picture quality. Connected to the compensation scheme is the DCT with block size varied adaptively to the working block size derived from the motion compensator. Different gating functions are defined on the DCT to select the most efficient DCT coefficients in order to reach the best performance. An adaptive Laplacian quantizer and a two-sided Huffman entropy coder are finally utilized to get the optimal coding result.