Generalized-cost-measure-based address-predictive vector quantization
Address-predictive vector quantization (APVQ) exploits the interblock dependency by jointly encoding the addresses of the codewords associated with spatially close blocks. It profiles the same image quality as memoryless VQ for a much lesser bit rate (BR) and the same computational complexity. In the generalized-cost-measure-based APVQ, the two steps of the encoding process, namely, VQ and predictive address encoding, are carried out jointly by minimizing a generalized cost measure, which takes into account both the BR and the distortion. Computer simulations show that a significant improvement can be obtained with respect to APVQ in terms of both BR and distortion. Compared with memoryless VQ, a bit-rate reduction of almost 60% is obtained for the same image quality.