Image coding using variable-rate side-match finite-state vector quantization

In the future, B-ISDN (Broad-band Integrated Services Digital Network) users can send various kinds of information, such as voice, data, and image, over the same network and send information only when necessary. It has been recognized that variable-rate encoding techniques are more suitable than fixed-rate techniques for encoding images in a B-ISDN environment. This paper describes a new variable-rate side-match finite-state vector quantization with a block classifier (CSMVQ) algorithm. In an ordinary fixed-rate SMVQ, the size of the state codebook is fixed. In our CSMVQ algorithm, the size of the state codebook is changed according to the characteristics of the current vector which can be predicted by a block classifier. In our experiments, the improvement over SMVQ is up to 1.761 dB at a lower bit rate. Moreover, the improvement over VQ can be up to 3 dB at nearly the same bit rate.