Algorithms for intervector dependency utilization in variable-rate tree-structured vector quantization

In this paper we improve and extend our previous results in finite-state variable rate tree- structured vector quantization (FSVRTSVQ) by developing two new algorithms to increase its coding efficiency. The two new algorithms are derived to utilize the inter-codeword dependency and the tree structure property of the codebook so as to achieve bit rate reduction. The evaluation of both algorithms on various synthesis and real sources has shown that as many as 32.2% of bit rate savings has been obtained over the pruned tree-structured vector quantization (PTSVQ).