We have recently proposed a new approach for speech coding based on the use of the Discrete Wavelet Transform and Vector Quantization called the Discrete Wavelet Vector Transform Coding (DWVTC). This approach, although it provides results close to the optimal multiresolution codebook, suffers from the fixed size of the used codebook. In this paper, we propose a new scheme based on a multiresolution hierarchical codebook structure which gives better results.
Bibliographic reference. Mandridake, E. / Atay, R. / Najim, M. (1995): "Adaptive speech vector coding with a multiresolution hierarchical codebook", In EUROSPEECH-1995, 669-672.