Decision trees for vector quantizer codebook searching
Several incremental algorithms are presented for designing fixed length decision trees for searching the codebook of a vector quantizer (VQ). These trees are then used as the basis for a two-stage VQ, wherein the first stage is a high-rate, structured VQ with a fast quantization algorithm and the second stage is a low-rate optimal VQ. The mean square error and complexity of the resulting two-stage VQs are presented for i.i.d. Gaussian and speech sources, and are compared with both TSVQ and previous tree based two-stage VQ designs.<<ETX>>