Program, apparatus, and method for quantization using hierarchical codebook based on probability model

摘要

PROBLEM TO BE SOLVED: To provide a program, a device, and a method for creating a codebook with a small quantization error while minimizing memory usage to achieve data quantization.SOLUTION: There are provided: primary codebook creation means for classifying a set X of training vectors into a K1-number of primary cluster groups and then creating a primary codebook including a K1-number of representative vectors S; probability model generation means for assigning each representative vector Swith the set X of the training vectors x by using the primary codebook and then generating, for each representative vector (Sof S), a probability model from a set of residual vectors (=x-S) obtained between the representative vector Sand the training vectors x; and secondary codebook creation means for classifying a K1-number of probability models into an M-number of secondary cluster groups, then creating, for each secondary cluster, a secondary codebook Tfrom a set of residual vectors based on the assigned representative vector S, and creating a total of M-number of secondary codebooks T-T.SELECTED DRAWING: Figure 1