Speech Recognition with Hierarchical Codebook Search

3 1 Specifications 4 1.1 Problem Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.2 The Decimation Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.3 Goal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2 Preconditions 6 2.1 Distortion and Distance Measurement . . . . . . . . . . . . . . . . . . . . . . 6 2.2 Random Generated Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.3 Number of Initial Codebook Vectors . . . . . . . . . . . . . . . . . . . . . . . 7 3 Solution Process 7 4 Program Description 8 4.1 Training, Test and Codebook Vector Generation . . . . . . . . . . . . . . . . . 8 4.2 Hierarchical Codebook Generation with Decimation . . . . . . . . . . . . . . . 9 4.3 Hierarchical Codebook Generation with LBG . . . . . . . . . . . . . . . . . . 11 4.4 Test and Quantization Programs . . . . . . . . . . . . . . . . . . . . . . . . . 11 5 Evaluation 11 5.1 General Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 5.1.1 Equality of a Vector Quantization with a Full and a Hierarchical Codebook 12 5.1.2 Degenerated Trees . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 5.2 Evaluation for Different Values of Parameter ft . . . . . . . . . . . . . . . . . 16 5.3 Evaluation for Different Values of Parameter B . . . . . . . . . . . . . . . . . 18 5.4 Application to a Speech Recognition Task . . . . . . . . . . . . . . . . . . . . 21