Efficient two-stage vector quantization speech coder using wavelet coefficients of excitation signals

Acoustical Science and Technology

Erinnoviar¹  Seiji Hayashi¹  Masahiro Suguimoto¹ 

[1] Department of Electronics and Computer Systems, Takushoku University

关键词: Speech processing;    Wavelet;    Vector quantization;   

DOI  :  10.1250/ast.26.43

学科分类：声学和超声波

来源: Acoustical Society of Japan

【 摘 要 】

References(13)An improved backward prediction coder featuring two-stage vector quantization (VQ) of shape codevectors is presented. Efficient two-stage VQ is achieved using the wavelet coefficients of excitation signals; i.e., wavelet coefficients are calculated by applying a discrete wavelet transform to excitation signals, and the results are divided into an approximation group and a detail group. The data lengths of both approximation and detail coefficients are half that of conventional two-stage VQ systems. Simulation results show that the proposed coder achieves a better weighted signal-to-noise ratio (WSNR) than conventional coders and, in terms of reconstructed speech quality, ranks between the FS-1016 Code Excited Linear Prediction (CELP) coder and the Vector Sum Excited Linear Predictive Coding (VSELP) coder.

【 授权许可】

Unknown