An improved 2.4 kbps class-dependent CELP speech coder

Author

Jiang, Yingbo ; Cuperman, Vladimir

Author_Institution

Sch. of Eng. Sci., Simon Fraser Univ., Burnaby, BC, Canada

Volume

3

fYear

1995

fDate

18-22 Jun 1995

Firstpage

1414

Abstract

This paper presents an improved 2.4 kbps class-dependent CELP speech coder. The improved coder is based on our previous efforts on a 2.4 kbps CELP coder. New classification schemes in both open-loop and closed-loop are used. An extra transition class is used in the closed-loop classification. We developed a predictive LSP VQ to reduce LPC bit rate to as low as 18 bits/frame (30 ms) while maintaining low spectral distortion. Experimental results show that the quality of synthesized speech is improved. We also discuss the results obtained from class-dependent weighting filters, and a class-dependent postfilter

Keywords

filtering theory; linear predictive coding; speech coding; speech intelligibility; speech synthesis; vector quantisation; vocoders; 2.4 kbit/s; 30 ms; LPC bit rate reduction; class-dependent CELP speech coder; class-dependent postfilter; class-dependent weighting filters; classification schemes; closed-loop classification; experimental results; low spectral distortion; open-loop; predictive LSP VQ; synthesized speech quality; Autocorrelation; Bit rate; Filters; Linear predictive coding; Mobile communication; Speech analysis; Speech coding; Speech synthesis; Stochastic processes; Vectors;

fLanguage

English

Publisher

ieee

Conference_Titel

Communications, 1995. ICC '95 Seattle, 'Gateway to Globalization', 1995 IEEE International Conference on

Conference_Location

Seattle, WA

Print_ISBN

0-7803-2486-2

Type

conf

DOI

10.1109/ICC.1995.524436

Filename

524436