A 6.4 kbit/s extension to the G.729 speech coder

Author

Kataoka, A. ; Kurihara, S. ; Hayashi, S.

Author_Institution

NTT Human Interface Labs., Tokyo, Japan

fYear

1997

fDate

7-10 Sep 1997

Firstpage

69

Lastpage

70

Abstract

This paper proposes a 6.4-kbit/s extension to the G.729 speech coder. Each G.729 module was investigated to determine which bits could be removed without hurting the speech quality, then a 6.4-kbit/s coder was designed. This coder has an 11-bit algebraic codebook that uses two or three pulses. We also propose a conditional orthogonalized search for the fixed codebook to improve the speech quality. The conditional orthogonalized search chooses one of two search methods (orthogonalized or non-orthogonalized) based on the optimum pitch gain. Subjective tests have indicated that the quality of the proposed coder is equivalent to that of the 6.3-kbit/s G.723.1 coder

Keywords

algebraic codes; code standards; modules; search problems; speech intelligibility; telecommunication standards; vocoders; 11 bit; 6.3 kbit/s; 6.4 kbit/s; G.723.1 coder; G.729 module; G.729 speech coder; ITU-T; algebraic codebook; conditional orthogonalized search; nonorthogonalized search; optimum pitch gain; speech quality; subjective tests; Bit rate; Cepstrum; Degradation; Humans; Prediction methods; Protection; Search methods; Speech; Testing;

fLanguage

English

Publisher

ieee

Conference_Titel

Speech Coding For Telecommunications Proceeding, 1997, 1997 IEEE Workshop on

Conference_Location

Pocono Manor, PA

Print_ISBN

0-7803-4073-6

Type

conf

DOI

10.1109/SCFT.1997.623900

Filename

623900