Multimode coding: application to CELP

Author

Taniguchi, Tomohiko ; Unagami, Shigeyuki ; Gray, Robert M.

Author_Institution

Fujitsu Lab. Ltd., Kawasaki, Japan

fYear

1989

fDate

23-26 May 1989

Firstpage

156

Abstract

The authors introduce a novel approach to narrow- and medium-band speech coding that can dynamically balance the transmission rate between the excitation and the spectral parameters. The coding algorithm, called multimode coding, operates several coding blocks, each of which has a different bit assignment in parallel, and selects the optimum coding block frame by frame based on an evaluation of the reproduced speech quality. This coding algorithm is applied to 4.8 and 8.0 kb/s CELP coders, and 2.0-2.4 dB of SNRseg improvement is achieved over conventional CELP coders. The spectral distortion measure is added as an evaluation function, improving the subjective speech quality

Keywords

encoding; filtering and prediction theory; speech analysis and processing; 4.8 kbit/s; 8 kbit/s; CELP; code excited linear prediction; medium-band coding; multimode coding; narrow-band coding; spectral distortion measure; speech coding; speech quality; Bit rate; Codecs; Distortion measurement; Laboratories; Linear predictive coding; Signal processing; Signal processing algorithms; Speech analysis; Speech coding; Speech processing;

fLanguage

English

Publisher

ieee

Conference_Titel

Acoustics, Speech, and Signal Processing, 1989. ICASSP-89., 1989 International Conference on

Conference_Location

Glasgow

ISSN

1520-6149

Type

conf

DOI

10.1109/ICASSP.1989.266387

Filename

266387