Adaptive code excited predictive coding

Author

Galand, Claude R. ; Menez, Jean E. ; Rosso, Michele M.

Author_Institution

IBM Corp., La Gaude, France

Volume

40

Issue

6

fYear

1992

fDate

6/1/1992 12:00:00 AM

Firstpage

1317

Lastpage

1326

Abstract

A novel way to use the code excited linear prediction (CELP) concept that decreases the processing load while keeping the same speech quality is discussed. Rather than performing individual weighting of each candidate sequence, a global implementation of the perceptual weighting function at the codebook level is proposed. As a result, the analysis-by-synthesis procedure does not require the processing of all the candidate sequences through the synthesis and weighting filters; the complexity requirement of the algorithm is therefore much reduced. The concept is carried out with an adaptive codebook. Two fixed-point implementations of the adaptive CELP (ACELP) algorithm are reported: a 7.2 kb/s block coder (7 MIPS), and a 12 kb/s low-delay coder (11 MIPS). Both coders have been rated to provide the same quality as the 13 kb/s block coder adopted by the GSM for the European cellular telephone

Keywords

encoding; filtering and prediction theory; speech analysis and processing; 11 MIPS; 13 kbit/s; 7 MIPS; 7.2 kbit/s; adaptive CELP; adaptive code excited predictive coding; adaptive codebook; analysis-by-synthesis procedure; block coder; code excited linear prediction; codebook level; complexity requirement; fixed-point implementations; low-delay coder; perceptual weighting function; speech coding; Adaptive coding; Code standards; Costs; Filters; Predictive coding; Signal processing; Speech analysis; Speech coding; Technological innovation; Telephony;

fLanguage

English

Journal_Title

Signal Processing, IEEE Transactions on

Publisher

ieee

ISSN

1053-587X

Type

jour

DOI

10.1109/78.139238

Filename

139238