Variable rate embedded ADPCM coding scheme for packet speech on ATM networks

Author

Kondo, Kazuhiro ; Ohno, Masashi

Author_Institution

Hitachi Ltd., Tokyo, Japan

fYear

1990

fDate

2-5 Dec 1990

Firstpage

523

Abstract

A variable bit rate embedded ADPCM (adaptive differential PCM) coding scheme for packet speech, primarily for use in advanced private networks integrating ATM (asynchronous transfer mode) technology, is presented. The goal is to maintain high-quality speech even with the high percentage of information loss, anticipated in these networks. By varying the number of code bits of an embedded ADPCM coder from 6 bits per sample (48-kbits) for blocks of speech with high prediction gain, to 2 bits (16-kbits) for silent blocks, a good compromise between coding bit rate and speech quality with graceful degradation due to information loss was achieved

Keywords

encoding; packet switching; pulse-code modulation; speech analysis and processing; 16 kbit/s; 32 kbit/s; 48 kbit/s; ATM networks; adaptive differential PCM; advanced private networks; asynchronous transfer mode; code bits; coding bit rate; embedded ADPCM coding; graceful degradation; high prediction gain; high-quality speech; information loss; packet speech; packet switching; pulse code modulation; silent blocks; speech coding; variable bit rate; Asynchronous transfer mode; Bit rate; Degradation; Delay; Interpolation; Laboratories; Signal design; Speech coding; Standardization; System testing;

fLanguage

English

Publisher

ieee

Conference_Titel

Global Telecommunications Conference, 1990, and Exhibition. 'Communications: Connecting the Future', GLOBECOM '90., IEEE

Conference_Location

San Diego, CA

Print_ISBN

0-87942-632-2

Type

conf

DOI

10.1109/GLOCOM.1990.116566

Filename

116566