Overview and performance of CCITT/ANSI embedded ADPCM algorithms

Author

Sherif, Mostafa Hashem ; Bowker, Duane O. ; Bertocci, Guido ; Orford, Bruce A. ; Mariano, Gonzalo A.

Author_Institution

AT&T Bell Lab., Holmdel, NJ, USA

Volume

41

Issue

2

fYear

1993

fDate

2/1/1993 12:00:00 AM

Firstpage

391

Lastpage

399

Abstract

Embedded adaptive differential pulse coded modulation (ADPCM) algorithms quantize the differences between the input signal and the estimated signal into core bits and enhancement bits. CCITT Recommendation G.727, which describes embedded ADPCM encoding algorithms with 5, 4, 3, and 2 core bits, is virtually identical to the corresponding ANSI standard T1.310. The main features of G.727 and T1.310 and performance results are presented. A formal subjective evaluation of the speech performance of embedded ADPCM algorithms indicates that a midrise quantizer provides better voice transmission performance than its midtread counterpart when two core bits are used. The subjective data also show that the performance of the 40-kb/s midrise ADPCM algorithm with two feedback bits is indistinguishable from that of 64-kb/s pulse code modulation (PCM) for up to four tandem encodings. Embedded algorithms are therefore recommended for flexible congestion control of integrated traffic in multinode networks

Keywords

pulse-code modulation; speech coding; telecommunication standards; 40 kbit/s; ADPCM; ANSI standard T1.310; CCITT Recommendation G.727; adaptive differential pulse coded modulation; embedded algorithms; encoding; flexible congestion control; formal subjective evaluation; integrated traffic; midrise quantizer; multinode networks; speech performance; voice transmission performance; ANSI standards; Communication system traffic control; Decoding; Encoding; Feedback; Modulation coding; Phase change materials; Pulse modulation; Speech analysis; Transmitters;

fLanguage

English

Journal_Title

Communications, IEEE Transactions on

Publisher

ieee

ISSN

0090-6778

Type

jour

DOI

10.1109/26.216514

Filename

216514