A wideband speech and audio codec at 16/24/32 kbit/s using hybrid ACELP/TCX techniques

Author

Bessette, B. ; Salami, R. ; Laflamme, C. ; Lefebvre, R.

Author_Institution

Dept. of Electr. Eng., Sherbrooke Univ., Que., Canada

fYear

1999

fDate

1999

Firstpage

7

Lastpage

9

Abstract

A hybrid ACELP/TCX algorithm for coding speech and music signals at 16, 24, and 32 kbit/s is presented. The algorithm switches between algebraic code excited linear prediction (ACELP) and transform coded excitation (TCX) modes on a 20-ms frame basis. Applying TCX on 20 ms frames improved the quality for music signals. Special care was taken to alleviate the switching artifacts between the two modes resulting in a transparent switching process. Subjective test results showed that for speech signals, the performance at 16, 24, and 32 kbit/s, is equivalent to G.722 at 48, 56, and 64 kbit/s, respectively. For music signals, the quality at 24 kbit/s was found equivalent to G.722 at 56 kbit/s. However, at 16 kbit/s, the quality for music was slightly lower than G.722 at 48 kbit/s

Keywords

algebraic codes; audio coding; linear predictive coding; speech codecs; speech coding; transform coding; 16 kbit/s; 20 ms; 24 kbit/s; 32 kbit/s; G.722 codec; algebraic code excited linear prediction; hybrid ACELP/TCX algorithm; music signals; speech coding; subjective test results; transform coded excitation; transparent switching process; wideband audio codec; wideband speech codec; Bandwidth; Encoding; Internet telephony; Multiple signal classification; Qualifications; Speech codecs; Speech coding; Standardization; Testing; Wideband;

fLanguage

English

Publisher

ieee

Conference_Titel

Speech Coding Proceedings, 1999 IEEE Workshop on

Conference_Location

Porvoo

Print_ISBN

0-7803-5651-9

Type

conf

DOI

10.1109/SCFT.1999.781466

Filename

781466