Fixed bit-rate PWI speech coding with variable frame length

Author

Tang, K.W. ; Cheetham, B.M.G.

Author_Institution

Dept. of Electr. Eng. & Electron., Liverpool Univ., UK

Volume

3

fYear

1995

Firstpage

1600

Abstract

This paper presents a harmonic vocoder for digitising speech at fixed low bit-rates based on the prototype waveform interpolation (PWI) technique. A variable frame-length form of this technique is proposed. The basic idea is consistent with that of the original PWI algorithm, but improves its performance at low bit-rates and reduces its computational complexity. This variable frame-length coding technique, which uses vector quantised cepstral coefficients for representing the spectral envelope of individual pitch periods produces good perceptual quality at 2.4 kb/s

Keywords

cepstral analysis; computational complexity; interpolation; speech coding; vector quantisation; vocoders; 2.4 kbit/s; computational complexity; fixed bit-rate PWI speech coding; harmonic vocoder; individual pitch periods; low bit-rate coding; perceptual quality; prototype waveform interpolation; spectral envelope; variable frame length; vector quantised cepstral coefficients; Cepstral analysis; Computational complexity; Decoding; Digital filters; Fourier series; Interpolation; Prototypes; Shape; Speech coding; Vocoders;

fLanguage

English

Publisher

ieee

Conference_Titel

Global Telecommunications Conference, 1995. GLOBECOM '95., IEEE

Print_ISBN

0-7803-2509-5

Type

conf

DOI

10.1109/GLOCOM.1995.500295

Filename

500295