Mixed Fourier/Walsh transform scheme for speech coding at 4.0 kbit/s

Author

Spanias, A.S. ; Loizou, P.C.

Author_Institution

Dept. of Electr. Eng., Arizona State Univ., Tempe, AZ, USA

Volume

139

Issue

5

fYear

1992

Firstpage

473

Lastpage

481

Abstract

A mixed Fourier/Walsh transform scheme for speech coding is proposed. A set of harmonically structured frequency components is used to represent narrowband components of speech. The broadband residual is characterised by a small number of sequency components. The frequencies and sequences of the transform components are determined by sampling the short-time Fourier and Walsh transforms, respectively. The magnitudes and phases of the Fourier components and the amplitudes of the Walsh components are determined using an iterative algorithm based on the Gauss-Seidel method. A vector quantisation (VQ) scheme is developed to encode the frequency and the sequency components. Results and subjective evaluations are given for speech coding at 4.0 kbit/s.<>

Keywords

data compression; encoding; fast Fourier transforms; iterative methods; speech analysis and processing; 4.0 kbit/s; DFT; Fourier components; Fourier/Walsh transform; Gauss-Seidel; VQ; Walsh components; broadband residual; harmonically structured frequency components; iterative algorithm; magnitudes; narrowband components; phases; sequency components; short time Fourier transform; speech coding; subjective evaluations; transform components; vector quantisation;

fLanguage

English

Journal_Title

Communications, Speech and Vision, IEE Proceedings I

Publisher

iet

ISSN

0956-3776

Type

jour

Filename

161509