Open Access

Vector Quantization of Harmonic Magnitudes in Speech Coding Applications—A Survey and New Technique

EURASIP Journal on Advances in Signal Processing20042004:620648

Received: 29 October 2003

Published: 27 December 2004


A harmonic coder extracts the harmonic components of a signal and represents them efficiently using a few parameters. The principles of harmonic coding have become quite successful and several standardized speech and audio coders are based on it. One of the key issues in harmonic coder design is in the quantization of harmonic magnitudes, where many propositions have appeared in the literature. The objective of this paper is to provide a survey of the various techniques that have appeared in the literature for vector quantization of harmonic magnitudes, with emphasis on those adopted by the major speech coding standards; these include constant magnitude approximation, partial quantization, dimension conversion, and variable-dimension vector quantization (VDVQ). In addition, a refined VDVQ technique is proposed where experimental data are provided to demonstrate its effectiveness.

Keywords and phrases

harmonic magnitude vector quantization speech coding variable-dimension vector quantization spectral distortion

Authors’ Affiliations

Media Laboratory, DoCoMo Communications Laboratories USA


© Chu 2004

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.