Objective quality evaluation for low-bit-rate speech coding systems

Author

Kitawaki, Nobuhiro ; Nagabuchi, Hiromi ; Itoh, Kenzo

Author_Institution

Telecommun. Network Labs., NTT, Tokyo, Japan

Volume

6

Issue

2

fYear

1988

fDate

2/1/1988 12:00:00 AM

Firstpage

242

Lastpage

248

Abstract

An LPC (linear predictive coding) cepstrum distance measure (CD) is introduced as an objective measure for estimating the subjective quality of speech signals. Good correspondence between LPC CD and the subjective quality, expressed in terms of both opinion equivalent Q and mean opinion score, are shown. Good repeatability of objective quality evaluation using LPC CD is also shown. A method for generating an artificial voice signal that reflects the characteristics of real speech signals is described. The LPC CD values calculated using this artificial voice are almost the same as those calculated using real speech signals. The speaker-dependency of the coded-speech quality is shown to be an important factor in low-bit-rate speech coding. Even taking this factor into consideration, LPC CD is shown to be effective for estimating the subjective quality

Keywords

encoding; errors; speech analysis and processing; speech synthesis; artificial voice signal; cepstrum distance; coded-speech quality; errors; linear predictive coding; low-bit-rate speech coding systems; objective quality evaluation; speaker-dependency; subjective quality; Cepstrum; Character generation; Distortion measurement; Frequency measurement; Linear predictive coding; Nonlinear distortion; Speech analysis; Speech codecs; Speech coding; Time measurement;

fLanguage

English

Journal_Title

Selected Areas in Communications, IEEE Journal on

Publisher

ieee

ISSN

0733-8716

Type

jour

DOI

10.1109/49.601

Filename

601