Stephen D. Voran

Abstract: We describe a new approach to the estimation of perceived speech quality. The approach uses a simple, but effective, perceptual transformation to emulate hearing and a hierarchy of Measuring Normalizing Blocks (MNB's) to emulate auditory judgment. The resulting estimates were correlated with the results of seven subjective listening tests. Together, these seven tests include 182 4-kHz bandwidth speech codecs, transmission systems, and reference conditions, with bit-rates ranging from 2.4 to 64 kbps. When compared with six other estimators, the MNB approach offers significant improvements in many cases, particularly at lower bit-rates, and when bit errors or frame erasures are present.

Keywords: speech coding; bandwidth; Testing; auditory system; speech codecs; frequency estimation; frequency measurement; speech analysis; time measurement

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