Estimation of perceived speech quality using measuring normalizing blocks

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 (MNBs) 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