Simulation of auditory analysis of pitch: an elaboration on the DWS pitch meter.

Abstract

A model was developed for estimating the pitch of complex sounds that are partially masked by background sound. Our ultimate aim is to obtain a model that can separate two simultaneous sounds on the basis of the harmonic structure of at least one of the sounds. The MDWS model is an extension of the Duifhuis, Willems, and Sluyter pitch meter (DWS) [J. Acoust. Soc. Am. 71, 1568-1580 (1982)] which is a practical implementation of Goldstein's optimum processor theory of pitch perception [J. Acoust. Soc. Am. 54, 1496-1516 (1973)]. The main modifications incorporated in MDWS consist of a more faithful modeling of auditory frequency analysis and of an alteration to the criterion used to decide which fundamental best fits a set of resolved components. Effects of the latter modification were investigated in a comparison between model estimates of the pitch of inharmonic complex signals and results obtained for humans. Furthermore, the accuracy of model estimates of the pitch of periodic signals (among which were synthesized vowel sounds), partially masked by noise, was compared with the just noticeable difference of fundamental frequency of these sounds for human observers. The results of these two tests show that the model estimates come close to human perception.