Towards perceptually consistent measures of spectral distance

This paper considers distance measures for determining the deviation between two smoothed short-time speech spectra. Since such distance measures are employed in speech processing applications that either involve or relate to human perceptual judgment, the effectiveness of these measures will be enhanced if they provide results consistent with human speech perception. As a first step, we suggest Flanagan´s results on difference limens for formant frequencies as one basis for checking the perceptual consistency of a measure. A general necessary condition for perceptual consistency is derived for a class of spectral distance measures. A class of perceptually consistent measures obtained through experimental investigations is then described, and results obtained using one such measure under Flanagan´s test conditions are presented.