Performance evaluation of objective quality measures for coded speech

Speech coding is a basic technique that is indispensable to multimedia and personal communications, which require digital coding of the speech signal and information compression. Up to the present, the quality of the speech coding method has been examined by "subjective measures" where test subjects examine the quality of the coded speech. Since, however, subjective measures require tremendous time and effort, it is desired to develop "objective measures" that estimate the subjective quality based on the physical features of the coded speech. There have been proposed several methods to provide objective measures for the coded speech, but it has been difficult to compare their performance since there is no common performance evaluation method. This article first proposes a performance evaluation method for objective measures, which is then used to compare the performances of typical objective measures. It is shown that, under certain conditions, the subjective quality can be estimated by objective measures with the same accuracy as that of subjective measures. In other words, it is shown that the proposed method is practically useful. (C) 2000 Scripta Technica.