Enhancements to DTW and VQ decision algorithms for speaker recognition

Abstract

Dynamic Time Warping (DTW) and Vector Quantisation (VQ) techniques have been applied with considerable success to speaker verification. It is standard practice to use these techniques to calculate a single distance score, and threshold this value to produce a verification decision. In this paper we examine applying a statistical weighting to a number of parameters extracted using the DTW warp path and VQ decision mechanisms. Results are presented which show that the additional parameters extracted encode further speaker specific information, and can be used to improve upon the speaker verification performance of the baseline systems. The application of a distance normalisation technique, which involves comparing DTW or VQ scores for the claimed identity against other speakers, is also investigated. Speaker verification results for baseline and enhanced DTW and VQ systems are reported for a population of 42 speakers.