An amplitude warping approach to intra-speaker normalization for speech recognition

Abstract

In this paper, we present an intra-speaker, warping factor estimation based on pitch alteration utterance. The feature space distributions of untransformed speech from the pitch alteration utterance of intra-speaker would vary due to the acoustic differences of speech produced by glottis and vocal tract. Therefore, it may be possible to determine the amplitude warping factor by calculating the inverse ratio of input to reference pitch. As the recognition results, the error rate is reduced from 0.4% to 2.3% for digit and word decoding. © Springer-Verlag Berlin Heidelberg 2003.