Improving the Understandability of Speech Synthesis by Modeling Speech in Noise

Abstract

Although the quality of synthetic speech has increased dramatically in the past several years, many people still have difficulty understanding speech produced by even the highest quality synthesizers. We describe an approach to improve understandability of synthetic speech using speech in noise. Natural speech in noise is a change in the style of speech that is used by people to improve the understandability to the listener when speaking in poor channel conditions. We show that altering the presentation of synthetic speech in similar ways also improves understandability. Further, we discuss methods of obtaining speech in noise for use in speech synthesis, as well as the results of an evaluation of several synthetic voices that "speak in noise".