Unit Selection Speech Synthesis in Noise

The paper presents an approach to unit selection speech synthesis in noise. The approach is based on a modification of the speech synthesis method originally published in A.W. Black and P. Taylor (1997), where the distance of a candidate unit from its cluster center is used as the unit selection cost. We found out that using an additional measure evaluating intelligibility for the unit cost may improve the overall understandability of speech in noise. The measure we have chosen for prediction of speech intelligibility in noise is speech intelligibility index (SII). While the calculation of the SII value for each unit in the speech corpus was made off-line, a pink noise was used as a representative noise for the calculation. Listening tests imply that such a simple modification of the unit cost in unit selection synthesis can improve understandability of speech delivered under poor channel conditions