Perceptual evaluation of dynamic cost weighting for unit selection TTS

Unit selection text-to-speech synthesis relies on multiple cost criteria, each encapsulating a different aspect of acoustic and prosodic context at any given concatenation point. For a particular set of criteria, the relative weighting of the resulting costs crucially affects final candidate ranking. We have recently advocated a new weighting strategy based on a data-driven framework separately optimized for each concatenation. In this approach, the cost distribution in every information stream is dynamically leveraged to locally shift weight towards those characteristics that prove most discriminative at this point. To further validate this procedure, this paper presents formal listening evidence suggesting that dynamic cost weighting indeed entails higher perceived TTS quality.