Instrumental Assessment of Prosodic Quality for Text-to-Speech Signals

Formal parameters of speech prosody are investigated concerning their ability to estimate the perceptual quality of text-to-speech (TTS) signals. The study is carried out for the German language using a broad databasis comprising a wide range of TTS systems and text materials. 18 purely acoustic markers, derived from F_o and vocalic/consonantal durations, are analysed individually and in conjunction via cross-validated regression models. The F_o slope within voiced segments proves particularly useful when integrated in a nonlinear fashion, whereas measures of durational variation perform comparably weak. The results highlight a strong potential for instrumental estimation techniques of TTS quality.