Analysis and synthesis of Cantonese F0 contours based on the command-response model

Cantonese is a well-known Chinese dialect with a quite complex tone system. We have applied the command-response model to represent F₀ contours of Cantonese speech by defining a set of appropriate tone command patterns. In this paper, the analysis is extended to Cantonese utterances at three different speech rates. By incorporating the effects of tone coarticulation, word accentuation and phrase intonation, the model gives high accuracy of approximations to Cantonese speech F₀ contours, and hence provides a much better means to quantitatively describe the F₀ contours than the traditional 5-level tone code system. The distributions of timing and amplitudes of commands are investigated, based on which a set of rules is used for synthesis of Cantonese F₀ contours. The validity of the current approach is confirmed by perceptual evaluation of Cantonese synthetic speech.