Comparing approaches to pitch contour stylization for speech synthesis

This chapter describes two approaches to pitch contour stylization as well as a perception experiment to evaluate and compare both methods. The first approach uses an automatic stylization procedure, based on perceptual criteria. It outputs the sequence of audible pitch events (static tones, dynamic tones, complex dynamic tones) in the utterance. Both the tonal perception model and the algorithm are described in some detail. The second approach, known as close-copy stylization, is a manual procedure in which a straight-line approximation of the pitch contour is obtained interactively, by resynthesis of the stylized contour and auditory comparison with the original. A perception experiment using synthetic stimuli with stylized contours was run in order to compare and evaluate both approaches. The stylized contours can hardly be distinguished from the natural contours. Tonal perception stylization gives slightly better results than straight-line stylization.