Perception and analysis of linearly approximated F0 contours in Cantonese speech

Our previous study revealed that F0 variations in Cantonese speech can be sufficiently represented by linear approximations of the observed F0 contours. This was observed with test materials that have relatively limited lexical and segmental variations. In the present work, the generalizability of linear approximation is examined with a large corpus of polysyllabic Cantonese words. Perceptual results clearly validate the effectiveness of linearly approximated F0 contours. Subsequently analysis of the amount of generated linear approximations is carried out. The properties of linear F0 movements in continuous Cantonese speech are learned, particularly in association with different tones. Lastly, two objective evaluations of the modified F0 contours, RMS error and contour correlation are compared with the true perceptual performance. It is found that neither of these objective measurements gives reliable prediction on perceived speech naturalness.