Corpus-based extraction of F0 contour generation process model parameters

A corpus-based method was developed for automatic extraction of the F0 contour generation process model parameters (phrase and accent commands). The method first smoothes the observed F0 contour by a piecewise 3rd order polynomial function and finds points of inflection. Then several parameters related to the points are used as input parameters for the predictor of the model commands. Finally the predicted commands are tuned to the observed contour by the analysis-by-synthesis. An experiment was conducted using ATR 504 sentence speech corpus, and the performance close to a rule-based method, also developed by the authors, was obtained. An experiment was further conducted by adding linguistic information of the content of the utterance (such as accent type, depth of bunsetsu boundary) to input parameters. The performance was largely improved; the extraction rates reached around 90 % for phrase commands and 84 % for accent commands.