A method for automatic extraction of parameters of the fundamental frequency contour

The process of generating an F0 contour has been modeled quite accurately in mathematical terms by Fujisaki and his coworkers, but the derivation of the underlying commands from an observed F0 contour is an inverse problem that cannot be solved analytically. Although it can be solved by successive approximation, a good first-order approximation is necessary to guarantee an efficient and accurate search for the optimum solution. The present paper describes a method for pre-processing an observed F0 contour to obtain a smooth contour, from which a good first-order approximation can be analytically obtained. Experimental results show that correct extraction rates for the accent and the phrase commands are about 90% and 79%, respectively.