Method of estimating the pitch of a speech acoustic signal and speech recognition system using the same.

摘要

The present invention relates to a method of estimating the pitch of a speech acoustic signal and to a speech recognition system using the same. None of the known algorithms is fully satisfactory, each for several reasons: because it requires long and complicated calculations, because it is necessary to consider the speech signal for long times, because in case an error in the estimate is made, such error is transmitted in the following estimates, etc. The method of the present invention operates on the peaks of the voiced speech signal realizing a search of peaks through a time-energy two-dimensional criterion, in contrast with conventional methods of type PAD (Peak Amplitude Detector) wherein the criterion was essentially one-dimensional (time only). <IMAGE>