Patent ID: 6456965
Filing Date: 2002-09-24
Classification: G10L

Abstract:
A method of estimating the pitch of a segment of a speech signal, comprising the steps of:selecting a set of initial pitch candidates by dividing the pitch range into sub-ranges, applying a pitch cost function to input samples, and selecting a pitch candidate for each said sub-range for which the pitch cost function is maximized, determining an input pitch period using at least one previously calculated pitch value from prior segments of said speech signal; determining whether said determined pitch period from prior segments is short or long; and for each pitch candidate, if said average pitch period is short having just a few harmonics such that it is easier to match time domain waveforms, using a time domain pitch estimation process to evaluate each said pitch candidate, or if said average pitch period is long being more than a few harmonics and not easier to match time domain waveforms, using a frequency domain pitch estimation process to evaluate each said pitch candidate.