Patent ID: 7660718

Claim:
A system for determining a pitch of speech from a speech signal, the system including: (1) an input device to receive the speech and generate the speech signal; and (2) a processor structured to: (a) distinguish the speech signal into voiced, unvoiced or silenced sections using speech signal energy levels; (b) apply a Fourier Transform to the voiced speech signal section and obtain speech signal parameters; (c) determine peaks of the Fourier transformed voiced speech signal section; (d) select partials by tracking the speech signal parameters of the determined peaks over a plurality of frames of the speech signal to determine trajectories; and (e) determine the pitch from the selected partials using a two-way mismatch error calculation, the two-way mismatch error calculation including: setting a trial fundamental frequency (ƒ fund ); determining a plurality of predicted harmonics corresponding to the trial fundamental frequency; for one of the plurality of predicted harmonics, determining if any of the selected partials is within (ƒ fund /2) of the predicted harmonic; setting a harmonic frequency error equal to a frequency value of the predicted harmonic in response to determining that none of the selected partials is within (ƒ fund /2) of the predicted harmonic; and determining whether to set the pitch equal to the trial fundamental frequency based at least in part on the harmonic frequency error.