摘要 |
<p>A method for estimating a pitch frequency of an audio signal includes computing a first transform of the signal to a frequency domain over a first time interval (42), and computing a second transform of the signal of the frequency domain over a second time interval (44), which contains the first time interval. A line spectrum of the signal is found, based on the first and second transforms, the spectrum including spectral lines having respective line amplitudes and line frequencies. A utility function (130) that is periodic in the frequencies of the lines in the spectrum is then computed. This function is indicative (158), for each candidate pitch frequency in a given pitch frequency range, of a compatibility of the spectrum with the candidate pitch frequency. The pitch frequency of the speech signal is estimated responsive to the utility function (176, 178).</p> |