Patent ID: 7895033

Claim:
A computer-implemented method of determining whether two or more band-pass signals of an input acoustic signal includes harmonics of a fundamental frequency, comprising: in a computing device, receiving the input signal; in the computing device, filtering the input acoustic signal by a first band-pass filter to obtain a first band-pass signal, a center frequency of the first band-pass signal being a first multiple of the fundamental frequency; in the computing device, filtering the input acoustic signal by a second band-pass filter to obtain a second band-pass signal, a center frequency of the second band-pass signal being a second multiple of the fundamental frequency; in the computing device, measuring first distances between a first set of two or more significant points of the first band-pass signal, the first set being adapted according to an assumed harmonic order of the first band-pass signal; in the computing device, measuring second distances between a second set of two or more significant points of the second band-pass signal, the second set being adapted according to an assumed harmonic order of the second band-pass signal; wherein each of said significant points is one of a zero crossing point, a local maxima, a local minima or a threshold crossing of said first band pass signal; the computing device, comparing the first and second measured distances by calculating differences between each of the measured distances to determine difference values; in the computing device, determining that the first band-pass signal and the second band-pass signal are harmonics of a same fundamental frequency in response to the calculated difference values being below a predetermined threshold value; and in the computing device, mapping the calculated difference values to an evidence value in the range of zero to one, wherein the evidence values represent whether the first band-pass signal and the second band-pass signal are harmonics of the same fundamental frequency.