System and method of processing a sound signal including transforming the sound signal into a frequency-chirp domain

摘要

A system and method may be configured to process an audio signal. The system and method may track pitch, chirp rate, and/or harmonic envelope across the audio signal, may reconstruct sound represented in the audio signal, and/or may segment or classify the audio signal. A transform may be performed on the audio signal to place the audio signal in a frequency chirp domain that enhances the sound parameter tracking, reconstruction, and/or classification.

主权项

1. A method of processing a sound signal comprising a harmonic sound having multiple harmonics, the method comprising:
obtaining, by a computer processor, a first portion of the sound signal; transforming the first portion of the sound signal from time domain using a set of filters to generate a set of transform coefficients, each filter being specified by a chirp rate and a frequency, the set of filters comprising different chirp rate and frequency values; generating a multi-dimensional representation using the computer processor, wherein:
a first domain corresponds to frequency,a second domain corresponds to fractional chirp rate,each transform coefficient of the multi-dimensional representation corresponds to a fractional chirp rate in the second domain and a frequency in the first domain,the fractional chirp rate in the second domain is determined by dividing a chirp rate of a corresponding filter by a frequency of the corresponding filter; determining a first common fractional chirp rate corresponding to the multiple harmonics of the harmonic sound in the first portion of the sound signal using the multi-dimensional representation, wherein a chirp rate of a nth (n being a positive integer) harmonic of the multiple harmonics divided by a frequency of the nth harmonic of the multiple harmonics is equal to the first common fractional chirp rate; determining a pitch corresponding to the multiple harmonics in the first portion of the sound signal using the first common fractional chirp rate; generating multiple synthesized harmonics using an oscillator and the pitch for each harmonic of the multiple harmonics; and summing the multiple synthesized harmonics to obtain an audio signal.