Systems and methods for reconstructing an audio signal from transformed audio information
A system and method may be configured to reconstruct an audio signal from transformed audio information. The audio signal may be resynthesized based on individual harmonics and corresponding pitches determined from the transformed audio information. Noise may be subtracted from the transformed audio information by interpolating across peak points and across trough points of harmonic pitch paths through the transformed audio information, and subtracting values associated with the trough point interpolations from values associated with the peak point interpolations. Noise between harmonics of the sound may be suppressed in the transformed audio information by centering functions at individual harmonics in the transformed audio information, the functions serving to suppress noise between the harmonics.
1. A method for reconstructing an audio signal from transformed audio information, the method comprising:
obtaining transformed audio information representing a sound, wherein the transformed audio information specifies magnitude of a coefficient related to signal intensity as a function of frequency for the audio signal and time;
subtracting noise from the transformed audio information, wherein subtracting the noise includes:
interpolating across peak points of harmonic pitch paths through the transformed audio information, the peak points lying along harmonic frequencies in the transformed audio information,
interpolating across trough points of harmonic pitch paths through the transformed audio information, the trough points being positioned midway between peak points of adjacent harmonic frequencies in the transformed audio information, and
subtracting values associated with individual ones of the trough point interpolations from values associated with individual ones of the peak point interpolations to yield noise-reduced transformed audio information; and
reconstructing the audio signal based on a reverse transformation of the noise-reduced transformed audio information.
2. The method of claim 1 , wherein splines are used to interpolate across the peak points.
3. The method of claim 1 , wherein splines are used to interpolate across the trough points.
4. The method of claim 1 , wherein polynomial interpolation is used to interpolate across the peak points.
5. The method of claim 1 , wherein polynomial interpolation is used to interpolate across the trough points.