Patent ID: 6035048
Filing Date: 2000-03-07
Classification: G10L

Abstract:
A method for enhancing, within a signal bandwidth, a corrupted audio-frequency signal having a signal component and a noise component, the method comprising:analyzing the corrupted signal into plural sub-band signals, each occupying a frequency sub-band smaller than the signal bandwidth;applying a respective signal gain function to the sub-band signal corresponding to each sub-band, thereby to yield respective gain-modified signals; andsynthesizing the gain-modified signals into an enhanced signal of the signal bandwidth; wherein:(a) within each frequency sub-band, the step of applying a respective signal gain function to a corresponding sub-band signal comprises evaluating a function that is preferentially sensitive to energy in the signal component;(b) within each frequency sub-band, said applying step further comprises applying gain values to the corresponding sub-band signal, wherein said gain values are related to said preferentially sensitive function; and(c) the step of evaluating the preferentially sensitive function comprises measuring a relative amount of speech energy within the corresponding sub-band, and measuring a relative amount of speech energy within a frequency range greater than, but centered on, the corresponding sub-band.