Patent ID: 7043030

Claim:
A noise suppression device comprising: a time to frequency converter configured to perform frequency analyzation of an input time domain signal for conversion to an amplitude spectrum; a noise spectrum unit configured to obtain a noise spectrum of the input time domain signal; a signal to noise calculator configured to obtain a signal to noise ratio from the amplitude spectrum and the noise spectrum; a perceptual weight controller configured to control, based on the signal to noise ratio, first and second perceptual weights; a spectrum subtracter configured to subtract from said amplitude spectrum a product of said noise spectrum and the first perceptual weight as controlled by said perceptual weight controller; a spectrum amplitude suppressor configured to multiply a spectrum obtained from said spectrum subtracter by the second perceptual weight as controlled by said perceptual weight controller, the perceptual weight controller configured to control the second perceptual weight such that the amount of amplitude suppression by the spectrum amplitude suppressor decreases for at least a portion of the spectrum obtained from the spectrum subtracter as the signal-to-noise ratio increases; and a frequency to time converter configured to convert an output of said spectrum amplitude suppressor to a time domain signal.