Patent ID: 7379866
Filing Date: 2008-05-27
Classification: G10L

Abstract:
1. A method for suppressing background noise from a speech signal, said method comprising: obtaining an input speech signal; performing linear predictive coding (LPC) analysis on said input speech signal to obtain a z-domain representation of said input speech signal; computing a spectrum tilt and a noise-to-signal ratio (NSR) of said z-domain representation of said input speech signal; obtaining a spectrum tilt of a background noise model; applying a gain to reduce energy of said input speech signal when said NSR is high; reducing a spectral valley energy of said input speech signal when said spectrum tilt of said input speech signal is equivalent to said spectrum tilt of said background noise model; and applying an inverse filter to said input speech signal when said spectrum tilt of said input speech signal is not equivalent to said spectrum tilt of said background noise model, wherein said inverse filter is an inverse of a z-domain representation of said background noise model.