Patent ID: 6230122
Filing Date: 2001-05-08
Classification: G10L

Abstract:
A system for suppressing background noise in audio data, comprising:a detector configured to perform a manipulation process on said audio data, said audio data including speech information, said detector including a speech detector configured to analyze and manipulate said speech information, wherein a first amplitude of said speech information is divided by a second amplitude of said background noise to generate a signal-to-noise ratio for said speech detector, said speech information including digital source speech data that is provided to said speech detector by an analog sound sensor and an analog-to-digital converter, wherein a filter bank generates filtered channel energy by separating said digital source speech data into discrete frequency channels, said speech detector comprising a noise suppressor, a projection module, and a weighting module, said noise suppressor including a subspace module for creating a subspace based upon said background noise, said projection module generating projected channel energy by projecting said filtered channel energy onto said subspace, said weighting module generating noise-suppressed channel energy by applying separate weighting values to each of said discrete frequency channels of said projected channel energy, said separate weighting values being proportional to said signal-to-noise ratios of said discrete frequency channels; anda processor coupled to said system to control said detector and thereby suppress said background noise.