A New Method of Noise Estimation and Non-linear Spectral Subtraction Used in Speech Recognition
Jie Zhu · Jisuanji gongcheng · 2003
A new noise estimation and non-linear spectral subtraction algorithm is proposed in this article. The usual noise estimation is based on voice activity detection (VAD) deteriorates quickly when the SNR is low. This article proposed a nes noise estimation which is based on energy clustering and is independent of the VAD. It also puts forward an improved non-linear spectral subtraction algorithm. The new spectral subtraction algorithm determines the over subtraction factor according to the local SNR in one mel channel. This method reduces the speech spectral distortion in the mean time of effectively restraining the noise.