Efficient musical noise suppression for speech enhancement system

Noise reduction techniques that are relying on spectral weighting rules often generate annoying musical noise artifacts in the processed signal. In this paper, we present a postfilter (PF) for the spectral weighting gains that is capable of reducing musical noise in a simple but efficient way. It includes a robust detector for speech pauses and low SNR conditions and adaptively smoothes the weighting gains over frequency based on soft-decisions. Objective and subjective measurements show consistent improvements if the postfilter is applied to conventional noise reduction techniques.