Speech enhancement based on a log-spectral amplitude estimator and a postfilter derived from clean speech codebook

In this paper, we propose a single channel speech enhancement system where a postfilter, which is derived from a clean speech codebook, is applied after a log-spectral amplitude estimator. The primary motivation of this approach is to include prior knowledge about clean source signals to improve speech enhancement results. The codebook, which is trained from clean speech database, serves as clean speech spectral constraints on the enhanced speech. By using the prior clean source information, the proposed method can effectively remove the residual noise presented in traditional speech enhancement algorithms while leaving the speech information intact. Experimental results of the proposed speech enhancement system show improvement in residual noise reduction.