Speech Enhancement Using Optimized Wiener Filter for VoIP Speech Codecs
Seung Ho Han, Sohyeon Jeong, Haotian Yang, J Kim, Won Ryu, Minsoo Hahn · 2007
A speech enhancement technique is indispensable to achieve acceptable speech quality in VoIP systems. This paper proposes a Wiener filter optimized to the estimated SNR of noisy speech for speech enhancement. The proposed noise reduction method is applied as pre-processing before speech coding. The performance of the proposed method is evaluated by the PESQ in various noisy conditions. In this paper, G.711, G.723.1, and G.729A VoIP speech codecs are used for the performance evaluation. The PESQ results show that the performance of our proposed noise reduction scheme outperforms those of the noise suppression in the IS-127 EVRC and the noise reduction in the ETSI standard for the advanced distributed speech recognition front-end.