Title :
Speech enhancement employing a sigmoid -type gain function with a modified a priori signal-to-noise ratio (SNR) estimator
Author :
Alam, Md Jahangir ; Shaughnessy, Douglas O. ; Selouani, Sid-Ahmed
Author_Institution :
INRS-Energie-Mater.-Telecommun., Univ. du Quebec, Montreal, QC
Abstract :
This paper presents a sigmoid type gain function with a modified a priori signal-to-noise ratio (SNR) estimation approach to single channel speech enhancement in noisy environments. Frequency domain noise reduction techniques are often defined in terms of the a priori SNR. A widely used method to determine the a priori SNR from noisy speech is the decision directed (DD) approach. In the DD approach the a priori SNR depends on the speech spectrum estimation in the previous frame which degrades the noise reduction performance. To overcome this problem a sigmoid type weighting function is proposed with a modified a priori SNR estimator. The performance of the proposed algorithm is evaluated by two objective tests under various noisy environments and it is found that the proposed sigmoidal-shaped gain function produces significant improvements in noise reduction performance compared to that of the conventional Wiener gain.
Keywords :
frequency-domain analysis; speech enhancement; Wiener gain; decision directed approach; frequency domain noise reduction techniques; gain function; noise reduction performance; sigmoid-type gain function; signal-to-noise ratio; speech enhancement; Additive noise; Attenuation; Degradation; Delay estimation; Distortion; Noise reduction; Performance gain; Signal to noise ratio; Speech enhancement; Working environment noise; Signal-to-noise ratio; Wiener filter; sigmoid function; speech enhancement;
Conference_Titel :
Electrical and Computer Engineering, 2008. CCECE 2008. Canadian Conference on
Conference_Location :
Niagara Falls, ON
Print_ISBN :
978-1-4244-1642-4
Electronic_ISBN :
0840-7789
DOI :
10.1109/CCECE.2008.4564612