Title :
A modular approach to speech enhancement with an application to speech coding
Author :
Accardi, Anthony J. ; Cox, Richard V.
Author_Institution :
AT&T Labs.-Res., Florham Park, NJ, USA
Abstract :
Ephraim and Malah´s (1984, 1985) MMSE-LSA speech enhancement algorithm, while robust and effective, is difficult to tune and adjust for the tradeoff between noise reduction and distortion. We suggest a means of generalizing this design, which allows for other estimators besides the MMSE-LSA to be used within the same supporting framework. When a modified version of Ephraim and Van Trees´s (see IEEE Trans. Speech and Audio Proc., vol.3, p.251-66, 1995) spectral domain constrained signal subspace estimator is used in this manner, we obtain a system with greater flexibility and similar performance. We also explore the possibility of using different speech enhancement techniques as pre-processors for different parameter extraction modules of the IS-641 speech coder (a 7.4 kbit/s ACELP codec). We show that such a strategy can increase the quality of the coded speech and lead to a system that is more robust to differing noise types
Keywords :
adaptive codes; linear predictive coding; noise; parameter estimation; spectral analysis; speech coding; speech enhancement; speech intelligibility; vocoders; 7.4 kbit/s; ACELP codec; IS-641 speech coder; MMSE-LSA speech enhancement algorithm; coded speech quality; distortion; modular approach; noise reduction; parameter extraction modules; performance; pre-processors; spectral domain constrained signal subspace estimator; speech coding; Acoustic noise; Additive noise; Background noise; Gaussian noise; Noise level; Noise reduction; Noise robustness; Speech coding; Speech enhancement; Subspace constraints;
Conference_Titel :
Acoustics, Speech, and Signal Processing, 1999. Proceedings., 1999 IEEE International Conference on
Conference_Location :
Phoenix, AZ
Print_ISBN :
0-7803-5041-3
DOI :
10.1109/ICASSP.1999.758097