Copyright © 2008 The Institute of Electronics, Information and Communication Engineers
Special Section on Robust Speech Processing in Realistic Environments -- Papers -- Speech Enhancement |
Multichannel Speech Enhancement Based on Generalized Gamma Prior Distribution with Its Online Adaptive Estimation
1 The author is with Institute for Infocomm Research, 21 HengMuiKeng Terrace, Singapore 119613. E-mail: hdtran{at}i2r.a-star.edu.sg, 2 The author is with the Graduate School of Information Science, Nagoya University, Nagoya-shi, 464–8601 Japan., 3 The author is with the Graduate School of Information Engineering, Meijo University, Nagoya-shi, 468–8502 Japan.
| Abstract |
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We present a multichannel speech enhancement method based on MAP speech spectral magnitude estimation using a generalized gamma model of speech prior distribution, where the model parameters are adapted from actual noisy speech in a frame-by-frame manner. The utilization of a more general prior distribution with its online adaptive estimation is shown to be effective for speech spectral estimation in noisy environments. Furthermore, the multi-channel information in terms of cross-channel statistics are shown to be useful to better adapt the prior distribution parameters to the actual observation, resulting in better performance of speech enhancement algorithm. We tested the proposed algorithm in an in-car speech database and obtained significant improvements of the speech recognition performance, particularly under non-stationary noise conditions such as music, air-conditioner and open window.
Key Words: multi-channel speech enhancement, speech recognition, generalized gamma distribution, moment matching
Manuscript received July 9, 2007. Manuscript revised September 14, 2007.