Conference Paper

Speech enhancement for non-stationary noise environment by adaptivewavelet packet

Dept. of Electr. & Comput. Eng., Hanyang Univ.
DOI: 10.1109/ICASSP.2002.5743779 Conference: Acoustics, Speech, and Signal Processing, 2002. Proceedings. (ICASSP '02). IEEE International Conference on, Volume: 1
Source: IEEE Xplore

ABSTRACT We consider the non-stationary or colored noise estimation by wavelet thresholding method. First, we propose node dependent thresholding for adaptation in colored or non-stationary noise. Next, we suggest a noise estimation method based on spectral entropy using histogram of intensity instead of estimation method based on median absolute deviation (MAD). We use a modified hard thresholding to alleviate time-frequency discontinuities. The proposed methods are evaluated on various noise conditions - white Gaussian noise, car interior noise, F-16 cockpit noise, pink noise, speech babble noise. We compare our proposed methods with the conventional one with level dependent thresholding based on MAD

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