Abstract：Based on the analysis of wavelet packet traditional threshold denoising algorithm, a new algorithm of wavelet packet multi-threshold speech denoising based on fuzzy control is proposed. The algorithm adopted an improved multi threshold selection method instead of the traditional threshold selection; applied a new threshold function to quantize the bottom frequency coefficients after wavelet packet transform to ensure that the noise signal can be completely filtered out; fuzzy controller can be used to signal amplitude jump and edge roughness and other issues to optimize and correct. By combining these three methods, the speech enhancement process can be carried out adaptively. The experimental results show that compared with the traditional threshold algorithm, this algorithm restore the pure speech information to the greatest extent,effectively improve the accuracy of speech denoising and the signal-to-noise ratio.
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2019, Vol. 40 
