Speech Enhancement based on Wavelet Thresholding the Multitaper Spectrum Combined with Noise Estimation Algorithm

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P.Sunitha 1,* K.Satya Prasad 1

1. Dept. of ECE, JNTUK,India

* Corresponding author.

DOI: https://doi.org/10.5815/ijigsp.2019.09.05

Received: 26 May 2019 / Revised: 12 Jun. 2019 / Accepted: 26 Jun. 2019 / Published: 8 Sep. 2019

Index Terms

Speech Enhancement, Wavelet thresholding, Multitaper Power Spectrum, Noise power estimation, smoothing parameter, SNR, threshold


This paper presents a method to reduce the musical noise encountered with the most of the frequency domain speech enhancement algorithms. Musical Noise is a phenomenon which occurs due to random spectral speaks in each speech frame, because of large variance and inaccurate estimate of spectra of noisy speech and noise signals. In order to get low variance spectral estimate, this paper uses a method based on wavelet thresholding the multitaper spectrum combined with  noise estimation algorithm, which estimates noise spectrum based on the spectral average of past and present according to a predetermined weighting factor to reduce the musical noise. To evaluate the performance of this method, sine multitapers were used and the spectral coefficients are threshold using Wavelet thresholding to get low variance spectrum .In this paper, both scale dependent, independent thresholdings with soft and hard thresholding using Daubauchies wavelet were used to evaluate the proposed method in terms of objective quality measures under eight different types of real-world noises at three distortions of input SNR. To predict the speech quality in presence of noise, objective quality measures like Segmental SNR ,Weighted Spectral Slope Distance ,Log Likelihood Ratio, Perceptual Evaluation of Speech Quality (PESQ) and composite measures are compared against wavelet de-noising techniques, Spectral Subtraction and Multiband Spectral Subtraction  provides consistent performance to all eight different noises in most of the cases considered.

Cite This Paper

P.Sunitha, K.Satya Prasad, "Speech Enhancement based on Wavelet Thresholding the Multitaper Spectrum Combined with Noise Estimation Algorithm", International Journal of Image, Graphics and Signal Processing(IJIGSP), Vol.11, No.9, pp. 44-55, 2019. DOI: 10.5815/ijigsp.2019.09.05


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