This paper constructs a new wavelet half-soft threshold function to finish refining treatment of the wavelet coefficients within the threshold, which is more suitable to the complex and continuous characteristics of the natural signal. Meanwhile, the chaotic searching method is introduced and the adjustable parameters of the threshold function is searched entirely. The study obtains the best estimate of the wavelet coefficients between the hard and soft threshold. Using mean square error (MSE) and signal to noise ratio (SNR) to evaluate the de-noising effect, simulation results show that more details of the original signal can be restored by the retained wavelet coefficients obtained by method in this paper, and filtering effects as well as de-noising quality can be improved.
ZHANG Mo, XI Jian-hui
. Improved wavelet half-soft threshold denoising based on chaotic searching[J]. Journal of Shenyang Aerospace University, 2013
, 30(1)
: 57
-60
.
DOI: 10.3969/j.issn.2095-1248.2013.01.013
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