Journal ArticleDOI
Multilevel adaptive thresholding and shrinkage technique for denoising using Daubechies complex wavelet transform
TLDR
In this article, a multilevel soft thresholding technique for noise removal in Daubechies complex wavelet transform domain is proposed, which is based on approximate shift invariance and strong edge representation.Abstract:
In this paper, we have proposed a multilevel soft thresholding technique for noise removal in Daubechies complex wavelet transform domain. Two useful properties of Daubechies complex wavelet transform, approximate shift invariance and strong edge representation, have been explored. Most of the uncorrelated noise gets removed by shrinking complex wavelet coefficients at the lowest level, while correlated noise gets removed by only a fraction at lower levels, so we used multilevel thresholding and shrinkage on complex wavelet coefficients. The proposed method firstly detects strong edges using imaginary components of complex coefficients and then applies multilevel thresholding and shrinkage on complex wavelet coefficients in the wavelet domain at non-edge points. The proposed threshold depends on the variance of wavelet coefficients, the mean and the median of absolute wavelet coefficients at a particular level. Dependence of these parameters makes this method adaptive in nature. Results obtained f...read more
Citations
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Journal ArticleDOI
Fusion of multimodal medical images using Daubechies complex wavelet transform - A multiresolution approach
Rajiv Singh,Ashish Khare +1 more
TL;DR: Comparison results prove that performance of the proposed fusion method is better than any of the above existing fusion methods.
Journal ArticleDOI
A novel image de-noising method based on spherical coordinates system
TL;DR: The experimental results compared the improved algorithm with other methods from the peak signal-to-noise ratio, mean square error, and running time, and indicate that improved algorithm is simple and effective.
Journal ArticleDOI
Hybrid dual-tree complex wavelet transform and support vector machine for digital multi-focus image fusion
TL;DR: Experimental results showed that the presented method outperformed the existing methods, in visual effect and in objective evaluation.
Journal ArticleDOI
Performance improvement of a near-infrared CH4 detection device using wavelet-denoising-assisted wavelength modulation technique
TL;DR: By introducing wavelet denoising (WD) in the traditional tunable diode laser absorption spectroscopy (TDLAS), a novel CH 4 detection device based on WD-assisted wavelength modulation technique was experimentally demonstrated.
Journal ArticleDOI
Moving object segmentation in Daubechies complex wavelet domain
TL;DR: A new method for segmentation of moving object which is based on double change detection technique applied on Daubechies complex wavelet coefficients of three consecutive frames is introduced to have high degree of segmentation accuracy than the other state-of-the-art methods.
References
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Journal ArticleDOI
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TL;DR: The authors prove two results about this type of estimator that are unprecedented in several ways: with high probability f/spl circ/*/sub n/ is at least as smooth as f, in any of a wide variety of smoothness measures.
Journal ArticleDOI
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Journal ArticleDOI
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Journal ArticleDOI
The dual-tree complex wavelet transform
TL;DR: Several methods for filter design are described for dual-tree CWT that demonstrates with relatively short filters, an effective invertible approximately analytic wavelet transform can indeed be implemented using the dual- tree approach.
Book ChapterDOI
Translation-Invariant De-Noising
TL;DR: A reconstruction subject to far weaker Gibbs phenomena than thresholding based De-Noising using the traditional orthogonal wavelet transform is produced.