Combining Mexican hat wavelet and spread spectrum for adaptive watermarking and its statistical detection using medical images

2017 ◽  
Vol 78 (10) ◽  
pp. 12647-12661 ◽  
Author(s):  
D. S. Chauhan ◽  
A. K. Singh ◽  
A. Adarsh ◽  
B. Kumar ◽  
J. P. Saini
Author(s):  
LI ZENG ◽  
JIQIANG GUO ◽  
CHENCHENG HUANG

In this paper, a non-tensor product method for constructing three-dimension (3D) mother wavelets by back-projecting two dimension (2D) mother wavelets is presented. We have proved that if a 2D mother wavelet satisfies certain conditions, the back-projection of the 2D mother wavelet is a 3D mother wavelet. And the construction instances of 3D Mexican-hat wavelet and 3D Meyer wavelet are given. These examples imply that we can get some new 3D mother wavelets from known 1D or 2D mother wavelets by using back-projecting method. This method inaugurates a new approach for constructing non-tensor product 3D wavelet. In addition, the non-tensor product 3D Mexican-hat wavelet is used for detecting the edge of two 3D images in our experimental section. Compared with the Mallat's maximum wavelet module approach which uses 3D directional wavelets, experimental results show it can obtain better outcome especial for the edge which the orientation is not along the coordinate axis. Furthermore, the edge is more fine, and the computational cost is much smaller. The non-tensor product mother wavelets constructed by using the method of this paper also can be widely used for compression, filtering and denoising of 3D images.


2009 ◽  
Vol 29 (1) ◽  
pp. 197-202 ◽  
Author(s):  
周翔 Zhou Xiang ◽  
赵宏 Zhao Hong

2005 ◽  
Vol 201 ◽  
pp. 71-74
Author(s):  
R. Belén Barreiro ◽  
Michael P. Hobson ◽  
Anthony N. Lasenby ◽  
Patricio Vielva ◽  
Enrique Martínez-González ◽  
...  

A combined technique using the maximum-entropy method (MEM) and the mexican hat wavelet (MHW) to separate and reconstruct the physical components of the microwave sky is presented. We apply this method to simulated observations by the ESA Planck satellite in small patches of the sky. The reconstructed maps of the CMB and foregrounds are improved as compared to those obtained with MEM on its own. Moreover, more accurate point source catalogues are produced at each observing frequency. This technique may also be extended to deal with other multifrequency CMB experiments, including all-sky data.


Author(s):  
Zhi Zhou ◽  
Yingzi Du ◽  
George G. Rodney ◽  
Martin F. Schneider

2001 ◽  
Vol 328 (1) ◽  
pp. 1-16 ◽  
Author(s):  
P. Vielva ◽  
R.B. Barreiro ◽  
M.P. Hobson ◽  
E. Martínez-González ◽  
A.N. Lasenby ◽  
...  

2015 ◽  
Vol 83 (3) ◽  
pp. 2133-2150 ◽  
Author(s):  
Amit Kumar Singh ◽  
Mayank Dave ◽  
Anand Mohan

1999 ◽  
Vol 6 (5-6) ◽  
pp. 267-272 ◽  
Author(s):  
J.N. Watson ◽  
P.S. Addison ◽  
A. Sibbald

This paper presents the results of feasibility study into the application of the wavelet transform signal processing method to sonic based non-destructive testing techniques. Finite element generated data from cast in situ foundation piles were collated and processed using both continuous and discrete wavelet transform techniques. Results were compared with conventional Fourier based methods. The discrete Daubechies wavelets and the continuous Mexican hat wavelet were used and their relative merits investigated. It was found that both the continuous Mexican hat and discrete Daubechies D8 wavelets were significantly better at locating the pile toe compared than the Fourier filtered case. The wavelet transform method was then applied to field test data and found to be successful in facilitating the detection of the pile toe.


2009 ◽  
Vol 59 (12) ◽  
Author(s):  
Ozgur Ustundag ◽  
Erdal Dinc ◽  
Dumitru Baleanu

The simultaneous determination of pyridoxine hydrochloride (B6) and isoniazide (INH) in tablets was performed by using the Mexican hat wavelet function (MEXH). The absorption spectra of B6, INH and their samples were recorded in the spectral range of 200-330 nm. Linear regression functions for B6 and INH in the linear concentration range of 5-45 mg/mL were obtained by measuring the transformed signals at 253.5 nm corresponding to the zero-crossing point for INH and at 270.6 nm corresponding to the zero-points for B6, respectively. The validation of MEXH method was performed by using the synthetic mixtures. The percent mean recoveries and their relative standard deviations were found as 98.7% and 2.06 for B6 and 98.9 % and 1.89 for INH in the synthetic mixture analysis. The MEXH method was applied to the real samples and a good sensitivity and selectivity was reported. The MEXH method was sucessfully compared with classical derivative method.


2021 ◽  
pp. 299-317
Author(s):  
Abhishek Singh ◽  
Aparna Rawat ◽  
Nikhila Raghuthaman

2016 ◽  
Vol 27 (6) ◽  
pp. 468-483 ◽  
Author(s):  
R. S. Pathak ◽  
Abhishek Singh

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