[1]
Image Watermarking Using Hybrid Discrete Wavelet Transform (DWT) - Singular Value Decomposition (SVD) Algorithm
Iram Khan & Abdul Samee Khan
The use of images, text and video has become inevitable in today s rapidly advancing and growing digital world. It has been greatly assisted by the contributions of information technology in bringing about state of the art high speed and secure transmission and reception
systems. Content transmission through e-mails, hard media like hard disk drives (HDD),compact discs (CD), digital video discs (DVD) etc., have made things simpler, safer and faster.
Digital images can be captured easily with scanners, digital cameras and camcorders, and transmitted easily over the Internet.With the advent of tele based services, numerous merits have been reported like cutting down
of transportation time of patient to meet the doctor or hospital, cutting down of cost due to internet based transmission and reception and also efficient patient monitoring and treatment due to systematic and methodological secured storage of the patient information in the hospital
s data base for future access.
"Watermarking" is a process of hiding digital information in original data, to increase robustness and security using the different technique like Discrete Wavelet Transform (DWT) and Singular Value Decomposition (SVD).Methods till date result in good security but they
are not robust enough against different attacks. The aim of this research work is to develop a robust and secure watermarking scheme against various sorts of attacks. The robustness and security is increased by combining DWT and SVD. Accordingly an efficient scheme is
developed that is having better MSE and PSNR against a wide range of attacks.
Keywords: Digital Wavelet Transform, Singular Value Decomposition, Digital Watermarking, Mean Square Error, Peak Signal to Noise Ratio, Noise Attacks
[2]
Review and Analysis of Optical Coherence Tomography (OCT) mages as AS-Modality
ShwetaChouksey & Dr Sunil Phulre
Recently, compressive sampling has expected noteworthy attention as an
promising technique for rapid volumetric image techniques . This paper investigated
optical coherence tomography (OCT) image acquisition using compressive sampling
techniques .Previous researches used the multidimensional wavelet transform as the
domain of sparsification for recovering OCT images in volumes. In this paper we
analyzed and compared the potential and efficiency of other image transforms to recreate
the similar OCT image. The two quantitative measures, the mean square errorand the
structural similarity index, were applied to compare the quality of the reconstructed
volumetric images. We observed that fast fourier transformation and wavelet
transformation both are able to reconstruct OCT image volumes for the orthogonal
sparse sampling masks used in this report, but with different merits.