期刊名称：Journal of Theoretical and Applied Information Technology
印刷版ISSN：1992-8645
电子版ISSN：1817-3195
出版年度：2014
卷号：65
期号：3
出版社：Journal of Theoretical and Applied
摘要：Medical images convey important information to the doctor about a patient�s health condition. Internet transmits these medical images to remote locations of the globe to be examined by expert doctors. But data transmission through unsecured net invokes authentication problems for any image data. This problem of authentication of medical images is addressed in our research as medical image watermarking with patient images. Medical images contain very sensitive information. Watermarking medical images require careful modifications preserving the data in the images. This is being accomplished using RAS (Rivest, Shamir and Adleman) algorithm for patient image encryption and decryption. The host images are set of medical images such as MRI, CT and Ultrasound scans of patient body parts. These medical images are watermarked with encrypted patient image in transform domain using 2D Discrete Wavelet Transform (DWT). The host medical image and watermark image are transformed into wavelet domain and are mixed using two scaling factors alpha and beta. Finally these watermarked medical images are transmitted through the internet along with the secret key that will be used for decryption. At the receiving the embedded encrypted watermark is extracted using 2DWT and decryption key. The robustness of the proposed watermarking techniques is tested with various attacks on the watermarked medical images. Peak-Signal-to-Noise ratios and Normalized cross correlation coefficients are computed to accesses the quality of the watermarked medical images and extracted patient images. The results are produced for three types of medical images with one patient image watermarks using single key by using four wavelets (haar, db, symlets, bior) at four different levels (1,2,3,4).
关键词：Medical Image Watermarking; RAS (Rivest; Shamir and Adleman) algorithm; Discrete Wavelet Transform (DWT); MRI; CT and Ultrasound Images.
