Security of Digital Documents For Remote Medical Consultancy

Abstract

Initially, starting with the scrutiny of current watermarking techniques, the thesis introduces few enhanced techniques for medical images that result in better security, robustness and imperceptibility. The thesis is segregated into six chapters. newline newlineChapter 1 presents the fundamental theory behind digital watermarking, categorization of watermarks, significant qualities, performance metrics, key attacks and current applications. Moreover, literature survey of related medical image watermarking techniques is presented including its open issues and probable solutions. Chapter 2 showcases as secure watermarking approach based on DWT-DCT and SVD which makes use of cryptographic algorithm based on chaos theory. Chapter 3 presents a multidirectional, multi scale wavelet transform in the form of NSCT and RDWT to overcome the limitations of wavelet transforms. Further, Chapter 4 discusses a cryptographic technique combined with NSCT-RDWT and SVD to offer low operational cost. Chapter 5 shows the importance of error correcting codes along with DWT-SVD transforms and chaotic encryption to provide a noise tolerant technique. The proposed technique is also investigated using a simple replacement cipher that is implemented only on the text watermark. Lastly, Chapter 6 summarizes the entire thesis and throws some light on the future tasks that could be carried to produce more competent techniques succeeded by references and list of publications newline newline