Transform based Optimized Color Image Watermarking for Securing Multimedia Data

Abstract

Due to advancement of technology and wide propagation of multimedia newlinecontents through internet, it is very easy to get data and users also enjoy the accessibility newlineand benefits of the provided networks by sharing information without awareness of newlinepossibly violating copyrights. Therefore, numerous disputes related to security and newlinevalidations of the multimedia data are raised up. Hence, it is required to search a robust, newlinetrustworthy and highly secured method which provides shield to the multimedia-data newlinefrom their unauthorized use. Out of the various available methods, watermarking newlineprovides an effective solution to prevent manipulation of digital contents by newlineunauthorized persons. It is the technique of implanting an identification code, signature, newlinerandom sequence, image or some other information, etc. in the form of watermark into newlinehost multimedia data. Presently, watermarking is used newline newlinefor numerous applications like; newline newlinecopyright, finger newline- newlineprinting newline newline, broadcast monitoring and newline newline .. newlinedata validation, etc. On the other newlineside, various-technical-challenges like; transparency, robustness, capacity, security, newlineetc. are associated with watermarking technique. Out of these challenges, robustness newlineand imperceptibility play dominant role in the perspective of the protection of the newlinemultimedia contents. Numerous-techniques have been-suggested in the past-for grey newlineimages out of which few are for color-images which offer high imperceptibility but poor newlinerobustness under attacks or vice -versa. newlineThe objective of this Thesis is to propose watermarking algorithms which are newlinesuperior when compared with some existing techniques and provide better robustness newlineagainst various attacks without degrading the visual quality as per human visual system newlinerequirements. newline