Robust and Imperceptible Watermarking Techniques for Multimedia Data

Abstract

In today s modern world, it is easily accessible to replicate and broadcast digital content through the Internet. There are three different modes to shield multimedia contents such as newlinesteganography, cryptography and watermarking. Among them watermarking is the most newlinepopular technique and holds excessive ability. Digital watermarking gained wide interest in the newlinefield of multimedia objects. Digital watermarking systems are implemented to assure data newlineauthentication, copyright protection in multimedia data transmission. Moreover, it guarantees newlineto shield the digital media from malicious attacks, piracy, interfering, and distribution of newlineinformation. Digital watermarking is broadly pre-owned as a robust technique for enhancing newlinetrust in the distribution of multimedia contents. In this thesis, transform-domain-based robust, newlinesecure and imperceptible watermarking schemes are presented using encryption and newlineoptimization techniques for color images. A new watermarking and encryption results are newlinedefined based on these methods. The main purpose of this work is to increase the robustness, newlineimperceptibility, security, and embedding capacity of multimedia data. The first objective is newlineimplemented to achieve a secure and robust watermarking system for color images. The newlinepurpose of the second objective is to boost the robustness without damaging the image quality newlineof the signed images. In the third objective security, embedding capacity, and robustness are newlineimproved with the wavelet fusion method. In the last objective, multiple watermarking based newlineon transform-domain techniques is implemented to attain imperceptibility and robustness. newlineThese four objectives are also capable of resisting some image processing attacks. The newlineproposed techniques achieve good performance in terms of Peak Signal-to-Noise Ratio newline(PSNR), Normalized Correlation (NC), Number of Changing Pixel Rate (NPCR), and Unified newlineAverage Changed Intensity (UACI) and found to be better when compared with previous newlineapproaches. newline newline