A contrast-sensitive reversible visible image watermarking technique

A reversible (also called lossless, distortion-free, or invertible) visible watermarking scheme is proposed to satisfy the applications, in which the visible watermark is expected to combat copyright piracy but can be removed to losslessly recover the original image. We transparently reveal the watermark image by overlapping it on a user-specified region of the host image through adaptively adjusting the pixel values beneath the watermark, depending on the human visual system-based scaling factors. In order to achieve reversibility, a reconstruction/ recovery packet, which is utilized to restore the watermarked area, is reversibly inserted into non-visibly-watermarked region. The packet is established according to the difference image between the original image and its approximate version instead of its visibly watermarked version so as to alleviate its overhead. For the generation of the approximation, we develop a simple prediction technique that makes use of the unaltered neighboring pixels as auxiliary information. The recovery packet is uniquely encoded before hiding so that the original watermark pattern can be reconstructed based on the encoded packet. In this way, the image recovery process is carried out without needing the availability of the watermark. In addition, our method adopts data compression for further reduction in the recovery packet size and improvement in embedding capacity. The experimental results demonstrate the superiority of the proposed scheme compared to the existing methods

Analysis of Digital Watermarking Techniques Using Transform-Based Function

Security and protection of digital data is always a challenging job over the internet. For the protection and copyright of digital multimedia data used digital watermarking techniques. The digital watermarking techniques protect the copyright protection of digital multimedia data. Digital watermarking techniques used to transform based function for the processing of watermark embedding. The transform-based function is a texture feature dominated property. The texture feature is the most important part of the digital image. In this paper study and analysis of transform-based digital image watermarking. The transform-based digital image watermarking using the function of DCT, DWT, IWT and SHIFT. In the family of transform, the function used the layered transform function is wavelet transform function, and other is the shift key point transform function. For simulation used MATLAB software and used standard image dataset and symbol for the process of embedding. For the validation of transform function estimate, four well know parameter such as encoding time, decoding time, PSNR, and the value of NC

ICA for watermarking digital images

A domain independent ICA-based approach to watermarking is presented. This approach can be used on images, music or video to embed either a robust or fragile watermark. In the case of robust watermarking, the method shows high information rate and robustness against malicious and non-malicious attacks, while keeping a low induced distortion. The fragile watermarking scheme, on the other hand, shows high sensitivity to tampering attempts while keeping the requirement for high information rate and low distortion. The improved performance is achieved by employing a set of statistically independent sources (the independent components) as the feature space and principled statistical decoding methods. The performance of the suggested method is compared to other state of the art approaches. The paper focuses on applying the method to digitized images although the same approach can be used for other media, such as music or video