Tamper detection and self-recovery algorithm of color image based on robust embedding of dual visual watermarks using DWT-SVD

摘要

In this paper, we propose a scheme can be divided into two parts: one is about robust embedding of dual visual watermarks using DWT and Singular Value Decomposition (SVD), the other part is about tamper detection and self-recovery algorithm of color image. We stress on the latter part. Dual visual watermarks are original image watermark which is color scale image the same as original image and ownership watermark which is gray scale image, respectively. Both of them are embedded into original image using DWT-SVD to prove robustness. For recovery signal embedding, luminance signal and chrominance signal of original image were embedded into surplus chrominance space of original image using matrix transpose replacement embedding method. For watermark extraction scheme: firstly, threshold value would be set to find tampered region. Then we extract the recovery signals to construct recovery information. Lastly we replace tampered regions with recovery information based on threshold value. We can extract the original image watermark and ownership watermark from recovery image. Experiment demonstrates that the proposed scheme is robust to a wide range of attacks and is good at tampered detection as well as self- recovery of tampered images.