Research On The Robustness Of Digital Watermark And Its Application In Digital Museum

Digital watermarking technology provides a new solution in copyright protection and becomes a hot spot in the research field of information security. Aiming at problems of right protection and security of multimedia information in digital museum, some researches about the robustness of image and video watermarking technique are carried out as follows:1. Bring out a solution of synchronization of watermark based on DFT, use the maximum points after DFT transform as the template to trace the geometrical attacks the image has undergone based. We use MPDR and the properties of DFT to estimate zooming factor and the angel of rotation. Then get the image with watermark through anti-operation.2. Report a novel method to blind extract the watermark of attacked image. The method use both the stability of singular value decomposition (SVD) against geometric distortion and the stability of discrete wavelet transform(DWT) against common distortion.3. After analyzing compressed video watermarking algorithms, an algorithm embedded watermarking information into DC of I-frame intermediate frequency of Discrete Cosine Transferal (DCT) is proposed. This method not only enhanced robustness, but also decreased the time complexity of the algorithm.4. Using some criteria, the robustness of image and video watermarking algorithms are evaluated, and their range and performance is shown.5. According to the algorithms presented in this paper, we implemented a multimedia watermarking system applicable to digital museum. This system achieved many watermarking algorithm, which can process 2-dimension, 3-dimension and video media respectively, and a balance among the quantity of information embedded, robustness and speediness of algorithm.