Copyright Protection Technology Of Multimedia Information Based On Digital Watermarking

In modern world, the rapid development of information technology brought revolution of multimedia information. The form of information changed from words to image or video as the main carrier of information. The progress of network technology makes it available to upload or download resource. The diversity of the sources of the information makes it easier to copy. What’s more, problem of piracy becomes increasingly serious day after day. Then digital watermarking appeared to solve the problem. It provides an effective solution to protect the authority of the multimedia information.For different multimedia information which is to be protected, there are different research areas of digital watermarking. On one hand, for digital prints, the appearance of printer and scanner makes people able to print the text, then scan it, at last spread it through the internet without the approval of the author. Thus what they do leads to piracy. On the other hand,3D video technology develops rapidly. In the system of3D video, center image and depth image are transmitted, while the left-eye image and the right-eye image are presented in front of the audience. So how to protect the authority of3D video also becomes a hot research point. This paper mainly research in protecting the authority of digital print and3D video, proposing corresponding new method and do software implementation of the algorithm. The work mainly consists of the following aspects.1. For the authority protection problem of the digital print. In the circulation of digital print accused by printing and scanning, the process of printing and scanning mainly leads to the attacks of rotating、translation and scaling. Then we propose a digital watermarking method based on image registration which is robust to print-scan attack. First, fix the match point according to the size of the original image. Then, when detecting, use image registration by affine transformation and size change to adjust the image. Meanwhile, during the process of generating the watermark, we use statistical decision to improve the robustness. The experiments show that the method of traditional digital watermarking with the help of registration and statistical decision is robust to geometric attack accused by print-scan attack; it provides an efficient project to protect print authority.2. For the authority protection problem of the3D image. The conversion from2D to3D during the process of pixel translation in3D video brought geometric attack. By analyzing the whole process of Depth-Image-Based rendering which is an important method of2D-3D conversion. We find that the Zero-Parallax-Pixels are translation invariant. So we propose a3D image watermarking method based on image reconstruction of the Zero-Parallax-Pixel. In DIBR, first, mark the pixels which have zero parallax, then reconstruct it as a new image to embed the watermark, at last, renew the center image with the new pixels. When detecting, first the left-eye image and the right-eye image are rendered from the center image with the help of depth image. Then reconstruct the image the same way as embedding, and detect the watermark from the rendered images. Simulation results show that the proposed method is robust to noise and JPEG compression. It can be used in the protection of3D video authority.3. Software implementation of the multimedia information authority protection technology based on digital watermarking. The digital watermarking algorithm against the print and scan attack has been generated as an executable software on the Matlab platform. What’s more, the paper proposed a project to protect the electronic bill, and the project has been realized both on the Matlab platform and the VC6.0platform.Above all, in the paper, two different watermarking methods robust to geometric attack are proposed as well as one method for electronic bill. What’s more, the3D watermarking project draw us lesson that the traditional2D digital watermarking methods can be used to protect the3D image when used properly.