Research Of Digital Watermarking Techniques Based On MPEG-2

With the rapid development of information technology and computer networking, various forms of multimedia digital works (text, image, video, audio, etc.) have to form network, copyright protection has become an urgent need to resolve the issue. It can not only convenient access through the Internet and CD-ROM multimedia information and the original data can be identical copies, resulting in the issue of piracy and copyright disputes has become an increasingly serious social problem. Digital watermarking is the effective way to achieve copyright protection.Although the digital watermarking technology developed by leaps and bounds in recent years, but mainly in the direction of static images. Because of the time domain masking properties of the human visual system is more accurate model has not been completely established. Video Watermarking technology development lags behind static image watermarking technology. The other hand, as a special form of attack video watermarking (insert frame, frame reorganization, etc.), video watermarking has unique character distinct from the static image watermarking.In this paper, analysis of the MPEG-2 encoding technology, and a detailed analysis of the code stream MPEG2 format. Then a DCT-based digital video watermarking scheme is proposed using the characteristics of video watermarking technology. By this way, embedding and extracting watermark in compressed video domain are carried out. Embedded in the site selection, we chose the I-frame video to the embedded watermark. Because all the pixels of I-frame are encoded at the MPEG system, its analysis as static images technology. The watermark information carrier, the choice of color DC coefficient, we can fully guarantee watermark is visible. Furthermore, to improve the security of the watermark, we used Arnold transform for the watermark image, then provides key for digital watermarking system. Related experiments show that the program adopted by the full guarantee of the watermark is visible and robust, and operational complexity is still relatively low.Through the study of this issue, we can acquire the digital watermarking system theory, and for further studies and lay a good foundation. Also, we have gained a deeper understanding of video technology. Finally, I hope that through our efforts, we can help friends as reference for studying digital watermark, and get them apply to practical soon.