Research On Robust Digital Watermarking Algorithm And Apply It In The DRM

With the rapid development of Internet, interest in the topic of digital watermarking expanded rapidly because the Internet enable the perfect copying and distribution of copyrighted material to almost anywhere in the world at almost no cost. For this reason, digital watermarking is commonly used for copyright protection to prevent piracy and illegal duplication of digital copyrighted content.DRM systems can be used to control private performances and displays of digital content. Nowadays, Digital rights management (DRM) is increasingly becoming a necessity for content management and distribution in highly networked environments such as the Internet. DRM systems incorporate encryption, conditional access, copy control mechanisms, content identification and tracing mechanisms. Using the digital watermarking techniques, copy control mechanism and tracing mechanism can be implemented. Thus, these two fields together can provide complete protection of the digital media.Though there are many digital watermarking algorithms, little research focus on dual watermarking algorithm. And most of the watermarking algorithm couldn't integrate with the DRM. In this paper, two dual watermarking algorithms are proposed, one is based on DCT, and the other is based on DWT-SVD. First, a watermark of the owner is embedded in the digital media. And the buyer's watermark will be embedded when the buyer obtain the digital media at our digital rights management system. DCT-based watermark algorithm embeds the watermark of copyright owner into the low and middle frequency coefficients of original image, and then the watermark of custom is embedded in the DC coefficients of original image. And in the SVD-DWT based algorithm, first the watermark of custom is embedded in the DWT coefficients of watermark image of owner, and then the watermark of owner is embedded into the DWT coefficients of original image based on HVS. Experiments demonstrate the validity of these two algorithms. Based on the rules of our digital rights management, pirated media will be refused to show by the media player, and the pirate will be traced. Thus, this mechanism could prevent illegal copying and dissemination digital media during the entire life cycle of digital media.