A CRT based watermark for multiparty multilevel DRM architecture

In this paper, we propose a joint digital watermarking protocol for the multiparty multilevel DRM architecture using Garner´s algorithm for the Chinese remainder theorem (CRT). Our protocol exploits the incremental nature of the computation of CRT by the Garner´s algorithm. The proposed joint watermarking protocol embeds a single watermark signal into the content while taking care of the various security concerns such as proof of involvement in the distribution chain, nonrepudiation of the involvement and protection against false framing of the different parties involved. Further, in the event of finding an illegal copy of the content, the identities of all the parties involved in that content distribution chain can be traced back by extracting the watermark information.