Abstract: Illegal acts of piracy violate the legitimate interests of creators, making copyright protection of multimedia information to become very important. Based on the analysis about the general copyright protection management system,we proposed an efficient model for copyright protection of multimedia information. In the model, watermarking is embedded four times with comprehensive utilization of robust watermarking and fragile watermarking for multimedia; multimedia information is encrypted by the method of full file encryption; special client software, which adopts double buffering mechanism and secure storage mechanism, is used for information decryption. Finally, performance analysis shows that the model improves the security of the DRM system under the premise of not reducing its authority, fairness, and practice.

Key words: Digital rights management(DRM),Robust watermarking,Fragile watermarking,Encryption/Decryption for multimedia, Digital signature