Fragile watermarking with permutation code for content-leakage in digital rights management system

In this paper, we present a new scheme of digital rights management (DRM) system employing the fragile watermarking with permutation code for the image distribution via network. General DRM systems are designed to protect the copyright of contents and to trace the source of the illegal distributors based on the user-side watermarking. However, in the typical DRM systems, the original digital contents are temporarily disclosed without the watermarking information inside user's system by the decryption process. Therefore, the user can copy the leaked original content inside the system and illegally redistribute via network without the permission of the content providers. Our work describes the idea of a DRM method which is composed of the incomplete cryptography based on permutation codes and user identification mechanism to control the quality of digital contents. There are two fundamental steps in our proposed cryptography: incomplete encoding and incomplete decoding. These two steps will create the scrambled content that is used as trial content and the watermarked content that is used to prevent unauthorized duplication or business of digital contents, respectively. Experimental results show that the proposed method is suitable for DRM in the network distribution system.