Abstract: Digital Rights Management（DRM） is becoming a key technology to protect intellectual property of digital contents. Considering the demand of digital content market and the shortcomings of current DRM systems, this paper presents a cryptography-based DRM scheme, which extracts encrypt key from an image dynamically and makes the key choice and updating more flexible. At the same time, to enhance significantly the security of DRM system, a triple-stage encryption mechanism is adopted in the system. Furthermore, user domains are formed using ergodic encryption so that the license can be bound with multiple devices, which allows a user to share digital contents on various devices he owns. The security of the program is proved, the simulation result of operational efficiency and the result of comparison with several mainstream DRM solutions are given.

Key words: Digital Rights Management（DRM）, characteristic image, device fingerprint, user domain, ergodic encryption

摘要： 数字版权保护（DRM）已经成为网络环境下数字内容交易和传播的一种关键保障技术。鉴于我国数字内容市场的需求和目前DRM技术的不足，提出一种在图像中动态提取密钥的方法，使得密钥的选择与更新更加灵活，并建立一个三重加密机制，增强了DRM系统的安全性。同时利用遍历加密的方法将内容许可证与用户的多个终端设备进行绑定，建立起用户域，使用户能在多台设备上共享内容。对方案的安全性进行了证明，给出了运行效率的仿真结果和与目前几个主流DRM方案的比较结果。

关键词: 数字版权保护（DRM）, 特征图像, 机器指纹, 用户域, 遍历加密