Visual security assessment for video encryption

Video data security is very important for multimedia applications, such as video surveillance and real time videoconference. Although many video encryption methods have been reported, no systematic visual security assessment means have been proposed. Now, security analysis of video encryption put emphasis only on the encryption algorithm itself. However, the intelligibility of the encrypted video needs also to be investigated. Typically, the objective assessment is required to assess how much the video information in cipher-videos is distorted, shuffled, and unrecognized. In this paper, three visual security assessment methods are presented for video encryption. They are structure distortion, image entropy, and spatial correlation. Experiment results are presented and analyzed. It shows that our scheme can provide objective assessment compliant with subjective assessment, and is also suitable for the security assessment of other selective video encryption algorithms.