Video Encrypt Based On Cat Map And H.264

With the features of chaos-aliasing and topological transitivity, the highly sensitive to initial conditions and parameters, chaos is applied to the field of information security, such as chaotic encryption of digital multimedia. And it is an important direction of development of chaos theory for direct service of humanity.In this paper, it is prompted a video encryption method combined H.264video coding standard and high-dimensional (dimension) of generalized chaotic cat map. Compared with the H.264coding standard and the previous video coding standards, it has the low bit rate high-quality, high robustness, and a variety of network-friendly Advantages. Low-dimensional chaotic cat map used transform matric parameters and the number of encryption round as the key used to encrypt, and this has the main disadvantage of small key space. High dimensional generalized chaotic cat maps with two positive Lyapunov exponents, can improve the effect of image scrambling. When used in encryption, transform sub-matrix by multiplying all of the possible number of sorting, encryption rounds and transformation matrix parameters as the key, the key space greatly increases and the safety performance is improved. Under this approach, this paper raises two schemes:First, the YUV video is encrypted and then encoded into H.264video stream; second, the YUV video encoded into H.264video stream and then encrypted. The two schemes is realized on a Linux platform, analyzed and compared the performance of the two programs. What’s more, it’s build embedded Linux development environment and Linux systems, and transformed the H.264codec, and the two schemes on the ARM-Linux platform. The paper’s esearch include:1. Chaotic encryption.. Traditional cryptography theory, a good encryption system should have a high degree of sensitivity of the key, and will be expressly scrambling to change their statistical properties, which coincided with the chaos of topological transitivity and aliasing features as well as on the initial consistent with the highly sensitive nature of the conditions and parameters.2. Extends the cat map to the general cat map, generalizes multi-dimensional cat map transformation matrix, and analyzes key spatial in the cat map encryption.3. H.264compression standard. H.264encoder using predictive coding and transform coding, hybrid coding techniques. Include intra and inter-frame predictive coding, variable block size, multi-frame motion estimation, integer DCT transform and entropy coding methods.4. Embedded Linux development platform, the embedded Linux system and open source software cross-platform migration. The embedded development environment uses host\target mode, this paper studies how to create a cross-compiler environment, how to configure the NFS file system and serial communication. Embedded Linux system includes how to make bootload, modify and compile the kernel, and make the file system. And open source software transplants, and it is transplanted the H.264codec.5. Cat map encryption algorithm. And prompt two sets of video encryption schemes.This work was supported by the National Natural Science Foundation of China under Grant Nos.60572073,60871025and-61172023, the Specialized Research Foundation of Doctoral Subject Point of Education Ministry under Grant No.20114420110003, the Natural Science Foundation of Guangdong Province under Grant Nos.8151009001000060and S2011010001018, and the Science and Technology Program of Guangdong Province under Grant No.2009B010800037.