The Research Of Image And Video Encryption Algorithm

With the rapidly development of the Internet communication and multimedia technology, more and more multimedia information is transmitted over the internet and becoming an important way for communication. For example, people use it to exchange all kinds of information and trade online. Hence, the security and transmission of the multimedia information has become a critical and imperative issue. In this paper, the image encryption algorithms in common use are studied, and the performances of digital image encryption and AVI video encryption are analyzed and tested. Some of the conclusions are listed as follows.Firstly, an image encryption algorithm based on improved chaotic cat maps is proposed, in this method, the image is encrypted by diffusion function and improved chaotic cat maps, and this method is proved to have larger key spaces, and also significantly increases the resistance against statistical attacks, differential attacks and cipher-text-only attacks. Secondly, a color image encryption algorithm based on diffusion function and hyperchaos system is proposed, which is used to remedy the drawback of visual secret sharing method. Thirdly, a compression and coding technology for digital image encryption scheme is introduced by imbedding encryption in compression and coding process to reduce storage spaces for image, and experimental results show that this method can not only provide faster encryption, but also uses smaller storage space for compressed image, so we can transmit these images over current bandwidth. Finally, a proper AVI video encryption algorithm based on chaotic system and diffusion function is introduced, which can meet the needs of the larger-scale and real-time characters of AVI video.In this paper, some open issues in this topic as well as the future work are proposed.