Cyclic-Shift Chaotic Medical Image Encryption Algorithm Based on Plain Text Key-Stream

With the growing popularity of the Internet and the fast expanding to a variety of medical equipment, medical imaging technology has become increasingly sophisticated, especially the telemedicine is increasing rapidly. Therefore, in the process of transmission and storage of medical image, it is very important to encrypt it. However, compared with ordinary images, medical images contain patient information, which means more data, more rich content and the ability to resist tampering and anti-cutting requires higher. Traditional image chaotic encryption algorithm encrypts the image with preset key value,which leads to a high correlation and a relatively low sensitivity to the secret key. Therefore, the traditional image encryption algorithm cannot meet the needs of the medical image. In this regard, a cyclic shift-Chaotic Medical Image Encryption Algorithm Based on plain text keystream is proposed. According to an established rules to obtain the required encryption of the plain text key-stream of medical image and then use this key to do Scrambling operation by using cyclic shift and Diffusion operation by using skew tent mapping, to ensure that the encryption process is closely related to medical image. The experimental results show that this algorithm has certain advantages in the statistical performance, the sensitivity and the anti-attack ability of the algorithm.