Design of image group code based on chaotic systems
基于多混沌系统的图像分组密码设计

Chaotic capability will decline after digitalizing chaotic system. Aiming at this question, a chaotic random number generator based on Logistic mapping was presented in this paper, Piecewise Linear Chaotic Mapping (PLCM) and shift mapping defined on (0,1). Through the iterations of different chaotic systems, the generating random sequence was confirmed by four trajectories. Therefore, it has better random characteristic and longer cycle under finite precision. A group image encryption algorithm based on this chaotic random number generator is also presented. This algorithm has stronger robustness. The restore effect is also well while the encryption image is partly damaged or deleted. This algorithm has more control parameters and a large space of keys. It is sensitive to key and it has excellent performance against attacks.