Science & Engineering Research Support soCiety (SERSC)
Hyper-chaos has more than one positive Lyapunov exponents and it has more complex dynamical characteristics than chaos. Hence it becomes a better choice for secure image encryption schemes. In this paper, 3D Arnold cat map can be applied in image encryption, and it has more security and better effect. However, its period is fixed. The original image will be returned to itself if iterating some times. On the basis of 3D Arnold cat map, it presented an algorithm of image encryption which separates the original image to many same blocks and no period.