Abstract: To improve the security of the color image encryption scheme,a color image encryption scheme based on chaotic systems is proposed. Firstly, the proposed scheme sets the color image as a three-dimensional matrix which is scrambled by affine transformation. Second, the Logistic chaotic sequence applied to generate the control parameter and auxiliary key is used to encrypt the three-dimensional matrix. Here, we mainly focus on two methods for
encryption processes. One is to generate a chaotic sequence by Logistic map and Henon map, which is used to perform XOR operation with the scrambled components R‘, G‘, B‘ respectively. The other one is to adopt a binary Logistic sequence to select the pixel position for the scrambled components R‘, G‘, B‘ image, and then applying the Henon map and Logistic map with the auxiliary key to perform the replacement encryption. Based on this, an encrypted image is synthesized. Simulation results show that the proposed image encryption scheme can implement better encryption and achieve higher security performance.

Key words: color image encryption, chaotic systems, affine transformation, Logistic map, Henon map, security performance