关键词: 混沌映射, 图像加密, 位置置乱, 像素替换, 广义Gray码

Abstract: To solve the shortcoming of encryption efficiency and security of some existing image encryption algorithms, this paper proposes a new image encryption algorithm. Firstly the image is rearranged by using Kent mapping, and then the location of the image is scrambled. The Logistic mapping is used to construct the subscript sequence, and the subscript sequence is used to XOR the pixel of the scrambled image. Finally, the XOR value is replaced with the generalized Gray code. Experiments show that the algorithm is encrypted with the following features：large enough key space, evenly distributed gray histogram, weak correlation of pixels and so on. The proposed algorithm has good security and encryption effect.

Key words: chaotic mapping, image encryption, position scrambling, pixel replacement, generalized Gray code