A novel color image encryption algorithm using chaotic map and improved RC4

Abstract

In this paper, color image encryption algorithm based on improved RC4 and chaotic maps is proposed. In proposed algorithm, the classic RC4 algorithm in cryptography is improved, and then applied to proposed encryption algorithm. Firstly, the original image is divided into some sub-blocks. Then, the improved RC4 algorithm is applied to the operation between the adjacent two sub-blocks, thereby changes the value of pixels. Finally, the image is scrambled by logistic map. Experimental results show that the original image has a big change and a flat histogram after encrypted, and that the proposed algorithm has an enough large key space and a very high sensitivity to the key.