Image Encryption Using Chaotic Map and Cellular Automata

Recent encryption schemes are not sensitive enough to plain-images, which leads to low robustness and easy vulnerability to attacks. By employing chaotic maps and Cellular Automata, a novel image encryption algorithm is proposed in this work to increase the sensitivity to plain-images and improve security. Firstly, initial values of the two-dimensional Logistic-Sine-Coupling Map and the Logistic-Sine-Cosine Map are calculated by the SHA-256 of the original image, and the process of diffusion is conducted. Secondly, the key matrices are produced by iterating chaotic maps in the process of permutation. The diffused image is scrambled by the index matrices, which are produced by sorting every row or column of the key matrices. Finally, the scrambled image is transformed into cipher-image by using Cellular Automata. Experimental results and theoretical analysis show that the proposed scheme has good security as it can effectively resist various attacks.