Image Encryption Algorithm Based on Chaotic System and Cellular Automata

In order to solve the problem of low efficiency and not safe enough in current image encryption schemes, a novel image encryption algorithm is proposed in this work to improve efficiency and security by employing chaotic system and Cellular Automata. Firstly, horizontal and vertical coordinates of plaintext image pixels are scrambled by the designed row and column scrambling algorithm simultaneously. Secondly, the scrambled image is diffused by the decisive key matrix composed of chaotic sequence regionally. Finally, the diffused image is regarded as the input of Cellular Automata, the CA evolution rule of input is judged according to the chaotic index value, the ciphertext image is obtained after the evolution. Experimental results and theoretical analysis show that the proposed algorithm in this paper has high security, good robustness and can meet the requirement of real-time encrypted communication.