Abstract: Concerning the problems of small key space, bad diffusion speed, low security of one-dimensional cellular automaton, as well as the extra rule storage space and unsatisfactory encryption effect of two-dimensional cellular automaton, we propose an image encryption algorithm based on life-like cellular automaton. Firstly, each pixel of the plain-image is converted into binary matrix. Then, the binary matrix is divided into two identical parts, which are taken as two initial states of the life-like cellular automata. Finally, a rule is selected as the key and the encryption is performed by the evolution of the life-like cellular automata. Experimental results show that the proposed image encryption scheme has a lot of characteristics, including large key space, and high sensitivity to the plaintext and key, which can effectively protect the security of the encrypted image.

Key words: information security, image encryption, life-like cellular automaton