Image Scrambling Scheme Based on Bit-Level Permutation and 2-D Cellular Automata

Cellular automata are suitable for image scrambling because they have favorable properties such as simple regular structure, complex behavior, massive parallelism. Many proposed CA-based Image scrambling methods permute image at gray-level and only change the position of the pixel. In this paper, we present an image scrambling scheme based on bit-level permutation and 2-D cellular automata. Firstly, we convert the original gray image of size M*N into a binary image of size M*8N. Secondly, the binary image is permuted at bit-level by the scrambling matrices generated by 2-D cellular automata. In this way, the pixel position and pixel value can be changed simultaneously. The corresponding simulations and analyses show that the suggested image scrambling scheme exhibits good cryptographic properties.