Attack on a Nonlinear Inter-Pixel Computing and Swapping Based Permutation Approach

In this paper, a chaos-based image encryption scheme using nonlinear inter-pixel computing and swapping based permutation approach [1] (NICSP) is analyzed, a keystream recover algorithm on one-round is proposed by constructing a middle vector. With the keystream recover algorithm, the keystream, which is equivalent to the key, can be recovered when NICSP just employ one-round. Data complexity and computation complexity are both O(log9 MN), where M, N are the size of the image. Finally, the correctness of the keystream recover algotithm is verified by experiments.