摘要

Based on the permutation-diffusion architecture, this paper introduces a more sensitive chaotic image encryption scheme using breadth-first search and dynamic diffusion to enhance the security and sensitivity. In the permutation stage, the plain image is traversed by breadth-first search, and then the whole permutation is performed to obtain a shuffled sequence. Similarly, the diffusion key stream is rearranged by breadth-first search. Moreover, a dynamic diffusion method is proposed to encrypt the shuffled sequence in the diffusion stage, which can ensure that encrypting each pixel is related to all other pixels and can enhance the sensitivity of the cryptosystem. In each phase, the hyper-chaotic system in this scheme generates pseudorandom sequences. The simulation results and performance analysis show that the proposed scheme has excellent performances and high security in resisting brute-force attack, statistical attack and differential attack.