基于单图像局部置乱和动态反馈扩散的混沌图像加密算法

Chaotic image encryption algorithm based on single image local scrambling and dynamic feedback diffusion

提出一种基于单图像局部置乱和动态反馈的混沌图像加密算法。首先,提出一种单图像局部置乱算法。其次,在扩散阶段,采用一种基于动态反馈的扩散策略来改变置乱后图像中的像素值,通过动态反馈来改善图像的加密效果。最后,实验结果表明,与3种经典的算法相比,提出的算法大大缩短了加密时间;并且只通过一次加密,其像素变化率和归一化平均变化强度值都可接近99.6%和33.4%,进一步证明了提出的算法具有良好的抵抗差分攻击的能力。

A novel chaotic image encryption algorithm based on single image local scrambling and dynamic feedback diffusion was presented. Firstly, a single image local scrambling algorithm was proposed. Secondly, a novel dynamic feedback diffusion strategy was proposed to change the pixel values of the scrambled image in the phase of diffusion, by which improved the results of image encryption. Finally, the simulation results and performance analysis show that the number pixels change rate（NPCR） values and unified average changing intensity（UACI） values of the proposed algorithm can be close to 99.6% and 33.4%, showing that the proposed algorithm has better resistance to differential attacks and saves time compared with the other three classic algorithms.