基于L-K双混沌系统的彩色位级图像加密算法

COLOR BIT-LEVEL IMAGE ENCRYPTION ALGORITHM BASED ON L-K DOUBLE CHAOTIC SYSTEM

针对传统加密算法精度有限、安全性低等问题,提出一种新的彩色图像加密算法。利用Liu混沌系统产生的混沌序列对彩色图像R、G、B三层的低五位进行索引位置置乱,再对高三位进行Arnold置乱;采用自适应方式进行扩散,并将R、G、B三层的密文图像循环异或,得到初步密文图像;联合像素级加密进行Hilbert置乱,采用Kawakami超混沌结合图像信息进行分形扩散,得到最终密文图像。仿真实验表明,该算法NPCR和UACI达到99.78%和33.37%,信息熵为7.9970,安全性很高。

Aiming at the problems of limited precision and low security of traditional encryption algorithms,we propose a new color image encryption algorithm.The chaotic sequence generated by the Liu chaotic system was used to scramble the lower five bits of the three layers of the color image R,G,and B,and then Arnold was scrambled for the upper three bits.Then we adopted an adaptive method to perform diffusion,and cycled the R,G and B ciphertext images to obtain the preliminary ciphertext images.Finally,Hilbert scrambling was performed by combining pixel-level encryption,and the Kawakami hyperchaos was combined with the image information for fractal diffusion to obtain the final ciphertext image.Simulation experiments show that the NPCR and UACI of the algorithm reach 99.78%and 33.37%,and the information entropy is 7.9970,and its security is very high.