基于有限状态斜帐篷映射的图像加密算法

An Image Encryption Approach Based on Finite States Skew Tent Map

针对图像加密算法中迭代性高、低维离散混沌加密密钥空间小、保密性低等特点,提出了一种基于有限状态斜帐篷映射的混沌加密方法.该方法采用一种有限状态skew tent映射来产生伪随机整数序列,然后依据该混沌序列控制图像像素的置换和灰度值的修改.攻击者在不知道密钥的情况下,加密图像不能被正确重建.并对图像加密算法的安全性从统计角度进行了分析,计算结果表明密文图像的直方图趋于均衡一致,密文图像在水平、垂直和对角线方向上像素的相关性显著降低.

It is well known that image encryption algorithm is of high iteration,low-key encryption-dimensional discrete chaotic space and low privacy.A finite state skew tent map is presented to generate pseudo-random integer number sequences based on the key.According to the discrete sequences,gray value of image pixel is modified randomly,it is obvious that if an attacker does not know the key,the encrypted image will be looked like white noise and cannot be rebuilt.The proposed algorithm is described in detail,based on its security analysis and implementations.Experimental results demonstrate that correlation of cipher image pixel in horizontal,vertical and diagonal directions decrease obviously,and the presented algorithm can also resist chosen/known plaintext attack and ciphered image damage attack.