基于置乱、混淆与掩蔽规则融合3D混沌映射的图像加密算法研究

针对当前的3D混沌映射加密算法存在安全性不高,加密速度慢、密钥空间小以及不具备抗多种攻击能力等不足,设计了三个规则:置乱规则、混淆规则与掩蔽规则,提出了一种基于置乱、混淆与掩蔽三规则融合3D混沌映射的图像加密算法来解决上述问题。首先对初始图像的字节进行预置乱处理,得到位图图像;随后将其分成若干个小块,在置乱规则下迭代3D混沌映射得到一个二维数组,利用该数组选择像素块进行像素位置置乱操作;在混淆规则下迭代3D混沌映射得到一维伪随机数组,利用该数组对置乱后的像素块进行混淆操作;在掩蔽规则下再次迭代3D混沌映射得到三元序列,利用该序列对扩散后的像素块进行掩蔽处理。在MATLAB仿真软件中验证本文算法,结果显示该算法高度安全,密钥空间巨大,运行速度快。

The Study on Image Encryption Algorithm Based on 3D Chaotic Map Integration with Permutation, Mixing and Masking Rule

To these lacks of image encryption of current 3D chaotic map such as low security, low encryption speed, small key space and not having the ability for resisting multi-attacks, the three rules, including permutation rule, mixing rule and masking rule were designing, and the new image encryption algorithm based on 3D chaotic map integration with permutation, mixing and masking rule was proposed to solve above defects. Firstly, the advance permutation of bytes from the original image was started to get the bitmap; Then the bitmap was separated into several blocks, the array was obtained by iterating the 3D chaotic map under the shuffled rule, and the array was used to choose blocks to permute the pixel position; Secondly, a pseudo-random numbers was obtained by iterating the 3D chaotic map under the mixing rule to mixing the pixel value of the permutation image; Finally, the sequence of triples of numbers was got by iterating the 3D chaotic map under the masking rule to mask the encryption blocks. The MATLAB simulation software was used to validate the encryption algorithm proposed by this paper, the results showed that: this image encryption algorithm has a good encryption property such as highly secure, huge key space, and fast encryption speed.