基于填充曲线和相邻像素比特置乱的图像加密方法

为提高图像传输安全性,该文提出一种基于填充曲线和相邻像素比特置乱的加密算法.首先,设计一种新的填充曲线用于图像像素的全局置乱.其次,将混沌序列作为约瑟夫遍历的起点和步长,利用改进的约瑟夫遍历方法对相邻像素进行比特级置乱.像素级和比特级的双重置换,打破了图像像素间的高度相关性.最后,通过双向密文反馈,进一步提高方法的安全...

An Image Encryption Algorithm Based on Filling Curve and Adjacent Pixel Bit Scrambling

To improve the security of image transmission, an encryption algorithm based on filling curve and adjacent pixel bit scrambling is proposed. Firstly, a new filling curve is designed and used to scramble image pixels globally. Secondly, the chaotic sequences are taken as the starting point and step length of Josephus traversal, and the adjacent pixels are bit scrambled by the improved Josephus traversal method. Through double scrambling, the high correlation between pixels of the plain image is broken. Finally, the security of the method is further improved by two-way ciphertext feedback. In addition, an adaptive key generation method associated with the plain image is designed to overcome the chosen/known-plaintext attack. The proposed scheme is analyzed from the aspects of key-space, key sensitivity, information entropy and correlations. The results show that this algorithm has good performance and sufficient security.