基于Gray变换的图像置乱改进新算法

摘要

This paper proposes a new improved image scrambling algorithm based on gray transform.Firstly the algorithm does gray transform for original image, then Zig-Zag scan can be used, furthermore, making a bit-exclusive-or operation on each pixel with prior one, and the bits of each pixel value are exchanged across.thereby the ability of resisting decoding or attacking is improved again.The experimental results show that compared with some existing algorithms, the method not only provides with a scrambling image whose histogram has been changed obviously, but also the scrambled image look more like Gaussian noise, which is experted when being applied into the image encryption transmission or the preprocessing of secret images in digital watermarking.%文章提出了一种基于Gray变换的图像置乱改进新算法,首先对原始图像进行Gray变换,然后对变换后的图像进行Zig-Zag扫描,再对每个像素值和它前面相邻的像素值进行按位异或运算,同时对运算的结果进行像素值的交叉换位,提高抵抗破译攻击的能力.实验结果表明,该算法与传统的图像置乱算法相比,置乱后的图像不仅直方图发生了显著改变,而且置乱图像的统计特征更像白噪声,更加适用于图像文件的加密传输和秘密图像信息置乱预处理.