替代和置乱相结合的图像分块加密算法  

Image Block Encryption Algorithm Based on Substitution and Scrambling

作　　者：李娟[1] 

机构地区：[1]内蒙古化工职业学院计算机与信息工程系,内蒙古呼和浩特010070

出　　处：《自动化仪表》2014年第3期55-59,共5页Process Automation Instrumentation

基　　金：内蒙古化工职业学院基金资助项目(编号:ZJY0708C;KY200903)

摘　　要：为增强数字图像的安全性,提出了一种基于替代和置乱的图像分块加密算法。首先将原图像分块,并对每个图像块内像素点执行按位替代操作;然后利用均匀分块置乱算法,将各个图像块内像素完全扩散到其他图像块中;接着利用Fibonacci算法对每个图像块进行像素值置乱;最后采用Fibonacci算法对整幅图像做像素位置置乱,以消除图像的空间相关性。试验结果表明,该算法可以有效地对图像进行加密解密,可有效抵抗不同程度的剪切和噪声攻击,且实时性较好。To strengthen the security of digital images, the image block encryption algorithm based on substitution and scrambling is proposed. Firstly, the original image is divided into sub-blocks, and bitwise substitute operation is executed for each pixel in image block; then by adopting uniform sub-block scrambling algorithm, each pixel in image block is fully diffused to other image blocks, and pixel value is scrambled for each image block by using Fibonacci algorithm;finally, pixel position scrambling is conducted for the whole image using Fibonacci algorithm to eliminate spatial correlation of the image. The experimental results indicate that this algorithm can effectively doing encryption and decryption for images, it is able to effectively resist attacks of shears and noises, and offers better real time performance.

关 键 词：图像安全 图像加密 置乱 FIBONACCI变换 均匀分块 

分 类 号：TP311[自动化与计算机技术—计算机软件与理论]