摘要
针对传统的图像加密算法,加密策略与待加密图像无关且对像素的置换和混淆往往被拆分为两个耦合性较低的孤立环节所带来的安全问题,提出基于约瑟夫遍历和广义Henon映射的图像比特位加密算法,将待加密图像安全哈希算法1(SHA-1)摘要和用户选定的加密参数联合作为密钥,驱动广义Henon映射对改进的用于位点置换的约瑟夫遍历映射的起始位置、报数间隔和报数方向进行随机扰动,从而使不同的加密图像和加密参数实质对应于不同的位点置换过程,并添加了位点混淆过程以提高位点置换的安全性。实验表明,所提算法可有效地抵抗选择性明文攻击,具有较大的密钥空间和较好的加密性能。
In conventional image encryption algorithms,pixel permutation and diffusion are always two loosely coupled isolated stages and the encryption strategy is usually irrelevant to plaintext image,which brings security risks. To address these problems,this paper proposed a bit-level image encryption algorithm based on Josephus traversing and generalized Henon chaotic map,where Henon map variables combined with the secure hash algorithm 1（ SHA-1） digest of plaintext image as the key to drive Henon map producing modified Josephus traversing map＇s start point,number space and number direction variables.It used the generated Josephus traversing map variables to permutated plaintext image＇s pixel bits where mapped different plaintext image and key to different bit permutation stage. To improve security,the proposed method added pixel bits diffusion stage. Experiments show the proposed algorithm can effectively resist the selective plaintext attack,it has a large key generating space and a good encryption performance.
出处
《计算机应用研究》
CSCD
北大核心
2015年第4期1131-1137,共7页
Application Research of Computers
基金
国家自然科学基金资助项目(61100239)
国家教育部高等学校博士学科点专项科研基金资助项目(20110202120002)
陕西省科技新星计划资助项目(2011kjxx17)
陕西省自然科学基金资助项目(2011JQ8009)
中央高校基本科研业务费支持项目(GK201402036)
