基于NCA的数字图像分块加密算法

A Blocking Algorithm of Digital Image Encryption Based on NCA

提出了一种基于改进的Logistic混沌序列(NCA)的彩色图像分块加密算法,分别对图像的R、G、B分量进行了分块置乱,摆脱了NCA用于像素加密时对迭代数的限制,然后通过取迭代值有效数字的方法生成异或序列进行像素置换。Matlab 7.0仿真结果表明,该算法具有密钥空间大、对初值敏感以及良好的实时特性,能够保证互联网中保存的数字图像的安全。

A blocking algorithm of digital color image encryption based on improved Logistic chaos sequence（NCA） is presented in this paper, the sub-block of R,G,B components are scrambled respectively. The new algorithm gets rid of restrictions on iterations of NCA. We use the significant figures of iteration value to be the matrix to replace the pixel value. The simulation results used by Matlab 7.0 show that the new algorithm has good advantages such as a larger key space, sensitive to initial conditions and better real-time characteristic, so it can protect the images security over the internet.