基于二维CA和CWQ方法的图像加密方案(英文)

A New Image Encryption Scheme Based on Two-Dimensional CA Joint With CWQ Method

细胞自动机简称CA,是具有离散的空间和时间特性的动力系统.在过去的10多年里,细胞自动机在密码系统和信息安全方面的应用得到了人们相当大的关注和兴趣.本文给出了一种结合格图结构摩尔邻域的二维CA方法和基于四叉树结构的CWQ方法的图像加密方案.首先,二维CA的加密方法可以比仅进行混淆作用的CWQ方法更有效地提高系统的安全性.其次,CWQ方法可以加强具有雪崩效应和扩散性质的二维CA方法的混淆性质.方案具有大密钥量且简单易行适用于数字图像加密等特点.

CA is the abbreviation of cellular automata which are dynamical systems with discrete space and time. Considerable interest has been shown over the past decade in the use of cellular automata in cryptography. The aim of this paper is to present a new scheme for image encryption, which combines two-dimensional CA approach we proposed in Moore neighborhood on the graph structure of square lattice and CWQ method based on quad-tree structure. First, the two-dimensional CA encryption approach can strengthen the system＇ s security more greatly than the confusion-only CWQ method. Second, CWQ method enhances the confusion property of the two-dimenslonal CA approach which satisfies avalanche effect and the property of diffusion. Moreover, an important feature of the proposed scheme is that it has very large number of security keys and simple operations which are especially useful for digital image encryption.