基于细胞神经网络加密的小波域数字图像隐藏.pdf

河北大学
硕士学位论文
基于细胞神经网络加密的小波域数字图像隐藏
姓名:赵志广
申请学位级别:硕士
专业:通信与信息系统
指导教师:郑伟
2011-03
摘要
摘要
随着网络的日益普及,信息的交流达到了前所未有的深度和广度。其中涉及军事、
政治和商业机密的敏感信息也通过公开的网络进行传输并需要得到有效的保护,于是就
催生了服务于隐蔽通信和产权保护的新兴学科---信息隐藏学。
数字图像形象直观、信息量大和便于计算的特点决定了其逐渐成为信息隐藏技术的
一个重要应用领域。目前的图像隐藏技术主要由预处理算法、隐藏嵌入算法和提取算法
构成,其中的预处理算法主要是对原始秘密图像进行加密处理,目的是提高整个系统的
安全性。传统的混沌加密系统的动力特性相对简单、确定序列的参数少、密钥简单、安
全性不高,这些缺陷决定了低维混沌序列的保密性是不够的。
本文利用五阶细胞神经网络产生敏感性和复杂性更高的超混沌序列,经过量化编码
后转换成二值超混沌加密序列,再结合阿诺德置乱加密算法,提出一种优化了的细胞神
经网络加密算法。利用图像低位平面近似随机噪声的特点,提出一种基于位平面补偿机
制的小波域隐藏嵌入算法,即在嵌入算法中只嵌入经细胞神经网络加密算法处理过的四
个高位平面,当接收方恢复秘密图像时随机选取一幅跟秘密图像一样大小的灰度图像的
四个低位平面进行补偿,进而恢复出原始秘密图像,实验证明该算法通过降低隐藏容量
大大提高了算法的不可见性,同时保持了较高的鲁棒性。

关键词图像隐藏小波变换细胞神经网络超混沌鲁棒性







I
Abstract
Abstract
As work is ing more and more popular today, the exchange of information
has got to an unprecedented depth and breadth. The sensitive information involving military,
political mercial confidentiality is also transmitted through the work, and it
also needs protection. Then the information hiding technology is produced to serve the
munication and the protection of property rights.
The information hiding technolgy is mainly used in the image hiding domain for the
three advantages, which are intuitive imgae, large amount of information and convenience for
caculation. The current image hiding technique is mainly made up of the preprocessing
algorithm, embedding algorithm and extraction. The preprocessing algorithm is used to
encrypt the original secret image in order to improve the security of the entire system. The
traditional chaotic encryption system has many disadvantages, like relatively simple dynamic
characteristics, few of parameters, simple keys and low security, which determine the
confidentiality of the chaotic sequence is not enough.
The fifth-order cellular work (CNN) is used to produce highly sensitive and
complicated hyperchaotic sequences, which are quantizated and coded into binary
hyperchaotic se