阵列噪声增强技术在数字信息隐藏中的应用研究  

Study of Application of Array-noise-enhanced Technology to Digital Information Hiding

作　　者：袁莉莉[1] 徐小龙[1] 段法兵[1] 

机构地区：[1]青岛大学复杂性科学研究所,山东青岛266071

出　　处：《复杂系统与复杂性科学》2008年第1期73-80,共8页Complex Systems and Complexity Science

基　　金：国家自然科学基金(60602040);教育部博士点联合资助基金(20051065002)

摘　　要：研究了阵列噪声增强技术在数字信息隐藏中应用。非耦合的双稳态检测器组成的并联阵列可视为一种规则网络,阵列噪声与检测器参数都是可调谐参数,网络输出性能能够由非零阵列噪声优化。这就是阵列随机共振现象,也可以视为一种阵列噪声增强技术。将代表版权等信息的黑白字符水印排列成二进制序列之后,依据非线性双稳态检测器的频率检测鲁棒性,将之调制成具有一定延迟时间的脉冲调幅信号。宿主图像经离散余弦变换(DCT)后,在中频区域中选相应数量的DCT系数经Arnold变换置乱后作为背景噪声,水印信号则嵌入这些选定的中频系数中。嵌入水印的DCT系数经过逆变换后得到水印图像。水印图像受到各种信号处理方法的攻击时,可以利用非线性双稳态检测器从攻击图像中提取水印字符。通过阵列噪声增强技术,提取水印和原始水印字符的相似度与单独的双稳态检测器检测结果相比得到了进一步改善。A DCT-domain watermarking scheme, based on array-noise-enhanced technology, is presented in this paper. A regular network, i.e. an uncoupled parallel array of bistable detectors, can be optimized by non-zero array noise as well as detector parameters. This is the effect of array stochastic resonance, or named by array-noise-enhanced technology. In this paper, a binary copyright character representing copyright is reordered into a binary sequence, and then mapped into the pulse-amplitude-modulated signal. Certain desyn-chronization time can be arbitrarily placed into one or some codes of the modulated signal, and will be tolerated due to the robust superiority of nonlinear detectors. A host image is transformed into frequency domain by discrete cosine transform （DCT）. The watermarking signal is then embedded in a selected set of medium-frequency DCT coefficients shuffled by Arnold transform, which then looks more like background noise for the watermark signal. Some common attacks are considered in experiments. Given various attacked images, the corrupted watermark is extracted by nonlinear bitable detectors. Interestingly, higher similarity between the original character and the extracted one can be further achieved by a parallel array of bistable detectors via the noise-enhanced technology. The present scheme and related results extend the application of complex random systems to information processing.

关 键 词：阵列噪声增强技术 双稳态检测器 ARNOLD变换 数字信息隐藏 

分 类 号：N945.12[自然科学总论—系统科学] TP391[自动化与计算机技术—计算机应用技术]