【作者】 杨彬；

【导师】 吕锋；

【作者基本信息】 武汉理工大学 ， 通信与信息系统， 2006， 硕士

【摘要】 随着信息技术的发展,信息安全问题越来越受到人们的重视。信息隐藏技术是一门将秘密信息隐藏在非秘密信息(例如音频、视频、静止图像以及文本)当中,从而不引起人们对信息隐藏载体的感知的改变。近几年,信息隐藏技术的发展迅猛,人们提出了许多信息隐藏的方法和算法。现在信息隐藏技术已经广泛的应用于多媒体信息的版权保护及信息安全等领域。 随着信息隐藏技术的发展,人们提出了各种各样的信息隐藏的方法和方案。从隐藏技术上分类,大多可以分为空间域和变换域的方法。空间域算法简便,信息隐藏量大,但是算法的鲁棒性差,隐藏信息很容易为滤波、图像量化、几何变形的操作破坏。变换域算法,有较强的抗攻击能力,但是该类算法的隐藏和提取信息操作复杂,隐藏信息量不能很大。 本文对信息隐藏技术的算法和应用进行了研究,提出了一种基于图像分割和小波变换的信息隐藏算法。主要工作如下: (1)研究了信息隐藏技术的基本特征、一般原理以及国内外的研究现状,包括信息隐藏技术的分类、归纳了信息隐藏系统的基本框架,概括性了解了目前常见的信息隐藏算法。并学习了小波变换的定义、连续小波变换、离散小波变换。 (2)根据空间域和小波域的特点,提出了一种基于图像分割和小波变换的信息隐藏算法。首先对被隐藏图像进行Arnold置乱,把主图像划分为n×n区域,对每个区域进行三次离散小波变换,再利用算法把待隐藏信息嵌入各个区域的中频子带和高频子带,实施多处信息隐藏以提高其鲁棒性。 (3)对提出的算法进行了仿真实验,并对嵌入信息的图像进行各种攻击测试。虽然攻击测试处理后相关系数值有所下降,但是仍能检测出水印。实验表明,该算法对嵌入信息具有不可见性和良好的鲁棒性。更多还原

【Abstract】 Following with development of information technology, information security receives more and more emphases. Information hiding technology can hide secret information in the non-secret information (such as audio, video, static graphics and text) thus people will have no sense with the change about the information hiding carrier. In recent years, information hiding technology has a high speed development, people proposes many information hiding method and algorithm. Now information hiding technology has already had widespread application in multimedia information copyright protection and information security etc..Along with development of information hiding technology, people proposed various information hiding method and plan. Classifies by hiding technique, these methods may divide into spatial domain and transform domain method. Spatial domain algorithm is simple and can hide amount of information but algorithm robustness is bad, the secret message can be very easily destroyed by the filter, the image quantification, the transforming geometry. Transform domain algorithm has the strong anti- attack capability, but this kind of algorithm has more complex operations on hiding and withdrawing information, so the quantity of the secret information cannot be very big.This paper researches the algorithm and application of information hiding, the algorithm of information hiding based on picture division and wavelet transformation, information hiding algorithm was proposed. The works are following:(1) Research the essential feature, principle and present domestic and international research current situation of information hiding., including classification of the information hiding, have summed up the basic frame of the information hiding system. Generality has learned the common information hiding algorithm at present. And study Wavelet Transform definition, Continue Wavelet Transform and Discrete Wavelet Transform.(2) According to the characteristic of spatial domain and wavelet domain, the algorithm of information hiding based on picture division and wavelet transformation information hiding algorithm was proposed. First, a hidden picture is Arnoldtransformed,the main picture is divided into n X n regions in which discrete wavelet transformation is used for three times. Then the hiding information is embedded into the middle frequency sub-band and the high frequency sub-band in every region by using algorithm, the robustness can be increased by using information hiding in places.(3) According to the algorithm the simulation experiment is carried out, and the picture embedded information undergoes various attacking testing .The corresponding modulus has fallen down , but the watermark still can be detected. The experiment shows that the embedded information has invisibility and fair robustness.更多还原