一个可用于完整性确认的数字图像水印算法

首先提出了一种鲁棒的、公开水印新算法,然后采用该新算法和LSB这两个不同的算法,在同一个载体图像中,同时加入了两个同样的自相似水印,一个是完全脆弱的水印,另一个则是鲁棒的水印.采用这种双重水印嵌入方案,通过对这两个分别是完全脆弱和鲁棒的水印的提取,并通过它们之间的对比和互相验证,可以达到鉴别对图像的篡改,以及对篡改的位置和篡改的内容进行识别,进而达到完整性确认的目的.     

基于颜色分量选取的彩色图像数字双水印算法研究

针对彩色图像版权保护和完整性认证问题,提出了一种基于颜色分量选取的彩色图像数字双水印算法。水印嵌入前对DCT系数进行量化,并在DCT分块中频系数中嵌入用于版权保护的鲁棒水印,在低频系数中嵌入用于检测篡改的半脆弱水印。仿真实验表明,该算法能较好地标示版权和检测篡改。     

基于DCT和混沌的双重图像水印算法

为实现图像版权和完整性认证,提出一种基于DCT和混沌的双重水印算法。对图像进行DCT分块,在低频部分利用SVD方法嵌入鲁棒水印,在高频部分用系数大小关系嵌入脆弱水印,从而实现了盲检测。仿真实验结果表明,由于鲁棒水印具有一定的抗JPEG能力,脆弱水印能抵抗较强的噪声攻击,因此该算法是有效的。     

基于DCT域的数字图像双水印算法

提出了一种基于DCT域的数字图像双水印算法,将鲁棒水印与脆弱水印同时嵌入到DCT的中低频系数中,鲁棒水印和脆弱水印的嵌入与顺序无关,且不相互影响.首先,对DCT变换后的系数按照它们的位置进行了特殊的分类,通过分类后每一类中正负号的数量来表达鲁棒水印信息,增强了算法的鲁棒性.对相同的DCT 系数使用邻近值比较法嵌入脆弱水印.实验结果表明鲁棒水印可以实现了对图像载体的版权认证,脆弱水印实现了对图像载体的完整性保护和篡改定位.     

基于DWT和SUDOKU的多功能数字图像水印算法

传统的水印算法一般都是单功能的,在实用中很难满足,为了实现对数字图像的双重保护,提出了一种基于DWT和数独SUDOKU的多功能鲁棒-脆弱数字图像水印算法。首先,通过修改图像子块的小波域系数的值,将鲁棒水印嵌入到数字图像中以实现数字图像的版权保护功能。然后,基于数独模型,将脆弱水印信息嵌入到图像空域中以实现数字图像的篡改定位功能。仿真实验结果表明,该多功能数字图像水印算法把鲁棒水印和脆弱水印有效的统一起来,嵌入两种水印后的数字图像具有良好的不可见性,提取的鲁棒水印具有较强的抗攻击能力,而脆弱水印则能准确定位出篡改位置。     

基于支持向量机和混沌序列的空域图像双水印

为解决图像同时具有版权保护和内容认证需求问题,提出了一种基于支持向量机的鲁棒水印和混沌序列与LSB相结合的脆弱水印的双重图像水印算法.利用图像邻域像素之间的相关性,通过训练回归型支持向量机模型实现鲁棒水印图像嵌入或提取操作.然后,再将已嵌入鲁棒水印的载体图像用最低有效位和混沌序列相结合的方法嵌入基于载体图像内容的脆弱水印.实验结果表明,该算法同时实现了图像的版权保护和内容篡改定位,提高了水印系统的安全性.     

一种新颖的复合型盲水印算法

针对很多数字水印设计方案都是单水印嵌入的状况,提出了一种新的复合型图像水印技术。在图像作品里同时嵌入鲁棒水印和脆弱水印。这样,既对图像作品进行了版权保护,又能知道作品内容是否被篡改,实现了版权保护和内容认证的双重功能。两种水印的提取和检测工作都不需要原始图像就可以完成,是一种盲水印算法。仿真实验表明,该算法比较有效,具有很好的应用前景。     

一种基于DCT的彩色图像双水印算法

提出了一种用于版权保护和完整性认证的彩色图像双水印算法。基于YCbCr颜色空间,将原始图像各个分量进行分块,在各分量图像子块DCT域中直流系数上嵌入鲁棒水印以标示版权;在亮度分量的中频系数上嵌入抗JPEG压缩的半脆弱水印以进行篡改检测和篡改定位。仿真实验表明该算法能够很好地标示版权和检测篡改。     

基于混沌的DWT域多功能图像数字水印算法

提出了一种基于混沌的DWT域多功能图像数字水印算法。原始水印分为鲁棒水印和半脆弱水印,分别用于版权保护和图像认证。根据不同的应用,鲁棒水印又分为容量小但鲁棒性要求相对高和容量大但鲁棒性要求相对低的两种,它们和半脆弱水印分别嵌入DWT域的不同部分。并利用广义猫映射置乱鲁棒水印和Logistic混沌系统生成半脆弱水印以提高安全性。实验表明,嵌入水印后的图像视觉质量好,其中鲁棒水印能抵抗各种常规图像处理,半脆弱水印能准确地检测并定位内容篡改。     

基于标记矢量量化的多重音频数字水印算法

提出一种基于矢量量化和DCT变换的多重音频数字水印算法.该算法将鲁棒水印和脆弱水印分别嵌入到载体音频信号中,同时完成版权保护和音频内容完整性认证的功能.鲁棒水印在进行码字标记的矢量量化过程中嵌入到DCT中频系数中,脆弱水印采用索引约束的方法嵌入到DCT高频系数中.鲁棒水印和脆弱水印都能实现盲提取.实验结果表明,本算法引...     

Fragile watermarking for authenticating 3-D polygonal meshes

Designing a powerful fragile watermarking technique for authenticating three-dimensional (3-D) polygonal meshes is a very difficult task. Yeo and Yeung were first to propose a fragile watermarking method to perform authentication of 3-D polygonal meshes. Although their method can authenticate the integrity of 3-D polygonal meshes, it cannot be used for localization of changes. In addition, it is unable to distinguish malicious attacks from incidental data processings. In this paper, we trade off the causality problem in Yeo and Yeung's method for a new fragile watermarking scheme. The proposed scheme can not only achieve localization of malicious modifications in visual inspection, but also is immune to certain incidental data processings (such as quantization of vertex coordinates and vertex reordering). During the process of watermark embedding, a local mesh parameterization approach is employed to perturb the coordinates of invalid vertices while cautiously maintaining the visual appearance of the original model. Since the proposed embedding method is independent of the order of vertices, the hidden watermark is immune to some attacks, such as vertex reordering. In addition, the proposed method can be used to perform region-based tampering detection. The experimental results have shown that the proposed fragile watermarking scheme is indeed powerful.     

A public fragile watermarking scheme for 3D model authentication

A public fragile watermarking scheme based on the sensitivity of vertex geometry is proposed for 3D model authentication. In the 3D fragile watermarking embedding, slightly perturbing the positions of a subset of vertices is usually needed to keep them in some predefined relationship with their neighboring vertices. Two problems frequently arise in the embedding stage: the causality problem and the convergence problem. The causality problem arises while the neighboring relationship of a former processed vertex is influenced by the perturbing of its latter processed neighboring vertices. The convergence problem means that the original model has been heavily distorted before some vertices reach the predefined relationship. In this paper, we propose a multi-function vertex embedding method and an adjusting-vertex method to overcome these two problems. The proposed method does not need the original model and watermarks for authentication; moreover, the key for extracting watermarks is relatively smaller than that of previous works. For some artistic or technical models, sometimes it is very important to control the distortion ratio caused by watermark embedding. Our method can control the average distortion by the keys used in watermark embedding. Experimental and analytic results on various kinds of 3D models show the effectiveness of the scheme.     

复合式的多功能数字水印算法

提出了一种鲁棒性数字水印和脆弱性数字水印相结合的复合式水印算法,具有较好的双重保护性能,即鲁棒性数字水印用于版权认证方面和脆弱性数字水印用于图像内容的保护.首先,在原始载体图像的DCT中频域上嵌入不可见水印;其次,再根据LSB算法在空域自适应地嵌入脆弱性数字水印.实验结果表明,该方法不可见性好,对一般的图像处理和攻击,如JPEG压缩、滤波、加噪声、旋转、缩放等都有良好的鲁棒性,同时还能对图像中细微的篡改进行有效精确的定位,并且作为一种盲水印算法有着良好的安全性.     

基于证据理论数据融合的双效水印

提出一种新的基于证据理论的数据融合的双效水印算法.首先应用水印公式构造特殊的水印嵌入后条件,根据嵌入系数之间的定性分析提取鲁棒水印;利用嵌入系数之间的定量分析能提取脆弱水印,并能准确定位篡改的区域.其次在嵌入过程中还使用纠错码对水印信息进行调和,把水印重复嵌入到图像信息的不同位置,以便利用纠错码的辅助信息来估计出提取的...     

一种易损性音频数字水印技术

利用变换域嵌入水印是音频水印的主流技术,一般的嵌入方法是通过调整所选变换系数实现。谱弯折方法实现整段频谱的非线性位移,可将水印嵌入整个频谱。该文在Choi犤1犦的谱弯折音频数字水印算法基础上,研究了算法的鲁棒性,通过大量实验验证,认为谱弯折算法对信号处理类攻击相当脆弱,不具备鲁棒性,是一种易损性音频水印。     

易损数字水印技术：研究与应用

1.引言随着数字化和网络化的发展,出现了数字多媒体的版权和完整性保护等问题。为了解决这些问题,人们开始做各方面的研究,而数字水印技术是其中的一个主要研究方向,并且得到了越来越多的关注。当前研究的数字水印,按其特性主要可以分为两类:鲁棒数字水印和易损数字水印。鲁棒数字水印(Robust Watermarking),要求对多媒体数据进行操作时,不会或者很难去除或破坏嵌在数据中的数字水印,也就是要求保证水印的鲁棒性。主要用于数字产品的版权保护,比如在数字作品中表示著作权信息,如作者、作品序号等,它要求嵌入     

基于脆弱性数字水印的图象完整性验证研究

计算机网络技术的飞速发展与信息媒体的数字化 ,使得在网络环境中对数字产品实施有效的内容保护成为一个迫在眉睫的现实问题 .传统的数字签名技术只是用于对通信领域的信息传送进行篡改检测 ,而脆弱性数字水印技术则为网络环境下多媒体的内容保护提供了一个有效的解决方案 .与鲁棒性水印不同的是 ,脆弱性水印主要用于检测发生在多媒体数据中的篡改 ,并对其定位 .为了推动我国在此前沿领域研究工作的进一步深入 ,这里就当前脆弱性数字图象图象水印技术的基本特征、一般原理、研究现状、攻击方法及发展方向进行一个综述 .     

基于特征的易碎图像水印框架

提出了一种基于特征的易碎图像水印框架,来阻止VQ攻击.图像特征被提取出来,用 来处理原始水印或生成水印,使得要嵌入的水印信息不仅不被攻击者知道,而且依赖于原始图 像.因此,不同的原始图像嵌入了不同的水印信息,从而使得攻击者无法建立VQ码表,因而无法 实现VQ攻击.同时,为了提高水印的安全性和篡改的局部检测性,本文给出了该框架下水印嵌 入方法的基本要求.根据该易碎图像水印框架,本文设计了一种基于图像矩不变量的易碎水印算 法.分析和实验结果表明,该算法不仅可以很好地、局部地检测图像中的篡改.即使图像中仅有一 位被篡改时.同时,在不需任何额外的密码或图像索引号的情况下,成功地抵抗VQ攻击.     

Hierarchical Watermarking of Semiregular Meshes Based on Wavelet Transform

This paper presents a hierarchical watermarking framework for semiregular meshes. Three blind watermarks are inserted in a semiregular mesh with different purposes: a geometrically robust watermark for copyright protection, a high-capacity watermark for carrying a large amount of auxiliary information, and a fragile watermark for content authentication. The proposed framework is based on wavelet transform of the semiregular mesh. More precisely, the three watermarks are inserted in different appropriate resolution levels obtained by wavelet decomposition of the mesh: the robust watermark is inserted by modifying the norms of the wavelet coefficient vectors associated with the lowest resolution level; the fragile watermark is embedded in the high resolution level obtained just after one wavelet decomposition by modifying the orientations and norms of the wavelet coefficient vectors; the high-capacity watermark is inserted in one or several intermediate levels by considering groups of wavelet coefficient vector norms as watermarking primitives. Experimental results demonstrate the effectiveness of the proposed framework: the robust watermark is able to resist all common geometric attacks even with a relatively strong amplitude; the fragile watermark is robust to content-preserving operations, while being sensitive to other attacks of which it can also provide the precise location; the payload of the high-capacity watermark increases rapidly along with the number of watermarking primitives.      

VRML animated model watermarking scheme using geometry and interpolator nodes

Distinct from image and video watermarking, a watermarking scheme for 3D animation content is required in the 3D industry market for various applications. This paper develops a watermarking scheme for copyright protection and authentication of 3D animation content. A 3D animated model generally has a hierarchical structure with a number of transform nodes of a geometry node and an interpolator node for the timeline in contrast to a 3D polygon mesh model. The proposed scheme embeds not only a robust watermark into the geometry node for copyright protection but also a fragile watermark into the position and orientation interpolators for content authentication. We named the former “robust geometry watermarking” and the latter “fragile interpolator watermarking”. The proposed scheme performs the two watermarking schemes independently to realize simultaneously robust and fragile watermarked 3D animated model. Experimental results confirm that a watermark embedded by geometry watermarking robust to many attacks from commercial 3D editing tools while a watermark embedded by interpolator watermarking fragile to the same attacks.