一种改进的混编视频水印方案

提出了一种具有鲁棒性和脆弱性的改进混编视频水印方案:将鲁棒性和脆弱性水印分别嵌入到DCT宏块的中频交流系数和运动矢量的水平分量中,实现了秘密信息及验证信息在视频中的隐藏,具有版权保护和视频完整性认证的能力.实验结果表明,与G.Qiu等提出的混编视频水印方案相比,该方案在鲁棒性水印嵌入时,码率增幅平均降低6％,有更好的抗攻击能力;脆弱性水印对攻击的敏感性更高.     

基于DWT和DCT的视频数字双水印方法

针对单水印算法存在功能单一的问题,提出一种基于DWT和DCT的视频数字双水印方法,通过嵌入鲁棒性水印和脆弱性水印实现视频版权和完整性认证的双重目的。利用DWT和DCT变换、多重嵌入等方法,在同一视频序列中先后嵌入两种不同类型的数字水印,后嵌入的脆弱性水印服务于先嵌入的鲁棒性水印。实验结果表明,该方法不仅能有效地保护视频信息的版权,还能抵抗一些常见攻击,以达到防止被篡改的目的,具有较好的鲁棒性和不可见性。     

一种强鲁棒性的视频水印方案

根据MPEG-4视频压缩原理,提出一种基于DCT(discrete cosine transform离散余弦变换)域的视频水印嵌入方案。该方案选取包含较多版权信息的灰度图像作为水印信息,根据纹理特征选择水印嵌入域,并将水印嵌入到部分解码视频I-VOP色度块的DC中。实验数据表明,在保证视频效果不失真的前提下,该方案具有良好的鲁棒性。     

基于QDCT全局均分策略的鲁棒视频水印方案

视频水印作为一种应用前景广阔的版权保护技术,近年来受到了广泛关注。与原始域方案不同,压缩域方案不需要完全编解码视频,具有更高的效率;并且视频存储和传输一般需要经过压缩编码才能进行,使得压缩域的鲁棒视频水印方案成为了研究热点。但现有的压缩域方案大多利用压缩域中的QDCT系数个体来嵌入水印,使得算法的鲁棒性不高。为了增加压缩域算法的鲁棒性,文中提出了一种基于QDCT全局均分策略的鲁棒视频水印方案。首先,利用非零系数个数选出视频中兼具纹理和高空间复杂度的块作为水印块,将两块水印块组成块对;然后,分别计算出块对中所有系数的总和,根据系数总和的大小以及水印信息,通过全局均分策略修改后序块内所有非零系数的幅值,来满足方案设置的块对系数和规则,以实现水印的嵌入。实验结果表明,在保证含水印视频具有较高视觉质量的前提下,该方案抵抗重压缩攻击和噪声攻击的鲁棒性均优于现有压缩域的鲁棒视频水印方案,分别提高了8%,9%。     

基于ICA运动目标检测的自嵌入视频认证水印

为了对视频中关键内容是否经受篡改实施有效验证和保护,提出了一种基于运动目标检测的自嵌入视频认证水印方案。由于运动目标集中了视频的关键信息,采用独立分量分析技术从连续的视频帧中分离出运动分量信息生成水印,并用奇异值分解方法对水印作预处理,采用DCT方法自嵌入到视频帧中去。实验结果表明,该水印方案在保证视频质量的前提下,对于常见攻击处理和局部篡改具有很好的鲁棒性,可以有效地验证视频关键信息是否遭到篡改,并且能够恢复出被篡改的关键内容,有效地保护视频完整性。     

一种新的适用于广播监视的安全视频水印算法

在广播临视应用中,需要对视频片段进行认证.使用三维离散小波变换和中值量化方法,提出一种新的利用密钥生成鲁棒视频散列的算法.提出的散列算法对于视频编辑以及有损压缩都具有很好的鲁棒性.并在此基础上提出一种适用于广播临视的安全视频水印方案.该方案利用生成的散列值和版权标识形成待嵌入的水印信息,以实现对视频片段的认证.理论分析和实验结果表明,提出的算法具有较高的安全性和鲁棒性.     

图像水印算法研究新进展

随着信息网络化飞速发展,数字水印作为网络环境下数字图像版权保护和完整性验证的重要技术,得到了广泛研究和应用。本文综述了图像水印技术的最新进展情况,阐述了图像水印的关键技术,分析了鲁棒性水印算法、半脆弱性水印算法和脆弱性水印算法的主流方案、特点和最新进展。最后,展望了图像水印技术的发展趋势。     

一种抵抗共谋攻击的数字视频水印算法

针对视频水印在共谋攻击中的鲁棒性，在离散余弦变换域，对视频内容特征进行了研究，提出了水印信息和水印位置信息同时关联于嵌入点内容的算法，并给出了水印算法鲁棒性检测实验，实验证明该算法对共谋攻击有良好的鲁棒性。     

多级多维DCT域的视频水印方案

利用DCT能量集中的特性,提出了基于多级多维DCT的视频水印算法.在视频帧内、帧间进行分级,在每一级采取不同维数的DCT变换,生成DCT系数立方体,选择适当的DCT系数实现水印信息的嵌入.实验证明,该方案较之直接3D-DCT域水印方案具有较高的视觉掩蔽性以及较强的鲁棒性.     

MPEG-4视频数字水印技术的设计与实现

介绍了数字水印技术的基本原理,以MPEG-4为例,提出并实现了一种改进的基于扩展频谱的视频水印方案。实践证明,该视频水印方案在不降低视频质量的基础上,能够抵抗多种干扰和攻击,具有良好的稳定性和鲁棒性。     

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.     

基于图像特征的鲁棒性数字水印算法

为了同时实现图像版权保护和图像内容的真伪性鉴定,提出了一种基于数字图像特征的鲁棒性数字水印算法。先利用Hessian变换提取宿主图像的特征区域,并根据每个特征区域内各个像素点的局部方向,将用于版权保护的水印信息嵌入到这些特征区域中。同时,向图像中除特征区域之外的区域嵌入用于图像内容真伪鉴定的脆弱性水印。水印提取过程是水印嵌入的逆过程,在不需要原始图像的情况下实现了版权水印和内容鉴定水印的提取。实验表明,该算法能抵杭大多数的移除攻击等几何篡改,对篡改发生的位置定位效果良好。     

人眼视觉特性与SIFT相结合的视频双水印算法

针对视频水印容易遭受几何攻击以及水印的鲁棒性与透明性的平衡问题,提出一种基于人眼视觉特性与尺度不变特征变换（SIFT）相结合的抗几何攻击视频双水印算法。首先获取视频序列中人眼视觉掩蔽阈值作为水印的最大嵌入强度。其次,将视频帧进行离散小波变换（DWT）,对中高频子带系数提出基于视频运动信息的自适应水印算法;针对低频子带,提出基于小波低频系数统计特性的抗几何攻击视频水印算法。最后,以SIFT作为触发器判断视频帧是否遭受几何攻击,对遭受几何攻击的视频帧利用SIFT的尺度与方向不变性进行校正,并对校正后的视频帧提取水印信号;针对非几何攻击的视频帧,直接利用中高频提取算法。所提算法与实时性视频水印算法——基于小波域直方图的视频水印（VW-HDWT）算法比较,峰值性噪比值（PSNR）提高了7.5%;与基于特征区域的水印算法相比,水印嵌入容量提高约10倍。实验结果表明,在保证水印透明度较好的情况下,所提算法对常规几何攻击具有较强的鲁棒性。     

基于Watson视觉模型的自适应视频水印

提出了一种基于Watson视觉模型的自适应视频水印，Watson视觉模型用于控制水印的嵌入强度。借助于该视觉模型，很容易权衡水印鲁棒性和感知透明性的关系。经过实验证实，该水印系统对常用的视频攻击（MPEG压缩、帧丢失、帧剪切、帧重排）是鲁棒的，同时具有感知透明性和实时性等特性。     

A robust watermarking scheme for 3D triangular mesh models

Copyright protection of digital media has become an important issue in the creation and distribution of digital content. As a solution to this problem, digital watermarking techniques have been developed for embedding specific information identifying the owner in the host data imperceptibly. Most watermarking methods developed to date mainly focused on digital media such as images, video, audio, and text. Relatively few watermarking methods have been presented for 3D graphical models. In this paper we propose a robust 3D graphical model watermarking scheme for triangle meshes. Our approach embeds watermark information by perturbing the distance between the vertices of the model to the center of the model. More importantly, to make our watermarking scheme robust against various forms of attack while preserving the visual quality of the models our approach distributes information corresponds to a bit of the watermark over the entire model, and the strength of the embedded watermark signal is adaptive with respect to the local geometry of the model. We also introduce a weighting scheme in the watermark extraction process that makes watermark detection more robust against attacks. Experiments show that this watermarking scheme is able to withstand common attacks on 3D models such as mesh simplification, addition of noise, model cropping as well as a combination of these attacks.     

一种抗几何攻击的视频水印算法

提出了一种基于视频序列时空不变信息的视频水印算法。在嵌入水印时生成同步帧，并确定同步帧时空不变特征点位置，检测时根据同步帧时空不变特征点的位置，实现对视频序列几何失真的矫正，对水印信息进行检测和提取。实验表明，该算法能有效地抵抗帧插入和帧丢失等时间轴同步攻击和高强度几何攻击。     

一种带纠错编码的小波域盲水印算法

先前众多的DWT(discretewavelettransform)域水印算法几乎都是私有水印或易脆水印,而针对版权保护的鲁棒的、公开的小波域水印算法却极少。文章提出了一种小波域盲水印算法,水印嵌入到小波分解的高频子带,通过采用小波系数的数字化编码技术实现了盲水印的提取。水印在提取过程中不需要任何原始图像信息。为提高水印的鲁棒性,引入了简单的纠错编码机制。     

A robust video watermarking algorithm based on singular value decomposition and slope-based embedding technique

In this work, we propose a robust watermarking algorithm for video copyright protection. The proposed algorithm is characterized by four key features. First, a robust feature obtained by singular value decomposition is selected to embed the watermark. Second, a novel slope-based embedding technique is developed to embed a 1-bit watermark into several successive blocks in the temporal direction, thus enhancing the robustness against global attacks. Third, an embedding location selection method is used to give priority to blocks with small variations that can enhance the visual quality of the watermarked video. Fourth, a temporal synchronization method is introduced to effectively withstand temporal synchronization attacks. The experimental results demonstrate that our scheme has good imperceptibility and is robust against various attacks, such as noise addition, filtering, gamma correction, lossy compression, scaling, frame dropping, frame insertion, and frame averaging. Furthermore, the watermark can be extracted using only some side information rather than the original video, which makes the scheme more practical.     

A low cost fragile watermarking scheme in H.264/AVC compressed domain

H.264/AVC-based products have grown tremendously in social networks; issues of content-based authentication become increasingly important. This paper presents a blind fragile watermarking scheme for content-based H.264/AVC authentication, which enjoys high sensitivity to typical video attacks. A spatiotemporal analysis is exploited to guarantee a minimum impact on perceptual quality and bit-rate increment. The watermark features are extracted from intra/inter prediction modes of intra/inter macroblocks, constituting the content-based Message Authentication Code (MAC) which is embedded/extracted in a Group-of-Pictures GOP-based fashion utilizing the syntactic elements of the Network Application Layer (NAL) units from the compressed bitstream. It’s unnecessary to fully decode a compressed bitstream before the embedding or detection processes. A content-based key is generated to control fragile watermark generation, embedding, extraction, and verification algorithms. Additionally, fragility is ensured by selecting the last nonzero quantized ac residuals for watermark embedding. The embedded watermark can be detected and verified by means of partially decoding intra/inter prediction modes from syntactic elements of the bitstream without the prior knowledge of the original video or complete decoding. Experiment results demonstrate that the performance of the proposed scheme is excellent in terms of bit-rate and perceptual quality. Furthermore, various types of content-preserving and/or content-changing attacks can be detected efficiently.     

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。