基于网格平面化的三维数字水印算法研究

提出了将成熟的二维数字水印技术运用到三维模型水印的思想。鉴于寻找三维模型几何与拓扑不变量的难度，提出了将三维数据转换到二维空间，直接运用二维水印算法。利用平面参数化建模方法，把原始几何信号转换成具有相同频谱特性的平面信号，实现了基于网格平面化的三维数字水印算法。     

基于音频内容的DCT域脆弱水印算法

为了实现音频文件的完整性认证,提出了一种基于内容的脆弱水印算法.对于一维序列,改变其离散余弦变换(DCT)域交流系数不会改变该序列的幅值和.基于这一性质,在音频分帧后,再对每帧分组,计算每组采样点和的绝对值,相加后得到该帧的和,将其作为该帧音频的特征,量化后转换为二进制作为水印;然后,用量化索引调制方法,通过调整每组DCT域的低频系数嵌入水印.实验表明:该算法具有很好的不可感知性;得到的含水印音频的信噪比约为80 dB;算法对添加噪声、重量化、重采样、低通滤波、MP3压缩等操作具有很强的敏感性,并且能够确定替换等恶意篡改的位置.     

Research on anti-counterfeiting quick response 2D barcode techniques based on digital watermark

In order to increase the watermarking capacity and improve the anti-counterfeiting performance of quick response (QR) two-dimensional (2D) barcode based on digital watermarking technique, this paper proposes a kind of graying algorithm for binary image to make transform domain watermarking methods possible. Based on the graying algorithm, the quantization-based watermarking scheme in discrete wavelet transform (DWT) domain is then designed. The experiments show that the proposed watermarking scheme for QR 2D barcode greatly improves anti-counterfeiting performance without loss of any barcode information.     

一种基于Arnold混沌映射的数字水印技术研究

数字水印技术作为版权保护的重要手段,已得到广泛地研究和应用．提出了一种基于Arnold混沌映射的数字水印技术和水印信息置乱效果评价方法,用Arnold变换对原始水印信号进行置乱,再经过M序列扩频,将处理后水印信号嵌入宿主图片小波域的低频系数中,通过对四组不同条件和嵌入方法的比较,通过实验证明该算法具有良好的稳健性．     

基于水印序号的抗裁剪音频数字水印算法

提出一种基于水印序号的抗裁剪音频数字水印算法.该算法在音频信号中嵌入同步码、水印序号和二值水印图像,具有如下特点:利用同步技术,能有效对抗音频信号受到的随机裁剪攻击;水印序号的嵌入,能使检测到的水印信息自动定位在图像上.仿真实验表明,该算法在抵抗加性噪声和裁剪攻击等方面达到了较高的鲁棒性.     

基于小波域数字水印技术的图像版权保护方法

提出了一种基于人眼视觉特性的小波变换数字水印算法,该算法能够依据人眼视觉特性,将水印信息嵌入到小波变换域的不同尺度、不同方向分量上,从而提供检测局部空域和频域变化的能力,实现局部水印和全局水印之双重目的.实验结果表明：所提出的数字水印不仅具有较好的透明性,而且对诸如剪切、低通滤波等攻击均具有较好的鲁棒性.     

Robust digital audio watermarking scheme using blind source separation with global optimal property

The paper proposes a robust digital audio watermarking scheme using blind source separation(BSS) based on the global optimization of independency metric(IM),which is formulated as a generalized eigenvalue(GE) problem.Compared with traditional information-theoretical approaches used in digital audio watermarking,such as fast independent component analysis(FastICA),the proposed scheme has lower complexity without timeconsuming iteration steps used in FastICA.To make full use of the multiresolution characteris...     

A semi-fragile wavelet transform watermarking scheme for content authentication of images

A novel semi-fragile watermarking scheme for the content authentication of images using wavelet transform (WT) is presented in this paper. It is tolerant to the embedded wavelet image compression methods based on WT such as embedded zerotree wavelet (EZW), set partitioning in hierarchical trees (SPIHT) and embedded block coding with optimized truncation (EBCOT) in JPEG2000 to a pre-determined bit-plane, but is sensitive to all other malicious attacks. The image features are generated from the lowest-frequency (LF) subband of the original image as the embedded watermark. The watermark is embedded into the pre-determined bit-plane by adjusting the corresponding values in the given subband. In the process of watermarking authentication, we compare the image features generated from the LF subband of the received image with the embedded watermarking information (the image features of the original image) extracted from the pre-determined bit-plane in the given subband of the received image to decide whether the image is attacked maliciously or processed acceptably (the embedded wavelet compression). The most important advantage of our watermarking scheme is that the watermark information can be extracted from the watermarked image when detecting watermark, so the received image authentication needs no information about the original image or watermark. Experimental results prove the effectiveness of our proposed watermarking scheme.     

Novel Chaotic Fragile Watermarking Algorithm for Image Authentication

Taking full advantage of the randomicity of chaotic system and its extreme sensitivity to the initial value, a new chaotic fragile watermarking algorithm is proposed. In the algorithm, the location key is looked as a logistic chaotic initial value for iteration to create a location matrix. According to this location matrix, a mapping image is generated and the embedding location of watermarking in image blocks is identified. Then, the watermarking sequence, which is related with the mapping image blocks and generated by H6non chaotic map, is embedded into the least significant bit (LSB) of the corresponding location in each block. Since the image content and watermarking are staggered, the algorithm has a higher security. Simulation results showed that the algorithm can detect and locate the tamper in watermarked images with an accuracy of 2 x 2 block pixels. At the same time, the watermarking images has good invisibility, and the original image is not required when extracting watermarking.     

Web Page Watermarking for Tamper-Proof

IntroductionTraditional solutions for the integrity protec-tion of web pages are based on the File Digest tech-niques, usually called Digital Signatures[1]. Suchmethods generate a signature through Hash func-tions with the to-be-protected information as theinput and then attach it to the end of the originalinformation to form the signed message. When thesigned message arrives at the receiver, the correctsignature can ensure its integrity; in other words,no signature or a false one means that…     

抵抗线性共谋攻击的空域自适应视频水印方案

针对视频水印中存在的线性共谋攻击问题,建立了线性共谋攻击的数学模型,并根据建立的数学模型提出了抵抗线性共谋攻击的视频水印设计规则.基于该规则,提出了一种有效抵抗线性共谋攻击的视频水印方案.该方案从视频帧中自适应地选取一些互不重叠的8×8的块(子帧)作为嵌入区域,嵌入强度自适应于相应子帧的方差.实验表明,该算法在经过线性共谋、帧去除、帧插入、帧重组以及MPEG-2压缩等各种攻击后,水印提取的正确率仍可达到100%.     

基于离散小波变换和人类视觉系统的数字水印算法

通过对人类视觉系统（HVS）的亮度特性、频域特性、图像类型特性的研究,提出一种基于离散小波变换和人类视觉系统数字水印算法,将秘密信息嵌入到小波变换不同的方位系数中．实现了水印信号在图像信息中的嵌入与提取,达到隐藏秘密信息的目的．实践证明该算法能提高水印的不可见性,同时具有很强的鲁棒性．     

彩色图像中基于几何不变性的数字水印

常规的数字水印算法对几何攻击无能为力,水印算法对几何攻击的鲁棒性被认为是数字水印技术走上实际应用的一个关键点.文中通过对普通的基于几何不变性数字水印算法的分析,提出了一种彩色图像中基于几何不变性的数字水印的嵌入及检测过程,并通过一系列实验证明了该数字水印算法具有很高的抗几何攻击(旋转、缩放等)特性,即提高了鲁棒性.     

基于离散小波变换和人类视觉系统的数字水印算法

通过对人类视觉系统(HVS)的亮度特性、频域特性、图像类型特性的研究,提出一种基于离散小波变换和人类视觉系统数字水印算法,将秘密信息嵌入到小波变换不同的方位系数中.实现了水印信号在图像信息中的嵌入与提取,达到隐藏秘密信息的目的.实践证明该算法能提高水印的不可见性,同时具有很强的鲁棒性.     

Analysis and enhancement of a watermarking protocol suitable for web context

AbstractA buyer-seller watermarking protocol is a combination of traditional watermarking and fingerprinting techniques. Recently, Frattolillo proposed such a watermarking protocol suitable for web context. Frattolillo’s scheme has two problems which would make it hard to implement practically. Several possible solutions to the two problems are presented in this paper.     

A new buyer-seller watermarking protocol without double embedding

AbstractCopy deterrence is a digital watermarking application which enables a seller to identify the buyers who obtain digital content legally but illegally redistribute it. However, in many buyer-seller watermarking protocols proposed for copy deterrence, the seller has to embed two watermarks into each copy of the digital content before it is sold. In this paper, we propose a new buyer-seller watermarking protocol in which the seller can reduce the number of the embedded watermarks from two to one. The proposed protocol also provides a more efficient solution to the unbinding problem than that of Lei et al’s scheme.     

A Scheme of Fragile Watermarking Based on SVD and 2D Chaotic Mapping

Introduction TheInternetandtheadvancementofdigital technologieshaveenablednumerousapplicationsin theareasofmultimediacommunicationsandmulti-medianetworking.Atypicalcharacteristicofdigi-talproductsisthattheyareeasytomanipulate,i.e.tostore,duplicate,transmitormodify.Thus,theauthenticationandthecopyrightprotec-tionfromunauthorizedmanipulationofdigitalau-dio,image,andvideodatabecomeanessential concerninthedigitalmultimediaera[1].Digitalwa-termarkinghasattractedconsiderableattentionand seennumerou…     

基于小波变换的图像水印研究

研究了一种新的基于小波变换的数字水印技术。该项技术中,把强健水印嵌入至一幅图像中频率最低的部分,用于检测图像是否发生改变的脆弱水印则在较为粗糙的尺度下,通过对小波系数设置阈值及量化的方法嵌入到图像中。实验表明,强健水印具有抵抗非恶意图像变换（如有损压缩等）,而脆弱水印能检测到恶意的图像攻击（如修改或伪造图像中的某一部分）。     

Wavelet Transform Modulus Maxima-Based Robust Digital Image Watermarking in Wavelet Domain

A new robust watermarking approach was proposed in 2D continuous wavelet domain (CWT).The watermark is embedded into the large coefficients in the middle band of wavelet transform modulus maxima (WTMM) of the host image.After possible attacks,the watermark is then detected and extracted by correlation analysis.Compared with other wavelet domain watermarking approaches,the WTMM approach can endow the image with both rotation and shift invariant properties.On the other hand,scale invariance is achieved with the geometric normalization during watermark detection.Case studies involve various attacks such as shifting,lossy compression,scaling,rotation and median filtering on the watermarked image,and the result shows that the approach is robust to these attacks.     

Watermarking data cubes

We propose a robust watermarking scheme and several extensions for digital right management of data cubes. The ownership information is hidden into a data cube by modifying a set of selected cell values. Its owner can use his private key to control all the watermarking parameters freely. Neither original data cube nor the watermark is required in watermark detection. Detailed analysis and extensive experiments are conducted for the proposed schemes in terms of watermark detectability, robustness and efficiency. Our results show that the scheme performs well in actual applications.