摘要：为了解决目前彩信业务中移动数字内容的版权保护、使用控制及计费管理,提出了基于数字水印的版权保护与管理系统方案WDRM(watermark based digital rights management).设计了一种鲁棒的数字图像水印算法,以两个独立的水印,分别代表图片提供商信息和网络运营商信息;以待嵌入的信息为种子,产生具有良好自相关特性的随机序列作为水印信号,并根据人类视觉系统HVS(human vision system)的特性,对原始图像块进行分类,根据分类的结果将水印信号以不同的强度嵌入到图像块的DCT中频系数上;通过计算相关值来提取水印.实验结果表明,该水印算法能抵抗典型的图像处理,如加噪、滤波、压缩、增删线条或字等,基本满足当前彩信业务的要求.
摘要：This paper presents a detailed experimental analysis of a DCT-domain watermarking scheme based on convolutional coding techniques. Our results show that choosing suitable convolutional code can considerably alleviate the trade-off between the capacity and the robustness against most of attacks.%提出了一种结合卷积码技术的DCT域数字图像水印体制,并给出详细的分析结果.实验表明,选择合适的卷积码运用于水印体制能缓解水印体制的隐藏容量与鲁棒性之间的矛盾,并能抵抗大多数恶意攻击.
摘要：To propose one publicly detectable watermarking plan using error correcting code. The algorithms for the watermark embedding and extracting are both open, and public key cryptosystem is utilized instead of common watermark key. Anyone can extract and verify the digital watermark embedded in the image, but no one can destroy or alternate the watermark, or retrieve the original image without the corresponding private key. Error correcting code is used to eliminate the negative effect of noise in watermark embedding/extracting and image encryption.%提出了一种采用纠错码的可以公开检测的水印方案.水印的嵌入和提取算法都是公开的,公钥系统取代了普通的水印密钥.任何人都可以提取并检测嵌入在图像中的数字水印,但是却不能破坏或更改水印,如果没有相应的私钥也无法获得原始图像.纠错码用于消除水印嵌入/提取和图像加密过程中噪声的负面影响.
摘要：提出了一种新的基于SVD(singular value decomposition,奇异值分解)和ICA(independent component analysis,独立分量分析)的鲁棒水印算法.采用二值图像作为水印,并进行Arnold变换,提高了安全性.SVD用于水印的嵌入过程,ICA用于水印信号的提取.该算法的水印容量大大提高,同时还保证了鲁棒水印的不可感知性.借助于ICA,该算法在不需考虑水印图像所经历的攻击类型及攻击参数的情况下,能够正确提取水印信号.实验结果表明,该算法对于JPEG压缩、噪声等具有鲁棒性,尤其对于几何攻击如旋转、剪切、伸缩具有很好的鲁棒性.
摘要：Knowledge grid is very popular today.A unique method based on knowledge mining is set up to solve the problem on security of grid node. It is very useful to construct the grid security architecture. This architecture is used to provide grid-based security knowledge mining services and the embranchment boundary deciding principle is mentioned to describe the details.%知识网格如今研究的越来越普遍,基于知识挖掘提出了一种独特的解决网格节点安全性的方法.这对于建立网格安全体系结构非常有用.这种结构提供了一种网格安全的基础知识挖掘服务,并利用分支定界法则做了仔细的讨论.
