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1.
针对多通道水印模型限制鲁棒水印容量和降低水印图像隐形性问题,提出基于零参考水印的多通道数字图像水印方案。该方案基于量化函数定义各水印通道的零参考水印。检测时可以提取参考水印,比较零参考水印和提取的参考水印,计算各水印通道的失真率,根据失真率计算嵌入的鲁棒水印。实验结果表明,该方案在保持水印图像隐形性的前提下,提高了水印提取准确度。  相似文献   

2.
一种几何攻击下的数字图像水印检测方法   总被引:2,自引:0,他引:2  
几何攻击是数字图像水印众多攻击的一种,它不试图破坏图像中的水印信号,而是使水印检测器与水印信号失去同步,致使水印检测器检测不到水印信号,是一种有效的水印攻击方法。该文介绍了一种基于标准化的互相关NCC(normalized-cross correlation)图像固有特征提取及特征点匹配方法,进而利用图像固有特征恢复经几何变换的水印图像,使水印检测器与水印同步以达到有效检测水印的目的。实验表明,使用该方法能较好地恢复图像,有效地同步水印检测器与水印信号,从而使水印对仿射变换攻击具有鲁棒性。  相似文献   

3.
基于离散小波变换的盲水印研究与仿真   总被引:1,自引:1,他引:0  
研究优化水印安全性问题.由于水印图像应具备版权信息和密钥条件,针对目前音频水印算法中水印容易被提取,且检测水印时均需要原始水印图像,导致水印安全性,鲁棒性无法保证.提出了基于离散小波变换的混沌加密的音频数字水印盲算法.将混沌原理引入音频水印中,改善了水印的安全性,同时根据信号的能量对水印进行了量化嵌入,改善了水印的鲁棒性.首先利用密钥对二值水印图像进行随机置乱;然后将经过随机置乱处理的含有版权信息的二值水印图像嵌入到原始音频信号中.在水印检测过程中利用已知的密钥对水印进行重构.仿真证明,在不知道密钥的情况下,无法得出水印图像,为设计提供了依据.  相似文献   

4.
一种基于图象内容的小波域鲁棒水印技术   总被引:1,自引:0,他引:1       下载免费PDF全文
为了提高水印的鲁棒性及抗攻击能力,提出了一种基于图象内容的小波变换域水印技术,该技术是将水印内容的选取与原始图象的内容相联系,并在水印嵌入之前,先对水印进行伪随机排列,分块,扩展等预处理,以增强鲁棒性,其与传统的水印方法不同的是,在水印嵌入过程中选将分块后的水印嵌入,然后将整个水印嵌入,这样水印不仅嵌入到图象小波分解系数的低频分量中,也嵌入到高频分量中,而提取过程中,也同样提取分块后的水印和整个水印,并将基于图象内容的水印与事先给定水印在相同条件下进行了比较实验,实验结果表明,这种水印技术的鲁棒性明显好于传统水印技术,同时还证明了水印嵌入的容量不仅与视觉系统的刚刚可分辨门限有关,而且与水印信号本身的一些特性有关系。  相似文献   

5.
朱俚治 《微机发展》2014,(9):141-145
鲁棒性是水印的重要特性之一,水印鲁棒性强度恰当与否决定着水印的好坏。因此,水印鲁棒性衡量至关重要。文中提出了新的衡量水印算法,新算法将被攻击后的水印作为函数变量。首先对水印被攻击后给水印所造成的损坏进行分类,之后以原始水印作为衡量水印鲁棒性的基准,通过计算提取水印偏离原始水印程度的值,将所得到的值使用中介真值程度度量的方法对水印鲁棒性进行衡量。中介真值程度度量的方法在数字水印上的应用尚属首次。最后进行了算法分析。  相似文献   

6.
针对载体图像内容安全与数字水印版权保护,结合Arnold置换与直方图平移可逆水印算法,提出基于Arnold置换的交换加密水印算法.算法利用置换后图像直方图不变的特性,将在密文中嵌入水印的操作映射到明文中,实现了加密与水印操作先后顺序的交换.在提取水印时,可直接从含水印的密文中提取水印,也可解密后再提取水印.实验结果表明,该算法加密操作与水印嵌入操作间的先后顺序不影响含水印密文的生成,解密操作与水印提取操作的先后顺序不影响水印提取与图像恢复,且直接解密得到的含水印明文图像质量较高,水印的不可见性好,算法有较高的效率.  相似文献   

7.
李琦  王春鹏  王晓雨  李健  夏之秋  高锁  马宾 《软件学报》2023,34(9):4351-4361
传统的水印攻击方法虽然能够干扰水印信息的正确提取, 但同时会对含水印图像的视觉质量造成较大损失, 为此提出了一种基于残差学习的新型不可感知水印攻击方法. 首先, 通过构建基于卷积神经网络的水印攻击模型, 在含水印图像和无水印图像之间进行端到端非线性学习, 完成含水印图像映射到无水印图像的任务, 达到水印攻击的目的; 其次, 根据水印信息的嵌入区域选择合适数目的特征提取块以提取含水印信息的特征图. 鉴于含水印图像和无水印图像之间的差异过小, 水印攻击模型在训练过程中的可学习性受到限制, 导致模型很难收敛. 引入残差学习机制来提升水印攻击模型的收敛速度和学习能力, 通过减少残差图像(含水印图像和提取的特征图像做差)与无水印图像之间的差异来提升被攻击图像的不可感知性. 此外, 还根据DIV2K2017超分辨率数据集以及所攻击的基于四元数指数矩的鲁棒彩色图像水印算法构建了训练水印攻击模型的数据集. 实验结果表明该水印攻击模型能够在不破坏含水印图像视觉质量的前提下以高误码率实现对鲁棒水印算法的攻击.  相似文献   

8.
基于中国剩余定理的动态水印方案   总被引:2,自引:1,他引:2       下载免费PDF全文
白雪梅  凌捷 《计算机工程》2006,32(16):155-157
针对动态图水印性能指标之间的制约关系,提出了从分解水印图变为分解水印数据以提高隐藏信息量的设计思想,分析了称为抽象水印的方案,并结合动态图水印的明显优势,给出了一种基于中国剩余定理的动态水印方案。通过分析提高了动态水印性能的策略,指出软件水印技术的进一步发展方向。  相似文献   

9.
彭川  莫海芳 《计算机仿真》2012,29(9):278-282
数字图像水印研究中,针对图像水印鲁棒性和隐蔽性的矛盾、数字水印本身的安全问题,结合混沌系统原理,提出一种Logistic双混沌系统的鲁棒数字图像水印方案。不同于许多传统水印算法,水印嵌入时不将原始水印嵌入,而是根据密钥生成两个混沌序列作为水印序列,然后按照规则,依次根据原始水印的每个比特值选取某个混沌水印序列的一比特信息嵌入载体图像对应的DCT中频系数中。在提取水印时,根据DCT的中频系数和混沌水印序列的相关性来确定每一位原始水印比特值,最终合并得到完整的水印图像。由于水印序列的产生过程经过了混沌加密处理,所以算法效率较好,且保证了水印本身的安全性。仿真结果表明,水印嵌入和提取算法都具有良好的效果,并且具有较强的抗攻击性能。  相似文献   

10.
针对动态图水印数据率低、水印信息遭到攻击后不易恢复的问题,提出了一种水印信息可恢复的软件水印方案。该方案结合了动态图水印和线程水印技术。为了使水印信息可恢复,在水印的嵌入过程中,利用设计的一种特殊的动态图结构表示水印信息,并在程序的线程关系中隐藏动态图的纠错码信息。提取水印图的过程中一旦检测到水印图遭到窜改,提取隐藏在程序执行时产生的线程关系中的纠错码信息,恢复被窜改的水印信息。理论分析和实验表明,该方案提高了水印的数据率,降低了程序负载,增强了水印的抗攻击性,并能在一定程度上恢复被窜改的水印信息。  相似文献   

11.
Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.  相似文献   

12.
European Community policy and the market   总被引:1,自引:0,他引:1  
Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.  相似文献   

13.
融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。  相似文献   

14.
Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.  相似文献   

15.
This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.  相似文献   

16.
Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   

17.
《计算机科学》2007,34(4):148-148
Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.  相似文献   

18.
为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.  相似文献   

19.
Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.  相似文献   

20.
正The 34th Chinese Control Conference and SICE Annual Conference 2015(CCCSICE2015)is organized by the Technical Committee on Control Theory(TCCT)of Chinese Association of Automation(CAA)and the Society of Instrument and Control Engineers(SICE)of Japan,and locally organized by Hangzhou Dianzi University(HDU).  相似文献   

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