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1.
基于DWT域的灰度图像数字水印算法   总被引:1,自引:0,他引:1  
温蕴 《微计算机信息》2008,24(12):246-247
本文提出一种基于DWT域的灰度图像数字水印算法.该算法在对原始图像进行离散小波变换之前,首先将它进行Arnold置乱变换,然后再进行小渡分解,把分解后得到的高频子带系数(LH3)组成一个矩阵,对该矩阵进行奇异值分解(SVD),在奇异值分解的对角阵中嵌入水印.该算法采用有意义的灰度图像作为水印,极大地增加了嵌入水印的信息量.实验结果表明,水印对一般的图像攻击方法具有较强的鲁棒性.  相似文献   

2.
提出一种基于离散小波变换(DWT)的数字水印进行图像版权保护的新方法.将一幅有意义的二值图像作为水印来隐藏,先将水印图像使用推广Arnold的变换进行置乱后和图像同时进行多尺度分解,然后将分解后的水印系数根据人类视觉系统(HVS)特性自适应地嵌入到具有相同尺寸的低中频系数中,重构得到水印图像.实验结果表明,该算法具有较好的不可见性、鲁棒性和安全性.  相似文献   

3.
基于混沌序列的数字水印图像认证算法   总被引:1,自引:0,他引:1       下载免费PDF全文
本文在研究离散小波分解和混沌序列特点的基础上,提出了一种新的基于DWT域半脆弱水印算法。该算法以小波系数之间的关系作为水印信息,利用混沌映射产生一个密钥来加密水印信息,并分别嵌入到图像块深层小波域的低频子图中。水印的检测不需要原始图像。大量仿真结果证明,该算法嵌入的数字水印既具有很好的隐蔽性,又具有很理想的鲁棒性。  相似文献   

4.
孙燕飞  王凤英 《计算机仿真》2007,24(12):336-339
针对数字图像DWT系数的分布特点,分别对在不同频段系数中嵌入和提取水印进行了研究与实验.选用了有意义的灰度图像作为水印,采用基于混沌序列的加密方法对水印进行处理,在水印嵌入域上,选择了具有与人眼视觉特性十分相符的离散小波变换,通过将原始图像进行多级小波分解,在中间某一级或几级的小波系数中嵌入水印信息,从而加大了水印嵌入的灵活性.实验结果表明,在DWT低频域嵌入水印,对算法的透明性影响较大;在中高频域嵌入水印,对透明性的影响相对小一些,并且可加入的水印容量相对较大,但对低通类图像处理鲁棒性较弱.因此可以将各种方案相互融合、相互补充以均衡抵抗各种不同类别的攻击,并根据实际需求进行方案的选择.  相似文献   

5.
一种基于DWT的多重混合数字图像水印方案   总被引:1,自引:2,他引:1  
针对数字图像DWT系数的分布特点,该文分别对在DWT的不同频段系数中嵌入和检测水印进行了研究与试验,并在此基础上实现了一种基于DWT的多重混合数字图像水印方案。在小波域低频部分使用扩频的方法将m_序列作为水印加入图像,同时在小波域中、高频部分将满足标准正态分布N(0,1)的实数伪随机序列作为水印加入图像,而且每种水印都实现了盲检测。实验结果表明,这种多重混合水印方案兼顾了各频段水印嵌入检测的不同特性,在满足透明性要求的前提下,比单重水印方案在鲁棒性方面有了较大的提高。  相似文献   

6.
小波包特征熵分解的图像水印算法   总被引:1,自引:0,他引:1       下载免费PDF全文
提出了一种小波包特征熵分解的自适应图像水印算法。该算法通过对宿主图像进行小波包特征熵分解,在高频系数中选取合适的阈值来区分高频系数中图像的纹理细节信息和噪声信息,将水印信息自适应地嵌入到高频系数当中。实验表明,该水印算法对噪声、JPEG2000压缩、滤波、改变对比度、几何剪切等攻击都具有一定的健壮性。  相似文献   

7.
针对网格环境中图像信息资源的版权保护问题,提出了一种可应用于网格环境下的基于离散小波变换DWT和扩频技术的有意义数字水印算法.该算法在传统的基于DWT和扩频技术的有意义数字水印算法中,利用小波变换的多分辨率特性来进行图像的小波分解和重构,利用数字扩频技术来实现嵌入和检测水印.实验证明选择频域嵌入水印可以获得更好的图像保真度,并且比在空域中的水印算法更稳健,可实现在网格环境下的版权保护.  相似文献   

8.
提出了一种基于DWT域的图像数字水印算法。通过对宿主图像、经过Arnold变换加密后的水印图像分别进行多分辨率小波分解,达到自适应嵌入水印信息的目的。实验结果表明,该方法嵌入的数字水印不但具有较好的不可见性,而且对图像处理有较好的鲁棒性。  相似文献   

9.
提出了一种基于DWT域的图像数字水印算法。通过对宿主图像、经过Amold变换加密后的水印图像分别进行多分辨率小波分解,达到自适应嵌入水印信息的目的。实验结果表明,该方法嵌入的数字水印不但具有较好的不可见性,而且对图像处理有较好的鲁棒性。  相似文献   

10.
一种基于HVS的图像小波域鲁棒性数字水印   总被引:4,自引:0,他引:4       下载免费PDF全文
提出了一种基于人类视觉系统(HVS)和离散小波变换(DWT)的图像鲁棒数字水印新算法。将宿主图像进行小波分解,根据人类视觉系统的掩蔽特性计算出JND视觉门限值,选择重要小波系数,将数字水印分别嵌入到重要小波系数的不同频率域中。水印嵌入采用改进的二值运算方法,修改小波系数的小数部分,以提高水印嵌入后图像的质量。实验证明算法在保证水印不可见性的前提下有效地提高了算法的鲁棒性,对JPEG压缩、图像添加噪声、缩放、剪切和中值滤波等攻击有很强的鲁棒性。  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.
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   

19.
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   

20.
This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)SM and Team Software Process (TSP){SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.  相似文献   

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