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1.
提出一种利用小波进行综合纹理和形状特征的具有旋转、平移和尺度不变性的图像检索算法.使用角向矩加权方向定义图像的主方向来进行坐标轴的旋转矫正,得到图像的旋转不变性表示;采用具有平移和尺度不变性的小波变换对图像进行小波分解,利用各子带的能量作为纹理特征;利用小波分解的逼近子图重构图像并进一步利用Hu不变矩提取其形状特征.最后对纹理和形状特征进行高斯归一化,综合其特征进行检索.实验中对算法的尺度不变性、旋转不变性、平移不变性及对噪声的不敏感性进行了验证,实验结果证明了该算法具有更高的鲁棒性和查准率.  相似文献   

2.
为获得高品质的虹膜纹理特征,针对小波变换方向选择性差的局限和虹膜图像纹理丰富的特点,本文提出了一种基于轮廓波(Contourlet)变换的虹膜特征提取方法.首先对预处理后的虹膜图像进行Contourlet分解,然后根据高低频子带所表征的信息,采用不同特征提取策略,提取其低频分量的均值及标准差和不同尺度、不同方向上高频子...  相似文献   

3.
基于旋转不变纹理特征的多尺度多方向图像渐进检索   总被引:1,自引:0,他引:1  
纹理检索是基于内容图像检索的重要内容,旋转不变纹理图像检索是实现纹理检索的关键途径之一.针对旋转不变纹理图像检索中需要解决的3个关键问题:如何消除旋转影响、如何选择多尺度分析方法以及如何构造和度量纹理特征矢量,本文分别分析了Radon变换和Log-polar变换在消除旋转位移时对频谱的影响,以及NSCT变换和小波变换在不同检索参数下的平均检索性能,在此基础上构造出多尺度多方向纹理变换谱和旋转不变特征矢量,提出一种多尺度多方向旋转不变纹理图像渐进检索方法.这种方法采用了可顾及人类视觉对纹理能量敏感性的相似性度量标准,分别采用旋转位移处理后的NSCT变换域低频子带和高通子带实现纹理图像的粗检索和精细检索.Brodatz标准纹理图像库的检索实验表明,本文提出的利用多尺度多方向纹理变换谱构造旋转不变特征矢量的方法既可获取纹理主方向,同时又能有效地表征纹理细节信息,两级渐进式检索策略与多尺度分析方法相结合,既能提高旋转不变纹理图像检索的查准率,又能保证较高的检索效率.  相似文献   

4.
针对变换域中图像纹理识别时如何选择最佳特征向量的问题,利用Contourlet变换的多方向、多尺度选择性和各向异性,将图像从空间域变换到频率域,全面地提取了Contourlet变换分解后低频子带、中频子带和高频子带的特征,输入支持向量机(SVM)分类器进行分类识别。利用Brodatz纹理库进行仿真实验,实验结果表明低频均值方差和高频能量作为组合特征时识别准确率可达98.75%,且特征向量维数少,是在Contourlet变换下表示图像纹理的最优特征。  相似文献   

5.
提取纹理特征一直是纹理分析的首要问题。提出一种双树复小波域共生矩阵的纹理特征提取方法。利用双树复小波对纹理图像进行多层分解所得的低频子带图像,计算不同方向的共生矩阵,提取图像纹理特征值。实验结果表明,该方法能有效提取出多尺度、多方向的纹理特征,并兼顾纹理局部随机性和整体规律性,所提取的纹理特征具有良好的聚类分离度和类内样本差异性。  相似文献   

6.
基于离散平稳小波和非下采样方向滤波器组的纹理分类   总被引:1,自引:0,他引:1  
结合小波变换的多尺度性和Contourlet变换的多方向性,提出了一种新的基于离散平稳小波变换和无下采样方向滤波器组(stationary wavelet transform and nonsubsampled directional filter banks,SWT-NSDFB)的纹理分类方法,采用具有平移不变性的离散平稳小波先进行多尺度分解;然后对每层分解得到的高频子带采用非下采样方向滤波器组进行多方向分解,再计算低频子带和各层方向子带的能量作为纹理特征;最后用支持向量机实现纹理分类。实验结果表明,该  相似文献   

7.
基于剪切波变换的纹理图像分类   总被引:3,自引:0,他引:3       下载免费PDF全文
二维可分离小波在纹理分析领域得到了成功的应用,但它只提取图像水平、垂直和对角方向的频率信息,其变换滤波器是各向同性的,不能很好地表达纹理的细节。利用剪切波变换优良的多尺度性、局域性和方向性,提出一种基于剪切波变换(Shearlet transform)的纹理分类算法。该方法先对纹理图像做剪切波变换,得到各尺度、方向子带的剪切系数,计算尺度间子带能量比,以尺度间能量比为权对各子带能量加权,以加权后的子带能量作为特征矢量,用K邻近分类器进行分类。实验结果表明该方法比基于小波的纹理分类方法更加有效。  相似文献   

8.
为实现灰度共生矩阵(GLCM)多尺度、多方向的纹理特征提取, 提出了一种结合非下采样轮廓变换(NSCT)和GLCM的纹理特征提取方法。先用NSCT对合成孔径雷达(SAR)图像进行多尺度、多方向分解; 再对得到的子带图像使用GLCM提取灰度共生量; 然后对提取的灰度共生量进行相关性分析, 去除冗余特征量, 并将其与灰度特征构成多特征矢量; 最后, 充分利用支持向量机(SVM)在小样本数据库和泛化能力方面的优势, 由SVM完成多特征矢量的划分, 实现SAR图像分割。实验结果表明, 基于NSCT域的GLCM纹理提取方法和多特征融合用于SAR图像分割, 可以提高分割准确率, 获得较好的边缘保持效果。  相似文献   

9.
刘伟  张宏  周洁  童勤业 《传感技术学报》2007,20(5):1077-1081
使用希尔伯特-黄变换对医学图像进行分解并将分解产生的内蕴模态函数及其二维希尔伯特变换的幅值作为纹理特征,提取后的特征用于医学图像检索.根据图像内局部极值点的几何分布,提出了一种新的基于聚类算法的边界处理方法.实验中使用的纹理特征包括基于希尔伯特-黄变换得到的特征和对比用的Gabor特征、纹理谱特征和多尺度复杂性及多尺度分维数特征.初步的实验结果表明:采用希尔伯特-黄变换可以有效地描述医学图像的纹理信息,并取得较好的图像检索结果.  相似文献   

10.
为提高图割算法的分割效率与质量并改善shrinking bias现象,提出将图割理论与小波变换相结合的方法.该方法利用小波变换多分辨率分析的特点,将变换中的低频子带图像作为估计GMM参数的训练样本进行多尺度迭代分割,提高算法效率,利用简单高效的CS_LBP纹理描述子提取高频子带图像中的纹理信息,将颜色与纹理特征相结合改善分割效果,并利用高频系数进行多尺度边缘检测,用于计算局部自适应的正则化参数,改善对细长边界的分割.实验结果表明,分割效果得到了改善,算法效率得到了提高.  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.
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   

18.
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   

19.
蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。  相似文献   

20.
基于复小波噪声方差显著修正的SAR图像去噪   总被引:4,自引:1,他引:3  
提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。  相似文献   

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