共查询到20条相似文献,搜索用时 31 毫秒
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基于角点的红外与可见光图像自动配准方法 总被引:3,自引:2,他引:1
针对红外图像与可见光图像的自动配准问题,提出了一种基于图像角点特征以及仿射变换模型的方法.利用Harris因子分别在红外图像和可见光图像上检测角点,并对两幅图像进行边缘检测,得到其边缘图像.通过角点邻域在边缘图像上的相关性,实现角点的粗匹配;通过角点的细匹配,从匹配的角点中选择两对匹配最佳的点作为仿射变换的控制点,得到仿射变换模型,并对待配准图像进行仿射变换,从而实现图像配准.实验结果表明:该方法运算速度快,可以很好地完成红外与可见光图像的自动配准. 相似文献
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Feature selection is one of the core contents of rough set theory and application. Since the reduction ability and classification performance of many feature selection algorithms based on rough set theory and its extensions are not ideal, this paper proposes a feature selection algorithm that combines the information theory view and algebraic view in the neighborhood decision system. First, the neighborhood relationship in the neighborhood rough set model is used to retain the classification information of continuous data, to study some uncertainty measures of neighborhood information entropy. Second, to fully reflect the decision ability and classification performance of the neighborhood system, the neighborhood credibility and neighborhood coverage are defined and introduced into the neighborhood joint entropy. Third, a feature selection algorithm based on neighborhood joint entropy is designed, which improves the disadvantage that most feature selection algorithms only consider information theory definition or algebraic definition. Finally, experiments and statistical analyses on nine data sets prove that the algorithm can effectively select the optimal feature subset, and the selection result can maintain or improve the classification performance of the data set. 相似文献
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An improved Harris corner detection algorithm is proposed based on Barron operator, since Harris corner detection algorithm has a poor accuracy in positioning complex corner detection and may miss certain real corners. Firstly, the image gradient is calculated by using Barron operator to reduce the calculation errors from Prewitt operator or Sobel operator. Secondly, the centre B-spline function is used to smooth image, filter noise, and retain the corners information better. Thirdly, a non-maximal inhibition and corners sieving method is used to determine whether the detected corners are real corners or not. A square window is centered at the pixel and eliminate the corner if the value of the corner response function is non-maximal in the window. And then divide the test image into several blocks so as to process each block independently, and use a cyclic iterative method to determine the threshold value to make sure that the real corners are accurately selected. Finally, experiments indicate the algorithm has relatively great noise proof ability and is able to extract complex corners effectively. 相似文献
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A. V. Brovenko P. N. Melezhik A. E. Poedinchuk 《Radiophysics and Quantum Electronics》1998,41(10):908-915
We propose a new method for studying the spectral characteristics of open cavities containing circular metal-dielectric cylinders.
As a result, an algorithm for calculating the natural-frequency spectrum of such a class of electrodynamic structures is developed.
A numerical comparative analysis of the spectral properties is carried out for a two-mirror, confocal, open cavity with a
circular metal-dielectric cylinder and a similar cavity with the corresponding radial-layered dielectric cylinder.
Acad. A. Ya Usikov Institute of Radiophysics and Electronics of the National Academy of Sciences, Kharkov, Ukraine. Translated
from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 41, No. 10, pp. 1336–1347, October 1998. 相似文献
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James Bremer 《Journal of computational physics》2012,231(4):1879-1899
We describe an approach to the numerical solution of the integral equations of scattering theory on planar curves with corners. It is rather comprehensive in that it applies to a wide variety of boundary value problems; here, we treat the Neumann and Dirichlet problems as well as the boundary value problem arising from acoustic scattering at the interface of two fluids. It achieves high accuracy, is applicable to large-scale problems and, perhaps most importantly, does not require asymptotic estimates for solutions. Instead, the singularities of solutions are resolved numerically. The approach is efficient, however, only in the low- and mid-frequency regimes. Once the scatterer becomes more than several hundred wavelengths in size, the performance of the algorithm of this paper deteriorates significantly. We illustrate our method with several numerical experiments, including the solution of a Neumann problem for the Helmholtz equation given on a domain with nearly 10000 corner points. 相似文献
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一种基于清晰度计算的NSCT域多聚焦图像融合算法 总被引:1,自引:0,他引:1
针对多聚焦图像的特点.提出了一种基于清晰度计算的非抽样轮廓波变换(Non-Subsampied Contourlet’Transform,NSCT)域多聚焦图像融合算法。该算法首先对源图像进行NSCT分解.以此克服传统Contourlet变换不具平移不变性的缺点。在分析光学成像中散焦表现形式的基础上.对分解后的低频子带和高频方向子带分别以“邻域梯度”及“合成邻域模值”作为清晰度指标。采用自适应选择法实现对多聚焦图像的融合处理。实验结果表明,该方法不仅能有效融合图像中的“伪影”和“振铃效应”.视觉效果明显优于传统小波和Contourlet方法,且融合图像的熵、交叉熵及均方根交叉熵等客观评价指标也有明显提高。 相似文献
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V. G. Arakcheev A. N. Bekin Yu. V. Vladimirova N. V. Minaev V. B. Morozov A. O. Rybaltovskii 《Moscow University Physics Bulletin》2014,69(4):330-335
We obtained a metal-dielectric composite by thermal restoration of silver atoms from an alcohol solution of a precursor in nanoporous glass with pores with a radius of 2 nm. The concentration, size, and asphericity degree of metal nanoparticles formed in the pores are characterized according to the measured extinction spectra of the material. 相似文献
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在近红外光谱数据相似性测度时,由于光谱数据高维、非线性、重叠等特点,会出现测度距离失效、数据信息处理困难等难题。针对传统相似性测度方法在高维空间出现的不适应性,提出了基于邻近集计算的光谱相似性测度方法。首先,采用邻域保持投影neighborhood preserving projections(NPP)算法对原始光谱数据进行降维处理,该降维方法可以很好的保留原始光谱数据非线性结构信息和数据点的邻域信息。然后,在光谱数据降维后的低维空间中,采用改进的邻近集计算方法,实现对近红外光谱数据的相似性测度。实验结果表明,基于邻近集计算的光谱相似性测度方法,有效的实现了光谱数据的相似性测度,在烟叶风格判定和品质分析方面有较好的应用前景,同时也为高维光谱数据相似性测度提供了一个良好的解决方法。 相似文献
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针对传统跟踪算法(如邻域法、传统的相关跟踪算法)只能跟踪海上或空中目标,不能跟踪复杂背景下目标的问题,提出了一种稳定快速跟踪复杂背景下目标的算法。该算法在传统相关跟踪算法的基础上进行改进,相关处理之前采用边缘检测、阈值分割等方法去除复杂背景,提取出具有特征的目标信息。在跟踪过程中,根据匹配的效果自动对模板进行刷新。给出了算法实现的硬件组成和程序流程图。实验证明对于传统算法无法稳定跟踪的目标,改进后的算法能够实现稳定跟踪。 相似文献
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Benjamin R. Lavoie Patrick M. Leung Barry C. Sanders 《Photonics and Nanostructures》2012,10(4):602-614
We show that waveguides with a dielectric core and a lossy metamaterial cladding (metamaterial-dielectric guides) can support hybrid ordinary-surface modes previously only known for metal-dielectric waveguides. These hybrid modes are potentially useful for frequency filtering applications as sharp changes in field attenuation occur at tailorable frequencies. Our results also show that the surface modes of a metamaterial-dielectric waveguide with comparable electric and magnetic losses can be less lossy than the surface modes of an analogous metal-dielectric waveguide with electric losses alone. Through a characterization of both slab and cylindrical metamaterial-dielectric guides, we find that the surface modes of the cylindrical guides show promise as candidates for all-optical control of low-intensity pulses. 相似文献
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A metal-dielectric mirror is shown as a simple solution for high-reflectivity coatings on cleaved-facet edge-emitting lasers, as well as a means to provide wavelength stabilization and spectral filtering. We show, through the use of a simple SiO2/Ti/Au coating, reflectivities better than 90% and a 25% reduction in the 30-dB linewidth of the output spectrum. Wavelength filtering and varying reflectivities are described as the result of multiple reflections and a coupled-cavity effect. 相似文献
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本文研究了在满足Concus-Finn条件时,微重力环境下内角沿容器轴线变化时的毛细驱动流问题,建立了变内角的毛细流动控制方程,获得了变内角流动的近似解析解,并与FLOW-3D软件的数值模拟结果进行了对比验证. 计算结果表明,随着时间的增大,近似解析解与数值解的相对误差越来越小,在6 s以后,相对误差不超过5%. 论文研究了不同结构参数对内角毛细流动的影响规律,得出液体前缘位置和液面高度均随内角、接触角、内角斜率和内角幂指数的增大而减小的结论. 在不同时刻,液体的液面高度随着时间的增大而增大,但在初始时刻存在一个常高度,该高度不随时间的变化而变化. 在空间流体管理时,可以根据本文的工作进行容器设计和选择适合的溶液.
关键词:
变内角
毛细驱动流
近似解析解
前缘位置 相似文献