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This paper proposes a novel infrared small target detection method which is composed of two stages. The first stage is implemented by line-based reconstruction for suppressing the background clutter, and the second stage is induced by information entropy for further standing out the targets. Compared with the state-of-the-art approaches, the proposed approach is able to achieve better performance in terms of efficiency and accuracy. 相似文献
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遥感图像匹配是图像校正、拼接的基础。由于遥感图像特征相似度大,重叠区域小,遥感图像对匹配算法的要求更高。本文首先从特征检测、特征描述和特征匹配三个方面,比较了SIFT算法和SURF算法在计算速度和准确度方面性能,然后研究了算法对遥感图像重叠度、度量距离的要求,并针对SURF算法对特征方向误差敏感的特点,提出一种oSURF算法;最后利用卫星1A级条带遥感图像分析各个算法优劣性。测试结果表明,相比于SIFT算法,SURF算法计算速度为SIFT的3倍,需要的图像重叠宽度仅为1.25倍描述向量尺寸,而在保证同样匹配率的情况下,SIFT算法则需要图像重叠宽度为1.5倍描述向量尺寸。本文提出的oSURF算法在保证计算速度的同时,准确度相对于SURF算法提升5%~10%,因此,oSURF算法更适合1A级条带遥感图像的拼接。 相似文献
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A method of contrast enhancement of optical coherence tomography (OCT) images based on least squares fitting and histogram matching is presented. Several different functions are adopted as the probability density functions of the gray levels to fit the normalized histogram of an OCT image and histogram matching is used to enhance the OCT image automatically. The effectiveness of the method is proved by the experimental results. 相似文献
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韩广良 《中国光学与应用光学文摘》2011,(5)
介绍了一种通过提取红外与可见图像高频信息形成矢量模型的方法,该模型可用于可见和红外两种不同波段相同场景图像的配准。分析了红外与可见图像的共同特性,即边缘高频特性,并在作为模板的图像中提取这类高频信息。利用人工干预的方法形成矢量模型,该矢量模型可通过实时姿态信息进行实时三维变换,并重新投影为二维图形,据此可在另一图像中进行特征搜索,达到两者匹配的目的。利用实际数据进行了实验分析,结果显示,利用本文算法提取的矢量模型,经变换后能可靠地实现异源目标自动识别;实验证明此方法有效可行,并可推广应用于各种异源图像间的自动目标识别和配准处理。 相似文献
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某型运输机试飞纵向短周期等效拟配中在两个问题,一是纵向杆输入时长较长,频域辨识时高频段结果较差,二是在高阶电传飞机等效拟配时选择单拟配还是双拟配的问题,为了解决这两个问题,提出了时域辨识方法和对比分析传统机械式飞机和电传飞机试验数据方法;飞行试验数据处理结果表明,对于输入时间较长的试验动作,时域辨识效果较频域辨识好,使用时域和频域辨识结合的方法,大大提高了试飞数据的适用性;通过比较传统机械式飞机和现代电传飞机的试飞数据及拟配结果,发现高阶电传飞机必须使用双拟配方法才能更全面评价飞机特性;文中提出的辨识方法和分析方法很好地解决了某型运输机等效拟配中遇到的问题,可供其他电传飞机飞行试验参考。 相似文献
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本文用合振荡的原理对太电换能器的匹配问题进行了分析,提出了一种关于匹配的新概念-动态匹配,强调了效率在匹配中的重要性。 相似文献
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We present simultaneous phase matching of optical parametric oscillator (OPO) and difference frequency generation (DFG), using a noncollinear interaction in periodically poled crystal with single grating. Selecting proper grating period Λ and titled angle ξ between the grating vector G and the optical axis of crystal, the noncollinear scheme provides double phase matching solutions over continuous regions of the midwave infrared spectrum. At certain wavelength regions, for DFG process the group velocities between interaction pulses are matching and the phase matching bandwidth reaches maximum. Selecting the different grating period, the broadband midwave tuning and better gain spectrum can be obtained at different wavelength range. For the certain period grating the conversion efficiency is higher. Hence, using the double phase matching configuration, the broadband tunable midwave infrared wave can be produced in single grating. But the configurations have a relatively narrow angular bandwidth. 相似文献
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The complex frequency scaling property of Fourier transforms may be very effective for the determination of exact image rotation angle in application areas such as defense, manufacturing agriculture and commerce. In this paper, we exploit the complex frequency scaling property of Fourier transform to determine the exact angle of rotation of a target image with respect to reference image. We also investigate the validity of the developed algorithm using occluded target images. Further, we extend our algorithm to differentiate between different but similar rotated target images. We use both gray scale and DARPA's moving and stationary target recognition program's synthetic aperture radar images to validate our algorithm. 相似文献
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衍射光栅位相拼接的计算分析 总被引:2,自引:0,他引:2
从光学远场衍射的原理出发 ,研究了两块具有完全相同参数的衍射光栅间相互拼接时不同的位相与谱线强度变化的特性关系 ,建立了相应的数学模型 ,并利用计算机进行了模拟计算。计算的结果表明 :拼接出的光栅比其中单一一块光栅在增加了光强的同时也提高了分辨率 ,为通过采用拼接方法来获取大面积光栅提供了理论依据。 相似文献
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In this paper we introduced a kind of real-time image matching navigation algorithm based on ORB which can meet the requirement for high speed aircraft. We combined image matching with INS to fix the accumulative error of INS and get high accuracy position data of the aircraft. In order to improve the accuracy and robust of system, we used SIFT feature as a supplement of ORB and introduced the Kalman filter to optimize the output of image matching and INS. Based on maneuverability law, we did wrong point deleting with RANSAC. Finally, we designed a software system to simulate the image matching/INS navigation system. From the result of experiments, we can draw a conclusion that the algorithm has good real-time performance, play a good matching effect and get high accuracy position value. 相似文献
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发现经典非线性三阶驻波、短峰波解并不满足其所必须的波幅方程,这势必要影响与这些经典理论密切相关的现代短峰波理论的发展.基于此,提出了一套消除这种解与方程不相匹配的理论判据,从而可充分保证最终所得之解的内在和谐性和正确性.
关键词:
匹配解
理论判据
驻波
短峰波 相似文献