共查询到19条相似文献,搜索用时 125 毫秒
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卫星在轨颤动检测对CCD相机成像质量检测具有决定性,对图像应用潜力也是决定性的。利用快速小面阵CCD获取图像序列,提取任意时刻的参考图像与颤动图像进行SIFT初定位,利用RANSAC剔除SIFT位存在的粗差,结合图像运动模型,解算颤动状态参数。通过实验论证,此种方法检测在轨颤动是可行的、有效的。 相似文献
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环境与灾害监测预报小卫星星座(环境一号卫星,HJ-1A/B)自发射以来,在环境监测、灾害评估、土地资源调查等领域发挥了重要的作用。但是HJ-1A/B卫星CCD图像的2级产品(HJ-1 CCD图像)几何精度低,实际应用中需要进行几何精校正。HJ-1 CCD图像具有宽覆盖、大视场角、几何变形复杂的特点,几何精校正难度大。针对该问题,本文提出了一个以Landsat TM全球拼接图像为基准,基于Forstner算子和模板匹配的分层配准方法。该方法使用分层匹配获得的大量高精度且分布均匀的控制点构建Delaunay三角网,有效地解决了HJ-1 CCD图像的几何精校正问题。在配准技术研究的基础上,研发了HJ-1 CCD图像几何精校正系统,系统具有全球HJ-1 CCD图像的自动批量处理能力。实验结果表明,本文提出的几何精校正方法精度高,实现了环境星图像的自动批量处理。 相似文献
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本文提出一种利用经纬仪竖盘自动归零指标同时进行照准部旋转正确性和水准器格值检验的方法。这个方法也适合于一般具有竖盘符合水准器的经纬仪。 相似文献
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提出了一种利用天文观测手段获取的CCD图像序列对空间碎片进行自动识别和追踪的方法。该方法采用计算机图像处理、图像识别与分析和计算机视觉等相关技术,自动识别出每幅CCD图像中的空间碎片以及背景恒星等空间目标,并定量计算其有关特征;然后根据空间碎片移动较快的特点,在CCD图像序列中结合基于Snake模型的主动轮廓追踪和特征相似性比较两种方法,对其中出现的空间碎片目标进行自动识别和追踪。实验结果显示,该方法能准确地对空间碎片目标进行自动识别和追踪。 相似文献
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通过加载快速小面阵(charge-coupled device,CCD)获取成像图像序列,对参考图像和模拟颤振图像进行匹配(scale invariant feature transform,SIFT),剔除粗差(random sample consensus,RANSAC),结合成像运动模型,解算卫星在轨颤振像移量.通过基于IKONOS卫星数据的模拟实验,证明该方法对于检测在轨颤振是可行的. 相似文献
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为了提高空间CCD相机中数字视频图像信息的传输带宽,增强图像传输抗电磁干扰能力并提高光纤链路的整体性能,开发了应用于大视场空间相机的数字视频图像信息高可靠光纤传输系统。首先,根据CCD成像单元特点和相机在轨工作环境得出了传输系统的输入速率,在此基础上并结合CCD视频处理结构设计并实现了9通道CCD图像数据光纤并行传输系统。然后,阐述了系统设计思想,并说明了高速串化器和光模块的设计理念。接着,提出了(16,8)纠错编码算法,阐述了该算法思想和实现电路。最后,在XX-X空间多光谱相机样机的传输系统上进行了试验验证。实验结果表明:该传输系统图像传输正确、工作稳定、可靠性高、实时强、无误码,单路有效数据率达到2.44Gbit/s。(16,8)纠错编码算法纠错能力强、易于硬件实现、占用资源少。纠错算法在3043Byte内可以纠正191bit错误。该传输系统满足了空间相机图像传输的要求。 相似文献
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航天线阵推扫CCD图像在获取、传输过程中存在图像模糊的现象,而MTF是评价CCD图像质量的最可靠指标。为了改善图像质量,通过分析影响MTF的主要因素,提出基于系统模型的MTF补偿方法:首先建立系统模型,提出模型参数的估计方法,然后结合约束最小二乘算法复原图像。在仿真实验中,模拟图像的模糊和加噪过程,利用MTF模型复原图像,并评价MTF补偿图像质量,定量分析模型参数估计误差对图像复原结果的影响。实验结果表明:基于系统模型的MTF补偿方法能够有效而简便地复原图像,提高图像质量。 相似文献
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Metric Exploitation of still Video Imagery 总被引:1,自引:0,他引:1
The development of still video CCD cameras with digital image storage has made feasible the concept of offline, single sensor vision metrology. This paper reports on practical evaluations of such a system for dimensional inspection of aircraft tooling and for structural monitoring for large scale engineering. A further application of still video technology for low altitude aerial mapping is also reported. In each case a Kodak DCS200 camera has been employed for the photography in order to take advantage of the relatively high sensor resolution and adequate on-board image storage capacity. Aspects of the measurement operations, which yielded object space accuracies to 1:80 000 in the industrial measurement projects, are discussed and the results analysed. 相似文献
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GE Renyan Doctoral Candidate School of Information Engineering WTUSM Wuhan China 《地球空间信息科学学报》1998,(1)
With the help of CCD images,the realization of high precision po-sitioning and measurement has become the basic standard for machine vision andreal time photogrammetry systems.However,deformation and other sorts ofdegradation occurring during transmission are major limiting factors of the preci-sion attainable with most current CCD cameras and frame grabbers.So a preciseradiometric and geometric transmission of images from CCD sensor to memory is afundamental aspect of CCD camera calibration.The geometric calibration system,which uses some image processing algorithms of the CCD camera based on the re-searched and developed system is discussed.The reliability and validity are alsodiscussed.The experimental results for the calibration of the CCD array will betaken as an important quality index for CCD evaluation. 相似文献
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介绍了线阵CCD和MCS98单片机组成的光电尺寸测控系统。本系统既可用于汽车标准螺钉生产线上的非接触动态检测与控制,也可用作其他工业尺寸测控系统。实验证明了系统的可行性。 相似文献
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G. R. Hoffman 《The Photogrammetric Record》1995,15(86):205-216
The use of digital imagery, acquired through charge-coupled devices (CCDs) either by the scanning of hard copy film or direct capture through the use of a CCD camera, has fundamentally changed the photogrammetric environment. In order to fully exploit these digital image data, the photogrammetrist must employ system design, implementation philosophies and processing methodologies different from those of traditional film based photogrammetry. It is now possible for these new photogrammetric systems to be operated from low cost, high performance PC and Macintosh class commercial hardware, using vendor supplied software for user developed applications. This paper explores lessons learned and experiences gained from low cost, digital photogrammetric system development and CCD image exploitation. Examples and discussion presented in this paper include: (1) integration of user developed applications with commercial hardware and software; (2) user interface design; (3) validation of processing algorithms within the digital image domain; (4) system calibration; (5) digital image data handling, management and storage; and (6) image data compression. The film based photogrammetric system provides the point of departure to digital photogrammetry. Technical knowledge, system design and implementation and CCD image exploitation provide the experience. 相似文献
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将CCD引入放大率法焦距测量系统中,把CCD当作一把精度很高的"尺子"取代读数显微镜进行"读数",形成透镜焦距的CCD图像测量系统,使焦距测量的光电自动化成为可能。 相似文献