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在航空航天摄影测量领域中,利用画幅式像片本身的格网,可以精确地改正航摄像片的变形。本文采用相关系数匹配法和最小二乘匹配法实现了格网像片十字丝的自动量测。通过对画幅式航空格网像片的实验,证明该方法是有效的,达到了预期的目的。 相似文献
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数字影像匹配质量的一种自动诊断方法 总被引:1,自引:0,他引:1
利用欲诊断的影像匹配结果,由左、右影像自动生成数字正像片对和立体正身像片对,然后影像匹配方法自动量测其高程和高程改正值,从而自动诊断并自行改正原来影像的匹配结果,同时提供DEM、数字正射影像和立体正射像片对3种产品。 相似文献
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利用欲诊断的影像匹配结果(DEM),由左、右片影像自动生成数字正射像片对和立体正射像片对,然后用影像匹配方法自动量测其高程和高程改正值,从而自动诊断并自行改正原来影像的匹配结果,同时提供DEM、数字正射影像和立体正射像片对3种产品。 相似文献
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试验模型变形测量数码照相装置研究 总被引:4,自引:0,他引:4
针对矿山开采沉陷相似材料模型试验的特点,提出适合小变形体高精度位移测量的普通数码照相方法,通过在测点周围设置独立的控制格网并进行单点数码照相来获取模型测点的变形量,最后用试验验证该方法的实用性。 相似文献
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提出一种利用POS提供的影像定向参数辅助区域航空摄影测量中航带间影像自动转点方法。首先,对航带内影像采用金字塔影像匹配策略寻求同名像点,以获得航向间影像连接点的精确像片坐标;然后利用POS提供的影像定向参数预测航带间的影像连接点。再通过对相邻航线间待匹配窗口影像的几何变形改正,在由POS数据辅助建立的核线几何条件约束下,直接在原始影像上找寻同名像点;最后经最小二乘匹配使影像匹配结果达到子像素级精度。试验表明,将POS数据引入航带间的影像自动转点中,不但可以简化影像匹配过程、提高自动化水平,而且较常规影像匹配方法可以提高航带间自动转点的成功率34.0%,并节省76.7%的CPU耗时。 相似文献
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本文描述了一种关系,它使我们能够确定某一张像片上一个三维目标影像是否与另一张像片上一个目标的影像相匹配。这种影像匹配算法要求在两张像片上有9个同名像点的量测值,它仅依赖于像点坐标,而无需知道物方空间坐标或两摄影机的内外方位元素。该关系可以用于变化检测或分类,而且,当两张像片的透视中心存在较大差异时,这种方法特别有用。该研究的副产品是“核线方程”,它在影像的自动搜索和相关算法中很有用处。 相似文献
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一种综合利用像方和物方信息的多影像匹配方法 总被引:3,自引:1,他引:2
提出一种综合利用像方和物方信息的多影像匹配方法.首先对各原始影像采用3×3像元平均法生成4层金字塔影像,并在最高层金字塔影像中计算各搜索影像与基准影像的初始视差;然后从第3层金字塔影像开始进行基准影像与各搜索影像的匹配,并对各立体像对的匹配结果进行物方融合,剔除部分误匹配点,获得较精确的物方空间信息,以用于下一层金字塔影像的匹配.此过程融入带几何约束条件的相关系数法匹配和整体松弛法匹配策略;最后通过对某地区一组大重叠度数码航空影像的匹配试验,证实该方法的有效性.通过检测所生成的DSM精度,表明相对于传统的双片影像匹配方法,多影像的匹配可以有效剔除误匹配点并显著提高影像匹配的成功率. 相似文献
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基于普通数码相机的核线相关方法 总被引:2,自引:0,他引:2
用普通数码相机获取数字影像具有一定的优势,但由于普通数码相机是一种非量测相机,其数据处理需要特殊方法,介绍了一种适合普通数码相机进行核线相关的方法,实验数据表明该方法是可行的。 相似文献
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A novel method for multi-image matching by synthesizing image and object-space information is proposed. Firstly, four levels
of image pyramids are generated according to the rule that the next pyramid level is generated from the previous level using
the average gray values of the 3 by 3 pixels, and the first level of pyramid image is generated from the original image. The
initial horizontal parallaxes between the reference image and each searching image are calculated at the highest level of
the image pyramid. Secondly, corresponding image points are searched in each stereo image pair from the third level of image
pyramid, and the matching results in all stereo pairs are integrated in the object space, by which the mismatched image points
can be eliminated and more accurate spatial information can be obtained for the subsequent pyramid image matching. The matching
method based on correlation coefficient with geometric constraints and global relaxation matching is introduced in the process
of image matching. Finally, the feasibility of the method proposed in this paper is verified by the experiments using a set
of digital frame aerial images with big overlap. Compared with the traditional image matching method with two images, the
accuracy of the digital surface model (DSM) generated using the proposed method shows that the multi-image matching method
can eliminate the mismatched points effectively and can improve the matching success rate significantly.
Supported by the National Natural Science Foundation of China (Nos. 40771176, 40721001). 相似文献
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详细探讨了多测量手段集成的吴山石佛院造像数字化测绘项目的具体作业流程和关键技术,建立了石佛院精细、准确的数字化档案。针对石佛院造像表面特征复杂、数据海量、跨度大、测站多等特点,提出基于闭合导线整体平差分配模型的三维激光扫描数据配准方法,通过序列拼接、坐标转换、整体匹配和数据统一化来实现大场景、多视点和三维点云的全局配准。 相似文献
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Digital Photogrammetry and Microscope Photographs 总被引:1,自引:0,他引:1
The feasibility of applying commercial digital photogrammetric software to the measurement of small objects photographed through an optical microscope has been examined. The objects, about 20 mm across, were photographed using a 35 mm film camera (at the lowest magnification setting of the Olympus microscope) giving photographs at a scale of 2:1. The photographs were then scanned before processing with the VirtuoZo digital photogrammetric system. Various problems needed to be overcome, some due to the limited options available with the highly automated digital system which was not designed for such measurement tasks. The unusual image scales, the uncommon pixel sizes and the unconventional and uncertain imaging geometry, all impeded immediate photogrammetric implementation. Photographic problems with the microscope were also faced, as with all microscope photogrammetry. Creating control points and independently assessing the accuracy of results at these scales were also difficult operations, but an analytical plotter was utilized for both these purposes and to verify the imaging geometry. Once such problems were overcome, image matching proceeded well and an accurate DTM could be created successfully, provided that a suitably textured object was chosen. 相似文献
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三线阵CCD影像的像点自动匹配技术研究 总被引:3,自引:1,他引:2
目前国内针对三线阵CCD影像像点自动量测技术研究比较少,主要采用常规影像匹配方法进行处理。本文在分析众多匹配方法的基础上,根据三线阵CCD影像的特点,在立体环境下对三线阵CCD影像空三加密像点自动量测的方法进行研究。用实验的方法研究了基于金字塔分层动态窗口匹配运算的相关系数法在三线阵CCD影像像点立体匹配中的应用,最后通过三线阵CCD数字模拟影像试验,得出结论:采用金字塔分层动态窗口匹配运算的相关系数法是解决三线阵CCD影像空三加密像点自动量测问题比较有效的途径。 相似文献
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Effects of jpeg 2000 compression on automated dsm extraction: evidence from aerial photographs 总被引:1,自引:0,他引:1
This paper evaluates the effects of JPEG 2000 compression on automated digital surface model (DSM) extraction, using the area-based matching technique. Two stereopairs of aerial photographs, which have different photo scale, pixel size, and topographic type, are used as the images for the experiments. In the experiments, the DSM generated from the uncompressed image is set as the reference, and the elevation accuracy is computed for a range of compression ratios (2:1 to 100:1). The results show that the employed indices of image quality based on the JPEG 2000 compression are clearly superior to the commonly used JPEG compression technique—especially for high compression ratios. However, the elevation accuracy varies with the compression ratios. Also, JPEG 2000 compression does not have a significant influence on the percentage of the successful matching rate. In addition, a near linear fall-off is observed in extracted DSM accuracy with increasing compression ratios. 相似文献
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D. Rosenholm 《The Photogrammetric Record》1987,12(70):493-512
The effect on accuracy resulting from some changes to the conventional least squares matching method is investigated. Parallaxes computed automatically with matching methods have been compared with manual measurements made in a stereocomparator. Examples have been taken from both large and small scale aerial photographs and from close range images. Different linear geometric and radiometric parameters have been used as additional unknowns. The use of data snooping in digital matching with the least squares matching method has also been investigated. The results show that the introduction of additional affine parameters has a positive effect on the accuracy when the window size is larger than 30 × 30 pixels. The use of the data snooping technique is promising. The best precision obtained was between 10 pm and 15 μm, expressed as radial root mean square deviation, corresponding to approximately half a pixel. Gross error detection is possible to a large extent with photographs of good image quality. 相似文献