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提出一种利用铅垂线轨迹法及高程结构信息约束的星载激光测高仪光斑内定位方法。在星载激光测高仪辅助立体摄影测量体制下,以激光回波中包含的高精度高程结构信息作为约束条件,在足印光斑内,配合立体图像匹配生成的数字高程模型,选取定位候选点,并通过铅垂线轨迹法优化定位候选点高程值,消除立体图像定位误差引起的高程误差,获取符合高程结构约束的一系列位置的三维坐标。试验结果表明,该方法能够实现大光斑星载激光测高仪足印内的定位,高程定位精度为0.16 m,平面定位精度与立体图像一致。 相似文献
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数码城市空间数据模型与可视化研究 总被引:9,自引:0,他引:9
提出了一种新的基于三维矢量图形、数字地面模型与数字地面正射影像相结合的数码城市空间数据模型,介绍了基于这一模型的软件平台原型-CCGIS,并对未来数码城市构建技术进行了分析与展望。 相似文献
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Detailed understanding of the processes which control river bank erosion requires high resolution information concerning temporal changes in bank morphology. This paper describes the successful use of digital photogrammetry to extract high resolution digital elevation models (DEMs) from terrestrial oblique stereopairs of rapidly eroding river banks, using the commercial software package Erdas Imagine. This software was developed for use with aerial photography and satellite imagery; problems relating to the use of oblique terrestrial images are discussed and solutions presented. Photography was acquired using semi-metric cameras, mounted on tripods and positioned about 15m from the eroding bank. Data for DEM point spacings of 20mm were obtained, with accuracies of approximately ±12mm in depth. Digital photogrammetry can permit faster analysis, provide better accuracies and involve less ground disturbance than conventional methods of monitoring river channel change. Most importantly, DEM generation is considered to be more useful than traditionally acquired points or profiles for landform monitoring strategies. 相似文献
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提高大比例尺地形图航测成图精度的测量方法 总被引:1,自引:0,他引:1
结合在白银市城区1∶500比例尺地形图航空摄影数字化成图,以及酒钢厂区1∶500比例尺现状图测绘的实际作业生产,介绍布设地面标志点进行航空摄影测量的作业方法,比较布设地面标志点进行航空摄影测量与常规航空摄影测量的成图精度。 相似文献
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Evaluation of Lidar and Medium Scale Photogrammetry for Detecting Soft-Cliff Coastal Change 总被引:3,自引:0,他引:3
Lidar and photogrammetry have both been evaluated for detecting shortterm coastal change using the Black Ven mudslide, Dorset as a case study. A lidar-generated digital elevation model (DEM) was obtained and initially compared with a DEM generated using available 1:7500 scale aerial photography and automated digital photogrammetry. The quality of these two data sets was assessed using a third DEM, derived using a total station and conventional ground survey methods. The vertical accuracies (rms error) of the lidar and photogrammetry were 0.26m and 0.43m respectively, although both data sets displayed a tendency to generate heights slightly lower than the elevation of the terrain surface. The quality of the two data sets was then assessed with respect to local slope angle. The accuracy of photogrammetrically derived elevations varied with slope and more so than in the case of lidar
From these basic tests, lidar has proved to be more accurate than photogrammetry for soft-cliff. monitoring. Further research is required to establish whether this trend is applicable to other data sets and specifically for photogrammetric data acquired using larger scale imagery 相似文献
From these basic tests, lidar has proved to be more accurate than photogrammetry for soft-cliff. monitoring. Further research is required to establish whether this trend is applicable to other data sets and specifically for photogrammetric data acquired using larger scale imagery 相似文献
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摄影测量数据库主要存储和管理数字地图成果数据,包括数字高程模型数据(DEM)、数字矢量地图数据(DLG)、数字影像地图数据(DOM)和数字栅格地图数据(DRG)。本文主要介绍了摄影测量数据库的设计、建立以及应用分析等内容。 相似文献
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仅用虚拟控制点的超大区域无控制区域网平差 总被引:2,自引:1,他引:1
利用光学卫星影像进行无控制测图是摄影测量追求的目标。针对超大区域无控制测图的需求,本文提出了一种以单景影像为平差单元,基于虚拟控制点的光学卫星影像超大规模无控制区域网平差方法。该方法利用待平差影像的初始RPC模型生成虚拟控制点,并将其作为带权观测值引入平差模型中以改善平差模型的状态,克服了在无控制点条件下平差精度不稳定、误差过度累积引起的网的扭曲变形等问题。为了验证本方法的有效性和精度,利用资源三号卫星获取的覆盖全国的26 406景影像进行区域网平差试验,并利用全国范围内分布的约8000个高精度控制点对平差后自动生产的DOM和DSM产品的几何精度进行验证。试验结果表明,平面和高程中误差均达到了4m以内,同时,区域网内部相邻影像之间的几何拼接精度优于1个像素,满足无缝拼接的要求。 相似文献
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ADS 80航空摄影测量系统的特点与应用 总被引:1,自引:0,他引:1
高立 《测绘与空间地理信息》2011,(6):212-214
仪器设备状况是航空摄影测量技术发展水平的标志。徕卡ADS 80基于航天传感器线阵扫描和全球定位系统、高精度的惯性导航定向系统(IMU)获取数字影像,利用该传感器进行航空摄影,不需经过扫描,就可以直接为数字摄影测量、遥感图像处理系统提供高分辨率的全色、真彩色、近红外数字影像,能够实现DLG数据的快速采集。与以往基于像对的... 相似文献
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航空数字摄影测量对林分立木测高及精度分析 总被引:6,自引:0,他引:6
为了解决以往森林调查手段需要在野外工作,并且比较耗费人力、物力与时间的问题,本文提出用航空摄影立体像对数字摄影测量的方法来估测林分立木高度。本研究利用两张廊坊市自然公园拍摄比例尺为1∶2500的航空像对,构建数字立体模型,在此模型上测量50株样木的高度,并结合实地用全站仪实测得出的数据进行精度的分析评价。结果表明:利用航空立体像对数字摄影测量立木高度,与全站仪实测数据相比差异不显著,两组数据呈线性正相关关系,精度达到93.96%,与林业调查上95%的精度要求较为接近。 相似文献
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无人机是继传统的航空摄影之后出现的一种新的数码航空摄影技术。它是利用无人机作为平台,用数码相机对地表进行航摄,以获取航空影像的一种方法。本文通过德惠市布海镇农村土地承包登记的试点工作,探讨了利用无人机航空影像制作1∶2 000比例尺DOM,并利用1∶2 000比例尺DOM进行农村土地承包登记的作业流程和技术方法。 相似文献
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Michael Clowes 《The Photogrammetric Record》2002,17(99):441-452
Digital photogrammetry as an aid to the process of conservation of the historic environment is now an established technique within English Heritage. Digital elevation models, orthophotographs and perspective views are becoming invaluable to the conservator as a record of a monument or site prior to some form of intervention or historical analysis. This paper reviews a range of projects where the various products generated by digital photogrammetry have been used and discusses some of the problems encountered 相似文献
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随着摄影测量技术的成熟和人们对摄影测量产品应用的要求不断提高,真正射影像在工程与人们生活中扮演越来越重要的角色。生成高质量真正射影像的关键在于如何获取高精度的DSM。目前修正和改善DSM误差的方法普遍存在费力费时、精度缺乏保证及任意性等问题。本文针对DSM精度的修正问题提出了一种新的方法,即基于投影影像的概念,将空间点位在投影影像上的投影轨迹线作为几何约束条件,直接对现有DSM的高程进行修正的方法。通过获取高精度的DSM,进而生成更为精确的真正射影像。本文通过理论推导、单点高程和多点高程修正试验,验证了提出的新方法直观简单,适用性强,具有一定的实际应用价值。 相似文献
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应用数字图像处理技术处理数字高程模型数据和与数字高程模型数据相结合的遥感信息 总被引:1,自引:0,他引:1
本文介绍了数字图像处理技术在处理数字高程模型数据和遥感信息与数字高程模型数据相结 合的综合分析方面的应用;说明了实现人工阴影和人工立体观察像对的方法的基本原理及其在处 理数字高程模型数据上的应用;介绍了为提高遥感图像的可解译性,把遥感信息与数字高程模型 相结合,制作遥感图像的人工立体观察像对和立体透视图像的方法技术。 相似文献
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《地理信息系统科学与遥感》2013,50(3):321-337
The launch of the Very High Resolution (VHR) sensor satellites has paved the way for further exploitation of the capabilities of satellite stereo imaging for many applications. The objective of this paper is to evaluate the level of accuracy that can be achieved by using stereo satellite images for different applications involving significantly different types of terrain. Three mathematical models for satellite sensor modeling are used: Rational Function Model (RFM), 3D polynomial model, and 3D affine model. Three stereo pairs of image datasets are tested from different satellites for different areas: (a) Indian Remote Sensing (IRS)-1D stereo images for topographic mapping and digital terrain elevation modeling for an area in Egypt; (b) IKONOS stereo images for highway alignments extraction in Toronto, Canada; and (c) IKONOS stereo images for topographic mapping and geometric parameter extraction for highway alignments in Hong Kong, China. The accuracy was evaluated by comparing the results of the data extracted using stereo satellite images and those extracted from conventional techniques, including Global Positioning System, field measurements, and aerial photogrammetry. The accuracy of the extracted features was found to be within a pixel-level. The results of this paper should be of interest to professionals from different disciplines exploring the use and accuracy of satellite stereo images for topographic and transportation applications. 相似文献
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G. Ducher 《The Photogrammetric Record》1989,13(73):111-126
A review of some recent activities undertaken by the Institut Géographique National, France (IGN) in photogrammetry is given in this paper, especially with regard to digital and space data processing, assessment of SPOT images and the development of new instruments and experimental map products. The main topics considered can be divided into three groups: aerial surveying, digital photogrammetry and space photogrammetry (including the possibility of further planetary missions). 相似文献