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YUAN Xiuxiao 《地球空间信息科学学报》2000,3(1):24-33
1 IntroductionAs is now well known, the high accurate point de-termination with airborne remOe sensing data hasalways ben one of the most fundaxnental prObletns..in aerial photOgrammtry. According to the princi-ple of the geOmtry reversal in photOgramrntry,the interior and exterior orientation elements ofaerial phOtOgraphs must first be known in order toreconstnJct the measuring stereo geometric medels.For the past 60 years, however, the interior orienta-tion parameters of carnera were main… 相似文献
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Xiuxiao Yuan Jianhong Fu Hongxing Sun Charles Toth 《ISPRS Journal of Photogrammetry and Remote Sensing》2009,64(6):541-550
In traditional GPS-supported aerotriangulation, differential GPS (DGPS) positioning technology is used to determine the 3-dimensional coordinates of the perspective centers at exposure time with an accuracy of centimeter to decimeter level. This method can significantly reduce the number of ground control points (GCPs). However, the establishment of GPS reference stations for DGPS positioning is not only labor-intensive and costly, but also increases the implementation difficulty of aerial photography. This paper proposes aerial triangulation supported with GPS precise point positioning (PPP) as a way to avoid the use of the GPS reference stations and simplify the work of aerial photography.Firstly, we present the algorithm for GPS PPP in aerial triangulation applications. Secondly, the error law of the coordinate of perspective centers determined using GPS PPP is analyzed. Thirdly, based on GPS PPP and aerial triangulation software self-developed by the authors, four sets of actual aerial images taken from surveying and mapping projects, different in both terrain and photographic scale, are given as experimental models. The four sets of actual data were taken over a flat region at a scale of 1:2500, a mountainous region at a scale of 1:3000, a high mountainous region at a scale of 1:32000 and an upland region at a scale of 1:60000 respectively. In these experiments, the GPS PPP results were compared with results obtained through DGPS positioning and traditional bundle block adjustment. In this way, the empirical positioning accuracy of GPS PPP in aerial triangulation can be estimated. Finally, the results of bundle block adjustment with airborne GPS controls from GPS PPP are analyzed in detail.The empirical results show that GPS PPP applied in aerial triangulation has a systematic error of half-meter level and a stochastic error within a few decimeters. However, if a suitable adjustment solution is adopted, the systematic error can be eliminated in GPS-supported bundle block adjustment. When four full GCPs are emplaced in the corners of the adjustment block, then the systematic error is compensated using a set of independent unknown parameters for each strip, the final result of the bundle block adjustment with airborne GPS controls from PPP is the same as that of bundle block adjustment with airborne GPS controls from DGPS. Although the accuracy of the former is a little lower than that of traditional bundle block adjustment with dense GCPs, it can still satisfy the accuracy requirement of photogrammetric point determination for topographic mapping at many scales. 相似文献
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J. G. Fryer 《The Photogrammetric Record》1983,11(62):203-208
A photogrammetric system that is suitable for shallow water detailed mapping at scales from 1:50 to 1:500 for coastal and harbour engineering projects is described. The results from tests using automatic 35 mm Canon cameras on an elevated platform to determine the accuracy of planimetric and depth co-ordinates are presented. The economic benefits of stereophotography through shallow water rather than underwater photography are discussed. 相似文献
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大范围倾斜多视影像连接点自动提取的区域网平差法 总被引：3，自引：3，他引：0
提出了一种大范围倾斜多视影像自动连接点提取和光束法区域网平差算法。首先利用POS数据对倾斜影像进行矫正并预测候选像对,使用SIFT特征进行影像匹配;然后利用并查集数据结构实现多视影像间连接点对应关系的快速确定;最后将POS数据和控制点数据作为带权观测值进行平差解算。选取3种典型的倾斜相机系统(组装轻量级倾斜相机、国产SWDC-5相机、微软UltraCam相机)进行了试验,结果表明,本文算法能够适应国内外流行的倾斜摄影系统,且一次性可处理的影像数目超过2000张;在相同条件下倾斜影像光束法区域网平差的整体精度优于传统垂直摄影情形,实际精度可以达到水平方向0.75 GSD,高程方向2.0GSD。 相似文献
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UAVRS影像空中三角测量实验研究 总被引：5，自引：0，他引：5
无人飞行器低空遥感系统(UAV Low Altitude Remote Sensing System简称UAVRS系统)适合于在阴云山区低空获取高分辨率垂直和倾斜影像,但获取的影像存在像幅小、数量多、基线短、重叠度不规则且倾角过大等问题,而这些问题,都是国内外现有的数字摄影测量系统面临的新问题。本文提出以带权观测值光束法平差解决UAVRS复杂影像区域网的空中三角测量问题的方法。其技术要点在于,从提高单模型定向的精度出发,以单模型定向元素为基础构建自由区域网,为带权观测值光束法平差提供有效初值。经试验表明,空三加密点的平面精度为0.386m,高程精度为0.525m,基本能达到1∶2000地形图测图的要求。 相似文献
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Following the success of the symposium held by the Photogrammetric Society on 31st March, 1987, a second one-day symposium was convened to give further support to the rapidly growing interest in the development of small format photography for aerial survey. This was held at Burlington House, London on 1st November, 1988. Over 70 people attended. Six of the papers are reproduced here, dealing with a range of topics including specifications for and navigation of small format aerial photography, the creation of digital terrain models from 35 mm photography, wildlife surveys in the Arctic and survey photography from model aircraft and tethered balloons. 相似文献
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近几年来,GPS/INS组合的导航系统——POS系统已逐步成熟,并应用于无人机飞控系统,虽然POS精度不是很高,但是其实现了影像外方位元素的直接获取,并且摆脱了传统摄影测量对大量地面控制点的严重依赖,方便了影像像控点的布设。同时,为了使成果DOM精度达到项目要求,少量控制点的布设仍不可避免,为此,如何合理选取困难地区像控点布设方案成为工程项目中急需解决的问题。为了获取针对困难地区的像控点合理布设方案,本文基于甘肃陇南地区土地确权项目,通过对测区无人机影像采用不同的像控点布设方案进行空三平差处理,分析正射影像图的平面精度情况来选取适合当地的布设方案。实验结果表明,在满足生产精度的前提下,适当放宽国家规范的像控点布设要求的同时,给出困难地形的像控点布设方案,能极大提高像控点测量野外作业效率,并且可以在其他测区推广使用。 相似文献
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由于大型牌式古建筑自身单体窄高、面饰构件灵活百怪,单一建模技术因自身数据采集的局限性,难以单方面建立全面的大型牌式古建筑三维模型电子档案。针对此问题,本文以桂北灌阳县月岭村月岭"孝义可风"牌坊为研究对象,提出了一种空地多数据互辅融合三维模型重建方式,以倾斜摄影与三维激光扫描为主,地面近景多视角拍照为辅的采集方案,重建完整精细的大型牌式古建筑文物三维模型电子档案,并完成了数据融合偏差验证、数据融合前后的模型完整性分析与精度对比评估。该方法可为大型牌式古建筑档案的建立提供新的思路,在文物保护方面具有广泛应用前景。 相似文献
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S. Piteri 《The Photogrammetric Record》1990,13(76):591-602
The effect of sweep positional distortion on the quality of images of panoramic photographs is evaluated for vertical, forward looking oblique and tilted panoramic photography. It is shown that an image motion compensation mechanism will not eliminate sweep positional distortion completely, and a residual displacement will exist, which is greater for image co-ordinates parallel to the central axis of the panoramic cylinder of the vertical and forward looking oblique photography. 相似文献
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G. H. Thomson 《The Photogrammetric Record》1988,12(71):595-603
The use of small format systems for aerial photography as an alternative to employing the more customary larger 230×230 mm format cameras continues to gain acceptance in a number of applications on the basis of the lower operating costs involved. The reduced costs and relative ease of operation with small format systems can attract unskilled operators who, by producing inferior photographic coverage, may delay the more widespread introduction of smaller systems for photo-interpretation and photogrammetric surveys of local sites. Anticipating the need for a flying and photography specification that would serve the needs of all interested parties, a series of laboratory trials were undertaken in conjunction with a literature review to quantify the comparative image quality performance of both large and small format systems. The spatial resolution of a typical small format system was assessed by photographing a low contrast resolution target using a collimator-based system and also by directly recording the target at a predetermined reduction scale. Comparative results between the two methods of evaluation are assessed and a comparison is made with the performance of larger format cameras. 相似文献
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《ISPRS Journal of Photogrammetry and Remote Sensing》1999,54(5-6):332-341
This paper deals with the orientation of three-line imagery which has been taken during the MOMS-02/D2 experiment in spring 1993, and during the MOMS-2P/PRIRODA mission since April 1996. The reconstruction of the image orientation is based on a combined adjustment of the complete image, ground control, orbit and attitude information. The combined adjustment makes use of the orientation point approach or the orbital constraints approach. In the second case, the bundle adjustment algorithm is supplemented by a rigorous dynamical modeling of the spacecraft motion. The results of the combined adjustment using MOMS-02/D2 imagery and control information of orbit #75b are presented. Based on the orientation point approach an empirical height accuracy of up to 4 m (0.3 pixel) is obtained. In planimetry the empirical accuracy is limited to about 10 m (0.7 pixel), since the ground control points (GCP) and check points could not be identified in the imagery with the required accuracy. Computer simulations on MOMS-2P/PRIRODA image orientation based on realistic input information have shown that good accuracies of the estimated exterior orientation parameters and object point coordinates can be obtained either with a single strip and a few precise GCP or even without ground control information, if a block of several overlapping and crossing strips with high geometric strength (q≈60%) is adjusted. 相似文献
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为提高无人机对地定位精度，必须对系统进行几何标定与补偿。首先进行了直接地理定位实验，检验系统在不经过任何标定时的直接地理定位精度；然后进行了自由网光束法平差实验，以验证无地面控制点时系统的定位精度；最后进行了POS辅助自检校光束法平差，对内方位元素变化、相机畸变、IMU安置角进行标定和补偿，并验证了系统误差补偿后的直接地理定位精度。实验结果表明，未经几何标定的无人直升机直接地理定位的精度可满足应急条件下测绘保障要求；少量地面控制点的辅助下定位精度远优于1:500比例尺地形图测图的要求，可用于常规测绘生产；系统误差补偿后，直接地理定位精度有明显提升:平面精度提高46.37%，高程精度提高62.49%；系统误差标定和补偿方法正确、有效，无人直升机具有很好的测绘应用前景。 相似文献
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Bias-corrected rational polynomial coefficients for high accuracy geo-positioning of QuickBird stereo imagery 总被引：1，自引：0，他引：1
Xiaohua Tong Shijie Liu Qihao Weng 《ISPRS Journal of Photogrammetry and Remote Sensing》2010,65(2):218-226
The rational function model (RFM) is widely used as an alternative to physical sensor models for 3D ground point determination with high-resolution satellite imagery (HRSI). However, owing to the sensor orientation bias inherent in the vendor-provided rational polynomial coefficients (RPCs), the geo-positioning accuracy obtained from these RPCs is limited. In this paper, the performances of two schemes for orientation bias correction (i.e., RPCs modification and RPCs regeneration) is presented based on one separate-orbit QuickBird stereo image pair in Shanghai, and four cases for bias correction, including shift bias correction, shift and drift bias correction, affine model bias correction and second-order polynomial bias correction, are examined. A 2-step least squares adjustment method is adopted for correction parameter estimation with a comparison with the RPC bundle adjustment method. The experiment results demonstrate that in general the accuracy of the 2-step least squares adjustment method is almost identical to that of the RPC bundle adjustment method. With the shift bias correction method and minimal 1 ground control point (GCP), the modified RPCs improve the accuracy from the original 23 m to 3 m in planimetry and 17 m to 4 m in height. With the shift and drift bias correction method, the regenerated RPCs achieve a further improved positioning accuracy of 0.6 m in planimetry and 1 m in height with minimal 2 well-distributed GCPs. The affine model bias correction yields a geo-positioning accuracy of better than 0.5 m in planimetry and 1 m in height with 3 well-positioned GCPs. Further tests with the second-order polynomial bias correction model indicate the existence of potential high-order error signals in the vendor-provided RPCs, and on condition that an adequate redundancy in GCP number is available, an accuracy of 0.4 m in planimetry and 0.8 m in height is attainable. 相似文献
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Bundle triangulation is an efficient tool for spatial point determination in architectural photogrammetry. All the information available in image and object space may be introduced in a combined adjustment yielding high precision and reliability. Camera calibration performed simultaneously with the object restitution process enables the application of convenient and flexible imaging systems based on professional photographic technology. Thus the survey of monuments can be carried out rapidly with a minimum of personnel and equipment. The photogrammetric recording of the basilica of San Francesco in Siena is presented as an example of the application of this survey procedure. The field work was accomplished in a few days. The equipment used consisted of a partial metric camera, an engineering theodolite and a tape. The bundle adjustment results gave spatial object co-ordinates with a r.m.s.e. of ± 15 mm for a point. 相似文献
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像点偏移是影响光束法区域网平差结果精度的主要因素之一。克服平差过程中像点偏移的影响,以提高区域网平差精度,一直受到业界高度重视。当前,克服像点偏移的常规做法是借助特定的参数模型对其进行描述,构建基于附加参数模型的自检校光束法区域网平差模型,在区域网平差的同时求解引入的参数,进而实现对系统误差的补偿。Bauer模型、Ebner模型、Brown模型、光学畸变模型是现有算法中描述像点偏移的常用模型。为了对上述4种模型的系统误差进行验证,本文首先在经典的光束法区域网平差模型基础上分别设计了与4种模型相对应的自检校光束法区域网平差模型,并予以编程实现;然后通过实例对上述4种模型的算法运行结果进行了验证、比较及分析。试验结果表明,Ebner模型和Brown模型的引入可有效提高光束法区域网平差的精度;Bauer模型的引入对小型区域网平差精度的提升更加有效;光学畸变模型的引入对区域网平差结果的精度提升作用相对较小。 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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基于已知定向参数影像的光束法区域网平差 总被引：1，自引：1，他引：1
从自检校光束法区域网平差模型出发,建立了利用同一地区已知定向参数的影像解求新获取影像外方位元素并进行目标定位的数学模型。以此为基础,对来自某地区相隔两年的三期不同摄影比例尺航空影像两两组合地进行联合光束法区域网平差。结果表明,当两期影像比例尺相近时,所解求的新影像外方位元素和加密点坐标精度基本达到常规光束法区域网平差的精度;当两期影像比例尺不同时,利用已知定向参数的大比例尺影像解求出的小比例尺影像的外方位元素和加密点坐标可满足现行规范精度要求,利用已知定向参数的小比例尺影像去解求大比例尺影像的外方位元素和加密点坐标精度明显下降且不可用。本文的研究证实,就同一地区的多时相航摄影像而言,利用已知定向参数的影像进行新影像的定向方法是可行的。 相似文献
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Normally, regular surfaces of architectural or archaeological interest can be accurately mapped with single-image techniques. Whenever possible, such surfaces are developed digitally, or they are presented as suitable cartographic projections. This paper describes the raster development of two large towers, one conical and one cylindrical, with heights of 19m and 12 m, and diameters of approximately 10m and 8m, respectively. The towers, dating from circa 300 BC, are situated on Greek islands and are accessible only on foot. The first tower was imaged from its surrounding hills with several lenses, including powerful telephoto lenses. The other tower was recorded from up to 9m above ground level by means of a modified fishing rod carrying a lightweight 35mm camera. All the non-metric photographs, taken at a negative scale of approximately 1:350 which allowed an overall accuracy of 3 cm to 4 cm to be achieved, were developed digitally and then mosaicked. The raster products are described and discussed. 相似文献
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《测量评论》2013,45(60):221-227
AbstractIn a previous article in this Review, the writer endeavoured to show that chains of minor triangulation could be adjusted by plane rectangular co-ordinates ignoring the spherical form of the earth with little loss of accuracy, provided that the two ends were held fixed in position. It was demonstrated that the plane co-ordinates produced by the rigorous adjustment between the fixed starting and closing sides, differ by only a comparatively small amount from the projection co-ordinates produced by a rigorous adjustment on the Transverse Mercator projection. The saving in time when computing by plane co-ordinates as opposed to rigorous computation on the projection by any method will be apparent to any computer with experience of both methods. 相似文献