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1.
Three authors, representing commercial, educational and governmental photogrammetric organisations, report on their initial uses of analytical plotters.  相似文献   

2.
本文介绍了一种高效的基于摄影测量数据库的数字测图系统,该系统由数据采集、图形编辑和处理、绘图数据处理以及作为主体的数据库管理等四个子系统组成。用户可在国产解析测图仪APS—1和经过数字化改造的模拟测图仪器上进行数据采集,通过交互式图形编辑和摄影测量处理以形成1:5万摄影测量数据库数据,并输出线划地形图,具有对该数据库数据的检查、验收功能。此外,本文还研究了等高线内插的若干算法,形成了较为实用的等高线内插软件包。  相似文献   

3.
Using a multidisciplinary project studying surging glaciers in Svalbard as a reference, this paper examines some of the ways in which photogrammetry can be used as a research tool by glaciologists. Photogrammetric compilations of two of the glaciers under study were produced from 1990 aerial photography. Photogrammetry was regarded primarily as a source of digital elevation models in this project, rather than as a cartographic tool. Problems encountered in applying photogrammetry to the arctic terrain are considered and a methodology devised to ameliorate these problems by maximizing the available data is described. The results of the photogrammetric work are presented and difficulties in quantifying the accuracy of the photogrammetric data are examined. Examples of the ways in which the photogrammetrically derived digital data have been used for glaciological analysis and visualization are discussed.  相似文献   

4.
Abstract

The equipment available for numerically controlled plotting and draughting is reviewed and certain devices described in some detail. Several systems suited to the digitising of cartographic material exist, while the available plotters may be classified broadly into three categories—those derived from surveying and photogrammetric practice, those associated with computer technology and a group designed substantially for cartographic applications. Finally the various input and output devices associated with cartographic digitising are discussed with special emphasis on their storage capacity, speed of operation and economy.  相似文献   

5.
论述一个由数字化画幅式像片(或数字影像)用数字摄影测量系统生成的DEM数据精度的确定方法。该方法的特点是只使用数字摄影测量系统的观测,避免了其它测量系统(如解析测图仪)的影响。通过在数字视频测图仪(DVP)上所作的大量实验证明本文中设计的方法是普遍实用的。实验结果表明,影响DEM数据的精度的主要因素是像元大小。  相似文献   

6.
The Department of Geomatics and the Regional Centre for Innovation in Engineering Design in the University of Newcastle upon Tyne collaborated in a project to produce precise measurements for use in the fabrication of the body of the "Angel of the North" sculpture. This 20 m high edifice, by the sculptor Antony Gormley, is located adjacent to the A1(M) in Gateshead, Tyne and Wear.
This paper reviews the photogrammetric reverse engineering work carried out on a 1:10 scale plaster maquette of the "Angel of the North", which is a life-size model of the sculptor's body without any arms. The three dimensional measurements of the maquette, made by analytical photogrammetric techniques, were then processed to produce a fully functional three dimensional CAD model from which the dimensions needed by the fabricating company, Hartlepool Steel Fabrications Ltd., could be extracted. Additionally, the VirtuoZo digital photogrammetric software package was used to investigate the potential of automated measurement for this type of work and the results were compared with those obtained analytically.  相似文献   

7.
This paper reports on an investigation into the suitability of the Kodak DCS Pro Back for use in close range photogrammetric measurement. The camera back, being used in conjunction with a medium-format non-metric camera, has been assessed with a view to using it for low- to medium-order photogrammetric work in architectural recording. Examinations centred upon the stability of the camera back with respect to the camera body and the effects of the removable infrared filter that is present immediately above the camera's focal plane. Ultimately the camera combination was deemed suitable for application in recording of this kind and is now in active use by the Metric Survey Team at English Heritage.  相似文献   

8.
As the performance of megapixel digital imaging systems continues to improve, the rapid growth of high-end consumer markets drives prices ever lower. When such cameras are married with emerging, desktop "photogrammetric" software packages, the close range photogrammetric community is faced with many new challenges and opportunities. The dramatic changes in the technological arena are matched by a rapidly changing business environment in which concepts such as "Partnering" and "Supply chain management" have become key themes. As organizations of all sizes seek to thrive within this new business landscape, there appears to be a willingness to think more flexibly about the client-supplier relationship and the sharing of risks and rewards. This, in turn, has encouraged the development of highly customized measurement solutions across a wide range of market sectors. In each of these solutions the emphasis is not on a generic photogrammetric product, but on a highly tailored system tightly coupled to existing workflows, and focused on the specific needs of the client. Such systems pose particular challenges to their designers, since they are frequently operated by users with relatively little photogrammetric background and yet must always meet the challenging requirement of producing an output which is "fit for purpose". Thus this paper hopes to show how novel megapixel imaging systems can be configured to deliver flexible measurement systems capable of millimetric level accuracy within the challenging engineering environments typical of the nuclear and process industries (hence the microsievert component of the title).  相似文献   

9.
Ordnance Survey experimental work has shown that colour film developed to a reversed positive image is best suited to the photogrammetric problems of large-scale mapping. Tests have shown no difference in accuracy between maps produced from colour photography and those produced from monochrome photography. The economy of using colour photography in this field has yet to he demonstrated.  相似文献   

10.
王任享 《测绘科学》2013,38(1):5-7,43
本文介绍了天绘一号卫星立项前的预先研究和试验工作、摄影测量研究历程框架以及关键的学术思想。EFP多功能光束法平差结果表明:无地面控制点目标定位精度达到工程技术指标,并与美国SRTM相对精度相当。此外,笔者还简要地介绍了国外主要传输型卫星无地面控制点摄影测量历程。  相似文献   

11.
谈大数据时代的“云控制”摄影测量   总被引:3,自引:1,他引:2  
张祖勋  陶鹏杰 《测绘学报》2017,46(10):1238-1248
在当今大数据时代,影像数据采集方式的多样化、高效化、便捷化产生的摄影测量影像大数据需要高效、自动与智能的处理。然而,作为传统摄影测量几何定位主要控制数据的外业控制点,其获取的复杂性与低效性仍然是制约摄影测量处理效率的关键因素。针对该问题,本文提出了"云控制"摄影测量的概念,以带有地理空间信息的数据作为几何控制替代外业控制点,通过自动匹配(或配准)获取大量密集的控制信息;并介绍了基于影像、矢量和LiDAR点云的3种"云控制"摄影测量技术;最后对"云控制"摄影测量的应用前景进行了展望并对其问题进行了讨论。  相似文献   

12.
This paper reviews the requirements and equipment for the photogrammetric restitution of digital data. Advances in computer technology have made it possible to process and display image data in very fast time; this has made real time movement of images on a display screen a reality and hence, together with stereoscopic viewing, a digital version of the analytical plotter. The necessary components are discussed and the implementations which have been made. The use of parallel processing for additional speed is also discussed and the alternatives of using standard workstations are considered. A system developed at University College London is described and some pointers to the future are provided.  相似文献   

13.
In the Preface to his book, The Four Faces of Fourcade, Clare Storrar (1990) wrote: "It is di.cult to appreciate the breadth and depth of Henry Georges Fourcade's intelligence and creative power. He was an intellectual giant, a phenomenon, whose theoretical and practical achievements have never received proper recognition. These were all the more remarkable because he began his original work on photogrammetry when science in South Africa was in its infancy, and he laboured alone far from libraries and other research facilities. His only higher academic training was in land surveying. He was adept in each of four sciences at various stages in his life, but, mainly because of his natural reserve, his reputation was highly compartmentalised. To foresters he was 'the most brilliant forestry officer of his time' to surveyors, he was exceptionally learned in theory and skilled in practice. Photogrammetry was a new subject, unheard of, except by a handful of scientists. In botany, which he took up seriously at the age of fifty-five, his work was highly regarded by leading botanists in South Africa and in Europe. All stood in awe of his extraordinary talent and ability. Some were frightened of him. But few were able—in fact, not even the best brains were wholly qualified—to grasp fully the tremendous intellectual stature and potential of this protean man."
This paper briefly describes the historic achievements of Henry Georges Fourcade, with the emphasis on his land surveying and, in particular, his photogrammetric contributions to science. The centenary of one of these, his proposal of a stereoscopic method of photographic surveying, occurs in October 2001.  相似文献   

14.
This paper describes work undertaken to measure deformation of a pavement within the Newcastle University Rolling Load Facility (NUROLF). Precise three dimensional measurements of the pavement have been produced from stereo-imagery taken with diVerent cameras, using both analytical and digital photogrammetric instrumentation. The photogrammetric measurements, and those from the existing system consisting of an array of linear voltage displacement transducers, have been compared with measurements produced using a digital level. Encouraging results have been achieved and photogrammetry has been shown to be capable of producing a similar accuracy to the existing system. There are many advantages associated with a photogrammetric survey but attempts to establish a permanent, automated photogrammetric system for the rolling load facility at a reasonable cost have so far been unsuccessful. It is anticipated that, with the falling cost of high resolution digital sensors, such a system will soon be possible.  相似文献   

15.
航测影像分辨率高、现势性强,采用航测影像进行送电线路平断面图的绘制是减少外业工作量,提高生产效率的主要手段。本文分析了航测平断面图高程误差产生的原因,提出了利用GPS RTK外业采集高程数据,提高航测平断面图高程拟合精度的方法。  相似文献   

16.
17.
非量测型相机检校及可靠性研究   总被引:2,自引:1,他引:1  
随着大面阵CCD技术以及数码相机的出现、应用和发展,数码相机开始应用于摄影测量生产,但是数码相机镜头畸变差很大,内方位元素无法直接量取,属于非量测型相机,这就使得数码相机无法直接在摄影测量中使用。文章通过对数码相机的检校和精度分析,说明了数码相机通过检校具有较高精度,并通过具体实践,证明了经检校的数码相机用于摄影测量是可行的。  相似文献   

18.
In the past few years the automation of digital industrial photogrammetric systems has increased dramatically. Due to digital image processing software, coded targets and automatic matching methods, a huge number of photogrammetric measurement tasks can be fully automated. In many cases a "one button click" is enough to provide the three dimensional co-ordinates of measured points without any manual interaction, immediately after acquiring the images. The technology of intelligent cameras is a logical step towards automated photogrammetric measurements. An intelligent camera, which has an integrated computer, analyses the image immediately after it is taken. This technology provides not only a much shorter processing time for the images but also more control over the measurement process just when it is needed, during image acquisition. This takes place in the form of real time feedback.
This paper describes the role of a digital intelligent camera in the automation of an industrial photogrammetric measurement system and gives an overview of existing automation techniques in industrial photogrammetry. As an example of an intelligent camera, the performance of the new INCA digital intelligent camera, developed and manufactured by Geodetic Services, Inc. (GSI) and distributed by Leica, is described.  相似文献   

19.
The paper discusses a method of photogrammetric control for engineering problems which relies on reciprocal observations between instruments. Since photogrammetric networks do not usually permit cameras to point at one another, it is proposed that at least one additional theodolite station be used to establish these observations. This results in directly measured space triangles; in a sense the photogrammetric task becomes a surveying problem. Potential advantages are a more efficient use of mixed photogrammetric and survey measurements, a stronger network geometry and a direct solution for the orientation parameters of the instruments. Special attention must be given to targeting the camera and theodolite stations.  相似文献   

20.
VC中COM的]Dispatch接口可使C++程序同VBA程序进行通信,从而完成对Microsoft Word的操作.文中以航测外业控制点信息表自动制作与填写为例,提出一种面向对象的Word自动化技术.  相似文献   

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