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Digital photogrammetric techniques have opened fresh horizons and have enabled photogrammetry to become a more user friendly tool for a wide range of applications. However cost remains a critical issue, because new digital photogrammetric workstations and their related software are considered expensive. This paper examines the problem of digital rectification and presents low cost solutions involving the use of commercial off the shelf software packages, which include graphics and painting software, image processing tools and a CAD system. Additionally, specially developed software performing vector rectification is described and discussed. All the packages have been used for rectifying digital images and the results are presented. An attempt is also made to assess the accuracy and reliability of the results. Finally, several alternative digital products are presented, mainly concerning the use of the methods described in the restitution of cultural monuments. 相似文献
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Manuel A. Aguilar Fernando J. Aguilar Francisco Agüera 《The Photogrammetric Record》2005,20(112):335-350
Generating maps of small areas using conventional aerial photography is of great interest for small engineering firms. The main problem is the high cost of the sophisticated digital photogrammetric workstations usually employed. In this paper, a low-cost close range photogrammetric software package is used to measure the three-dimensional coordinates of points on the land surface from a photogrammetric flight at a scale of approximately 1:5000. Furthermore, the influence of the type of scanner used to digitise photographs (consumer-grade or photogrammetric scanner), the resolution of the digital images and the number of control points required are examined. The root mean square errors obtained at the check points, using a low-cost close range software package, scanning aerial images with a photogrammetric scanner and 24 ground control points, were around 116 mm for X and Y coordinates, and 191 mm for Z. These levels of accuracy allow the generation of planimetric maps at a scale of 1:1500 and topographic maps with a contour interval of around 1 m. When the images were scanned with a consumer-grade scanner, the root mean square errors were around 150 mm for X and Y, and 271 mm for Z. 相似文献
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首先阐述了城市3维仿真模型的重要意义,然后分析了3维仿真模型的数据生产方法和建模流程。本文着重对如何运用数字摄影测量工作站采集建筑的特征线,结合Max Script语言快速制作出3维建筑模型的方法进行了初步探索。 相似文献
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I. J. Dowman 《The Photogrammetric Record》1990,13(75):331-345
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
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A. S. Walker 《The Photogrammetric Record》1997,15(89):657-664
The revolution promised by digital photogrammetry is dependent on extensive, successful automation at many stages of the production process. The progress of automation is uneven. Digital cameras are not in widespread use. Scanners are available which include roll film transports and automated orientation, but set up for optimum tonal transfer remains interactive. Extensive automation of several operations on digital photogrammetric workstations, such as generation of digital terrain models, orthophotographs, mosaics and perspective scenes, contrasts with feature extraction, where robust products lag behind success in research. Progress towards practical automation to assist, but not replace, the human operator is significant, however, and examples are given from the Leica-Helava systems. 相似文献
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主要介绍JX-4C DPW微机数字摄影测量工作站与VirtuoZo全数字摄影测量系统这两款测绘软件在立体测图方面各自的特点以及在实际生产当中各自的优势与缺陷。同时介绍了这两款软件与MicroStation进行联机测图的应用方法。 相似文献
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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
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提出了利用3个不共线的控制点对相机外参数近似值进行快速求解的一种方法.利用3个控制点与其像坐标间的几何关系求得3个控制点在摄站坐标系下的坐标;由控制点的已知控制坐标与求得的摄站坐标系下的坐标,进一步求得两坐标系的转换参数的初值;通过解析法或光束法对相机外参数用初值进行精确标定.并通过一组模拟数据验证了该方法的正确性. 相似文献
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多摄站系统质量分析及其法方程病态现象的克服 总被引：2，自引：0，他引：2
本文介绍了一个多摄站（全方位）摄影测量系统，它适宜于近景摄影测量灵活的构网形式，包括全方位摄影，文中分析了多摄站摄影测量网平差的精度和可靠性，并介绍一种该系统试用的克服法方程病态现象的新方法。 相似文献
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J. Dold 《The Photogrammetric Record》1998,16(92):199-212
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
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
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A. K. Forrest 《The Photogrammetric Record》1990,13(76):511-517
An account is given of the importance of photogrammetric techniques in industrial three dimensional problems and the way in which obtaining data in this environment differs from the more common applications. Possible system arrangements are discussed. The particular choice at Imperial College and the resulting system speed and accuracy are presented. 相似文献
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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
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W. Bösemann 《The Photogrammetric Record》1998,16(92):187-197
Digital photogrammetric systems have been introduced to solve various measurement problems in industrial applications for many years, ever since high resolution CCD cameras and powerful computer technologies have been available. For a successful implementation of a digital photogrammetric system into the production line, not only does the actual measurement task have to be solved but also a complete integration of the system into the production process usually has to be supplied by the system manufacturer. Three examples of successful implementations of photogrammetric systems for industrial automation and process control are presented in this paper. 相似文献
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D. P. Chapman 《The Photogrammetric Record》2000,16(95):763-779
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
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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