• Title/Summary/Keyword: 단사진의 후방교회법

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Comparisons of Single Photo Resection Algorithms for the Determination of Exterior Orientation Parameters (단사진의 외부표정요소 결정을 위한 후방교회법 알고리즘의 비교)

  • Kim, Eui Myoung;Seo, Hong Deok
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.38 no.4
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    • pp.305-315
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    • 2020
  • The purpose of this study is to compare algorithms of single photo resection, which determines the exterior orientation parameters used in fields such as photogrammetry, computer vision, robotics, etc. To this end, the algorithms were compared by generating experimental data by simulating terrain based on a camera used in aerial and close-range photogrammetry. Through experiments on aerial photographic camera that was taken almost vertically, it was possible to determine the exterior orientation parameters using three ground control points, but the Procrustes algorithm was sensitive to the configuration of the ground control points. Even in experiments with a close-range amateur camera where the attitude angles of the camera change significantly, the algorithm was sensitive to the configuration of the ground control points, and the other algorithms required at least six ground control points. Through experiments with two types of cameras, it was found that cosine lawbased spatial resection shows performance similar to that of a traditional photogrammetry algorithm because the number of iterations is short and no explicit initial values are required.

Single Photo Resection Using Cosine Law and Three-dimensional Coordinate Transformation (코사인 법칙과 3차원 좌표 변환을 이용한 단사진의 후방교회법)

  • Hong, Song Pyo;Choi, Han Seung;Kim, Eui Myoung
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.3
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    • pp.189-198
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    • 2019
  • In photogrammetry, single photo resection is a method of determining exterior orientation parameters corresponding to a position and an attitude of a camera at the time of taking a photograph using known interior orientation parameters, ground coordinates, and image coordinates. In this study, we proposed a single photo resection algorithm that determines the exterior orientation parameters of the camera using cosine law and linear equation-based three-dimensional coordinate transformation. The proposed algorithm first calculated the scale between the ground coordinates and the corresponding normalized coordinates using the cosine law. Then, the exterior orientation parameters were determined by applying linear equation-based three-dimensional coordinate transformation using normalized coordinates and ground coordinates considering the calculated scale. The proposed algorithm was not sensitive to the initial values by using the method of dividing the longest distance among the combinations of the ground coordinates and dividing each ground coordinates, although the partial derivative was required for the nonlinear equation. In addition, since the exterior orientation parameters can be determined by using three points, there was a stable advantage in the geometrical arrangement of the control points.

A Study on the Determination of Plane Coordinates Using Single Photo Method (단사진 해석기법을 이용한 평면좌표 결정에 관한 연구)

  • 유복모;박운용;조강연;이용희
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.5 no.2
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    • pp.37-46
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    • 1987
  • The single photo method has a lot of applications in forestry, traffic accident managements, industry, criminal investigation, and in daily life. In this study a new single photo method was developed by classifying into the Space resection method and the 2 Dimensional Perspective Transformation method. Metric and nonmetric cameras were used to analyse the accuracy by means of single photo method, and the errors in coordinates and lengths were studied by changing the number and arrangement of control points to obtain the optimum condition for the single photo method. The influence of number and arrangement of control points on the accuracy was relatively small in case of the Metric WILD P31 and ASAHI PENTAX 6$\times$7 cameras, where as for errors it was a major factor in the Non-metric Nikon FM2. To overcome these defects, at least 6 control points should be used for the errors to be convergent and they should be distributed evenly over the surveying area. It was found that accuracy increased as the object to be photographed was placed in the perpendicular direction to the axis of camera.

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Development of Low-Cost Data Acquisition Method for Close-range Digital Photogrammetric System (근거리 수치사진측량시스템을 위한 저가격 자료획득방법의 개발)

  • Park, Hong-Gi
    • Journal of Korean Society for Geospatial Information Science
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    • v.7 no.2 s.14
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    • pp.143-153
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    • 1999
  • GIS have become easier to use and very popular. In recent year digital photogrammetric systems ire becoming cost-effective tools to build and update GIS databases. In close-range photogrammetry for the acquisition of geospatial data, the bundle adjustment needs both initial approximate values and control points to solve the exterior orientation parameters. This paper gives a review of applied and potential algorithms for estimating Initial approximate values before the bundle adjustment, develope new algorithms for determine the exterior orientation parameters, and gives a cost-effective methods for close-range digital photogrammetric system Modifications of existing DLT algorithm were made in this study for providing an efficient, economic, and more accurate photogrammetric data reduction technique. These modifications include robust approaches for automatic detection and elimination of all lands of gross errors in the measurement data, and incorporation of GPS to reduce the number of control points necessary for a DLT solution. Also, this paper derives a new method for space resection from a monocular image. A major advantage of proposed method is that the solution can be uniquely and analytically determined without initial approximate values of exterior orientation parameters and without iterative computation.

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