• 한국공간정보시스템학회:학술대회논문집
• /
• 2005.11a
• /
• pp.29-34
• /
• 2005

Aerial photogrammetry, which is one of the most frequent used technology in mapping and surveying, has been appreciated for its work flow and accuracy to generate 2D and 3D geospatial data. In aerial photograrnrnetry, more than two photographs are taken over the same target area in different position with overlap. Using these photographs and minimum number of ground control points, 3D stereo model is so formed that the ground surface in reality is reconstructed through analogue/analytical plotter or digital photogrammetry system. In case of digital photogrammetry system, 3D geospatial data could be automatically extracted in partial. Recently, in the advent of aerial digital camera such as ADS40 and DMC, digital photogrammetry system will be in the frist place for generating 3D geospatial data. In this paper, we experimentally generated 3D geospatial data using digital photograrnrnetry system in the aspect of work flow.

• Spatial Information Research
• /
• v.10 no.2
• /
• pp.317-329
• /
• 2002

Coastal landforms such as sand beach and coastal sand dune are changing dynamically, and the research about them is being conducted. Conventionally the leveling method has been applied to measuring heights of dynamic morphological surface in coastal landforms. We applied the photograrmmetric method which was not considered to measure the heights on coastal sand dune’s profile to calculating the heights of coastal sand dune; that is, the heights of unknown points on coastal sand dune’s profile was reckoned from the digital photographs’stereo pairs through bundle adjustment and backward transform of collinearity condition equation. we used six GCPs to perform bundle adjustment. After backward transform the error of heights between surveyed value and computed value was estimated around 10cm. In general, the pole is not adamantly fixed on the surface of coastal sand dune because of its softness, and then the disturbance of coastal sand dune adjoining surveyed area can be made in small area. Digital photogrammetry can solve the problem which conventional leveling method has, and be replaced it.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2006.04a
• /
• pp.277-280
• /
• 2006

항공사진이나 인공위성 영상을 이용하여 DEM을 생성하는 연구는 전통적으로 사진측량학 분야에서 이루어져 왔다. 즉, 항공기 및 위성을 이용하여 획득한 입체의 영상자료를 이용하여 DEM을 생성하는 기법은 전통적으로 행해져 왔고 최근에 들어서는 LIDAR를 이용하여 1m 급 이상의 정밀 DEM이 획득되고 있다. 그러나 자국 이외 지역에 대한 DEM 자료를 획득하는 일은 위성 및 항공기를 이용한 입체쌍의 영상자료, 기준점 등의 자료를 얻기가 힘들기 때문에 공간해상도가 90m인 USGS에서 제공하는 SRTM자료를 활용해야 하는 등 제한적이다. 이에, 본 연구에서는 공간해상도 15m의 DEM 생성이 가능한 ASTER 영상을 이용하여 중국지역에 대한 정밀 DEM을 생성하고자 하였다. ASTER 영상은 가시광선대, 적외선대 및 열밴드의 정보를 제공하고 있을 뿐만 아니라 DEM 제작을 위하여 위성진행 경로에 정방향 및 역방향의 입체 영상을 제공하고 있다. 이러한 ASTER 영상의 센서 정보와 접합점을 이용하여 DEM을 생성하였고, 이를 SRTM 자료와 동기화 하여 두 자료를 비교 분석하였다.

• Tunnel and Underground Space
• /
• v.26 no.5
• /
• pp.348-362
• /
• 2016

This study describes the results of blasting overbreak analysis using the stereo photogrammetry method in an underground mine. For comparing its quantitative measurements, LIDAR system was applied to the test site and blasting overbreak was analyzed for 4 test blasting operations. The difference in values obtained from the two methods showed only 0.81% in volume and 1.05% in area, respectively, therefore authors verify the field applicability of stereo photogrammetry method on underground mine. The volumes of overbreak measured from 4 test blastings were $29.84m^3$, $22.45m^3$, $14.54m^3$ and $5.46m^3$, respectively, in photogrammetry analysis on excavation surface, and it was shown that the volume of overbreak decreases with blasting sequence. From these measurements, it is concluded that the stereo photogrammetry method can describe the underground excavation surface effectively and the its quantitative data can be used for analysis of volume, area and overbreak of excavation zone.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2007.04a
• /
• pp.197-200
• /
• 2007

항공사진 원데이터의 변형을 방지하고 효율적인 관리를 위해서는 자동독취를 통한 수치화 방안이 마련되어야 한다. 항공사진 판독업무에 있어서 기존 판독자만 밀착항공사진과 입체경을 통하여 건축물의 형태와 변화 여부를 판단하던 것을 모니터 상에서 누구나 건물의 변동사항을 볼 수 있도록 효율적인 판독시스템을 구축하여 판독의 신뢰도를 높여야 한다. 판독시스템 구축은 디지털 영상의 다양한 활용과 업무의 효율성 확보 및 대민서비스 향상 차원에서 이루어져야 할 것이다. 또한 현재 외국의 항측사들이 실제로 활용하고 있으며 조만간 국내에서도 도입 예정인 디지털항공카메라는 항공사진의 수치화 단계를 거치치 않고 직접 수치항공영상을 취득 할 수 있으므로 수치화 과정에서 발생하는 많은 오류들을 제거할 수 있음은 물론 판독시스템을 활용한 데이터의 직접처리가 가능해 시간적, 경제적으로 많은 장점들을 가지고 있다. 그러므로 디지털항공카메라의 도입에 대비한 개발현황과 활용도 등에 관한 사전 연구가 수행되어야 한다. 본 연구에서는 사용자가 직접 입체 판독 및 분석을 수행할 수 있는 플랫폼을 구비함으로서 오류를 최소화 할 수 있도록 편광 모니터(Z-Screen)를 사용하여 수행하였다. 또한 환경은 Microsoft Window OS 환경 상에서 구동될 수 있도록 개발함으로서 시스템의 범용적 사용을 위한 기초 환경을 제공하도록 제안하였다.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2004.11a
• /
• pp.153-159
• /
• 2004

Recently remote sensing technology is applied for digital and photographical data acquisition by use of satellites sensors. And It used for images restoration of vanished spatial information at the same sites according to changed of time and spaces. In this study, it applied for the 3-dimensional images generation and fly simulation to possibility for various application. As a results of its applied, it gained the results not only improvement of present methods but also real various application possibilities for 3 dimensional Image restoration.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.16 no.2
• /
• pp.203-211
• /
• 1998

A traditional method to produce three dimensional orthophoto map has been studied by digital photogrammetry which decides a height by digitally searching conjugate points on the stereo image. Many researches in digital photogrammetric field are still in progress to determine conjugate points automatically. In this study, we analyze the effect of accuracy of area-based image matching with changing eight types of target area size using four types of image pyramid. The result of image matching to each method compared with 1/5,000 digital mapping data. We decided a optimal size of target area on a percentage of image matching. Digital elevation model is generated by matching results and bundle method. As a result, three dimensional orthophoto map is made in terms of digital elevation model and orthophoto.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.10 no.2
• /
• pp.25-30
• /
• 1992

Most algorithms in computer vision and digital photogrammetry assume that digital stereo pairs are registered in epipolar geometry. But, an aerial stereo pair is not likely to be in epiplar geometry since the attitude of the camera at the instant of exposure is different at every exposure station. In this paper, stereo digital imagery is obtained from aerial stereo pair by scanner. Then procesure to resample the digital imagery to epipolar geometry using exterior orientation elements after absolute orientation is described. As a result, a stereo imagery in epipolar geometry is produced from stereo digital imagery. Epipolar imagery in this paper is applied to the image matching method by digital image correlation technique. Then, a digital elevation model is produced from the result of image matching. The digital elevation model in this paper is compared to the other digital elevation model produced by analytical plotter. As a result, an economical method to generate digital elevation model is presented.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.19 no.1
• /
• pp.77-83
• /
• 2001

To product the map by terrestrial photogrammetry method, a few rather nuisance stereo image acquiring processing and plot using expensive analytical instruments have to be performed. In this study, plot was made by acquiring and rectification image using simple method rather than above it. For this, geometry rectification system was constructed for the generation of single ortho-image analysis. and these ortho-images of architecture were made and analysed by appling various warping methods. As a result, the performance of single image analysis could be estimated, and it is expected that the application of this is possible to various non-topographic photogrammetry.

• Tunnel and Underground Space
• /
• v.17 no.2 s.67
• /
• pp.139-151
• /
• 2007

Stereophotogrammetry is a method to extract information of an interested area by constructing a stereo-image from two or more photos. In this study, the stereophotogrammetry was adopted to obtain the joint orientation and trace length from a sampling window and its measurements were compared with the result by a clinocompass and measuring tape to evaluate the applicability of the stereophotogrammetry to rock joint survey. A commercial stereophotogrammetry program, ShapeMetriX 3D, was used for this purpose. Firstly, the accuracy of the measuring method using ShpaeMetrix 3D was evaluated by a model test. Secondly, joint orientations on a rock slope and tunnel were obtained by using ShapeMetriX 3D and compared with the measurement by a clinocompass. Finally. the effect of base-depth ratio in photographing was evaluated by comparing images with various base-depth ratios, and the usefulness of closed-up photographing on a rock exposure to increase the measurement accuracy was tested. The dip and dip direction of each model plane obtained by ShapeMetriX 3D showed an error ranged between $-5^{\circ}\;and\; 5^{\circ}$ on the basis of the results by the measuring tape. Base-depth ratio proved not to influence the analysis result by ShapeMetriX 3D if all the images were taken without any hidden area. The close-up photographing turned out useful to obtain the detailed images and therefore precise result when ShapeMetriX 3D was adopted.