• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.1
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• pp.1-7
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• 2003

Practical use is increasing on the aerial ortho image recently, and much researches for geographic information system build that use high resolution satellite image cause this are progressing. Also many researches that use KOMPSAT-1 satellite image of resolution 6.6m are performing in these days, estimation for between aerial photo and satellite image is needed. In this treatise scanned image of aerial photo, using aerial photo resampling image of resolution equal with KOMPSAT-1 image using aerial photo, and KOMPSAT-1 satellite image use for experimental image making each orthoimage, classified feature for estimate. We evaluated to what level that an separation item could be able to estimate in each orthoimage. As result of estimation analysis, In the classified feature in aerial photo orthoimage with aerial photo resampling image orthoimage is about 61%, KOMPSAT-1 satellite image orthoimage is almost 41% could estimated. Through this investigation estimate, KOMPSAT-1 satellite sue to map updating, geographic information og non-approach area and environment inspect.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2010.04a
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• pp.225-226
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• 2010

The problem in orthoimage generation is to recover occlusion areas. In this study, occlusion areas - double mapping regions of the building roofs - were mutually corrected by using multiple images. The proposed method could be efficient for generating true orthoimages in urban areas.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.1
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• pp.83-92
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• 2010

Emergence of high-resolution digital aerial cameras and airborne laser scanners have made innovative progress in photogrammetry and spatial information technology. The purpose of this study is to generate true orthoimage by recovering occlusion areas. The orthoimages were generated patch-based transformation. The occlusion areas were mutually corrected by using multiple aerial images. This study proposed a novel method of building roof based orthoimage generation and an effective method of occlusion area detection and recovery. The proposed methods could be efficient to generate true orthoimages in urban areas where occlusion areas are problematic.

• Journal of the Society of Disaster Information
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• v.15 no.3
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• pp.427-439
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• 2019

Purpose: We generated geospatial information of unmanned aerial vehicle based on various SW and analyzed the location accuracy of orthoimage and DSM and texture mapping of 3D mesh. Method: The same unmanned aerial image data is processed using two different SW, and spatial information is generated. Among the generated spatial information, the orthoimage and DSM were compared with the spatial information generation results of the unmanned aerial photogrammetry SW by performing quantitative analysis by calculating RMSE of horizontal position and vertical position error and performing qualitative analysis. Results: There were no significant differences in the positional accuracy of the orthoimage and DSM generated by each SW, and differences in texture mapping in 3D mesh. The creation of the 3D mesh indicated the impact of the Unmanned Aerial Photogrammetry SW. Conclusion: It is shown that there is no effect of SW on the creation of orthoimage and DSM for geospatial analysis based on unmanned aerial vehicle. However, when 3D visualization is performed, texture mapping results are different depending on SW.

• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.1
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• pp.84-93
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• 2011

Levee line mapping is critical to the protection of environments in river zones, the prevention of river flood and the development of river zones. Use of the remote sensing data such as LiDAR and aerial orthoimage is efficient for river mapping due to their accessibility and higher accuracy in horizontal and vertical direction. Airborne laser scanning (LiDAR) has been used for river zone mapping due to its ability to penetrate shallow water and its high vertical accuracy. Use of image source is also efficient for extraction of features by analysis of its image source. Therefore, aerial orthoimage also have been used for river zone mapping tasks due to its image source and its higher accuracy in horizontal direction. Due to these advantages, in this paper, research on three dimensional levee line mapping is implemented using LiDAR and aerial orthoimage separately. Accuracy measurement is implemented for both extracted lines generated by each data using the ground truths and statistical comparison is implemented between two measurement results. Statistical results show that the generated 3D levee line using LiDAR data has higher accuracy than the generated 3D levee line using aerial orthoimage in horizontal direction and vertical direction.

• Journal of Korean Society for Geospatial Information Science
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• v.24 no.3
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• pp.3-9
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• 2016

UAV(unmanned aerial vehicle) can quickly produce orthoimage with high-spatial resolution and DSM(digital surface model) at low cost. However, vertical and horizontal positioning accuracy of orthoimage and DSM, which are obtained by UAV, are influenced by image processing techniques, quality of aerial photo, the number and position of GCPs(ground control points) and overlap in flight plan. In this study, effects of overlap and the number of GCPs are analyzed in orthoimage and DSM. Positioning accuracy are estimated based on RMSE(root mean square error) by using dataset of nine pairs. In the experiments, Overlaps and the number of GCPs have influence on horizontal and vertical accuracy of orthoimage and DSM.

• Journal of Korean Society for Geospatial Information Science
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• v.15 no.4
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• pp.31-39
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• 2007

As the availability of images from airborne digital camera with high resolution is expanded, a lot of concern are shown about the production of orthoimage and digital map. This study presents the method of updating digital map using orthoimage from airborne digital camera image. Images were georectified using GPS surveying data. For the generation of orthoimage, Lidar DEM was used. The absolute positional accuracy of orthoimage was evaluated using GPS surveying data. And that of the building layer of digital map was estimated using the existed digital map at the scale of 1:1,000. The absolute positional accuracy of orthoimage was as followed: RMSE in X and Y were ${\pm}0.076m$ and ${\pm}0.294m$. The RMSE of the building layer were ${\pm}0.250m$ and ${\pm}0.210m$ in X and Y directions, respectively. The RMSE of the digital map using orthoimage from Aerial Digital Camera image fell within allowable error range established by NGII. Consequently, updating digital map using orthoimage from Aerial Digital Camera image can be applied to various fields including the construction of the framework data and the GIS of local government.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.181-184
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• 2008

The quality of orthoimages mainly depends on the elevation information and exterior orientation (EO) parameters. Since LiDAR data directly provides the elevation information over the earth's surface including buildings and trees, the concept of true orthorectification has been rapidly developed and implemented. If a LiDAR-driven digital surface model (DSM) is used for orthorectification, the displacements caused by trees and buildings are effectively removed when compared with the conventional orthoimages processed with a digital elevation model (DEM). This study sequentially utilized LiDAR data to generate orthorectified digital aerial images. Experimental orthoimages were produced using DTM and DSM. For the preparation of orthorectification, EO components, one of the inputs for orthorectification, were adjusted with the ground control points (GCPs) collected from the LiDAR point data, and the ground points were extracted by a filtering method. The orthoimage generated by DSM corresponded more closely to non-ground LiDAR points than the orthoimage produced by DTM.

• Korean Journal of Remote Sensing
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• v.24 no.5
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• pp.463-471
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• 2008

The quality of orthoimages mainly depends on the elevation information and exterior orientation (EO) parameters. Since LiDAR data directly provides the elevation information over the earth's surface including buildings and trees, the concept of true orthorectification has been rapidly developed and implemented. If a LiDAR-driven digital surface model (DSM) is used for orthorectification, the displacements caused by trees and buildings are effectively removed when compared with the conventional orthoimages processed with a digital elevation model (DEM). This study utilized LiDAR data to generate orthorectified digital aerial images. Experimental orthoimages were produced using digital terrain model (DTM) and DSM. For the preparation of orthorectification, EO components, one of the inputs for orthorectification, were adjusted with the ground control points (GCPs) collected from the LiDAR point data, and the ground points were extracted by a filtering method used in a previous research. The orthoimage generated by DSM corresponded more closely to non-ground LiDAR points than the orthoimage produced by DTM.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.295-301
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• 2004

Satellite captures images periodically and economically over the area wider than aerial photographs, and reconnaissance to unapproachable area. For these advantages, mapping using high resolution satellite image has high potentials of marketability and development. Therefore, utilization of satellite image in mapping and GIS is expected to be growing and research on describable feature, positional accuracy and, possible mapping scale is urgently needed. This research presented that Quick Bird orthoimage could be used to update digital map on a scale of 1:5,000. Quick Bird image was corrected geometrically based on ground control points. DEM was generated using height data of digital topographic map. The orthoimge was produced by digital differential rectification based on DEM which was generated using height data of digital topographic map(scale 1;5,000 and 1;1,000). When the digital topographic map was overlaid with the orthoimage, it was very easy to find changed region or new features builded after the map compiled.