• Title/Summary/Keyword: Topographical Images

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A SHAPE FEATURE EXTRACTION FOR COMPLEX TOPOGRAPHICAL IMAGES

  • Kwon Yong-Il;Park Ho-Hyun;Lee Seok-Lyong;Chung Chin-Wan
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.575-578
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    • 2005
  • Topographical images, in case of aerial or satellite images, are usually similar in colors and textures, and complex in shapes. Thus we have to use shape features of images for efficiently retrieving a query image from topographical image databases. In this paper, we propose a shape feature extraction method which is suitable for topographical images. This method, which improves the existing projection in the Cartesian coordinates, performs the projection operation in the polar coordinates. This method extracts three attributes, namely the number of region pixels, the boundary pixel length of the region from the centroid, the number of alternations between region and background, along each angular direction of the polar coordinates. It extracts the features of complex shape objects which may have holes and disconnected regions. An advantage of our method is that it is invariant to rotation/scale/translation of images. Finally we show the advantages of our method through experiments by comparing it with CSS which is one of the most successful methods in the area of shape feature extraction

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A Shape Feature Extraction Method for Topographical Image Databases (지형/지물 이미지 데이타베이스를 위한 형태 특징 추출 방법)

  • Kwon Yong-Il;Park Ho-Hyun;Lee Seok-Lyong;Chung Chin-Wan
    • Journal of KIISE:Databases
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    • v.33 no.4
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    • pp.384-395
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    • 2006
  • Topographical images such as aerial and satellite images are usually similar with respect to colors and textures but not in shapes. Thus shape features of the images and the methods of extracting them become critical for effective image retrieval from topographical image databases. In this paper, we propose a shape feature extraction method for topographical image retrieval. The method extracts a set of attributes which can model the presence of holes and disconnected regions in images and is tolerant to pre-processing, more specifically segmentation, errors. Various experiments suggest that retrieval using attributes extracted using the proposed method performs better than using existing shape feature extraction methods.

Application Study on the View Points Analysis for National Roads Route using Digital Elevation Data

  • Yeon, Sang-Ho;Hong, Ill-Hwa
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.292-296
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    • 2002
  • This study has been accomplished as a experimental study for field application of 3D Perspective Image Map creation using Digital Topographical Map and based on the Ortho-Projection Image which is generated from Satellite Overlay Images and the precise Relative Coordinates of longitude, latitude and altitude which is corrected by GCP(Ground Control Point). AS to Contour Lines Map which is created by Coordinate conversion of 1:5,000 Topographical Map, we firstly made Satellite Image Map to substitute for Digital Topographical Map through overlapping the original images on top of each Ortho-Projection Image created and checking the accuracy. In addition to 3D Image Map creation for 3D Terrain analysis of a target district, Slope Gradient Analysis, Aspect Analysis and Terrain Elevation Model generation, multidirectional 3D Image generation by DEM can be carried out through this study. This study is to develop a mapping technology with which we can generate 3D Satellite Images of a target district through the composition of Digital Maps and Facility Blueprint and arbitrarily create 3D Perspective Images of the target district from any view point.

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Analysis of Quantitative Topographical Change in Eulsuk-Island Using Aerial Images (항공영상을 이용한 을숙도 지형의 정량적 변화 분석)

  • Lee, Jae-One;Song, Yu-Jin;Kim, Yong-Suk;Park, Hong-Joo
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.29 no.5
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    • pp.527-534
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    • 2011
  • This paper describes an analysis of topographical changes to the Eulsuk-Island at the Nakdong River Estuary using a long-term dataset of high resolution aerial images from 1983 to 2007. Ground control surveying was performed at some feature points using GPS(Global Positioning System) to accomplish AT(Aerial Triangulation) for past aerial images. Even if some still existing feature points appeared on old aerial images were used as GCPs(Ground Control Points) for past aerial images in AT, its accuracy reached at 1m level. Since then, a quantitative analysis of topographical changes was conducted on digital orthophotos produced by a series of aerial images taken by different years. The change volume of total area, construction, vegetation, buildings and roads could be extracted per each period in study area. The total area decreased from 1983 to 1992, but it has not almost changed since 1992. According to the continuous development, the area of vegetation has steadily decreased, while that of buildings and roads has generally increased. The result of this study can provide us with invaluable base data for further topographical change monitoring in Eulsuk-Island and Nakdong River estuary caused by continuous development in this area.

Application of EOC Images to Developed the GIUH (지형학적순간단위유랑도 분석을 위한 EOC 스테레오 영상 활용)

  • Choi, Hyun;Kang, In-Joon;Hong, Sun-Heun
    • Korean Journal of Remote Sensing
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    • v.20 no.2
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    • pp.91-102
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    • 2004
  • This paper reflects the estimation of using the EOC(Electro-optical Camera) images supporting GIUH(geomorphological instantaneous unit hydrograph) approach. We have analyzed GIUH in its density and frequency distribution by creating a DEM(digital elevation model) for the sub basin produced from the EOC images and examined topographical and hydrological application possibility of the EOC images. In this process, we have topographical basin characteristic analysis that use the remote sensing technique analyzing the DEM creation process of the EOC stereo images by studying the basic topographical hydrology analysis about abstraction technique since it is flirty complex and is more time-consuming than other method. we executed statistical analysis of a basin size and river length using the frequency function after divided lattice spacing applied have to the sub river basin from the image data and the digital map into 10m intervals ranging from 10m to 100m. After comparing and examining the peak and time to peak of the GIUH, we proceeded with a comparative analysis by lattice concerning the topographical divergence rate, area ratio, length ratio. Accumulating the peak and time to peak of the GIUH is altered to non-linear form in accordance to lattice dimension as well as basin factor. It was proved that the lattice dimension is one of the important factors about the peak and time to peak of the GIUH.

Developing a Cantilever-type Near-field Scanning Optical Microscope Using a Single Laser for Topography Detection and Sample Excitation

  • Ng'ang'a, Douglas Kagoiya;Ali, Luqman;Lee, Yong Joong;Byeon, Clare Chisu
    • Current Optics and Photonics
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    • v.5 no.3
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    • pp.229-237
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    • 2021
  • The capabilities of the near-field scanning optical microscope (NSOM) for obtaining high resolution lateral topographical images as well as for mapping the spectroscopic and optical properties of a sample below the diffraction limit of light have made it an attractive research field for most researchers dealing with optical characteristics of materials in nano scales. The apertured NSOM technique involves confining light into an aperture of sub-wavelength size and using it to illuminate a sample maintained at a distance equal to a fraction of the sub-wavelength aperture (near-field region). In this article, we present a setup for developing NSOM using a cantilever with a sub-wavelength aperture at the tip. A single laser is used for both cantilever deflection measurement and near-field sample excitation. The laser beam is focused at the apex of the cantilever where a portion of the beam is reflected and the other portion goes through the aperture and causes local near-field optical excitation of the sample, which is then raster scanned in the near-field region. The reflected beam is used for an optical beam deflection technique that yields topographical images by controlling the probe-sample in nano-distance. The fluorescence emissions signal is detected in far-field by the help of a silicon avalanche photodiode. The images obtained using this method show a good correlation between the topographical image and the mapping of the fluorescence emissions.

Experimental Study on Satellite Image Restoration for Vanished Area by Dam Construction

  • Yeon, Sang-Ho;Hong, Il-Hwa
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1424-1426
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    • 2003
  • It will be a real good news for the people who were lost their hometown by the construction of a large dam to be restored to the former state. Focused on Cheung-Pyung around where most part were flooded by the Chungju large Dam founded in early 1980s, we used Remote Sensing Technique in this study in order to restore topographical features before the flood with 3 dimensional effects. We gathered comparatively good satellite photos and remotely sensed digital images, then we made a new color image from these and the topographical map which had been made before the flood. This task was putting together two kinds of different timed images. And then, we generated DEM including the outskirts of that area as harmonizing current contour lines with the map. That could be a perfect 3D image of Cheung-Pyung around before when it had been flood by making perspective images from all directions, north, south, east and west, for showing there in three dimensions. Also, flying simulation we made for close visiting can bring us to experience their real space at that time.

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DNA Band Recognition using the Topographical Features of Images (영상의 지형적 특징에 의한 유전밴드 인식)

  • Hwang, Deok-In;Gong, Seong-Gon;Jo, Seong-Won;Jo, Dong-Seop;Lee, Seung-Hwan
    • Journal of KIISE:Software and Applications
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    • v.26 no.11
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    • pp.1350-1358
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    • 1999
  • 이 논문에서는 유전밴드 영상신호에 포함되어 있는 지형적 특징을 이용하여 밝기의 변화가 일정하지 않은 유전밴드를 인식하는 방법을 연구하였다. 유전밴드는 동일인을 식별하는데 있어서 지문보다 높은 신뢰성을 가지고 있으므로, 유전밴드 영상에서 유전밴드의 유무와 위치를 자동적으로 검출하는 것은 매우 중요하다. 레인내의 밝기의 변화가 일정한 유전밴드는 미분연산자에 의해 검출할 수 있지만, 밝기의 변화가 일정하지 않은 레인내의 유전밴드는 일반적인 인식방법에 의해서는 검출하기 어렵다. 따라서 유전밴드 영상으로부터 지형적 특징을 추출하고, 이것으로부터 계산한 곡률(curvature)의 크기에 의해 유전밴드를 인식함으로써 레인의 밝기가 변화하는 경우에도 효과적으로 인식하였다.Abstract This paper presents recognition of DNA band using the topographical features of DNA band images. The DNA band provides a more reliable way of identification than fingerprints. Recognition based on differentiation operators can easily detect the DNA band if the brightness of lane in the image is almost uniform. When the brightness of the lane changes gradually, the DNA bands are hard to be recognized. Using the curvature magnitude of the lane computed from topographic features extracted from DNA images, the DNA bands are efficiently recognized in the lane whose brightness changes.

A Topographical Classifier Development Support System Cooperating with Data Mining Tool WEKA from Airborne LiDAR Data (항공 라이다 데이터로부터 데이터마이닝 도구 WEKA를 이용한 지형 분류기 제작 지원 시스템)

  • Lee, Sung-Gyu;Lee, Ho-Jun;Sung, Chul-Woong;Park, Chang-Hoo;Cho, Woo-Sug;Kim, Yoo-Sung
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.28 no.1
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    • pp.133-142
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    • 2010
  • To monitor composition and change of the national land, intelligent topographical classifier which enables accurate classification of land-cover types from airborne LiDAR data is highly required. We developed a topographical classifier development support system cooperating with da1a mining tool WEKA to help users to construct accurate topographical classification systems. The topographical classifier development support system has the following functions; superposing LiDAR data upon corresponding aerial images, dividing LiDAR data into tiles for efficient processing, 3D visualization of partial LiDAR data, feature from tiles, automatic WEKA input generation, and automatic C++ program generation from the classification rule set. In addition, with dam mining tool WEKA, we can choose highly distinguishable features by attribute selection function and choose the best classification model as the result topographical classifier. Therefore, users can easily develop intelligent topographical classifier which is well fitted to the developing objectives by using the topographical classifier development support system.