• Title/Summary/Keyword: Point-extraction

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A Convex Hull Algorithm for 2D Patterns (2차원 패턴의 볼록 헐 알고리즘)

  • 홍기천;오일석
    • Journal of Korea Multimedia Society
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    • v.4 no.4
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    • pp.363-369
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    • 2001
  • This paper proposes a convex hull algorithm for 2D patterns. The proposed algorithm is divided ito 2steps; candidate convex point extraction and final convex point extraction. First step removes as many points as possible that cannot be convex points using simple operation. Second step computes final convex hull of 2D patterns. This method accelerates execution time, since it consists of simple operations. Experimental results show that the proposed method is faster than other 2 methods in speed.

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P-wave Detection Algorithm by Significant Point Extraction Method (특성점 추출에 의한 P파 검출 알고리즘에 관한 연구)

  • Hwang, Sun-Chul;Jeong, Hee-Kyo;Lee, Myoung-Ho
    • Proceedings of the KIEE Conference
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    • 1989.07a
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    • pp.162-165
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    • 1989
  • This paper describes an algorithm of P-wave detection by significant point extraction method with digital differentiation. P-waves are detected by pattern matching algorithm with significant points. By means of defecting onset and offset points of P-waves, this algorithm can measure the PR intervals exactly which is important to diagnosis the atrial arrhythmia. Because P-wave duration is changed according to heart-rates, we calculate the R-R interval prior to the determination of P-wave duration threshold values in order to actively adapt to the change of P duration The results obtained from the proposed algorithm have defected successfully P-wave almost more than 90%.

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Obstacle Detection for Generating the Motion of Humanoid Robot (휴머노이드 로봇의 움직임 생성을 위한 장애물 인식방법)

  • Park, Chan-Soo;Kim, Doik
    • Journal of Institute of Control, Robotics and Systems
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    • v.18 no.12
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    • pp.1115-1121
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    • 2012
  • This paper proposes a method to extract accurate plane of an object in unstructured environment for a humanoid robot by using a laser scanner. By panning and tilting 2D laser scanner installed on the head of a humanoid robot, 3D depth map of unstructured environment is generated. After generating the 3D depth map around a robot, the proposed plane extraction method is applied to the 3D depth map. By using the hierarchical clustering method, points on the same plane are extracted from the point cloud in the 3D depth map. After segmenting the plane from the point cloud, dimensions of the planes are calculated. The accuracy of the extracted plane is evaluated with experimental results, which show the effectiveness of the proposed method to extract planes around a humanoid robot in unstructured environment.

Feature Point Extraction of Hand Region Using Vision (비젼을 이용한 손 영역 특징 점 추출)

  • Jeong, Hyun-Suk;Joo, Young-Hoon
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.10
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    • pp.2041-2046
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    • 2009
  • In this paper, we propose the feature points extraction method of hand region using vision. To do this, first, we find the HCbCr color model by using HSI and YCbCr color model. Second, we extract the hand region by using the HCbCr color model and the fuzzy color filter. Third, we extract the exact hand region by applying labeling algorithm to extracted hand region. Fourth, after finding the center of gravity of extracted hand region, we obtain the first feature points by using Canny edge, chain code, and DP method. And then, we obtain the feature points of hand region by applying the convex hull method to the extracted first feature points. Finally, we demonstrate the effectiveness and feasibility of the proposed method through some experiments.

Approaches for Automatic GCP Extraction and Localization in Airborne SAR Images and Some Test Results

  • Tsay, Jaan-Rong;Liu, Pang-Wei
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.360-362
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    • 2003
  • This paper presents simple feature-based approaches for full- and/or semi-automatic extraction, selection, and localization (center-determination) of ground control points (GCPs) for radargrammetry using airborne synthetic aperture radar (SAR) images. Test results using airborne NASA/JPL TOPSAR images in Taiwan verify that the registration accuracy is about 0.8${\sim}$1.4 pixels. In c.a. 30 minutes, 1500${\sim}$3000 GCPs are extracted and their point centers in a SAR image of about 512 ${\times}$ 512 pixels are determined on a personal computer.

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Extraction Method of Indoor Stay Point considering the Distribution of GPS Time Data (GPS 데이터 분포를 고려한 실내 Stay Point 추출 방법)

  • Park, Jin-Gwan;Choi, Sang-Gil;Baek, Jong-gil;Jeong, Min-A;Lee, Seong-Ro
    • Proceedings of the Korea Information Processing Society Conference
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    • 2015.10a
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    • pp.1196-1198
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    • 2015
  • 최근 모바일 기기의 발전으로 사용자의 위치를 수집하고 분석하는 방법들이 연구되고 있다. 이러한 방법들 중 하나인 궤적 데이터 마이닝은 사용자의 궤적을 바탕으로 의미 있는 정보를 추출하기 위해 사용된다. 궤적 데이터 마이닝을 수행하기 위해서는 사용자의 GPS로그를 분석하여 Stay Point를 추출하는 과정이 선행되어야 한다. 기존의 Stay Point 추출 방법은 실내와 실외의 Stay Point를 구분하지 못한다. 본 논문에서는 기존의 Stay Point 알고리즘을 보완하기 위해 GPS 데이터 분포를 고려하여 실내에서 머무른 지점만을 추출하는 Stay Point 알고리즘을 제안한다.

A Block Disassembly Technique for Equivalent Circuit Extraction of Mask Layouts (마스크 레이아웃의 등가 회로 추출을 위한 블록 분할 기법)

  • 손영찬;주리아;박석홍;유상대
    • Proceedings of the IEEK Conference
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    • 2000.06b
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    • pp.246-249
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    • 2000
  • In this paper, we describe an automated extraction program that transforms a mask layout into an approximated equivalent circuit information suitable for circuit simulation, and that extract the geometric parameters of stacked MOSFETs and the distributed RCs of layout blocks. To extract equivalent circuit from mask layout, we propose new block disassembly technique capable of accurate computations of distributed RCs at branch point, using vectorized edges which represent the outline of an individual polygon.

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Kidney's feature point extraction based on edge detection using SIFT algorithm in ultrasound image (Edge detection 기반의 SIFT 알고리즘을 이용한 kidney 특징점 검출 방법)

  • Kim, Sung-Jung;Yoo, JaeChern
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2019.07a
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    • pp.89-90
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    • 2019
  • 본 논문에서는 ultrasound image Right Parasagittal Liver에 edge detection을 적용한 후, 특징점 검출 알고리즘인 Scale Invarient Feature Transfom(SIFT)를 이용하여 특징점의 위치를 살펴보도록 한다. edge detection 알고리즘으로는 Canny edge detection과 Prewitt edge detection을 적용하기로 한다.

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Simplification of LIDAR Data for Building Extraction Based on Quad-tree Structure

  • Du, Ruoyu;Lee, Hyo Jong
    • Proceedings of the Korea Information Processing Society Conference
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    • 2011.11a
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    • pp.355-356
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    • 2011
  • LiDAR data is very large, which contains an amount of redundant information. The information not only takes up a lot of storage space but also brings much inconvenience to the LIDAR data transmission and application. Therefore, a simplified method was proposed for LiDAR data based on quad-tree structure in this paper. The boundary contour lines of the buildings are displayed as building extraction. Experimental results show that the method is efficient for point's simplification according to the rule of mapping.

Development of Android Smartphone App for Corner Point Feature Extraction using Remote Sensing Image (위성영상정보 기반 코너 포인트 객체 추출 안드로이드 스마트폰 앱 개발)

  • Kang, Sang-Goo;Lee, Ki-Won
    • Korean Journal of Remote Sensing
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    • v.27 no.1
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    • pp.33-41
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    • 2011
  • In the information communication technology, it is world-widely apparent that trend movement from internet web to smartphone app by users demand and developers environment. So it needs kinds of appropriate technological responses from geo-spatial domain regarding this trend. However, most cases in the smartphone app are the map service and location recognition service, and uses of geo-spatial contents are somewhat on the limited level or on the prototype developing stage. In this study, app for extraction of corner point features using geo-spatial imagery and their linkage to database system are developed. Corner extraction is based on Harris algorithm, and all processing modules in database server, application server, and client interface composing app are designed and implemented based on open source. Extracted corner points are applied LOD(Level of Details) process to optimize on display panel. Additional useful function is provided that geo-spatial imagery can be superimposed with the digital map in the same area. It is expected that this app can be utilized to automatic establishment of POI (Point of Interests) or point-based land change detection purposes.