• Title/Summary/Keyword: edge & line method

Search Result 355, Processing Time 0.021 seconds

Needle Detection by using Morphological Operation and Line Segment Approximation (형태학적 연산과 선분 근사화를 이용한 침 검출)

  • Jang, Kyung-shik;Han, Soowhan
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.19 no.12
    • /
    • pp.2785-2791
    • /
    • 2015
  • In this paper, neddle detection algorithm for the removal of needle stuck into skin in oriental clinic is presented. First, in the proposed method, potential candidate areas of each needle are selected by using the morphological open operation in a gray image, and the false candidates are removed by considering their area size. Next, edge points are extracted using canny edge detector in selected candidate areas, line segments are approximated using the edge points. Based on the direction of line segment and the distance between two line segments, two main line segments of the needle are extracted. The final verification of needle is accomplished by using the morphological analysis of these two line segments. In the experiments, the detection rate of proposed method reaches to 97.5% for the 16 images containing 119 needles.

Line Edge-Based Type-Specific Corner Points Extraction for the Analysis of Table Form Document Structure (표 서식 문서의 구조 분석을 위한 선분 에지 기반의 유형별 꼭짓점 검출)

  • Jung, Jae-young
    • Journal of Digital Contents Society
    • /
    • v.15 no.2
    • /
    • pp.209-217
    • /
    • 2014
  • It is very important to classify a lot of table-form documents into the same type of classes or to extract information filled in the template automatically. For these, it is necessary to accurately analyze table-form structure. This paper proposes an algorithm to extract corner points based on line edge segments and to classify the type of junction from table-form images. The algorithm preprocesses image through binarization, skew correction, deletion of isolated small area of black color because that they are probably generated by noises.. And then, it processes detections of edge block, line edges from a edge block, corner points. The extracted corner points are classified as 9 types of junction based on the combination of horizontal/vertical line edge segments in a block. The proposed method is applied to the several unconstraint document images such as tax form, transaction receipt, ordinary document containing tables, etc. The experimental results show that the performance of point detection is over 99%. Considering that almost corner points make a correspondence pair in the table, the information of type of corner and width of line may be useful to analyse the structure of table-form document.

Theory and Experiment of the Cylindrical Edge-Slot Antenna with Coaxial Line Feed (동축선로로 급전된 원통형 에지-슬롯 안테나의 이론 및 실험)

  • 유상기;홍재표;조영기
    • Journal of the Korean Institute of Telematics and Electronics A
    • /
    • v.31A no.2
    • /
    • pp.39-44
    • /
    • 1994
  • A theoretical method has been considered for the analysis of a cylindrical edge-slot antenna which belongs to a class of circumferential slot antennas that are suitable for conformal mounting on conducting bodies of revolution. A coupled integral equation is formulated for unknown magnetic currents of both the coaxial aperture and the edge slot, and solved by the moment method. Theoretical values for reflection coefficient obtained based upon the method are compared with our experimental values and other author's results available. There arre good agreement between them.

  • PDF

A New line Matching Technique for Solving Correspondence Problem in Stereo Method (스테레오 방식에서 일치성 문제를 해결하기 위한 새로운 선소 정합법)

  • Kang, Dae-Kap;Kwon, Jung-Jang;Kim, Seong-Dae
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.27 no.3
    • /
    • pp.116-123
    • /
    • 1990
  • Most algorithms utilized the horizontal epipolar lines for solving the correspondence problem in 3-D computer vision. However, the requirement is very difficult to be satisfied in real situations. In this paper, we propose a binocular-stereo matching algorithm, based on line matching method, which does not require the horizontal epipolar lines of the extreme pixels of a given line segment and two circles whose radius is equal to the maximum disparity. And we use the features including the direction of line segments, edge strength and cross-correlation for line matching. The experimental results show that the proposed algorithm can be a useful tool for solving the correspondence problem in 3-D computer vision.

  • PDF

Trimming Line Design using Incremental Development Method and Finite Element Inverse Method (점진 전개기법 및 유한요소 역해석법을 이용한 자동차 패널 트리밍 라인 설계)

  • Chung, W.J.;Park, C.D.;Song, Y.J.;Oh, S.W.
    • Transactions of Materials Processing
    • /
    • v.15 no.6 s.87
    • /
    • pp.445-452
    • /
    • 2006
  • In most of automobile body panel manufacturing, trimming process is generally performed before flanging. To find feasible trimming line is crucial in obtaining accurate edge profile after flanging. Section-based method develops blank along manually chosen section planes and find trimming line by generating loop of end points. This method suffers from inaccurate results of edge profile. On the other hand, simulation-based method can produce more accurate trimming line by iterative strategy. In this study, new fast simulation-based method to find feasible trimming line is proposed. Finite element inverse method is used to analyze the flanging process because final shape after flanging can be explicitly defined and most of strain paths are simple in flanging. In utilizing finite element inverse method, the main obstacle is the initial guess generation for general mesh. Robust initial guess generation method is developed to handle genera] mesh with very different size and undercut. The new method develops final triangular mesh incrementally onto the drawing tool surface. Also in order to remedy mesh distortion during development, energy minimization technique is utilized. Trimming line is extracted from the outer boundary after finite element inverse method simulation. This method has many advantages since trimming line can be obtained in the early design stage. The developed method is verified by shrink/stretch flange forming and successfully applied to the complex industrial applications such as door outer flanging process.

A New Design Method of Tapped Coupled-Line Filters (탭 선로를 이용한 새로운 결합선로 여파기 설계법)

  • 우동식;김강욱
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.15 no.11
    • /
    • pp.1100-1107
    • /
    • 2004
  • In this paper, a new design method fur tapped coupled-line filters has been developed. The design equations for this tapped-line filter have been obtained using a new equivalent circuit model of tapped lines. These tapped-lines replace input/output coupled lines of the conventional edge coupled-line filters, which tend to have very narrow line gaps(few mils). Therefore, tapped coupled-line filters tend to be less sensitive to filter fabrication tolerances and to be easily fabricated using milling tools. The new filter design algorithm allows very accurate filter design for frequencies up to 20 GHz and bandwidth less than 20 %.

A Study on the Edge Construction of CMM Data Using a Method of Mean Curvature Block (평균곡률 구간법을 이용한 CMM 데이터의 경계 형성 연구)

  • Chang, Byoung-Chun;Kim, Dae-Il;Oh, Seok-Hyung
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.9 no.1
    • /
    • pp.74-80
    • /
    • 2010
  • The purpose of reverse engineering design using 3D measurement data is an accurate reconstruction of real body. In oder to accomplish this object, it is important that creating exact extracting edges should be studying out first of all. This study used edge-based method to find out edge point from the measuring point data. The characteristics are analysed using the mean curvature block method on the fitting NURBS curve and defined edges through block removal condition. The results showed that only using the NURBS curve of maximum curvature analysis to define correct edge of real geometry is limited, but this segmentation approach provides simplified necessary condition for edge classification, and an effectiveness to classify a straight line, curves and fillets etc.

Correction of Signboard Distortion by Vertical Stroke Estimation

  • Lim, Jun Sik;Na, In Seop;Kim, Soo Hyung
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.7 no.9
    • /
    • pp.2312-2325
    • /
    • 2013
  • In this paper, we propose a preprocessing method that it is to correct the distortion of text area in Korean signboard images as a preprocessing step to improve character recognition. Distorted perspective in recognizing of Korean signboard text may cause of the low recognition rate. The proposed method consists of four main steps and eight sub-steps: main step consists of potential vertical components detection, vertical components detection, text-boundary estimation and distortion correction. First, potential vertical line components detection consists of four steps, including edge detection for each connected component, pixel distance normalization in the edge, dominant-point detection in the edge and removal of horizontal components. Second, vertical line components detection is composed of removal of diagonal components and extraction of vertical line components. Third, the outline estimation step is composed of the left and right boundary line detection. Finally, distortion of the text image is corrected by bilinear transformation based on the estimated outline. We compared the changes in recognition rates of OCR before and after applying the proposed algorithm. The recognition rate of the distortion corrected signboard images is 29.63% and 21.9% higher at the character and the text unit than those of the original images.

Numerical Analysis of Misaligned Finite Line Contacts EHL Problem (Misalignment가 있는 유한한 선접촉 EHL 문제의 수치해석)

  • Park, Tae-Jo
    • Tribology and Lubricants
    • /
    • v.26 no.5
    • /
    • pp.263-271
    • /
    • 2010
  • The rollers of cylindrical roller bearing are axially profiled to relieve high edge stress concentration caused by mainly their finite length and by misalignment. In this paper, a numerical analysis is carried to study the EHL of misaligned (tilted) rollers with axially profiled ends. Using a finite difference method with non-uniform grids and the Newton-Raphson method, the highly nonlinear EHL problems are systematically solved. Physically consistent solutions are obtained for moderate load, material parameters and very small misalignment. For different misalignment angles, contours and sectional plots of pressure and film shape near both edge regions are compared. The asymmetric pressure distributions and film shapes show that the EHL results of finite line contacts are highly dependent upon very small amounts of roller misalignment. Especially, the effect of misalignment on the EHL pressure distribution is much higher than the film shapes.

An Adaptive Deinterlacing Algorithm Using a Median Filter (중간값 필터를 이용한 적응적 디인터레이싱 알고리듬)

  • Lee, Sang-Un;Baek, Kyung-Hoon
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.11 no.6
    • /
    • pp.87-91
    • /
    • 2011
  • In this paper, we propose a new deinterlacing method that converts the interlaced images into the progressive images using a field. Firsr of all, it estimates the direction of edge. If it makes an accurate estimate of the direction, then it interpolates a pixel using ELA(Edge-based Line Average). Otherwise, it estimates the new direction of edge, and then,, it interpolates a pixel using a proposed median filter. From simulation results, it is shown that the proposed method improves both subjective and objective image quality as compared with previous deinterlacing methods.