• 제목/요약/키워드: matching points

검색결과 705건 처리시간 0.036초

Point Pattern Matching Algorithm Using Unit-Circle Parametrization

  • Choi, Nam-Seok;Lee, Byung-Gook;Lee, Joon-Jae
    • 한국멀티미디어학회논문지
    • /
    • 제13권6호
    • /
    • pp.825-832
    • /
    • 2010
  • This paper presents only a matching algorithm based on Delaunay triangulation and Parametrization from the extracted minutiae points. This method maps local neighborhood of points of two different point sets to unit-circle using topology information by Delaunay triangulation method from feature points of real fingerprint. Then, a linked convex polygon that includes an interior point is constructed as one-ring which is mapped to unit-circle using Parametrization that keep shape preserve. In local matching, each area of polygon in unit-circle is compared. If the difference of two areas are within tolerance, two polygons are consider to be matched and then translation, rotation and scaling factors for global matching are calculated.

에지 정보와 밝기 정보를 이용한 특징 기반 정합 (Feature based matching using edge and intensity)

  • 김정호;엄기문;이쾌희
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1993년도 하계학술대회 논문집 A
    • /
    • pp.414-417
    • /
    • 1993
  • The methods for stereo matching are divided into two techniques: area-based matching and feature-based matching. To find corresponding points by area-based method, it takes a lot of time because there are many points to be matched. Feature-based matching algorithm is often used because with this method it matches only some feature points so that the processing time is fast even though it requires interpolation after matching. In this paper, we propose the smart technique by which we makes features simpler than conventional methods to match an image pair by feature-based matching algorithm.

  • PDF

Highly Dense 3D Surface Generation Using Multi-image Matching

  • Noh, Myoung-Jong;Cho, Woo-Sug;Bang, Ki-In
    • ETRI Journal
    • /
    • 제34권1호
    • /
    • pp.87-97
    • /
    • 2012
  • This study presents an automatic matching method for generating a dense, accurate, and discontinuity-preserved digital surface model (DSM) using multiple images acquired by an aerial digital frame camera. The proposed method consists of two main procedures: area-based multi-image matching (AMIM) and stereo-pair epipolar line matching (SELM). AMIM evaluates the sum of the normalized cross correlation of corresponding image points from multiple images to determine the optimal height of an object point. A novel method is introduced for determining the search height range and incremental height, which are necessary for the vertical line locus used in the AMIM. This procedure also includes the means to select the best reference and target images for each strip so that multi-image matching can resolve the common problem over occlusion areas. The SELM extracts densely positioned distinct points along epipolar lines from the multiple images and generates a discontinuity-preserved DSM using geometric and radiometric constraints. The matched points derived by the AMIM are used as anchor points between overlapped images to find conjugate distinct points using epipolar geometry. The performance of the proposed method was evaluated for several different test areas, including urban areas.

형상 정합을 통한 변환 파라미터 추출 (Estimation of transformation parameters using shape matching)

  • 박용희;전병호;김태균
    • 한국통신학회논문지
    • /
    • 제22권7호
    • /
    • pp.1523-1533
    • /
    • 1997
  • Image registration is concerned with the establishment of correspondence between images of the same scene with translational, rotational, and scaling differences. The estimated transformation parameters between images are very important information in the field of many applications. In this paper, we propose a shape matching scheme for finding correspondence points for images with various differences, Tranditional solutions to this area are unreliable for the rotational and schaling changes between images, and the feature extraction of partially occluded scene. To solve those problems, dominant points on digital curves are detected by scale-space filtering, and initial matching is performed by similarity measure of cumulative curvatures for dominant points. For initial matching segments pairs, optimal matching points are calculated using dynamic programming.Finally, transformation parameters are estimated.

  • PDF

The Comparison of the SIFT Image Descriptor by Contrast Enhancement Algorithms with Various Types of High-resolution Satellite Imagery

  • Choi, Jaw-Wan;Kim, Dae-Sung;Kim, Yong-Min;Han, Dong-Yeob;Kim, Yong-Il
    • 대한원격탐사학회지
    • /
    • 제26권3호
    • /
    • pp.325-333
    • /
    • 2010
  • Image registration involves overlapping images of an identical region and assigning the data into one coordinate system. Image registration has proved important in remote sensing, enabling registered satellite imagery to be used in various applications such as image fusion, change detection and the generation of digital maps. The image descriptor, which extracts matching points from each image, is necessary for automatic registration of remotely sensed data. Using contrast enhancement algorithms such as histogram equalization and image stretching, the normalized data are applied to the image descriptor. Drawing on the different spectral characteristics of high resolution satellite imagery based on sensor type and acquisition date, the applied normalization method can be used to change the results of matching interest point descriptors. In this paper, the matching points by scale invariant feature transformation (SIFT) are extracted using various contrast enhancement algorithms and injection of Gaussian noise. The results of the extracted matching points are compared with the number of correct matching points and matching rates for each point.

하도를 이용한 오수혈 오행배속 원리 고찰 (A Short Review on the Principal of Matching Five-Su-Points to O-Haeng Using Hado)

  • 최인서;이봉효
    • Korean Journal of Acupuncture
    • /
    • 제31권2호
    • /
    • pp.49-55
    • /
    • 2014
  • Objectives : Five transport points are often used in acupuncture treatment. However, there is no clear explanation about the reason why the five transport points are matched five phases in this manner. Therefore, we reviewed the literatures and theses about the principal of matching and researched a new way to understand the reason. Methods : We found 8 theses and 3 literatures related to the matching of five transport points to five phases by searching the web sites. And, we reviewed the principal of matching and researched another new way to understand the reason why they are matched so. Results and Conclusions : In the viewpoint of the natural state and function of five phases, the start points arising in yin- and yang-meridian are matched to wood and metal respectively. Therefore, well point matches the wood and metal in yin- and yang-meridian respectively. And by following the flow of five transport points, the other points match with fire, earth, metal, water in yin-meridian and water, wood, fire, and earth in yang-meridian.

3차원 정보를 얻기 위한 Rule-Based Stereo Matching Algorithm (A Rule-Based Stereo Matching Algorithm to Obtain Three Dimesional Information)

  • 심영석;박성한
    • 대한전자공학회논문지
    • /
    • 제27권1호
    • /
    • pp.151-163
    • /
    • 1990
  • In this paper, rule-based stereo algorithm is explored to obtain three dimensional information of an object. In the preprocessing of the stereo matching, feature points of stereo images must be less sensitive to noise and well linked. For this purpose, a new feature points detection algorithm is developed. For performing the stereo matching which is most important process of the stereo algorithm, the feature representation of feature points is first described. The feature representation is then used for a rule-based stereo algorithm to determine the correspondence between the input stereo images. Finally, the three dimensional information of the object is determined from the correspondence of the feature points of right and left images.

  • PDF

실내·외 조도에 따른 스테레오 CCTV 영상 정합점 수 변화 (Changes in the Number of Matching Points in CCTV's Stereo Images by Indoor/Outdoor Illuminance)

  • 문광일;편무욱;김종화;김강산
    • 대한공간정보학회지
    • /
    • 제23권1호
    • /
    • pp.129-135
    • /
    • 2015
  • 도시기반시설에 첨단 정보통신기술을 융합하여 언제 어디서나 자유롭게 서비스를 제공하고자 하는 U-City(Ubiquitous City)의 공간정보기술은 다양한 형태로 서비스 되고 있다. 그 중에서도 U-City에서 가장 많이 설치되어 있는 CCTV(Closed Circuit TV)의 스테레오 영상을 가지고 특징점(Key Point)을 선정하여 정합(Matching)하고 3차원 공간정보를 구축하는 연구가 진행되고 있다. 하지만 대부분 정합점을 추출하는데 사용된 데이터는 조도와 같은 외부 환경영향을 고려하지 않고 있다. 본 논문은 동일한 하드웨어에서 조도의 변화에 의해 영상의 질이 좌우되는 CCTV를 가지고 3차원 공간정보를 구축하는데 필요한 정합점이 조도에 따라 얼마나 변화 하는지 실험을 하였다. 조도에 따른 정합점 수의 분석 결과, 카메라의 조리개, 셔터속도, 감도를 고정하였을 때 3,000Lux까지 정합점 수가 조도에 비례하여 높아 졌으며, 물체와 배경의 경계가 뚜렷해졌다. 반대로 빛이 과도하게 들어 왔을 경우 화면이 밝이지며, 노이즈가 발생하고 사물과 사물의 경계가 없어져 특징점을 선정하기가 힘들었다. 본 논문에서 얻어진 결과를 이용하여 촬영할 경우 향상된 정합점을 가질 수 있을 것으로 기대된다.

가변 윈도우의 투영왜곡을 고려한 스테레오 정합 알고리듬 (A Stereo Matching Algorithm with Projective Distortion of Variable Windows)

  • 김경범;정성종
    • 대한기계학회논문집A
    • /
    • 제25권3호
    • /
    • pp.461-469
    • /
    • 2001
  • Existing area-based stereo algorithms rely heavily on rectangular windows for computing correspondence. While the algorithms with the rectangular windows are efficient, they generate relatively large matching errors due to variations of disparity profiles near depth discontinuities and doesnt take into account local deformations of the windows due to projective distortion. In this paper, in order to deal with these problems, a new correlation function with 4 directional line masks, based on robust estimator, is proposed for the selection of potential matching points. These points is selected to consider depth discontinuities and reduce effects on outliers. The proposed matching method finds an arbitrarily-shaped variable window around a pixel in the 3d array which is constructed with the selected matching points. In addition, the method take into account the local deformation of the variable window with a constant disparity, and perform the estimation of sub-pixel disparities. Experiments with various synthetic images show that the proposed technique significantly reduces matching errors both in the vicinity of depth discontinuities and in continuously smooth areas, and also does not be affected drastically due to outlier and noise.

운동영역의 상관성을 선택적으로 이용한 고속 움직임 추정 기법 (Fast Hierarchical Block Matching Algorithm by Adaptively Using Spatial Correlation of Motion Field)

  • 임경원;송병철;나종범
    • 한국방송∙미디어공학회:학술대회논문집
    • /
    • 한국방송공학회 1996년도 학술대회
    • /
    • pp.217-220
    • /
    • 1996
  • This paper describes a new hierarchial block matching algorithm especially appropriate for a large search area. The proposed algorithm consists of higher level search for an initial motion vector estimate by using a new matching criterion over the evenly subsampled search points, and lower level search for the final motion vector refinement. In the higher level matching criterion, mean absolute differences at the search points (or motion vector candidates) similar to motion vectors of causally neighboring blocks, are weighted properly so that these points can have a higher chance to being selected. The proposed algorithm outperforms existing hierarchical block matching algorithms, and its computational regularity makes hardware implementation simple.

  • PDF