• Title/Summary/Keyword: point matching

Search Result 840, Processing Time 0.043 seconds

Object matching algorithms using robust hausdorff distance measure (Robust hausdorff 거리 척도를 이용한 물체 정합 알고리듬)

  • 권오규;심동규;박래홍
    • Journal of the Korean Institute of Telematics and Electronics S
    • /
    • v.34S no.11
    • /
    • pp.93-101
    • /
    • 1997
  • A Hausdorff distance (HD) is one of commonly used measures for object matching. It calculates the distance between two point sets of edges in two-dimensional binary images without establishing correspondences. This paper proposes three object matching algorithm using robust HD measures based on M-estimation, least trimmed square (LTS), and .alpha.-trimmed mean methods, which are more efficient than the conventional HD measures. By computer simulation with synthetic and real images, the matching performance of the conventional HD smeasures and proposed' robust ones is compared.

  • PDF

A Matching Strategy to Recognize Occluded Number (폐색된 숫자를 인식하는 매칭 방법)

  • Pham, Thi Thuong;Choi, Hyung-Il;Kim, Gye-Young
    • Proceedings of the Korean Society of Computer Information Conference
    • /
    • 2011.01a
    • /
    • pp.55-58
    • /
    • 2011
  • This paper proposes a method of occluded number recognition by matching interest points. Interest points of input pattern are found via SURF features extracting and matched to interest points of clusters in database following three steps: SURF matching, coordinate matching and SURF matching on coordinate matched points. Then the satisfied interest points are counted to compute matching rate of each cluster. The input pattern will be assigned to cluster having highest matching rate. We have experimented our method to different numerical fonts and got encouraging results.

  • PDF

Translation- and Rotation-Invariant Fingerprint Authentication Based on Gabor Features (Gabor 특징에 기반한 이동 및 회전 불변 지문인증)

  • 김종화;조상현;성효경;최홍문
    • Proceedings of the IEEK Conference
    • /
    • 2000.09a
    • /
    • pp.901-904
    • /
    • 2000
  • A direct authentication from gray-scale image, instead of the conventional multi-step preprocessing, is proposed using Gabor filter-based features from the gray-scale fingerprint around core point. The core point is located as a reference point for the translation invariant matching. And its principal symmetry axis is detected for the rotation invariant matching from its neighboring region centered at the core point. And then fingerprint is divided into non-overlapping blocks with respect to the core point and features are directly extracted form the blocked gray level fingerprint using Gabor filter. The proposed fingerprint authentication is based on the Euclidean distance between the corresponding Gabor features of the input and the template fingerprints. Experiments are conducted on 300${\times}$300 fingerprints obtained from a CMOS sensor with 500 dpi resolution, and the proposed method could lower the False Reject Rate(FRR) to 18.2% under False Acceptance Rate(FAR) of 0%.

  • PDF

Fast Block Matching Algorithm With Half-pel Accuracy for Video Compression (동영상 압축을 위한 고속 반화소 단위 블록 정합 알고리듬)

  • 이법기;정원식;김덕규
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.24 no.9B
    • /
    • pp.1697-1703
    • /
    • 1999
  • In this paper, we propose the fast block matching algorithm with half pel accuracy using the lower bound of mean absolute difference (MAD) at search point of half pel accuracy motion estimation. The proposed method uses the lower bound of MAD at search point of half pel accuracy which calculated from MAD's at search points of integer pel accuracy. We can reduce the computational complexity by executing the block matching operation only at the necessary search point. The points are selected when the lower bound of MAD at that point is smaller than reference MAD of integer pel motion estimation. Experimental results show that the proposed method can reduce the computational complexity considerably and keeping the same performance with conventional method.

  • PDF

Accuracy Evaluation by Point Cloud Data Registration Method (점군데이터 정합 방법에 따른 정확도 평가)

  • Park, Joon Kyu;Um, Dae Yong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.38 no.1
    • /
    • pp.35-41
    • /
    • 2020
  • 3D laser scanners are an effective way to quickly acquire a large amount of data about an object. Recently, it is used in various fields such as surveying, displacement measurement, 3D data generation of objects, construction of indoor spatial information, and BIM(Building Information Model). In order to utilize the point cloud data acquired through the 3D laser scanner, it is necessary to make the data acquired from many stations through a matching process into one data with a unified coordinate system. However, analytical researches on the accuracy of point cloud data according to the registration method are insufficient. In this study, we tried to analyze the accuracy of registration method of point cloud data acquired through 3D laser scanner. The point cloud data of the study area was acquired by 3D laser scanner, the point cloud data was registered by the ICP(Iterative Closest Point) method and the shape registration method through the data processing, and the accuracy was analyzed by comparing with the total station survey results. As a result of the accuracy evaluation, the ICP and the shape registration method showed 0.002m~0.005m and 0.002m~0.009m difference with the total station performance, respectively, and each registration method showed a deviation of less than 0.01m. Each registration method showed less than 0.01m of variation in the experimental results, which satisfies the 1: 1,000 digital accuracy and it is suggested that the registration of point cloud data using ICP and shape matching can be utilized for constructing spatial information. In the future, matching of point cloud data by shape registration method will contribute to productivity improvement by reducing target installation in the process of building spatial information using 3D laser scanner.

FIXED POINTS AND ALTERNATIVE PRINCIPLES

  • Park, Se-Hie;Kim, Hoon-Joo
    • Honam Mathematical Journal
    • /
    • v.34 no.3
    • /
    • pp.439-449
    • /
    • 2012
  • In a recent paper, M. Balaj [B] established an alternative principle. The principle was applied to a matching theorem of Ky Fan type, an analytic alternative, a minimax inequality, and existence of solutions of a vector equilibrium theorem. Based on the first author's fixed point theorems, in the present paper, we obtain generalizations of the main result of Balaj [B] and their applications.

Analysis of the Coplanar Waveguide Shielded by Rectangular Waveguide (구형 도파관으로 차폐된 코플래너 도파관 해석)

  • 황정섭;이상설
    • Journal of the Korean Institute of Telematics and Electronics A
    • /
    • v.30A no.7
    • /
    • pp.19-25
    • /
    • 1993
  • By using the point matching method, the coplanar waveguide shielded by the rectangular waveguide has been analyzed. The particular potential solution of C.P.W has been obtained from the boundary condition by using the point matching method. The line capacitance has been obtained from the total charge of the center conductor per length. The effective dielectric constant and the line impedance have been obtained from the line capacitance of C.P.W.

  • PDF

Face Recognition based on SURF Interest Point Extraction Algorithm (SURF 특징점 추출 알고리즘을 이용한 얼굴인식 연구)

  • Kang, Min-Ku;Choo, Won-Kook;Moon, Seung-Bin
    • Journal of the Institute of Electronics Engineers of Korea CI
    • /
    • v.48 no.3
    • /
    • pp.46-53
    • /
    • 2011
  • This paper proposes a SURF (Speeded Up Robust Features) based face recognition method which is one of typical interest point extraction algorithms. In general, SURF based object recognition is performed in interest point extraction and matching. In this paper, although, proposed method is employed not only in interest point extraction and matching, but also in face image rotation and interest point verification. image rotation is performed to increase the number of interest points and interest point verification is performed to find interest points which were matched correctly. Although proposed SURF based face recognition method requires more computation time than PCA based one, it shows better recognition rate than PCA algorithm. Through this experimental result, I confirmed that interest point extraction algorithm also can be adopted in face recognition.

A FAST TEMPLATE MATCHING METHOD USING VECTOR SUMMATION OF SUBIMAGE PROJECTION

  • Kim, Whoi-Yul;Park, Yong-Sup
    • Proceedings of the Korean Society of Broadcast Engineers Conference
    • /
    • 1999.06a
    • /
    • pp.171-176
    • /
    • 1999
  • Template matching is one of the most often used techniques for machine vision applications to find a template of size M$\times$M or subimage in a scene image of size N$\times$N. Most template matching methods, however, require pixel operations between the template and the image under analysis resulting in high computational cost of O(M2N2). So in this thesis, we present a two stage template matching method. In the first stage, we use a novel low cost feature whose complexity is approaching O(N2) to select matching candidates. In the second stage, we use conventional template matching method to find out the exact matching point. We compare the result with other methods in terms of complexity, efficiency and performance. Proposed method was proved to have constant time complexity and to be quite invariant to noise.

A Stereo Matching Method for Photogrammetric Orientation (사진측량의 표정을 위한 스테레오 매칭 방법)

  • 최재화;박희주;서용운
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.14 no.1
    • /
    • pp.9-16
    • /
    • 1996
  • A new stereo matching method for the relative orientation and the photogrammetric triangulation has been pro-posed. It matches the pairs of conjugate points to be used as pass points and tie points in digital aerial photographs instead of selecting these points with manual point transfer and measurements. Three unique steps included in the proposed matching method are as followings. The first step is searching interest points, and designating them as candidate points to be matched. The second is matching the points from the pair of images by the Cross Correlation Method in both direction(left to right direction and right to left). The third is selecting consistent pairs in the both matching directions. Computer programs based on the proposed matching method have been developed, and with digital aerial photographs which have full ground coordinate information tests were performed to know reliabiliy and positional accuracy of proposed method. Results of the tests reveal that the proposed matching method can eliminate the in-correctly matched pairs more efficiently than other matching methods, thus this can be more reliably applied to the relative orientation and the photogrammetric triangulation.

  • PDF