• Title/Summary/Keyword: Hausdorff 거리

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Efficient Hausdorff Distance Computation for Planar Curves (평면곡선에 대한 Hausdorff 거리 계산의 가속화 기법에 대한 연구)

  • Kim, Yong-Joon;Oh, Young-Taek;Kim, Myung-Soo
    • Korean Journal of Computational Design and Engineering
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    • v.15 no.2
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    • pp.115-123
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    • 2010
  • We present an efficient algorithm for computing the Hausdorff distance between two planar curves. The algorithm is based on an efficient trimming technique that eliminates the curve domains that make no contribution to the final Hausdorff distance. The input curves are first approximated with biarcs within a given error bound in a pre-processing step. Using the biarc approximation, the distance map of an input curve is then approximated and stored into the graphics hardware depth-buffer by rendering the distance maps (represented as circular cones) of the biarcs. We repeat the same procedure for the other input curve. By sampling points on each input curve and reading the distance from the other curve (stored in the hardware depth-buffer), we can easily estimate a lower bound of the Hausdorff distance. Based on the lower bound, the algorithm eliminates redundant curve segments where the exact Hausdorff distance can never be obtained. Finally, we employ a multivariate equation solver to compute the Hausdorff distance efficiently using the remaining curve segments only.

Study on Method for Measuring Partial Hausdorff Distance between Spatial Objects for Updating GIS OB (GIS DB 갱신을 위한 공간 객체간 Partial Hausdorff Distance 측정 방법 연구)

  • Bang, Yoon-Sik;Huh, Yong;Choi, Jae-Wan;Yu, Ki-Yun
    • Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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    • 2008.06a
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    • pp.419-426
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    • 2008
  • 본 논문에서는, 건설도면의 건물 경계선을 이용하여 기존 지형도의 건물 레이어를 자동 갱신하는 과정에서 건물 객체간 유사를 측정하는 과정에서 Hausdorff 거리 측정 방법을 적용해 보았다. 서로 다른 축척에 의하여 발생하는 형상의 세일도 차이에서 발생하는 오차를 최소화하기 위하여 partial Hausdorff 거리를 적용하였다. 이 때 partial fraction을 정의하기 위한 기준으로 폴리곤 절점, 경계선 길이, 폴리곤 면적을 이용한 세 가지 방법을 적용하였다. 이 기준을 실제 데이터에 적용한 결과, 경계선 기준과 폴리곤 면적 기준 방법이 절점 기준에 비하여 안정적이라는 것과, 적용 기준에 따라 적절한 partial fraction 값을 사용하면 잡음에 의한 영향을 최소화할 수 있다는 것을 확인할 수 있었다.

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Research on the Development of Distance Metrics for the Clustering of Vessel Trajectories in Korean Coastal Waters (국내 연안 해역 선박 항적 군집화를 위한 항적 간 거리 척도 개발 연구)

  • Seungju Lee;Wonhee Lee;Ji Hong Min;Deuk Jae Cho;Hyunwoo Park
    • Journal of Navigation and Port Research
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    • v.47 no.6
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    • pp.367-375
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    • 2023
  • This study developed a new distance metric for vessel trajectories, applicable to marine traffic control services in the Korean coastal waters. The proposed metric is designed through the weighted summation of the traditional Hausdorff distance, which measures the similarity between spatiotemporal data and incorporates the differences in the average Speed Over Ground (SOG) and the variance in Course Over Ground (COG) between two trajectories. To validate the effectiveness of this new metric, a comparative analysis was conducted using the actual Automatic Identification System (AIS) trajectory data, in conjunction with an agglomerative clustering algorithm. Data visualizations were used to confirm that the results of trajectory clustering, with the new metric, reflect geographical distances and the distribution of vessel behavioral characteristics more accurately, than conventional metrics such as the Hausdorff distance and Dynamic Time Warping distance. Quantitatively, based on the Davies-Bouldin index, the clustering results were found to be superior or comparable and demonstrated exceptional efficiency in computational distance calculation.

Fast Fingerprint Alignment Method using Local Ridge Direction (지역적 융선의 방향성을 이용한 빠른 지문 정렬 방법)

  • 문성림;김동윤;정석재
    • Proceedings of the Korean Information Science Society Conference
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    • 2003.10b
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    • pp.580-582
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    • 2003
  • 특징점 기반 지문 인식 방법은 지문 영상의 전처리 과정을 포함한 특징점 추출 과정과 추출된 특징점들의 유사도를 판단하는 정합 과정으로 구성된다. 특징점들의 정합과정을 수행하는 여러 가지 방법들 중 Hausdorff 거리 기반 정합 방법은 이동과 회전이 적은 지문의 특징점들에 대해 빠르게 계산할 수 있는 장점을 갖는다. 그러나, 이 방법은 이동과 회전이 많은 지문 영상의 경우 연산이 많아지는 단점을 가진다. 본 논문에서는 정합을 실행하기 전 지문의 중심점과 지역적인 블럭들의 방향성을 기준으로 정렬을 수행하여 비교되는 지문 특징점간의 회전 오차와 이동 오차를 줄임으로써, 기존의 정합 방법의 불필요한 연산량을 줄일 수 있는 방법을 제안하였다. 제안된 방법을 검증하기 위해 Hausdorff 거리 기반 정합 방법을 구현하고 그것에 대한 결과와 선정렬을 사용한 후의 정합 결과를 실험, 비교하였다. 이때의 평균 Hausdorff 거리는 Genuine의 경우 0.095가 줄어들었고, Improster의 경우 0.655가 늘어나는 성능 향상을 나타냈다.

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Hausdorff Distance Matching for Elevation Map-based Global Localization of an Outdoor Mobile Robot (실외 이동로봇의 고도지도 기반의 전역 위치추정을 위한 Hausdorff 거리 정합 기법)

  • Ji, Yong-Hoon;Song, Jea-Bok;Baek, Joo-Hyun;Ryu, Jae-Kwan
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.9
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    • pp.916-921
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    • 2011
  • Mobile robot localization is the task of estimating the robot pose in a given environment. This research deals with outdoor localization based on an elevation map. Since outdoor environments are large and contain many complex objects, it is difficult to robustly estimate the robot pose. This paper proposes a Hausdorff distance-based map matching method. The Hausdorff distance is exploited to measure the similarity between extracted features obtained from the robot and elevation map. The experiments and simulations show that the proposed Hausdorff distance-based map matching is useful for robust outdoor localization using an elevation map. Also, it can be easily applied to other probabilistic approaches such as a Markov localization method.

Robust Oriented Hausdorff Measure for 2-D Object Matching (이차원 물체 정합을 위한 Robust Oriented Hausdorff Measure)

  • Sim, Dong-Gyu;Park, Rae-Hong
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.11
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    • pp.60-67
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    • 1999
  • This paper proposes a robust oriented Hausdorff measure (ROHM) for 20D object matching. The ROHM is introduced by replacing the distance concept of the conventional Hausdorff distance (HD) algorithm by the accumulation scheme of the Hough transform (HT). The proposed algorithm can be considered as the modified directed HT using the distance transform (DT). The orientation information at each pixel is also used for removing incorrect correspondences. Experiments with various test images show that the performance of the proposed algorithm is better than that of conventional HD algorithms considered.

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Character Matching Using a Hausdorff Distance (Hausdorff 거리를 이용한 문자 매칭)

  • Kim, Kyeongtaek;Kyung, Ji Hun
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.38 no.2
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    • pp.56-62
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    • 2015
  • The Hausdorff distance is commonly used as a similarity measure between two-dimensional binary images. Since the document images may be contaminated by a variety of noise sources during transmission, scanning or conversion to digital form, the measure should be robust to the noise. Original Hausdorff distance has been known to be sensitive to outliers. Transforming the given image to grayscale image is one of methods to deal with the noises. In this paper, we propose a Hausdorff distance applied to grayscale images. The proposed method is tested with synthetic images with various levels of noises and compared with other methods to show its robustness.

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
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    • v.34S no.11
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    • pp.93-101
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    • 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.

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Tracking Moving Object using Hausdorff Distance (Hausdorff 거리를 이용한 이동물체 추적)

  • Kim, Tea-Sik;Lee, Ju-Shin
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.37 no.3
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    • pp.79-87
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    • 2000
  • In this paper, we propose a model based moving object tracking algorithm In dynamic scenes To adapt shape change of the moving object, the Hausdorff distance is applied as the measurement of similarity between model and image To reduce processing time, 2D logarithmic search method is applied for locate the position of moving object Experiments on a running vehicle and motorcycle, the result showed that the mean square error of real position and tracking result is 1150 and 1845; matching times are reduced average 1125times and 523 times than existing algorithm for vehicle image and motorcycle image, respectively It showed that the proposed algorithm could track the moving object accurately.

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Construction of moving object tracking framework with fuzzy clustering, prediction and Hausdorff distance (퍼지 군집, 예측과 하우스돌프 거리를 이용한 이동물체 추적 프레임워크 구축)

  • 소영성
    • Journal of the Korean Institute of Intelligent Systems
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    • v.8 no.2
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    • pp.128-133
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    • 1998
  • In this paper, we present a parallel framework for tracking moving objects. Parallel framework consists largely of two parts:Search Space Reduction(SSR) and Tracking(TR). SSR is further composed of fuzzy clustering and prediction based on Kalman filter. TR is done by boundarymatching using the Hausdorff distance based on distance transform.

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