• Title/Summary/Keyword: Local feature

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A Region-based Image Retrieval System using Salient Point Extraction and Image Segmentation (영상분할과 특징점 추출을 이용한 영역기반 영상검색 시스템)

  • 이희경;호요성
    • Journal of Broadcast Engineering
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    • v.7 no.3
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    • pp.262-270
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    • 2002
  • Although most image indexing schemes ate based on global image features, they have limited discrimination capability because they cannot capture local variations of the image. In this paper, we propose a new region-based image retrieval system that can extract important regions in the image using salient point extraction and image segmentation techniques. Our experimental results show that color and texture information in the region provide a significantly improved retrieval performances compared to the global feature extraction methods.

MEGH: A New Affine Invariant Descriptor

  • Dong, Xiaojie;Liu, Erqi;Yang, Jie;Wu, Qiang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.7
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    • pp.1690-1704
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    • 2013
  • An affine invariant descriptor is proposed, which is able to well represent the affine covariant regions. Estimating main orientation is still problematic in many existing method, such as SIFT (scale invariant feature transform) and SURF (speeded up robust features). Instead of aligning the estimated main orientation, in this paper ellipse orientation is directly used. According to ellipse orientation, affine covariant regions are firstly divided into 4 sub-regions with equal angles. Since affine covariant regions are divided from the ellipse orientation, the divided sub-regions are rotation invariant regardless the rotation, if any, of ellipse. Meanwhile, the affine covariant regions are normalized into a circular region. In the end, the gradients of pixels in the circular region are calculated and the partition-based descriptor is created by using the gradients. Compared with the existing descriptors including MROGH, SIFT, GLOH, PCA-SIFT and spin images, the proposed descriptor demonstrates superior performance according to extensive experiments.

Robust Feature Description and Matching under Out-of-Plane Rotation using Local Graph (면외 회전에 강인한 지역적 그래프 기반의 특징 기술 및 정합)

  • Lee, Man Hee;Park, In Kyu
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2013.06a
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    • pp.66-67
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    • 2013
  • 본 논문에서는 지역적인 그래프를 이용하여 면 외 회전에 강인한 특징 기술 및 정합 방법에 대하여 제안한다. 특징 기반의 지역적인 그래프의 경우 SURF 등을 이용하여 찾아진 특징 정보에 대하여 특징 사이의 상관관계를 이용하여 지역적인 그래프를 생성함으로써 특징 기술의 적용 범위를 확장할 수 있고 이러한 지역적인 그래프의 정합을 위하여 새로운 비용 함수와 정합 방법을 제안한다. 또한 특징 정합 시 이를 활용하여 정합 후보를 결정함으로써 면 외 회전이 존재하는 영상에 대해 좀 더 강인한 특징 정합 결과를 얻을 수 있고 실험 결과 기존의 특징 정합 방법에 비하여 찾아지는 후보의 개수가 증가하고 찾아진 정합 결과의 정확도가 증가하는 것을 확인할 수 있다.

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Loitering Detection Solution for CCTV Security System (방범용 CCTV를 위한 배회행위 탐지 솔루션)

  • Kang, Joohyung;Kwak, Sooyeong
    • Journal of Korea Multimedia Society
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    • v.17 no.1
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    • pp.15-25
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    • 2014
  • In this paper, we propose a loitering detection using trajectory probability distribution and local direction descriptor for intelligent surveillance system. We use a background modeling method for detecting moving object and extract the motion features from each moving object for making feature vectors. After that, we detect the loitering behavior person using K-Nearest Neighbor classifier. We test the proposed method in real world environment and it can achieve real time and robust detection results.

Derivation and Application of the Green Plan Factors Inherent in the Existing Old Settlements in Local City - Focused on Topdong 'Yangdalmal' - (지방 도시의 옛마을 관련 친환경 계획요소의 추출 및 적용검토 - 청주 탑동 '양달말'을 대상으로-)

  • Chae, Su-Min;Byun, Kyeong Hwa;Kim, Tai Young
    • Journal of the Korean Institute of Rural Architecture
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    • v.14 no.1
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    • pp.115-124
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    • 2012
  • The purpose of this study is to derive and to apply green factors focusing on the existing old settlements, Topdong 'Yangdalmal' in Cheongju City. This study is conducted through literatures and GBCC (Green Building Certification Criteria) review. Literatures cover the traditional characteristics of farming village and the modern characteristics of urban space today. The results are following as; first, Land Use, Environment, Resource and Energy are the most important green factors by literatures and GBCC. Second, traditional elements and natural elements such as history and culture, natural resource use and passive planning are added. Finally information communication is added as the green factor showed feature of modern society.

Extraction of Geometric Primitives from Point Cloud Data

  • Kim, Sung-Il;Ahn, Sung-Joon
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.2010-2014
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    • 2005
  • Object detection and parameter estimation in point cloud data is a relevant subject to robotics, reverse engineering, computer vision, and sport mechanics. In this paper a software is presented for fully-automatic object detection and parameter estimation in unordered, incomplete and error-contaminated point cloud with a large number of data points. The software consists of three algorithmic modules each for object identification, point segmentation, and model fitting. The newly developed algorithms for orthogonal distance fitting (ODF) play a fundamental role in each of the three modules. The ODF algorithms estimate the model parameters by minimizing the square sum of the shortest distances between the model feature and the measurement points. Curvature analysis of the local quadric surfaces fitted to small patches of point cloud provides the necessary seed information for automatic model selection, point segmentation, and model fitting. The performance of the software on a variety of point cloud data will be demonstrated live.

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Charateristics of Adhesive Joint between Concrete and FRP Using Numerical Method (수치 모델을 사용한 콘크리트-FRP 부착면의 거동 특성)

  • 조정래;조근희;박영환;김병석
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.11a
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    • pp.219-222
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    • 2003
  • Substantial experimental and theoretical work exists on the bond characteristics of FRP-concrete adhesive joints. Experimental studies show that the bond strength cannot always increase with an increase in the bond length, and that the ultimate strength is strongly influenced by the concrete strength. To solve this feature, analytic solutions based on fracture mechanics are widely used, and the local shear stress-slip curve with a softening branch is known as more rational model. The analytic solution, however, cannot describe various shapes of model curve. In this study, numerical method using interface element is introduced to express various shapes of model curve. Characteristics of adhesive joint is investigated for the shapes of the model curve and their parameters. And the numerical solutions are compared with the test results of CFRP sheet adhesive joints.

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Linear Discriminant Clustering in Pattern Recognition

  • Sun, Zhaojia;Choi, Mi-Seon;Kim, Young-Kuk
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.717-718
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    • 2008
  • Fisher Linear Discriminant(FLD) is a sample and intuitive linear feature extraction method in pattern recognition. But in some special cases, such as un-separable case, one class data dispersed into several clustering case, FLD doesn't work well. In this paper, a new discriminant named K-means Fisher Linear Discriminant, which combines FLD with K-means clustering is proposed. It could deal with this case efficiently, not only possess FLD's global-view merit, but also K-means' local-view property. Finally, the simulation results also demonstrate its advantage against K-means and FLD individually.

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Color Object Recognition and Real-Time Tracking using Neural Networks

  • Choi, Dong-Sun;Lee, Min-Jung;Choi, Young-Kiu
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.135-135
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    • 2001
  • In recent years there have been increasing interests in real-time object tracking with image information. Since image information is affected by illumination, this paper presents the real-time object tracking method based on neural networks that have robust characteristics under various illuminations. This paper proposes three steps to track the object and the fast tracking method. In the first step the object color is extracted using neural networks. In the second step we detect the object feature information based on invariant moment. Finally the object is tracked through a shape recognition using neural networks. To achieve the fast tracking performance, we have a global search for entire image and then have tracking the object through local search when the object is recognized.

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Vision Based Map-Building Using Singular Value Decomposition Method for a Mobile Robot in Uncertain Environment

  • Park, Kwang-Ho;Kim, Hyung-O;Kee, Chang-Doo;Na, Seung-Yu
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.101.1-101
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    • 2001
  • This paper describes a grid mapping for a vision based mobile robot in uncertain indoor environment. The map building is a prerequisite for navigation of a mobile robot and the problem of feature correspondence across two images is well known to be of crucial Importance for vision-based mapping We use a stereo matching algorithm obtained by singular value decomposition of an appropriate correspondence strength matrix. This new correspondence strength means a correlation weight for some local measurements to quantify similarity between features. The visual range data from the reconstructed disparity image form an occupancy grid representation. The occupancy map is a grid-based map in which each cell has some value indicating the probability at that location ...

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