• 한국자동차공학회논문집
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• 제11권1호
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• pp.201-210
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• 2003

In this paper, we propose a new binocular stereo correspondence method by maximizing a fitness formulated by integrating two constraints of edge similarity and disparity smoothness simultaneously. The proposed stereopsis focusing to measure distances to leading vehicles on roads uses intensity gradients as matching attribute. In contrast to the previous work of area-based stereo matching, in which matching unit is a pixel, the matching unit of the proposed method becomes an area itself which is obtained by selecting a series of pixels enclosed by two pixels on the left and right boundaries of an object. This approach allows us to cope with real-time processing and to avoid window size selection problems arising from conventional area-based stereo.

• 한국통신학회논문지
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• 제24권12B호
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• pp.2438-2446
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• 1999

대부분의 블록기반 스테레오 쌍 압축 기술들은 모든 스테레오 쌍에서 가장 일치하는 블록을 찾기 위해 일정한 블록크기와 탐색영역 크기를 사용한다. 그러나 각 스테레오 쌍마다 서로 다른 불일치를 가지기 때문에 모든 스테레오 쌍에 동일한 블록 크기와 탐색영역 크기를 적용하는 것은 효과적이지 못하다. 본 논문에서는 스테레오 쌍의 전체 불일치를 구하는 방법을 제시하고 구하여진 전체 불일치를 사용하여 블록기반 스테레오 쌍의 압축에 적용할 블록 크기와 탐색영역 크기를 결정한다.

• 전자공학회논문지B
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• 제33B권2호
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• pp.77-87
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• 1996

Existing area-based stereo matching algorithms utilize a single rectangular correlation area for computing cross-correlation between corresponding points in stereo images, and compute disparity by finding the peak in the vicinity of depth discontinuity, since, because of inconstnat disparities around discontinuities, the cross-correlation becomes low in such area. Inthis paper, a new area-based matching strategy is proposed exploiting multiple directional correlation masks instead of a single one. The proposed technique computes multiple cross-covariance functions using each oriented mask. Peaks are detected from each covariance function and the disparity is computed by choosing the location with the highest covariance value. Proposed approach can also be applied to compute disparity gradients without obtaining dense depth data. A number of examples are presented using synthetic and natural stereo images.

• 대한전기학회논문지:시스템및제어부문D
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• 제53권4호
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• pp.277-285
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• 2004

We present a new hybrid stereo matching technique in terms of the co-operation of area-based stereo and feature-based stereo. The core of our technique is that feature matching is carried out by the reference of the disparity evaluated by area-based stereo. Since the reference of the disparity can significantly reduce the number of feature matching combinations, feature matching error can be drastically minimized. One requirement of the disparity to be referenced is that it should be reliable to be used in feature matching. To measure the reliability of the disparity, in this paper, we employ the self-consistency of the disunity Our suggested technique is applied to the detection of 3D line segments by 2D line matching using our hybrid stereo matching, which can be efficiently utilized in the generation of the rooftop model from urban imagery. We carry out the experiments on our hybrid stereo matching scheme. We generate synthetic images by photo-realistic simulation on Avenches data set of Ascona aerial images. Experimental results indicate that the extracted 3D line segments have an average error of 0.5m and verify our proposed scheme. In order to apply our method to the generation of 3D model in urban imagery, we carry out Preliminary experiments for rooftop generation. Since occlusions are occurred around the outlines of buildings, we experimentally suggested multi-image hybrid stereo system, based on the fusion of 3D line segments. In terms of the simple domain-specific 3D grouping scheme, we notice that an accurate 3D rooftop model can be generated. In this context, we expect that an extended 3D grouping scheme using our hybrid technique can be efficiently applied to the construction of 3D models with more general types of building rooftops.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(4)
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• pp.69-72
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• 2001

This paper proposes a positional estimation method for extracted line features by stereo vision. Based on given reference plane, planar surfaces corresponding the given plane are first extracted. Then, features in the planar surfaces are selected. Using the Extended Kalman Filter the feature positions are estimated by combining area- and feature-based stereo matching results. Experimental results show the proposed method is feasible.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -3
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• pp.1678-1680
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• 2002

Stereo matching technique is used in many practical fields like satellite image analysis and computer vision. In this paper, we suggest a method to extract a target object image from a complicated background. For example, human face image can be extracted from random background. This method can be applied to computer vision such as security system, dressing simulation by use of extracted human face, 3D modeling, and security system. Many researches about stereo matching have been performed. Conventional approaches can be categorized into area-based and feature-based method. In this paper, we start from area-based method and apply area tracking using scanning window. Coarse depth information is used for area merging process using area searching data. Finally, we produce a target object image.

• 디지털콘텐츠학회 논문지
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• 제5권4호
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• pp.257-263
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• 2004

본 논문은 객체 기반 스테레오 정합에 있어서, 분할영역 내부에 존재하는 단계적인 변위의 변화를 추정할 수 있는 스테레오 정합 알고리즘에 관한 것이다. 우산 분할영역을 효과적으로 표현할 수 있는 복수의 샘플점들을 선정한 다음에 각 샘플점 주위에 인접한 영역 내부의 미소영역을 취하여 스테레오 정합을 수행한다. 이후, 선택된 각 샘플점의 변위에 의한 평면의 방정식을 이용하여 내부 변위들을 보간한다. 제안된 방법에 따르면, 샘플점에서 얻어진 변위 값을 영역내부로 전파시킴으로써 깊이 추정이 단지 특징점들에서만 국한되는 특징 기반 기법의 문제점을 해결할 수 있으며, 또한 분할영역의 외곽선에서 샘플점을 추출함으로써 단순 영역에서의 깊이 추정이 모호하게 되는 영역기반 기법의 문제점을 효과적으로 억제시킬 수 있다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.293-293
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• 2010

In this paper, we propose a stereo vision based monitoring concept for passenger's safety on railroad platform. In general, basic concept of stereo image processing technique uses the correlations between left and right images, and extracts additional distance information. It provides easy removal of ambient illumination changes, which has been difficult to achieve with conventional 2D based image processing technique. In the paper, we present developed stereo camera and stereo vision based detection algorithm in order to monitor possible accidents at platform area, and verified the detection performance of proposed system with experimental results.

• 대한원격탐사학회지
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• 제8권1호
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• pp.15-26
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• 1992

This paper describes an implementation of adaptive stereo matching for DBM generation. The matching method of two stereo satellite images to find corresponding points used in this paper is area-based matching, which is usually used in the field of making DBM. Same window size and search area used as in the conventional matching methods and we propose adaptive stereo matching algorithm in this paper. We cluster three areas which are consist of mountainous areas, cultivated areas and cities, and rivers and lakes by using proposed linear feature extracting method. These classified areas are matched by adaptive window size and search area, but rivers and lakes is excluded in this experiment. The matching time is three times faster than conventional methods.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 지능정보 및 응용 학술대회
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• pp.73-76
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• 2008

본 논문에서는 스테레오 영상의 대응점을 찾기 위한 영역 기반 스테레오 정차 기법을 제안한다. 영역 기반 스테레오 정합의 주된 문제점은 윈도우 크기에 따라 다른 결과를 초래한다는 것이다. 지금까지 대부분의 영역기반 정합 기법은 윈도우의 크기를 반복적으로 갱신하는 방법을 사용하였으나, 이는 초기 시차(disparity)에 매우 민감하며 계산 비용도 많이 든다. 이러한 문제를 해결하기 위해, 본 논문에서는 스테레오 영상의 특징 정보를 이용하여 가중치를 생성하고, 각 영상의 대응점을 탐색하여 정합한다. 먼저, 평행하게 설치된 두 대의 카메라로부터 획득된 영상에 대한 에지를 검출하여 특징점을 추출한다. 이를 이용하여 두 영상간의 상관관계를 구하여 가중치 함수를 생성하고, 각 영상에 대한 가중치를 적용한 후, 기준영상에 대한 대응점을 찾아 정합한다. 제안된 방법의 성능을 평가하기 위하여 ground truth가 존재하는 다양한 스테레오 영상을 이용하여 실험하였으며, 실험결과 다양한 영상에서도 적응적인 가중치를 생성함으로써 향상된 결과를 보였다.