• ETRI Journal
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• v.37 no.4
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• pp.752-765
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• 2015

We propose a novel post-processing algorithm and its very-large-scale integration architecture that simultaneously uses the passive and active stereo vision information to improve the reliability of the three-dimensional disparity in a hybrid stereo vision system. The proposed architecture consists of four steps - left-right consistency checking, semi-2D hole filling, a tiny adaptive variance checking, and a 2D weighted median filter. The experimental results show that the error rate of the proposed algorithm (5.77%) is less than that of a raw disparity (10.12%) for a real-world camera image having a $1,280{\times}720$ resolution and maximum disparity of 256. Moreover, for the famous Middlebury stereo image sets, the proposed algorithm's error rate (8.30%) is also less than that of the raw disparity (13.7%). The proposed architecture is implemented on a single commercial field-programmable gate array using only 13.01% of slice resources, which achieves a rate of 60 fps for $1,280{\times}720$ stereo images with a disparity range of 256.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.1A
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• pp.19-30
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• 2012

Recently, vision-based dynamic deflection measurement techniques have significant interests and are getting more popular owing to development of the high-quality and low-price camcorder and also image processing algorithm. However, there are still several research issues to be improved including the self-vibration of vision device, i.e. camcorder, and the image processing algorithm in device aspect, and also the application area should be extended to measure three dimensional movement of floating structures in application aspect. In this study, vision-based dynamic motion measurement technique using multiple targets is proposed to measure three dimensional dynamic motion of floating structures. And also a new scheme to select threshold value to discriminate the background from the raw image containing targets. The proposed method is applied to measure the dynamic motion of large concrete floating quay in open sea area under several wave conditions, and the results are compared with the measurement results from conventional RTK-GPS(Real Time Kinematics-Global Positioning System) and MRU(Motion Reference Unit).

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.16 no.2
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• pp.131-139
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• 2016

Recognition of human motions has become a main area of computer vision due to its potential human-computer interface (HCI) and surveillance. Among those existing recognition techniques for human motions, head detection and tracking is basis for all human motion recognitions. Various approaches have been tried to detect and trace the position of human head in two-dimensional (2D) images precisely. However, it is still a challenging problem because the human appearance is too changeable by pose, and images are affected by illumination change. To enhance the performance of head detection and tracking, the real-time three-dimensional (3D) data acquisition sensors such as time-of-flight and Kinect depth sensor are recently used. In this paper, we propose an effective feature extraction method, called adaptive local binary pattern (ALBP), for depth image based applications. Contrasting to well-known conventional local binary pattern (LBP), the proposed ALBP cannot only extract shape information without texture in depth images, but also is invariant distance change in range images. We apply the proposed ALBP for head detection and tracking in depth images to show its effectiveness and its usefulness.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1227-1230
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• 2007

This paper describes recent advances in the R&D work achieved at Fraunhofer HHI (Germany) that are believed to provide key technologies for the development of future human-machine interfaces. The paper focus on the area of vision based interaction technologies that will be one essential component in future three-dimensional display systems.

• Proceedings of the KIEE Conference
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• 2005.07d
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• pp.2504-2506
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• 2005

Cross Laser 와 카메라를 이용하여 2차원 영상정보를 통해 대상체의 3차원 정보를 구하는 3차원 계측 시스템을 구현하였다. 주변에서 값싸게 구할 수 있는 USB Web 카메라를 이용하여 50nm 정밀도를 가지는 구현하기 위해 카메라 보정을 실시하였으며 카메라와 레이저광 사이의 보정도 실시하였다. Cross Laser을 사용함으로써 대상체의 평면의 방정식을 구할 수가 있어 대상체의 기울어짐에 대해서도 알 수 있다.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.34C no.10
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• pp.76-88
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• 1997

Based on the principles described in Part I, we have implemented a working prototype vision system using a feature structure called an LSG (local surface group) for generating object hypotheses. In order to verify an object hypothesis, we estimate the view of the hypothesized model object and render the model object for the computed view. The object hypothesis is then verified by finding additional features in the scene that match those present in the rendered image. Experimental results on synthetic and real range images show the effectiveness of the indexing scheme.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.7
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• pp.175-181
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• 1998

This paper describes realtime visual tracking system of moving object for three dimensional target using EKF(Extended Kalman Filter). We present a new realtime visual tracking using EKF algorithm and image prediction algorithm. We demonstrate the performance of these tracking algorithm through real experiment. The experimental results show the effectiveness of the EKF algorithm and image prediction algorithm for realtime tracking and estimated state value of filter, predicting the position of moving object to minimize an image processing area, and by reducing the effect by quantization noise of image.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.766-771
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• 2004

In this paper, new exploration mobile robot is presented. This mobile robot, called Robhaz-6W, is able to overcome hazardous terrains, recognize three dimensional terrain information and generate a path toward the destination by itself. We develop the passive four bar linkage mechanism adoptable to such terrain without any active control and the real time stereo vision system for obstacle avoidance, a remote control and a path planning method. And the geometrical information is transmitted to the operator in the remote site via wireless LAN equipment. And finally, experimental results for the passive mechanism, the real time stereo vision system, the path planning are reported, which show the versatility of the proposed mobile robot system to carry out some tasks.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1739_1740
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• 2009

인간의 몸의 값이 1000냥이라고 하면 그중의 눈의 값은 900냥이라는 말이 있다. 그만큼 눈이 차지하는 즉 시각이 차지하는 비중이 매우 크다고 할 수가 있겠다. 또한 하등동물보다 고등동물로 진화해갈수록 시각의 활용도가 높아지는 것과 같이 각종 기계에 있어서도 자동화가 진전될수록 머신비전(Machine Vision)기술의 의존도 또한 높아지게 되었다. 따라서 산업이 발전함에 따라 머신 비전의 기술은 여러 분야에 걸쳐 요구되고, 연구가 활발히 진행되고 있다. 하지만 기존의 패키지 형식의 머신 비전 시스템은 산업 현장에 적용하는데 가격이 비싸고, 인터페이스 문제, 환경이나 필요조건 및 요구에 의한 시스템의 대처능력이 떨어지는 문제 등을 가지고 있다. 이러한 문제를 해결하기 위한 PC 기반의 머신비젼 시스템에 관한 연구가 필수적일 수 있다. 이러한 점을 궁극적인 목표로 설정하고 본 연구는 산업현장에 적용할 수 있는 머신 비전 시스템의 최적화 설계 에 대한 기술을 연구하였다.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10a
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• pp.776-779
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• 1987

This paper describes a technique for measuring the volume of a pile of powder in a visual way. The volume of a fragile object whose shape is easily transformed by a slight touch of another object must be measured without any contact with it. This can be achieved by applying a three-dimensional shape reconstruction technique employed in computer vision. We have developed a measurement system that finds the volume of a pile of powder by employing a range finder, and performed an experiment of determining the volume of PVC powder piled on a table. The result of the experiment was satisfactory.