• Journal of KIISE:Software and Applications
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• v.31 no.11
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• pp.1534-1542
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• 2004

A novel vision-based scheme of extracting real-time traffic information parameters is presented. The method is based on a region classification followed by a spatio-temporal image analysis. The detection region images for each traffic lane are classified into one of the three categories: the road, the vehicle, and the shadow, using statistical and structural features. Misclassification in a frame is corrected by using temporally correlated features of vehicles in the spatio-temporal image. Since only local images of detection regions are processed, the real-time operation of more than 30 frames per second is realized without using dedicated parallel processors, while ensuring detection performance robust to the variation of weather conditions, shadows, and traffic load.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.2C
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• pp.78-85
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• 2011

In this paper we proposed an intelligent PTZ camera system which detects, classifies and tracks moving objects. If a moving object is detected, features are extracted for classification and then realtime tracking follows. We used GMM for detection followed by shadow removal. Legendre moment is used for classification. Without auto focusing, we can control the PTZ camera movement by using center points of the image and object's direction, distance and velocity. To implement the realtime system, we used TI DM6446 Davinci processor. Throughout the experiment, we obtained system's high performance in classification and tracking both at vehicle's normal and high speed motion.

• Journal of the Semiconductor & Display Technology
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• v.10 no.2
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• pp.31-38
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• 2011

This paper introduces a video based traffic monitoring system for detecting vehicles and obstacles on the road. To segment moving objects from image sequence, we adopt the background subtraction algorithm based on the local binary patterns (LBP). Recently, LBP based texture analysis techniques are becoming popular tools for various machine vision applications such as face recognition, object classification and so on. In this paper, we adopt an extension of LBP, called the Diagonal LBP (DLBP), to handle the background subtraction problem arise in vision-based autonomous parking systems. It reduces the code length of LBP by half and improves the computation complexity drastically. An edge based shadow removal and blob merging procedure are also applied to the foreground blobs, and a pose estimation technique is utilized for calculating the position and heading angle of the moving object precisely. Experimental results revealed that our system works well for real-time vehicle localization and tracking applications.

• Journal of Mechanical Science and Technology
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• v.19 no.6
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• pp.1290-1303
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• 2005

In this research, a remote control system has been developed and implemented, which combines autonomous obstacle avoidance in real-time with force-reflective tele-operation. A tele-operated mobile robot is controlled by a local two-degrees-of-freedom force-reflective joystick that a human operator holds while he is monitoring the screen. In the system, the force-reflective joystick transforms the relation between a mobile robot and the environment to the operator as a virtual force which is generated in the form of a new collision vector and reflected to the operator. This reflected force makes the tele-operation of a mobile robot safe from collision in an uncertain and obstacle-cluttered remote environment. A mobile robot controlled by a local operator usually takes pictures of remote environments and sends the images back to the operator over the Internet. Because of limitations of communication bandwidth and the narrow view-angles of the camera, the operator cannot observe shadow regions and curved spaces frequently. To overcome this problem, a new form of virtual force is generated along the collision vector according to both distance and approaching velocity between an obstacle and the mobile robot, which is obtained from ultrasonic sensors. This virtual force is transferred back to the two-degrees-of-freedom master joystick over the Internet to enable a human operator to feel the geometrical relation between the mobile robot and the obstacle. It is demonstrated by experiments that this haptic reflection improves the performance of a tele-operated mobile robot significantly.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.5 no.1
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• pp.1-6
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• 2012

In this paper, we propose a HMM(Hidden Markov Model)-based segmentation method to model shadows as well as foreground and background regions. The shadow of moving objects often keeps from visual tracking. We propose an HMM-based segmentation method which classifies each object in real time. In the case of traffic monitoring movies, the effectiveness of the proposed method was proved by experiments.

• Journal of Advanced Marine Engineering and Technology
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• v.19 no.3
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• pp.9-23
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• 1995

To analyze the spray and flame in D.I. diesel engine, the visualizing methods by schlieren photograph and diffused background illumination photograph with high speed camera are applied to optically accessible D.I.diesel engine. Wcaporating spray, spray droplets and brightness flame are taken with high speed camera by visuallizing method in accordance with various suction air temperature and injection time. The spray and flame image on the film was analyzed by image analyzer. The optically accessible D.I. diesel engine had the similar pressure characteristic to the real D.I. diesel engine. Experimental results showed that shadow areas of the evaporating spray were extended at higher suction air temperature, spray droplets had a max. Penetration length and their penetrating patterns were dependent on the surrounding gas temperature, and flame size after ignition was largely governed by the evaporated fuel quantity at ignition point and by the surrounding gas condition due to piston motion.

• Proceedings of the Korean Information Science Society Conference
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• 2010.06b
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• pp.446-450
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• 2010

다변측량법은 위치가 알려진 3개 이상의 지점으로부터 대상까지의 거리 정보를 바탕으로 대상의 위치를 계산하는 기법이다. Real Time Locating Systems (RTLS) 에서는 대상의 위치를 파악하기 위해 다변측량 기법을 주로 사용하는데, 이를 위해서는 리더와 대상과의 거리 정보가 3개 이상 필요하다. 그러나 항만 환경처럼 시설물 설치가 어렵고 장애물도 많은 넓은 지역에서는 음영지역이 다수 존재하여 이러한 조건을 항상 만족시키기 어렵다. 본 논문에서는 다변측량이 불가능한 적은 수의 거리 정보만으로 대상의 위치를 파악할 수 있도록 대상의 동선 정보를 이용하는 동선 정보 기반의 측위 기법을 제안한다. 성능 평가 결과 최소자승법만을 사용했을 때보다 평균 측위 오차가 약 3m, 표준 편차가 6m 줄었으며, 측위 성공률이 4.6 배 이상 높아졌다.

• Proceedings of the Korean Information Science Society Conference
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• 2000.04b
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• pp.628-630
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• 2000

3D 컴퓨터 그래픽스에서 그림자는 매우 중요한 요소이다. 그림자가 없으며 물체와 물체간의 정확한 위치를 파악하기가 어렵기 때문이다. 즉 물체가 다른 물체에 바로 붙어 있는지 조금 떨어져 있는지를 알아내기가 곤란한 것이다. 이러한 그림자의 중요성에도 불구하고 현존하는 3D 가속 하드웨어들은 그림자의 생성을 전혀 지원하지 못하고 있다. 또한, 이것을 보완하기 위해 많은 그림자 생성 알고리즘들이 제시되었지만 모두 그 한계가 명확하였다. 많은 그림자 생성 기법 중 텍스춰 하드웨어를 이용한 그림자 지도 기법은 광원과 물체가 고정되어 있을 경우 매우 빠른 속도로 그림자를 생성시킬 수 있지만 과원이나 물체가 움직일 경우에는 속도가 느려지게 된다. 본 논문에서는 그림자 지도 기법에 영상기반 렌더링 기법을 적용하여 실시간으로 그림자를 생성하고자 하였다. 본 논문의 기법은 매우 많은 메모리를 필요로 하기 때문에 데이터를 적당히 샘플링하여 웨이블릿 기반 압축 기법으로 압축하였고, 그림자를 생성할 때는 가장 가까운 저장된 그림자들을 2차원 보강하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05b
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• pp.587-590
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• 2004

In this paper proposed a HMM(Hidden Martov Model)-based segmentation method which is able to model shadows as well as foreground and background regions. Shadow of moving objects often obstruct visual tracking. We propose an HMM-based segmentation method which classifies in real time oath objects. In the case of traffic monitoring movies, the effectiveness of the proposed method has been proven through experimental results

• Journal of Information Processing Systems
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• v.15 no.5
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• pp.1218-1230
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• 2019

This study proposes a novel video traffic flow detection method based on machine vision technology. The three-frame difference method, which is one kind of a motion evaluation method, is used to establish initial background image, and then a statistical scoring strategy is chosen to update background image in real time. Finally, the background difference method is used for detecting the moving objects. Meanwhile, a simple but effective shadow elimination method is introduced to improve the accuracy of the detection for moving objects. Furthermore, the study also proposes a vehicle matching and tracking strategy by combining characteristics, such as vehicle's location information, color information and fractal dimension information. Experimental results show that this detection method could quickly and effectively detect various traffic flow parameters, laying a solid foundation for enhancing the degree of automation for traffic management.