• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 D
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• pp.2326-2328
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• 2001

This paper's purpose is to obtain 3-Dimension information by using a monocular camera. This system embodies to obtain the height of object by using trigonometry method between a reference point of circumstance and an object. It is possible to build up system regardless of operating system, and then set it up. An comfortable USB port camera is used everywhere without the capture board. The internet can be used by using the applet and JMF everywhere. We regard the camera as a fixed. And we have developed a Real-Time JPEG/RTP Network Camera system using UDP/IP on Ethernet.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.271-275
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• 1996

In this paper, an automatic spot inspection system has been developed for camera target lens using the computer aided vision system. The developed system comprises: light source, magnifying optics, vision camera, XY robot, and a PC. An efficient algotithm for the spot detection has been implemented, thus up tof ew micrometer size spots can be effectively identified in real time. The developed system has been fully interfaced with XY robot systenm, PLCs, thus the practical spot inspection system has been implemented. The system has been applied to a practical camera manufacturing process, and showed its efficiency.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권6호
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• pp.2689-2708
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• 2016

Multi-camera systems which integrate two or more low-cost digital cameras are adopted to reach higher ground coverage and improve the base-height ratio in low altitude remote sensing. To guarantee accurate multi-camera integration, the geometric relationship among cameras must be determined through platform calibration techniques. This paper proposed a combined two-step platform calibration method. In the first step, the static platform calibration was conducted based on the stable relative orientation constraint and convergent conditions among cameras in static environments. In the second step, a dynamic platform self-calibration approach was proposed based on not only tie points but also straight lines in order to correct the small change of the relative relationship among cameras during dynamic flight. Experiments based on the proposed two-step platform calibration method were carried out with terrestrial and aerial images from a multi-camera system combined with four consumer-grade digital cameras onboard an unmanned aerial vehicle. The experimental results have shown that the proposed platform calibration approach is able to compensate the varied relative relationship during flight, acquiring the mosaicing accuracy of virtual images smaller than 0.5pixel. The proposed approach can be extended for calibrating other low-cost multi-camera system without rigorously mechanical structure.

• Journal of Electrical Engineering and Technology
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• 제13권1호
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• pp.438-444
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• 2018

Structured light vision system has been widely used in 3D surface profiling. Usually, it is composed of a camera and a laser which projects a line on the target. Calibration is necessary to acquire 3D information using structured light stripe vision system. Conventional calibration algorithms have found the pose of the camera and the equation of the stripe plane of the laser under the same coordinate system of the camera. Therefore, the 3D reconstruction is only possible under the camera frame. In most cases, this is sufficient to fulfill given tasks. However, they require multiple images which are acquired under different poses for calibration. In this paper, we propose a calibration algorithm that could work by using just one shot. Also, proposed algorithm could give 3D reconstruction under both the camera and laser frame. This would be done by using newly designed calibration structure which has multiple vertical planes on the ground plane. The ability to have 3D reconstruction under both the camera and laser frame would give more flexibility for its applications. Also, proposed algorithm gives an improvement in the accuracy of 3D reconstruction.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.380-383
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• 2003

The purpose of this study is to develope prototype EPID system and improve image quality of radiation therapy field imaging system using CCD camera. For this research we used Linac(Clinac 4/100), Copper metal plate, $Gd_2O_2S_2$ phosphor and CCD camera(Photronic). In this study we find best thickness of buil-up metal plate and acquired projection image of humanoid head phantom. Also we enhanced raw image data using superposition and histogram stretching method. Through the thickness optimized of metal plate and image processing, we confirmed of an improved image quality of an EPID system using CCD camera. As result, highest quality image was acquired at 1mm thickness of Copper metal plate and improved image quality by image processing methods.

• 한국시뮬레이션학회논문지
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• 제18권3호
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• pp.73-82
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• 2009

CMOS 카메라는 저가격, 저전력, 소형화의 장점을 이용해 휴대폰카메라, 자동차 산업, 의학 및 센서 네트워크, 로봇제어, 보안 분야의 연구에서 이용되고 있다. 특히 다중카메라(Multi-Camera)기반의 $360^{\circ}$ 전방향 카메라(Omni-directional Camera)의 소프트웨어, 통신간섭 및 지연과 복잡한 영상제어 문제가 있으며, 하드웨어 분야에서는 다중카메라의 효율적인 관리 및 소형화의 문제를 지닌다. 기존 시스템은 다수 카메라를 제어하고 카메라 영상을 송수신하기 위해 카메라별 고성능 MCU로 구성된 임베디드 시스템(embedded system)과 별도의 제어 시스템(control system) 같이 다계층 시스템(Multi-layer system)으로 구성된다. 하지만 본 시스템은 단일구조로 저성능 MCU 기반에 고속 동기화기법으로 카메라 제어 및 영상 수집이 가능하도록 SLAVS(Small size/Low power Around View System)을 제안하였다. 화각 $110^{\circ}$ CMOS 카메라 여러 대를 이용하여 $360^{\circ}$전방향을 촬영하는 저성능 MCU로 카메라의 제어 및 영상 수집이 가능한 전방향 카메라 초기모형이다. 결과적으로 저전력 CMOS 카메라 4대를 하나의 MCU에 연결하여 개별 카메라에 대한 동기 유지, 제어 및 송수신을 구현하고 이를 기존의 시스템과 비교하였다. MCU를 통한 개별 인터럽트 처리로 카메라별 동기를 제어, 기억하여 Target과 CMOS 카메라와 MCU간의 재동기를 최소화하여 데이터 전송의 효율성을 높였다. 또한, 사용자 선택에 따라 4개의 영역으로 구분된 영상을 각기 또는 하나로 Target에 제공할 수 있도록 하였다. 마지막으로 개발된 카메라 시스템의 동기 및 데이터 전송 시간, 이미지 데이터 유실 등의 성능 비교, 분석을 하였다.

• 한국측량학회지
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• 제27권2호
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• pp.261-271
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• 2009

최근 도시의 3차원 공간정보에 대한 필요성이 증가함에 따라 연직사진과 경사사진을 동시에 촬영하는 항공용 다각카메라에 대한 관심이 높아지고 있다. 기존의 지형공간정보는 주로 연직사진에 의존하지만 다각 카메라는 연직사진 뿐 아니라 사방에서 촬영된 경사사진도 함께 이용하므로 사용자가 대상물을 쉽게 판독할 수 있게 한다. 본 연구에서는 카메라시스템, GPS/INS, 촬영안내시스템, 제어시스템으로 구성된 다각사진촬영시스템 프로토타입을 개발하고, 실제 항공촬영에 통해 장비개발 시 고려해야 할 카메라 설치 각도, 동시촬영, 촬영시간지연, 저장 등에 대해 실험하였다.

• International Journal of Control, Automation, and Systems
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• 제6권5호
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• pp.746-754
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• 2008

This paper proposes a method to detect calibration patterns for accurate camera calibration under complicated backgrounds and uneven lighting conditions of industrial fields. Required to measure object dimensions, the preprocessing of camera calibration must be able to extract calibration points from a calibration pattern. However, industrial fields for visual inspection rarely provide the proper lighting conditions for camera calibration of a measurement system. In this paper, a probabilistic criterion is proposed to detect a local set of calibration points, which would guide the extraction of other calibration points in a cluttered background under irregular lighting conditions. If only a local part of the calibration pattern can be seen, input data can be extracted for camera calibration. In an experiment using real images, we verified that the method can be applied to camera calibration for poor quality images obtained under uneven illumination and cluttered background.

• 전자공학회논문지S
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• 제34S권9호
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• pp.67-76
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• 1997

This ppaer describes the development of the stereo camera system(KASS-1) and the control of the vergence of the stereo camera to fix a gaze on a moving object in real-time using a stereo disparity. The motion energy and the stereo disparity of a moving object from the stereo image are used to control the vergence of stereo camera to keep stereo disparity constant. The disparity from the rotating stereo camera is introduced not only from the moving object but also from the background. In this paper, the background disparity error due to the vergence control of the stereo camera is eliminated by compensation algoithm, and the vergence of steereo camera system can be controlled continuously using the disparity of a moving object only.

• 산업경영시스템학회지
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• 제22권49호
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• pp.135-142
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• 1999

The objective of this paper is to provide an automatic color image testing system capable of synthetically testing a color element like a color tone and a luminance for a color image displayed on the screen, using a CCD camera and a microprocess. The system consists of a CCD camera, a line conveyor, a camera driving part, a remocon, a remote sensing part, a display and a PC including a color vision board and a CPU board. By applying the system to a process, reliability for a testing result can be improved and the absolute criterion to judge a part can be made.