• International Journal of Contents
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• 제6권4호
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• pp.49-56
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• 2010

In this paper we present a system that enables the user to interact with large display system even without touching the screen. With two infrared sensitive cameras mounted on the bottom left and bottom right of the display system pointing upwards, the user fingertip position on the selected region of interest of each camera view is found using vertical intensity profile of the background subtracted image. The position of the finger in two images of left and right camera is mapped to the display screen coordinate by using pre-determined matrices, which are calculated by interpolating samples of user finger position on the images taken by pointing finger over some known coordinate position of the display system. The screen is then manipulated according to the calculated position and depth of the fingertip with respect to the display system. Experimental results demonstrate an efficient, robust and stable human computer interaction.

• 한국안전학회지
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• 제35권4호
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• pp.9-14
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• 2020

It is necessary to apply a non-contact high-speed scanning system that can measure in real time in order to prevent the dropping and deformation of the main parts of railway vehicles during high-speed running. Recently, research on a scanning system that detects the deformation state of main parts from a video image taken using a high-performance camera has been actively pursued. In this study, we researched an analysis algorithm of a high-speed scanning system that uses a high-performance camera to monitor the deformation and drop-out state of the main components of the running units equipment in real time.

• 방송공학회논문지
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• 제19권4호
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• pp.533-546
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• 2014

본 논문은 Time-of-Flight(ToF) 깊이 카메라와 DSLR을 이용한 사진측량 기반의 복합형 카메라시스템 구성방법을 제안한다. ToF 깊이 카메라는 깊이 정보를 실시간으로 출력하는 장점이 있지만 제공되는 명암 영상의 해상도가 낮고 획득한 깊이 정보가 물체의 표면상태에 민감하여 잡음이 발생하는 단점이 있다. 따라서 깊이 카메라를 이용한 입체 모델 생성을 위해선 깊이 정보의 보정과 함께 고해상도 텍스처맵을 제공하는 복합형 카메라의 구성이 필요하다. 이를 위해 본 논문은 상대표정을 수행하여 깊이 카메라와 DSLR의 상대적인 기하관계를 추정하고 공선조건식 기반의 역투영식을 이용하여 텍스처매핑을 수행한다. 성능검증을 위해 기존 기법의 모델 정확도와 텍스처매핑 정확도를 비교 분석한다. 실험결과는 제안 기법의 모델 정확도가 더 높았는데 이는 기존 기법이 깊이 카메라의 잡음이 있는 3차원 정보를 기준점으로 사용하여 절대표정을 수행한 반면에 제안 기법은 오차정보가 없는 두 영상간의 공액점을 이용했기 때문이다.

• 한국재난정보학회 논문집
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• 제10권1호
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• pp.105-115
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• 2014

본 연구에서는 지능형 CCTV를 이용하여 자동 수위감지 알고리즘과 사전 경보시스템을 개발하고 Test-Bed에 적용하여 실용화 가능성을 검증하고자 한다. 이를 위하여 현장여건에 적합한 지능형 CCTV 기반의 자동 수위감지 알고리즘을 개발하고 자동인식률 가변 요소에 대한 성능저하 방지대책을 수립하여 CCTV 카메라 기종별 수위감지 성능과 적합성을 평가하고 실용화에 따른 최적 적용방안을 도출한다. 그 결과, CCTV 카메라 기종별 수위감지 성능이 90%으로 도출되었다. CCTV 카메라 기종에 따른 적합성 평가 결과, 자동 수위감지용으로 NIR카메라가 정밀도에서 주 야간 95%이상의 성능을, 떨림 안개 저조도 등 자연환경에서 가장 우수한 성능을, 설치용이성에서는 일반카메라와 대등한 성능을, 가격측면에서 일반카메라 대비 15% 최소 상승분으로 가장 우수했다. 따라서 본 연구개발의 성과물인 지능형 CCTV를 이용한 수위감지 경보시스템의 실용화 가능성을 확인하였으며 향후 실용화가 예상된다.

• 한국정밀공학회지
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• 제21권8호
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• pp.73-82
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• 2004

In this paper, implementation of obstacle avoidance of a nonholonomic mobile robot in unstructured environment is introduced. To avoid obstacles, first, a reference collision-free path for the MR is generated off-line using HJB-based optimal path planning method. A controller is designed using integrator backstepping method for tracking the generated reference path. To implement the designed controller, a control system are needed and composed of camera system and PIC-based controller. The workspace is observed by a ceiling-mounted USB camera as part of an un-calibrated camera system. Thus the positional information of the MR is updated frequently and the MR can get the useful inputs for its tracking controller. The whole control system is realized by integrating a computer with PIC-based microprocessor using wireless communication: the image processing control module and path planning module serve as high level computer control while the device control serves as low level PIC microprocessor control. The simulation and experimental results show the effectiveness of the designed control system.

• Journal of the Optical Society of Korea
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• 제18권6호
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• pp.746-752
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• 2014

In a multi-camera measurement system, the determination of the external parameters is one of the vital tasks, referred to as the calibration of the system. In this paper, a new geometrical calibration method, which is based on the theory of the vanishing line, is proposed. Using a planar target with three equally spaced parallel lines, the normal vector of the target plane can be confirmed easily in every camera coordinate system of the measurement system. By moving the target into more than two different positions, the rotation matrix can be determined from related theory, i.e., the expression of the same vector in different coordinate systems. Moreover, the translation matrix can be derived from the known distance between the adjacent parallel lines. In this paper, the main factors effecting the calibration are analyzed. Simulations show that the proposed method achieves robustness and accuracy. Experimental results show that the calibration can reach 1.25 mm with the range about 0.5m. Furthermore, this calibration method also can be used for auto-calibration of the multi-camera mefasurement system as the feature of parallels exists widely.

• 제어로봇시스템학회논문지
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• 제14권8호
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• pp.767-773
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• 2008

This paper presents a localization system based on the use of electric compass and tracking IR light source. Digital RGB(Red, Green, Blue)signal of digital CMOS Camera is sent to CPLD which converts the color image to binary image at 30 frames per second. CMOS camera has IR filter and UV filter in front of CMOS cell. The filters cut off above 720nm light source. Binary output data of CPLD is sent to DSP that rapidly tracks the IR light source by moving Camera tilt DC motor. At a robot toward north, electric compass signals and IR light source angles which are used for calculating the data of the location system. Because geomagnetic field is linear in local position, this location system is possible. Finally, it is shown that position error is within ${\pm}1.3cm$ in this system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.110-112
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• 2005

In this paper, an improved AE (auto exposure) system for digital still camera is proposed. The AE system is the most important part in camera to get high quality picture image. However, there is no remarkable progress in this field until this time in spite of its importance. In recent, some researchers try to develop an AE system with signal processing technique. But it has some problems in exposure time and sometimes generates oscillation in brightness. Therefore, we develop a new system using a control technology to remove such phenomena. This new system shows about 30% improved performance than conventional one.

• 제어로봇시스템학회논문지
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• 제6권5호
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• pp.383-389
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• 2000

This paper presents a stereo camera system that provides a Pair of stereo images using a Biprism. The equivalent of a stereo Pair of images is formed as the left and right halves of a single CCD image. The system is therefore cheap and extremely easy to calibrate since it requires only one CCD camera. An additional advantage of the geometrical set-up is that corresponding features lie on the same scanline automatically, The single camera and Biprism have led to a simple stereo system for which correspondence is very easy and which is accurate for nearby objects in a small field of view. Since we use only a single lens, calibration of the system is greatly simplified. Given the parameters in the Biprism-stereo camera system, we can reconstruct the 3-D structure using only the disparity between the corresponding points.

• 대한전기학회논문지:시스템및제어부문D
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• 제49권5호
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• pp.235-240
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• 2000

A low cost lighting system for line-scan cameras has been developed with 3-phase power. When exposure time of line-scan camera is shorter than fluctuation period of illumination, the average gray value of each acquired 1-D image varies. Detecting defects on the objects's surface under such illuminating environment is very difficult. The proposed lighting system is composed of low-cost fluorescent lights based on 3-phase power. The specially designed lighting pack and the properly selected lighting position enable to get the rippleless lighting. The principle of the proposed lighting system has been explained analytically. The lighting system has been tested for fabric inspection with line-scan camera and it's efficacy has been proved.