• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.809-813
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• 2004

In this paper, we developed a network camera for CMOS camera module inspection. The design, implementation details including embedded linux porting and CPLD logics, and performance of network camera are described. The network camera consists of SoC(S3C4530A), CPLD and CMOS image sensor. In order to image data of CMOS image sensor we designed capture logics on CPLD by using VHDL program. Embedded Linux such as uClinux is performed on the network camera to utilize development environment and TCP/IP protocol specification. The application is based on socket communication between GUI on PC and Embedded Linux based network camera. When JPEG compression is applied, the transmission speed was improved enough for this system to be used for an alternative of expensive CCTV or remote monitoring system in a power plant and uninhabited places.

• Journal of Multimedia Information System
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• v.5 no.2
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• pp.105-110
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• 2018

Autonomous cars require the integration of multiple communication systems for driving safety. Many carmakers unveil mirrorless concept cars aiming to replace rear and sideview mirrors in vehicles with camera monitoring systems, which eliminate blind spots and reduce risk. This paper presents optical vehicle-to-vehicle (V2V) communications for autonomous mirrorless cars. The flicker-free light emitting diode (LED) light sources, providing illumination and data transmission simultaneously, and a high speed camera are used as transmitters and a receiver in the OCC link, respectively. The rear side vehicle transmits both future action data and vehicle type data using a headlamp or daytime running light, and the front vehicle can receive OCC data from the camera that replaces side mirrors so as not to prevent accidents while driving. Experimental results showed that action and vehicle type information were sent by LED light sources successfully to the front vehicle's camera via the OCC link and proved that OCC-based V2V communications for mirrorless cars can be a viable solution to improve driving safety.

• Journal of Digital Convergence
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• v.12 no.8
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• pp.295-302
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• 2014

Essential to the establishment of such 3D spatial information are the laser scanning technology to obtain high-precision 3D point group data and the photography-metric camera to obtain high-resolution multispectral image information. The photography-metric camera, however, lacks in usability for its broad scope of utilization due to the high purchase price, difficult purchase channel, and low applicability. This study thus set out to investigate a technique to establish multi-dimensional ortho-image data with a single lens reflex digital camera of high speed and easy accessibility for general users. That is, the study remodeled a single lens reflex digital camera and calibrated the remodeled camera to establish 3D multispectral image information, which is the essential data of 3D spatial information. Multi-dimensional ortho-image data were collected by surveying the reference points for stereo photos, taking multispectral shots of the objects, and converting them into ortho-images.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.4
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• pp.487-493
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• 1998

Camera calibration is the process of determining the coordinate relationship between a camera image and its real world space. Accurate calibration of a camera is necessary for the applications that involve quantitative measurement of camera images. However, if the camera plane is parallel or near parallel to the calibration board on which 2 dimensional objects are defined(this is called "ill-conditioned"), existing solution procedures are not well applied. In this paper, we propose a neural network-based approach to camera calibration for 2D images formed by a mono-camera or a pair of cameras. Multi-layer perceptrons are developed to transform the coordinates of each image point to the world coordinates. The validity of the approach is tested with data points which cover the whole 2D space concerned. Experimental results for both mono-camera and stereo-camera cases indicate that the proposed approach is comparable to Tsai's method［8］. Especially for the stereo camera case, the approach works better than the Tsai's method as the angle between the camera optical axis and the Z-axis increases. Therefore, we believe the approach could be an alternative solution procedure for the ill -conditioned camera calibration.libration.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.233-236
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• 2004

In this study, we analyzed the accuracy of the conversion from DLT parameters to physical camera parameters and optimized the use of DLT model for non-metric cameras in photogrammetric tasks. Using the simulated data, we computed two sets of physical camera parameters from DLT parameters and Bundle adjustment for various cases. Comparing two results based on the RMSE values of check points, we optimized the arrangement of GCPs for DLT.

• The Journal of Korea Robotics Society
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• v.4 no.4
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• pp.305-311
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• 2009

FastSLAM is a factored solution to SLAM problem using a Rao-Blackwellized particle filter. In this paper, we propose a practical FastSLAM implementation method using an infrared camera for indoor environments. The infrared camera is equipped on a Pioneer3 robot and looks upward direction to the ceiling which has infrared tags with the same height. The infrared tags are detected with theinfrared camera as measurements, and the Nearest Neighbor method is used to solve the unknown data association problem. The global map is successfully built and the robot pose is predicted in real time by the FastSLAM2.0 algorithm. The experiment result shows the accuracy and robustness of the proposed method in practical indoor environment.

• Proceedings of the KIEE Conference
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• 2005.07d
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• pp.2821-2823
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• 2005

When we deal with the image data through camera lens, much works are necessary for removing image distortions and obtaining accurate informations from the raw data. However, the calibration process is very complicated and requires many trials and errors. In this paper, 3 new approach to image processing is presented by developing a H/W vision system with a tracking camera. Using motor control with encoders the proposed tracking method tells us exact displacements of a moving object. Therefore this method does not require any calibration process for pin cusion. Owing to the mobility one camera covers wide ranges and, by lowering its height, the camera also obtains high resolution of the image. We first introduce the structure of the motion analysis system. Then the construced vision system is investigated by some experiments.

• Proceedings of the KIEE Conference
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• 2005.05a
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• pp.255-257
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• 2005

This paper describes a method for obstacle avoidance and map building for mobile robots using one CCD camera. The captured image from one camera has the feature that some parts where focused look fine but the other parts look blear (this is the out-focusing effect). Using this feature a mobile robot can find obstacles in his way from the captured image. After Processing the image, a robot can not only determine whether an obstacle is in front of him or not, but also calculate the distance from obstacles based on image data and the focal distance of its camera lens. Finally, robots can avoid the obstacle and build the map using this calculated data.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.101-101
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• 2000

MSC(Multispectral Camera), which will be a unique payload on KOMPSAT-II, is designed to collect panchromatic and multi-spectral imagery with a ground sample distance of 1m and a swath width of 15km at 685km altitude in sun-synchronous orbit. The instrument is designed to have an orbit operation duty cycle of 20% over the mission life time of 3 years. MSC electronics consists of three main subsystems; PMU(Payload Management Unit), CEU(Camera Electronics Unit) and PDTS(Payload Data Transmission Subsystem). PMU performs all the interface between spacecraft and MSC, and manages all the other subsystems by sending commands to them and receiving telemetry from them with software protocol through RS-422 interface. CEU controls FPA(Focal Plane Assembly) which contains TDI(Timc Delay Integration) CCD(Charge Coupled Device) and its clock drivers. PMU provides a Master Clock to synchronize panchromatic and multispectral camera. PDTS performs compression, storage and encryption of image data and transmits them to the ground station through x-band.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.1
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• pp.8-13
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• 2017

Compare with other communication system based RF technology, Optical Camera Communication (OCC) has limitation on data rate due to the low frame rate of camera. The limitation on data rate can be solved with multiple-input and multiple-output (MIMO) technology; and it is the final target of all researches on OCC. The MIMO topology can be implemented easily without breaking out the architecture of image sensor. For image sensor classification, there are two architectures have been developed: rolling shutter and global shutter. The operation of two techniques is different so the performance is also different. In this paper we analyze and evaluate the performance of the MIMO architecture for OCC.