• Title/Summary/Keyword: CCD image sensor

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High Fidelity Color Capturing of CCD-Camera System by Using of Spectral Sensitivity Model (스펙트럼 특성 모델을 이용한 CCD카메라 시스템의 고성능 칼라 Capturing)

  • 이상진;신윤철;김일도;김문철
    • Proceedings of the IEEK Conference
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    • 2003.07e
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    • pp.1751-1754
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    • 2003
  • CCD Camera System으로 capture 한 image를 표준 display장치로 재현할 때 capture 할 당시의 원 피사체의 모습을 그대로 재현하여야만 한다. 그러나 일반 consumer 용 camera system의 CCD channel spectral sensitivity 특성이 인간의 spectral sensitivity(1(λ), m(λ), 5(λ)) 특성과 일치하지 않고, linear transform의 관계도 성립하지 않음으로써 capturing시 근본적인 color error가 발생하게 된다. 기존의 CCD Camera System 에서는 CCD sensor 의 color 정보와 display 장치의 color 정보와의 단순한 산술적인 관계로 color를 재구성하는 방법을 사용하고 있어 원 피사체의 color 를 그대로 재현할 수가 없다. 본 논문에서 제시하는 알고리즘은 CCD 의 channel spectral sensitivity특성 과 CIE-color matching function과의 관계를 고려하여 color를 재구성함으로써 color error를 줄이도록 하였다 제시된 알고리즘의 color error를 검증하기 위하여 물체의 고유반사율을 알고 있는 AGFA IT8.7-2 test chart(283 spectra), Dupont Paint Chips(120 spectra), Mcbeth Color Checker(64 spectra) 및 Natural Objects(170 spectra) 등 다양한 objects spectra(637 spectra) [1][2]를 이용하여 기존 방법의 알고리즘과 비교하여 보았다.

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Automatic Building Extraction Using LIDAR and Aerial Image (LIDAR 데이터와 수치항공사진을 이용한 건물 자동추출)

  • Jeong, Jae-Wook;Jang, Hwi-Jeong;Kim, Yu-Seok;Cho, Woo-Sug
    • Journal of Korean Society for Geospatial Information Science
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    • v.13 no.3 s.33
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    • pp.59-67
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    • 2005
  • Building information is primary source in many applications such as mapping, telecommunication, car navigation and virtual city modeling. While aerial CCD images which are captured by passive sensor(digital camera) provide horizontal positioning in high accuracy, it is far difficult to process them in automatic fashion due to their inherent properties such as perspective projection and occlusion. On the other hand, LIDAR system offers 3D information about each surface rapidly and accurately in the form of irregularly distributed point clouds. Contrary to the optical images, it is much difficult to obtain semantic information such as building boundary and object segmentation. Photogrammetry and LIDAR have their own major advantages and drawbacks for reconstructing earth surfaces. The purpose of this investigation is to automatically obtain spatial information of 3D buildings by fusing LIDAR data with aerial CCD image. The experimental results show that most of the complex buildings are efficiently extracted by the proposed method and signalize that fusing LIDAR data and aerial CCD image improves feasibility of the automatic detection and extraction of buildings in automatic fashion.

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Analysis of Sun Tracking Performance of Various Types of Sun Tracking System used in Parabolic Dish Type Solar Thermal Power Plant (접시형 태양열 발전시스템에서 사용하는 여러 가지 형태의 태양추적시스템의 태양추적성능 분석)

  • Seo, Dong-Hyeok;Park, Young-Chil
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.4
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    • pp.388-396
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    • 2011
  • Sun tracking system is the most important subsystem in parabolic dish type solar thermal power plant, since it determines the amount of thermal energy to be collected, thus affects the efficiency of solar thermal power plant most significantly. Various types of sun tracking systems are currently used. Among them, use of photo sensors to located the sun(which is called sensor type) and use of astronomical algorithm to compute the sun position(which is called program type) are two of the mostly used methods. Recently some uses CCD sensor, like CCD camera, which is called image processing type sun tracking system. This work is concerned with the analysis of sun tracking performance of various types of sun tracking systems currently used in the parabolic dish type solar thermal power plant. We first developed a sun tracking error measurement system. Then, we evaluate the performance of five different types of sun tracking systems, sensor type, program type, hybrid type(use of sensor and computed sun position simultaneously), tracking error compensated program type and image processing type. Experimentally obtained data shows that the tracking error compensated program type sun tracking system is very effective and could provide a good sun tracking performance. Also the data obtained shows that the performance of sensor type sun tracking system is being affected by the cloud significantly, while the performance of a program type sun tracking system is being affected by the sun tracking system's mechanical and installation errors very much. Finally image processing type sun tracking system can provide accurate sun tracking performance, but costs more and requires more computational time.

A Study on the Measurement of Spectral Response Characteristics of Color Image Sensor (칼라영상센서의 분광감도 측정에 관한 연구)

  • 박승옥;김홍석
    • Korean Journal of Optics and Photonics
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    • v.6 no.4
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    • pp.266-273
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    • 1995
  • Colors reproduced by color imaging system are affected by various physical factors. The spectral response of the color image sensor is one of the important factors. We developed a spectral response characteristics measurement system which is composed of optical part and color analyzing part. The data from the optical part was analyzed by the color analyzing part and spectral response characteristics of R, G, B three color sensors were obtained. Using this system, the spectral response characteristics of a CCD color camera was measured. From this result, color rendition and linearity of the camera could be analyzed. This measurement system is $.$considered to be very useful for the evaluation of color image sensor characteristics. stics.

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The Obstacle Avoidance and Position Acuracy Control Algorithm for Self Controlled Mobile Robot Using Image Information And Compass Module (영상정보와 방위각 센서를 이용한 장애물 회피와 위치 정밀제어에 대한 알고리즘)

  • 구본민;최중경;박무열;류한성;권정혁;신영호
    • Proceedings of the IEEK Conference
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    • 2002.06e
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    • pp.177-180
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    • 2002
  • In this paper, we has been studied self controlled mobile robot system with CCD camera. This system consists of TMS320F240 digital signal processor, step motor, RF module and CCD camera. 2-axis compass and magnetic sensor, we used wireless RF module for movable command transmiting between robot and host PC. This robot go straight until 95 percent filled screen with white color both side from input image. And the robot recognizes obstacle about 95 percent filled something, so it could turn for avoid the obstacle and conclude new path plan. it could get turning angle from 2-axis compass and magnetic sensor.

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A STUDY ON ENCODING/DECODING TECHNIQUE OF SENSOR DATA FOR A MOBILE MAPPING SYSTEM

  • Bae, Sang-Keun;Kim, Byung-Guk
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.705-708
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    • 2005
  • Mobile Mapping Systems using the vehicle equipped the GPS, IMU, CCD Cameras is the effective system for the management of the road facilities, update of the digital map, and etc. They must provide users with the sensor data which is acquired by Mobile Mapping Systems in real-time so that users can process what they want by using the latest data. But it' s not an easy process because the amount of sensor data is very large, particularly image data to be transmitted. So it is necessary to reduce the amount of image data so that it is transmitted effectively. In this study, the effective method was suggested for the compression/decompression image data using the Wavelet Transformation and Huffman Coding. This technique will be possible to transmit of the geographic information effectively such as position data, attitude data, and image data acquired by Mobile Mapping Systems in the wireless internet environment when data is transmitted in real-time.

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FPGA Design and Realization for Scanning Image Enhancement using LUT Shading Correction Algorithm (LUT 쉐이딩 보정 알고리듬을 이용한 스캐닝 이미지 향상 FPGA 설계 구현)

  • Kim, Young-Bin;Ryu, Conan K.R.
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.8
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    • pp.1759-1764
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    • 2012
  • This paper describes FPGA design and realization using the shading correction algorithm for a CCD scan image enhancement. The shading algorithm is used by LUT (Look-up Table). The image enhancement results from that the histogram minimum value and maximum with respect to all pixels of the CCD image should be extracted, and the shading LUT is constructed to keep constant histogram with offset data. The output of sensor be converted to corrected LUT image in preprocessing, and the converting system is realized by FPGA to be enabled to operate in real time. The result of the experimentation for the proposed system is showed to take the scanning time 2.4ms below. The system is presented to be based on a low speed processor system to scan enhanced images in real time and be guaranteed to be low cost.

Development of a Sensor System for Real-Time Posture Measurement of Mobile Robots (이동 로봇의 실시간 자세 추정을 위한 센서 시스템의 개발)

  • 이상룡;권승만
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.9
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    • pp.2191-2204
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    • 1993
  • A sensor system has been developed to measure the posture(position and orientation) of mobile robots working in industrial environments. The proposed sensor system consists of a CCD camera, retro-reflective landmarks, a strobe unit and an image processing board. The proposed hardware system can be built in economic price compared to commercial vision systems. The system has the capability of measuring the posture of mobile robots within 60 msec when a 386 personal computer is used as the host computer. The experimental results demonstrated a remarkable performance of the proposed sensor system in the posture measurement of mobile robots - the average error in position is less than 3 mm and the average error in orientation is less than 1.5.

A Study on a Visual Sensor System for Weld Seam Tracking in Robotic GMA Welding (GMA 용접로봇용 용접선 시각 추적 시스템에 관한 연구)

  • 김동호;김재웅
    • Journal of Welding and Joining
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    • v.19 no.2
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    • pp.208-214
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    • 2001
  • In this study, we constructed a visual sensor system for weld seam tracking in real time in GMA welding. A sensor part consists of a CCD camera, a band-pass filter, a diode laser system with a cylindrical lens, and a vision board for inter frame process. We used a commercialized robot system which includes a GMA welding machine. To extract the weld seam we used a inter frame process in vision board from that we could remove the noise due to the spatters and fume in the image. Since the image was very reasonable by using the inter frame p개cess, we could use the simplest way to extract the weld seam from the image, such as first differential and central difference method. Also we used a moving average method to the successive position data or weld seam for reducing the data fluctuation. In experiment the developed robot system with visual sensor could be able to track a most popular weld seam. such as a fillet-joint, a V-groove, and a lap-joint of which weld seam include planar and height directional variation.

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Thermal Image Real-time estimation and Fire Alarm by using a CCD Camera (CCD 카메라를 이용한 열화상 실시간 추정과 화재경보)

  • Baek, Dong-Hyun
    • Fire Science and Engineering
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    • v.30 no.6
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    • pp.92-98
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    • 2016
  • This study evaluated thermal image real-time estimation and fire alarm using by a CCD camera, which has been a seamless feature-point analysis method, according to the angle and position and image fusion by a vector coordinate point set-up of equal shape. The system has higher accuracy, fixing data value of temperature sensing and fire image of 0~255, and sensor output-value of 0~5,000. The operation time of a flame specimen within 500 m, 1000 m, and 1500 m from the test report specimen took 7 s, 26 s, and 62 s, respectively, and image creation was proven. A diagnosis of fire accident was designated to 3 steps: Caution/Alarm/Fire. Therefore, a series of process and the transmission of SNS were identified. A light bulb and fluorescent bulb were also tested for a false alarm test, but no false alarm occurred. The possibility that an unwanted alarm will be reduced was verified through a forecast of the fire progress or real-time estimation of a thermal image by the change in the image of a time-based flame and an analysis of the diffusion velocity.