• 제목/요약/키워드: Camera Variation

검색결과 299건 처리시간 0.023초

DMC 카메라의 블록기하 안정성 분석 (Stability Analysis of DMC's Block Geometry)

  • 이재원;이동민
    • 대한토목학회논문집
    • /
    • 제29권6D호
    • /
    • pp.771-779
    • /
    • 2009
  • GIS의 자료기반이 되는 수치지도는 주로 재래식 항공사진측량에 의해서 제작되고 있다. 따라서 촬영된 아날로그 항공사진은 필름의 현상, 인화, 스캐닝 작업 과정을 거쳐 수치지도 제작에 이용되고 있다. 하지만 디지털 항측카메라의 개발로 촬영된 사진의 전처리과정 없이 직접 디지털 영상의 획득이 가능하여 항공사진의 효율성이 극대화 되고 있는 실정이다. 본 연구 에서는 면형방식 카메라인 DMC(Digital Modular Camera) 영상의 블록구성에 따른 기하적 안정성을 검증하기 위하여 횡스트립의 유무, GPS/INS 외부표정요소의 유무 및 지상기준점 수를 달리한 조건으로 블록조정을 수행하였다. 각 조건별 블록조정의 결과로 부터 외부표정요소에 대한 잔차의 변화를 계산하여 정확도를 상호 비교하였다. 연구 결과 횡스트립 추가 시 블록은 기하학적으로 약 30% 안정함을 알 수 있었고, 외부표정요소에서는 횡스트립 추가 시 표준편차의 평균에서 X축으로 2cm, Y축으로 3cm, Z축으로 3cm 더 우수하였으며, omega는 6", phi는 4", kappa는 3" 더 우수하게 나타났다.

신경망 기반 차량 이미지센서 시스템을 위한 플리커 프리 공간-PSK 변조 기법 (Flicker-Free Spatial-PSK Modulation for Vehicular Image-Sensor Systems Based on Neural Networks)

  • Nguyen, Trang;Hong, Chang Hyun;Islam, Amirul;Le, Nam Tuan;Jang, Yeong Min
    • 한국통신학회논문지
    • /
    • 제41권8호
    • /
    • pp.843-850
    • /
    • 2016
  • This paper introduces a novel modulation scheme for vehicular communication in taking advantage of existing LED lights available on a car. Our proposed 2-Phase Shift Keying (2-PSK) is a spatial modulation approach in which a pair of LED light sources in a car (either rear LEDs or front LEDs) is used as a transmitter. A typical camera (i.e. low frame rate at no greater than 30fps) that either a global shutter camera or a rolling shutter camera can be used as a receiver. The modulation scheme is a part of our Image Sensor Communication proposal submitted to IEEE 802.15.7r1 (TG7r1) recently. Also, a neural network approach is applied to improve the performance of LEDs detection and decoding under the noisy situation. Later, some analysis and experiment results are presented to indicate the performance of our system

ccd 카메라를 이용한 금속 용융면의 온도분포측정 (Measurement of temperature profile in molter metal using a cod camera)

  • 노시표;정의창;임창환;김철중
    • 한국진공학회지
    • /
    • 제12권1호
    • /
    • pp.64-69
    • /
    • 2003
  • 원자력산업용 소재로 사용되는 가돌로니엄 (Gd, 원자번호 64) 금속을 20 kW 내외의 고출력 전자빔을 이용하여 용융시키고, 그 용융면의 온도 분포를 측정하였다 광학 필터들과 렌즈구경 크기를 조절하여 용융면에서 발생하는 방사강도를 ccd 카메라로 받아들이고 실시간으로 컴퓨터에 저장하였다. 이 방법을 이용하여 전자빔의 출력에 따른 용융면의 크기를 실시간으로 모니터 할 수 있어 안정적인 전자빔의 동작이 가능하였다 그리고 가돌로니엄 금속 용융면을 흑체복사로 가정하고 Planck's law를 적용한 결과는 적외선 온도계로 측정한 결과보다 동일한 전자빔 출력에서 100~$200^{\circ}C$ 높은 값을 보였다.

Moving Object Detection Using Sparse Approximation and Sparse Coding Migration

  • Li, Shufang;Hu, Zhengping;Zhao, Mengyao
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제14권5호
    • /
    • pp.2141-2155
    • /
    • 2020
  • In order to meet the requirements of background change, illumination variation, moving shadow interference and high accuracy in object detection of moving camera, and strive for real-time and high efficiency, this paper presents an object detection algorithm based on sparse approximation recursion and sparse coding migration in subspace. First, low-rank sparse decomposition is used to reduce the dimension of the data. Combining with dictionary sparse representation, the computational model is established by the recursive formula of sparse approximation with the video sequences taken as subspace sets. And the moving object is calculated by the background difference method, which effectively reduces the computational complexity and running time. According to the idea of sparse coding migration, the above operations are carried out in the down-sampling space to further reduce the requirements of computational complexity and memory storage, and this will be adapt to multi-scale target objects and overcome the impact of large anomaly areas. Finally, experiments are carried out on VDAO datasets containing 59 sets of videos. The experimental results show that the algorithm can detect moving object effectively in the moving camera with uniform speed, not only in terms of low computational complexity but also in terms of low storage requirements, so that our proposed algorithm is suitable for detection systems with high real-time requirements.

입술 움직임 정보를 이용한 실시간 화자 클로즈업 시스템 구현 (Real Time Speaker Close-Up System using The Lip Motion Informations)

  • 권혁봉;장언동;윤태승;안재형
    • 한국멀티미디어학회논문지
    • /
    • 제4권6호
    • /
    • pp.510-517
    • /
    • 2001
  • 본 논문에서는 다수의 사람이 존재하는 입력영상에서 입술 움직임 정보를 이용한 실시간 화자 클로즈업(close-up) 시스템을 구현한다. 칼라 CCD 카메라를 통해 입력되는 동영상에서 화자를 검출한 후 입술 움직임 정보를 이용하여 다른 한 대의 카메라로 화자를 클로즈업한다. 구현된 시스템은 얼굴색 정보와 형태 정보를 이용하여 각 사람의 얼굴 및 입술 영역을 검출한 후, 입술 영역 변화량을 이용하여 화자를 검출한다. 검출된 화자를 클로즈업하기 위하여 PTZ(Pan/Tilt/Zoom) 카메라를 사용하였으며, RS-232C 시리얼 포트를 이용하여 카메라를 제어한다. 실험결과 3인 이상의 입력 동영상에서 정확하게 화자를 검출할 수 있다.

  • PDF

Median modified wiener filter for improving the image quality of gamma camera images

  • Park, Chan Rok;Kang, Seong-Hyeon;Lee, Youngjin
    • Nuclear Engineering and Technology
    • /
    • 제52권10호
    • /
    • pp.2328-2333
    • /
    • 2020
  • The filter technique was applied to noise images, as noise is the significant factor that cause poor image quality due to lower photon counting. The purpose of this study is to confirm that image quality can be improved using the median modified Wiener filter (MMWF) technique; this is achieved via a National Electrical Manufacturers Association International Electrotechnical Commission body phantom with four large spheres that are filled with the 99mTc radioisotope when evaluating the image quality. Conventional filters such as Wiener, Gaussian, and median filters were designed, and signal to noise ratio, coefficient of variation, and contrast to noise ratio were used as the evaluation parameters. The improvement in the image quality was in the following order, from the least to the highest improvement, in all cases: Wiener filter, Gaussian filter, median filter, and the MMWF technique. The results show that the image quality was improved from 20.6 to 65.5%, 7.4-40.3%, and 12.7-44.7% for the SNR, COV, and CNR values, respectively, when using the MMWF technique, compared with the use of conventional filters. In conclusion, our results demonstrated that the MMWF technique is useful for reducing the noise distribution in gamma camera images.

열화상 카메라를 이용한 검도 동작의 온도 특성 분석 기초 연구 (A Basic Study on Temperature Characteristic Analysis of Kumdo Motion by Infrared Rays Camera)

  • 이규선;남중웅;석강훈;김정배
    • 융복합기술연구소 논문집
    • /
    • 제2권1호
    • /
    • pp.18-23
    • /
    • 2012
  • The purpose of this study is to visually confirm on variation of temperature changes according to the basic of Kumdo by using infrared rays camera and to obtain the difference of temperature distribution according to the warm up procedure. We selected randomly two Kumdo players, and recorded twice continuously their actions of three basic(Head Hitting, Wrist Hitting, Waist Hitting) motions of Kumdo. In other to obtain the effect of warm up procedure, we recorded again their actions including warm-up motions. Four measuring points on the body were selected in each motion considering the error on continuous recoding. Temperature distributions of the before and after warming up procedure were analyzed at two measuring point. Skin temperature distributions of the players's body in two cases are shown a similar tendency. It can be predicted that the parts of large physical movement result in the large changes of temperature according to the warm up motion.

  • PDF

열화상 카메라를 이용한 택견 동작의 온도 특성 분석 기초 연구 (A Basic Study on Temperature Characteristic Analysis of Taekgyeon Motion by Infrared Rays Camera)

  • 이규선;남중웅;석강훈;김정배
    • 융복합기술연구소 논문집
    • /
    • 제2권1호
    • /
    • pp.31-37
    • /
    • 2012
  • The purpose of this study is to visually confirm on variation of temperature changes according to the basic of Taekgyoen by using infrared rays camera and to obtain difference of temperature distribution according to the warm up procedure. We selected randomly two Taekgyeon players, and recorded twice continuously their actions of three basic motions of Taekgyeon. In other to obtain effect of warm up procedure, we recorded again their actions including warm-up motions. Four measuring points on the body were selected in each motion considering the error on continuous recoding. Temperature distributions of the before and after warming up procedure were analyzed at two measuring point. Temperature distributions of skin of players body in two cases are shown a similar tendency. It can be predicted that the parts of large physical movement result in the large changes of temperature according to the warm up motion.

  • PDF

머신 비전 라인 스캔 카메라를 위한 라인 스캔 광원의 제어 특성에 관한 연구 (A Study on the Control Characteristics of Line Scan Light Source for Machine Vision Line Scan Camera)

  • 김태화;이천
    • 한국전기전자재료학회논문지
    • /
    • 제34권5호
    • /
    • pp.371-381
    • /
    • 2021
  • A machine vision inspection system consists of a camera, optics, illumination, and image acquisition system. Especially a scanning system has to be made to measure a large inspection area. Therefore, a machine vision line scan camera needs a line scan light source. A line scan light source should have a high light intensity and a uniform intensity distribution. In this paper, an offset calibration and slope calibration methods are introduced to obtain a uniform light intensity profile. Offset calibration method is to remove the deviation of light intensity among channels through adding intensity difference. Slope calibration is to remove variation of light intensity slope according to the control step among channels through multiplying slope difference. We can obtain an improved light intensity profile through applying offset and slope calibration simultaneously. The proposed method can help to obtain clearer image with a high precision in a machine vision inspection system.

충돌 부탄 화염의 분석을 위한 복합 광학 계측 기법 개발 (Development of Combined Optical System for Analysis of Impinging Butane Flame)

  • 백승환;안성수;고한서
    • 한국가시화정보학회:학술대회논문집
    • /
    • 한국가시화정보학회 2005년도 추계학술대회 논문집
    • /
    • pp.69-73
    • /
    • 2005
  • Three-dimensional density distributions of an impinging and eccentric flame have been analyzed numerically and experimentally by a combined optical system with a digital speckle tomography. The flame has been ignited by premixed butane/air from air holes and impinged vertically against a plate located at the upper side of tile burner nozzle. In order to compare with experimental data, computer synthesized phantoms of impinging and eccentric flames have been made and reconstructed by a developed three-dimensional multiplicative algebraic reconstruction technique (MART). A new scanning technique has been developed for the analysis of speckle displacements to investigate wall jet regions of the impinging flame including sharp variation of the flow direction and pressure gradient. The reconstructed temperatures have been compared with a temperature photography by an infrared camera and results of numerical analysis using a finite-element method.

  • PDF