• Title/Summary/Keyword: Background illumination

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The Effect of Background Grey Levels on the Visual Perception of Displayed Image on CRT Monitor (CRT 모니터의 배경(背景) 계조도(階調度)가 영상의 시각인식(視覺認識)에 미치는 영향)

  • Kim, Jong-Hyo;Park, Kwang-Suk;Min, Byoung-Goo;Lee, Choong-Woong
    • Proceedings of the KOSOMBE Conference
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    • v.1991 no.05
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    • pp.18-21
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    • 1991
  • In this paper, the effect of background grey levels on the visual perception of target image displayed on CRT monitor has been investigated. The purpose of this study is to investigate the efficacy of CRT monitor as a display medium of image information especially in medical imaging field. Three sets of experiments have been performed in this study; the first was to measure the luminance response of CRT monitor and to find the best fitting equation, and the second was the psychophysical experiment measuring the threshold grey level difference between the target image and the background required for visual discrimination for various background grey levels, and the third was to develop a visual model that is predictable of the threshold grey level difference measured in the psychophysical experiment. The result of psycophysical experiment shows that the visual perception performance is significantly degraded in the range of grey levels lower than 50, which is turned out due to the low luminance change of CRT monitor in this range while human eye has been adapted to relatively bright ambient illumination.

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Implementation of a Robust Visual Surveillance Algorithm under outdoor environment (옥외 환경에강인한 영상 감시알고리듬구현)

  • Jung, Yong-Bae;Kim, Tea-Hyo
    • Journal of the Institute of Convergence Signal Processing
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    • v.10 no.2
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    • pp.112-119
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    • 2009
  • This paper describes a robust visual surveillance algorithm under outdoor environment. One of the difficult problems for outdoor is to obtain effective updating process of background images. Because background images generally contain the shadows of buildings, trees, moving clouds and other objects, they are changed by lapse of time and variation of illumination. They provide the lowering of performance for surveillance system under outdoor. In this paper, a robust algorithm for visual surveillance system under outdoor is proposed, which apply the mixture Gaussian filter and color invariant property on pixel level to update background images. In results, it was showed that the moving objects can be detected on various shadows under outdoor.

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Codebook-Based Foreground Extraction Algorithm with Continuous Learning of Background (연속적인 배경 모델 학습을 이용한 코드북 기반의 전경 추출 알고리즘)

  • Jung, Jae-Young
    • Journal of Digital Contents Society
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    • v.15 no.4
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    • pp.449-455
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    • 2014
  • Detection of moving objects is a fundamental task in most of the computer vision applications, such as video surveillance, activity recognition and human motion analysis. This is a difficult task due to many challenges in realistic scenarios which include irregular motion in background, illumination changes, objects cast shadows, changes in scene geometry and noise, etc. In this paper, we propose an foreground extraction algorithm based on codebook, a database of information about background pixel obtained from input image sequence. Initially, we suppose a first frame as a background image and calculate difference between next input image and it to detect moving objects. The resulting difference image may contain noises as well as pure moving objects. Second, we investigate a codebook with color and brightness of a foreground pixel in the difference image. If it is matched, it is decided as a fault detected pixel and deleted from foreground. Finally, a background image is updated to process next input frame iteratively. Some pixels are estimated by input image if they are detected as background pixels. The others are duplicated from the previous background image. We apply out algorithm to PETS2009 data and compare the results with those of GMM and standard codebook algorithms.

An Improved Adaptive Background Mixture Model for Real-time Object Tracking based on Background Subtraction (배경 분리 기반의 실시간 객체 추적을 위한 개선된 적응적 배경 혼합 모델)

  • Kim Young-Ju
    • Journal of the Korea Society of Computer and Information
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    • v.10 no.6 s.38
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    • pp.187-194
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    • 2005
  • The background subtraction method is mainly used for the real-time extraction and tracking of moving objects from image sequences. In the outdoor environment, there are many changeable environment factors such as gradually changing illumination, swaying trees and suddenly moving objects , which are to be considered for an adaptive processing. Normally, GMM(Gaussian Mixture Model) is used to subtract the background by considering adaptively the various changes in the scenes, and the adaptive GMMs improving the real-time Performance were Proposed and worked. This paper, for on-line background subtraction, employed the improved adaptive GMM, which uses the small constant for learning rate a and is not able to speedily adapt the suddenly movement of objects, So, this paper Proposed and evaluated the dynamic control method of a using the adaptive selection of the number of component distributions and the global variances of pixel values.

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Fabrication of 3D Feed Horn IR Antenna for IR Detector

  • Kim, Kun-Tae;Han, Yong-Hee;Shin, Hyun-Joon;Sung Moon;Park, Jung-Ho
    • KIEE International Transactions on Electrophysics and Applications
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    • v.4C no.4
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    • pp.170-175
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    • 2004
  • A three dimensional feed horn 10${\mu}{\textrm}{m}$ wavelength infrared antenna has been suggested, fabricated and characterized. It was applied to an infrared detector for efficient collecting of IR radiation and for reducing background noise. The horn antenna size was designed for maximum antenna directivity. The 3D feed horn antenna mold was fabricated using rotating and tilted illumination while the antenna plate was constructed by way of electroplating. Antenna characteristics were measured by coupling with a microbolometer. Measurement results indicated that the directivity of the antenna is 16.1㏈ and the background noise is reduced by approximately two times.

Implementation of Drowsiness Driving Warning System based on Improved Eyes Detection and Pupil Tracking Using Facial Feature Information (얼굴 특징 정보를 이용한 향상된 눈동자 추적을 통한 졸음운전 경보 시스템 구현)

  • Jeong, Do Yeong;Hong, KiCheon
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.5 no.2
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    • pp.167-176
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    • 2009
  • In this paper, a system that detects driver's drowsiness has been implemented based on the automatic extraction and the tracking of pupils. The research also focuses on the compensation of illumination and reduction of background noises that naturally exist in the driving condition. The system, that is based on the principle of Haar-like feature, automatically collects data from areas of driver's face and eyes among the complex background. Then, it makes decision of driver's drowsiness by using recognition of characteristics of pupils area, detection of pupils, and their movements. The implemented system has been evaluated and verified the practical uses for the prevention of driver's drowsiness.

Fire Detection in Outdoor Using Statistical Characteristics of Smoke (연기의 통계적 특성을 이용한 실외 화재 감지)

  • Kim, Hyun-Tae;Park, Jang-Sik
    • The Journal of the Korea institute of electronic communication sciences
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    • v.9 no.2
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    • pp.149-154
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    • 2014
  • Detection performance of fire detection in the outdoor depends on weather conditions, the shadow by the movement of the sun, or illumination changes. In this paper, a smoke detection in conjunction with a robust background estimate algorithm to environment change in the outdoor in daytime is proposed. Gaussian Mixture Model (GMM) is applied as background estimation, and also, statistical characteristics of smoke is applied to detect the smoke for separated candidate region. Through the experiments with input videos obtained from a various weather conditions, the proposed algorithms were useful to detect smoke in the outdoor.

A Practical Study on Aids to Navigation (항로표지에 관한 실무적 고찰)

  • Yoon, Byoung-Won
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2007.12a
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    • pp.365-372
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    • 2007
  • The function of navigational aids are to be coincided with the development of navigational equipment and increase of traffics on the sea fairway. Supplementary function or side effect of wharf-edge illumination would be effective to indicate fairway indirectly and collision avoidance between ships and bridge against background light in port area at night also a serious-view light on the bridge posts would be effective to ensure the drifting ships by wind and current force adjacent bridge area.

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Face seqmentation using automatic searching algorithm of thresholding value and statistical projection analysis (자동 임계점 탐색 알고리즘과 통계적 투영 분석을 이용한 얼굴 분할)

  • 김장원;이흥복;김창석
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.8
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    • pp.1874-1884
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    • 1996
  • In this paper, we proposed automatic searching algorithm of thresholding value using multilevel thresholding for face segmentation from input bust image effectively. The proposed algorithm extracted the thresholding value of brightness that is formed background region, face region and hair region without illumination, background and face size from input image. The statistical projection analysis project the brightness of multilevel thresholding image into horizontal and vertical direction and decide the thresholding value of face. And the algorithm extracted elliptical type block of face from input image in order to reduce the back ground region and hair region efficiently. The proposed algorithm can reduce searching area of feature extraction and processing time for face recognication.

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A Study on a effective Information Compressor Algorithm for the variable environment variation using the Kalman Filter

  • Choi, Jae-Yun
    • Journal of the Korea Society of Computer and Information
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    • v.23 no.4
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    • pp.65-70
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    • 2018
  • This paper describes a effective information compressor algorithm for the fourth industrial technology. One of the difficult problems for outdoor is to obtain effective updating process of background images. Because input images generally contain the shadows of buildings, trees, moving clouds and other objects, they are changed by lapse of time and variation of illumination. They provide the lowering of performance for surveillance system under outdoor. In this paper, a effective information algorithm for variable environment variable under outdoor is proposed, which apply the Kalman Estimation Modeling and adaptive threshold on pixel level to separate foreground and background images from current input image. In results, the better SNR of about 3dB~5dB and about 10%~25% noise distribution rate in the proposed method. Furthermore, it was showed that the moving objects can be detected on various shadows under outdoor and better result Information.