• 제목/요약/키워드: imaging processing

검색결과 1,001건 처리시간 0.03초

육각형 렌즈 어레이로부터 요소영상을 생성하기 위한 병렬 처리 기법 (Parallel Processing Method for Generating Elemental Images from Hexagonal Lens Array)

  • 김도형;박찬;정지성;권기철;김남;류관희
    • 한국콘텐츠학회논문지
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    • 제12권6호
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    • pp.1-8
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    • 2012
  • 대부분 집적영상 기법에서는 사각형 렌즈 어레이가 사용되고 있으며, 이로 인해 집적된 빛의 분포는 사각격자 형태로 기록된다. 그러나 육각형 렌즈 어레이를 사용하면, 사각형 렌즈 어레이보다 더 높은 밀도의 빛의 분포와 이상적인 원형 렌즈에 가깝게 이미지를 기록 또는 재생 할 수 있다[4]. 육각형 렌즈 어레이 요소영상을 병렬 처리 기법을 사용하여 생성하기 위해서는 요소영상을 구성하는 각 화소에 대하여 그 화소가 속할 육각형 렌즈를 결정해야하고, 이 과정은 화면에 출력되는 모든 화소에 대하여 진행 되며 많은 계산량이 요구된다. 본 논문에서는 3D 볼륨 데이터를 사용하여 육각형 렌즈 어레이에 대한 요소영상을 생성하기 위해 OpenCL를 사용한 병렬 처리 기법을 제안한다. 제안 된 방법을 위한 실험에는 Male [$128{\times}256{\times}256$화소] 볼륨데이터를 사용하였으며, 실험 결과 $20{\times}20$개의 육각형 렌즈 어레이에 대해 요소영상을 초당 20~60장 생성할 수 있었다.

A New 3D Active Camera System for Robust Face Recognition by Correcting Pose Variation

  • Kim, Young-Ouk;Jang, Sung-Ho;Park, Chang-Woo;Sung, Ha-Gyeong;Kwon, Oh-Yun;Paik, Joon-Ki
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.1485-1490
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    • 2004
  • Recently, we have remarkable developments in intelligent robot systems. The remarkable features of intelligent robot are that it can track user, does face recognition and vital for many surveillance based systems. Advantage of face recognition when compared with other biometrics recognition is that coerciveness and contact that usually exist when we acquire characteristics do not exist in face recognition. However, the accuracy of face recognition is lower than other biometric recognition due to decrease in dimension from of image acquisition step and various changes associated with face pose and background. Factors that deteriorate performance of face recognition are many such as distance from camera to face, lighting change, pose change, and change of facial expression. In this paper, we implement a new 3D active camera system to prevent various pose variation that influence face recognition performance and propose face recognition algorithm for intelligent surveillance system and mobile robot system.

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Guidelines for Cardiovascular Magnetic Resonance Imaging from the Korean Society of Cardiovascular Imaging (KOSCI) - Part 3: Perfusion, Delayed Enhancement, and T1- and T2 Mapping

  • Im, Dong Jin;Hong, Su Jin;Park, Eun-Ah;Kim, Eun Young;Jo, Yeseul;Kim, Jeong Jae;Park, Chul Hwan;Yong, Hwan Seok;Lee, Jae Wook;Hur, Jee Hye;Yang, Dong Hyun;Lee, Bae-Young
    • Investigative Magnetic Resonance Imaging
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    • 제24권1호
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    • pp.1-20
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    • 2020
  • This document is the third part of the guidelines for the interpretation and post-processing of cardiac magnetic resonance (CMR) studies. These consensus recommendations have been developed by a Consensus Committee of the Korean Society of Cardiovascular Imaging (KOSCI) to standardize the requirements for image interpretation and post-processing of CMR. This third part of the recommendations describes tissue characterization modules, including perfusion, late gadolinium enhancement, and T1- and T2 mapping. Additionally, this document provides guidance for visual and quantitative assessment, consisting of "What-to-See," "How-To," and common pitfalls for the analysis of each module. The Consensus Committee hopes that this document will contribute to the standardization of image interpretation and post-processing of CMR studies.

Restoration of Chest X-ray by Kalman Filter

  • Kim, Jin-Woo
    • Journal of information and communication convergence engineering
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    • 제8권5호
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    • pp.581-585
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    • 2010
  • A grid was sandwiched between two cascaded imaging plates. Using a fan-beam X-ray tube and a single exposure scheme, the two imaging plates, respectively, recorded grid-less and grid type information of the object. Referring to the mathematical model of the Grid-less and grid technique, it was explained that the collected components whereas that of imaging plates with grid was of high together with large scattered components whereas that of imaging plate with grid was of low and suppressed scattered components. Based on this assumption and using a Gaussian convolution kernel representing the effect of scattering, the related data of the imaging plates were simulated by computer. These observed data were then employed in the developed post-processing estimation and restoration (kalman-filter) algorithms and accordingly, the quality of the resultant image was effectively improved.

Pyramid Edge Detection과 Line Fitting을 이용한 퓨리에 기반의 영상정합 (Fourier Based Image Registration Using Pyramid Edge Detection and Line Fitting)

  • 김기백;김종수;최종수
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2008년도 하계종합학술대회
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    • pp.999-1000
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    • 2008
  • Image Registration is used many works in image processing widely. But It is difficult to find the accuracy informations such as translation, rotation, and scaling between images. This paper proposes an algorithm that Fourier based image registration using the pyramid edge detection and line fitting. It can be estimated the informations by each sub-pixels. The proposed algorithm can be used for image registrations which high efficiency is required such as GIS, or MRI, CT, image mosaicing, weather forecasting, etc.

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레이저 가공에 의한 백라이트 도광판 성능 향상 (Improvement of Light Guide Panel Performance by Laser Patterning)

  • 김영섭;김태훈;박소희;최영희;최은서;신용진
    • 한국레이저가공학회지
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    • 제10권1호
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    • pp.29-34
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    • 2007
  • We propose a novel application of laser engraving to patterning of light guide panel (LGP) for backlight. The feasibility of three-dimensional engraved pattern in the LGP was verified by measuring brightness and uniformity. To improve the overall uniformity, we have modified proposed patterns and found improved design for patterns. The tailoring of pattern by using laser engraving method could endow the controllability of uniformity. The proposed LGPs are more efficient in both average brightness and uniformity of illumination than the conventional LGPs which have surface pattern on the panel.

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Application of a deep learning algorithm to Compton imaging of radioactive point sources with a single planar CdTe pixelated detector

  • Daniel, G.;Gutierrez, Y.;Limousin, O.
    • Nuclear Engineering and Technology
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    • 제54권5호
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    • pp.1747-1753
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    • 2022
  • Compton imaging is the main method for locating radioactive hot spots emitting high-energy gamma-ray photons. In particular, this imaging method is crucial when the photon energy is too high for coded-mask aperture imaging methods to be effective or when a large field of view is required. Reconstruction of the photon source requires advanced Compton event processing algorithms to determine the exact position of the source. In this study, we introduce a novel method based on a Deep Learning algorithm with a Convolutional Neural Network (CNN) to perform Compton imaging. This algorithm is trained on simulated data and tested on real data acquired with Caliste, a single planar CdTe pixelated detector. We show that performance in terms of source location accuracy is equivalent to state-of-the-art algorithms, while computation time is significantly reduced and sensitivity is improved by a factor of ~5 in the Caliste configuration.

초점면 배열 방식의 열상카메라 시스템의 구현 (Implementation of a Thermal Imaging System with Focal Plane Array Typed Sensor)

  • 박세화;원동혁;오세중;윤대섭
    • 제어로봇시스템학회논문지
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    • 제6권5호
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    • pp.396-403
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    • 2000
  • A thermal imaging system is implemented for the measurement and the analysis of the thermal distribution of the target objects. The main part of the system is a thermal camera in which a focal plane array typed sensor is introduced. The sensor detects the mid-range infrared spectrum of target objects and then it outputs a generic video signal which should be processed to form a frame thermal image. Here, a digital signal processor(DSP) is applied for the high speed processing of the sensor signals. The DSP controls analog-to-digital converter, performs correction algorithms and outputs the frame thermal data to frame buffers. With the frame buffers can be generated a NTSC signal and transferred the frame data to personal computer(PC) for the analysis and a monitoring of the thermal scenes. By performing the signal processing functions in the DSP the overall system achieves a simple configuration. Several experimental results indicate the performance of the overall system.

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TV 영상 신호에서의 Constant Luminance 효과에 관한 연구 (A Study on the Influence of Constant Luminance on TV Signal)

  • 김진서;강병호;조맹섭
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2001년도 추계학술발표논문집 (상)
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    • pp.707-710
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    • 2001
  • TV 시스템이 발명된 이후 현재까지 사용되어 온 영상 신호의 생성, 전송 및 재생 방법은 HDTV, 디지털 시네마 등 영상 시스템의 획기적인 발전과 더불어, 보다 고선명, 고화질의 영상 재생이 요구된다. 본 논문에서는 기존의 TV 시스템에서의 영상재생 결과와, constant luminance 방법에 의한 영상 재생 결과를 관찰자 평가 실험을 통해 비교 분석한 데이터를 제시한다.

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동영상 화질 개선을 위한 Constant Luminance 적용에 관한 연구 (A Study on Applying Constant Luminance for Quality Enhancement of Moving Images)

  • 김진서;강병호;조맹섭
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2002년도 추계학술발표논문집 (상)
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    • pp.735-738
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    • 2002
  • 휘도 신호만을 이용한 흑백 TV 에서부터 오늘날의 디지털 HDTV 에 이르기까지의 TV 시스템에서 사용되어 온 영상 신호의 생성, 전송 및 재생 방법은 HDTV, 디지털 시네마 등 영상 시스템의 획기적인 발전과 더불어, 보다 고선명, 고화질을 요구하게 되었다. 본 논문에서는 기존의 TV 시스템에서의 영상재생 결과와, constant luminance방법에 의한 영상 재생 결과를 관찰자 평가 실험을 통해 비교 분석한 데이터를 제시한다.

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