• Title/Summary/Keyword: stereo complex

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Multiview Stereo Matching on Mobile Devices Using Parallel Processing on Embedded GPU (임베디드 GPU에서의 병렬처리를 이용한 모바일 기기에서의 다중뷰 스테레오 정합)

  • Jeon, Yun Bae;Park, In Kyu
    • Journal of Broadcast Engineering
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    • v.24 no.6
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    • pp.1064-1071
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    • 2019
  • Multiview stereo matching algorithm is used to reconstruct 3D shape from a set of 2D images. Conventional multiview stereo algorithms have been implemented on high-performance hardware due to the heavy complexity that contains a large number of calculations in each step. However, as the performance of mobile graphics processors has recently increased rapidly, complex computer vision algorithms can now be implemented on mobile devices like a smartphone and an embedded board. In this paper we parallelize an multiview stereo algorithm using OpenCL on mobile GPU and provide various optimization techniques on the embedded hardware with limited resource.

Target image detection and servo motor control for automatic surveillance tracking (자동 감시 추적을 위한 표적영상 검출 및 서보모터 제어)

  • Shin, Heung Yeoul
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.6 no.2
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    • pp.119-127
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    • 2010
  • In this paper, we propose a new automatic surveillance tracking system that can extract the target from the complex background and foreground noises by using the image-based SAD algorithm and control the servo motor of cameras by using kanatani algorithm. From the experimental results the proposed stereo tracking system is found to track the target adaptively under the circumstance of complex and changing background noises and the possibility of real-time implementation of the proposed system by using the optical system is also suggested.

Development of High-resolution 3-D PIV Algorithm by Cross-correlation (고해상도 3차원 상호상관 PIV 알고리듬 개발)

  • Kim, Mi-Young;Choi, Jang-Woon;Lee, Hyun;Lee, Young-Ho
    • Proceedings of the KSME Conference
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    • 2001.11b
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    • pp.410-416
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    • 2001
  • An algorithm of 3-D particle image velocimetry(3D-PIV) was developed for the measurement of 3-D velocity field of complex flows. The measurement system consists of two or three CCD camera and one RGB image grabber. In this study, stereo photogrammetty was applied for the 3-D matching of tracer particles. Epipolar line was used to decect the stereo pair. 3-D CFD data was used to estimate algorithm. 3-D position data of the first frame and the second frame was used to find velocity vector. Continuity equation was applied to extract error vector. The algorithm result involved error vecotor of about 0.13 %. In Pentium III 450MHz processor, the calculation time of cross-correlation for 1500 particles needed about 1 minute.

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Development of 3-D Stereo PIV by Homogeneous Coordinate System (호모지니어스 좌표계를 이용한 3차원 스테레오 PIV 알고리듬의 개발)

  • Kim, Mi-Young;Choi, Jang-Woon;Nam, Koo-Man;Lee, Young-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.6
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    • pp.736-743
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    • 2003
  • A process of 3-D particle image velocimetry, called here, as '3-D stereo PIV' was developed for the measurement of an illuminated slied section field of 3-D complex flows. The present method includes modeling of camera by a calibrator based on the homogeneous coordinate system, transfromation of the oblique-angled image to the right-angled image, identification of 2-D velocity vectors by 2-D cross-correlation equation, stereo matching of 2-D velocity vectors of two cameras, accurate calculation of 3-D velocity vectors by homogeneous coordinate system, removal of error vectors by a statistical method followed by a continuity equation criterior, and finally 3-D animation as the post processing. An experimental system was also used for the application of the proposed method. Three analog CCD cameras and an Argon-Ion Laser(300mW) for illumination were adopted to capture the wake flow behind a bluff obstacle.

Development of 3-D Stereo PIV and Its Application to a Delta Wing

  • Kim, Beom-Seok;Lee, Hyun;Choi, Jang-Woon;Kadooka, Yoshimasa;Tago, Yoshio;Lee, Young-Ho
    • Proceedings of the KSME Conference
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    • 2003.11a
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    • pp.658-663
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    • 2003
  • A process of 3-D stereo particle image velocimetry(PIV)was developed for the measurement of an illuminated sliced section field of 3-D complex flows. The present method includes modeling of camera by a calibrator based on the homogeneous coordinate system, transformation of the oblique-angled image to the right-angled image, identification of 2-D velocity vectors by 2-D cross-correlation equation, stereo matching of 2-D velocity vectors of two cameras, accurate calculation of 3-D velocity vectors by homogeneous coordinate system, removal of error vectors by a statistical method followed by a continuity equation criteria, and finally 3-D display as the post processing. An experimental system was also used for the application of the proposed method. Two high speed digital CCD cameras and an Argon-Ion Laser for the illumination were adopted to clarify the time-dependent characteristics of the leading edge extension(LEX) in a highly swept shape applied to a delta wing found in modern air-fighters.

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Development of 3-D Stereo PIV (3차원 스테레오 PIV 개발)

  • Kim Mi-Young;Choi Jang-Woon;Nam Koo-Man;Lee Young-Ho
    • 한국가시화정보학회:학술대회논문집
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    • 2002.11a
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    • pp.19-22
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    • 2002
  • A process of 3-D particle image velocimetry, called here, as '3-D stereo PIV' was developed for the measurement of a section field of 3-D complex flows. The present method includes modeling of camera by a calibrator based on the homogeneous coordinate system, transfromation of oblique-angled image to transformed image, identification of 2-D velocity vectors by 2-D cross-correlation equation, stereo matching of 2-D velocity vectors of two cameras, accurate calculation of 3-D velocity vectors by homogeneous coordinate system and finally 3-D animation as the post processing. In principle, as two frame images only are necessary for the single instantaneous analysis of a section field of 3-D flow, more effective vectors are obtainable contrary to the previous multi-frame vector algorithm. An experimental system was also used for the application of the proposed method. Three analog CCD cameras and an Argon-Ion Laser(300mW) for illumination were adopted to capture the wake flow behind a bluff obstacle.

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Analysis of Correlation between Geometry Elements for the Efficient Use of Satellite Stereo Images (효율적인 스테레오 위성자료 활용을 위한 기하요소 간 상관성 분석)

  • Jeong, Jaehoon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.34 no.5
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    • pp.471-478
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    • 2016
  • This paper proposes the results of analysis of correlation between satellite geometry elements for an effective use of satellite images. To achieve accurate positional information, stereo images have normal range of convergence and BIE (BIsector Elevation) angles which are greatly influenced by azimuth and elevation angle of individual image. In this paper, the variations of convergence and BIE angles are estimated according to azimuth angle differences between two images and each elevation angle. The analysis provided strong support for predicting stereo geometry without complex analysis of epiploar geometry or mathematics. The experiment results showed that more than 150°, 130°, and 100° azimuth angle differences need to be constructed when elevation angle of two images is 50°, 60°, and 70°, respectively, in order to make the convergence and BIE angle within normal range. The results are expected to be fully used for various application using stereo images.

Stereocomplex Poly(lactic acid) Discoidal Microparticles for Sustained Drug Release (약물지연방출을 위한 스테레오컴플렉스 PLA 원반형 마이크로입자)

  • Park, Chaewon;Park, Sanghyo;Kim, Woo Cheol;Key, Jaehong
    • Journal of Biomedical Engineering Research
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    • v.41 no.1
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    • pp.62-66
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    • 2020
  • Controlled drug release is important for effective treatment of cancer. Poly(DL-lactide-co-glycolide) acid (PLGA) is a Food and Drug Administration (FDA) approved polymer and have been extensively studied as drug delivery carriers with biodegradable and biocompatible properties. However, PLGA drug delivery carriers are limited due to the initial burst release of drug. Certain drugs require an early rapid release, but in many cases the initial rapid release can be inefficient, reducing therapeutic effects and also increasing side effects. Therefore, sustained release is important for effective treatment. Poly Lactic Acid stereo complex (PLA SC) is resistant to hydrolysis and has high stability in aqueous solutions. Therefore, in this work, PLGA based discoidal polymeric particles are modified by Poly Lactic Acid stereocomplex (PLAsc DPPs). PLAsc DPPs are 3 ㎛ in diameter, also showing a relatively sustained release profile. Fluorescein 5(6)-isothiocyanate (FITC) released from PLAsc DPPs was continuously observed until 38 days, which showed the initial release of FITC from PLAsc DPPs was about 3.9-fold reduced as compared to PLGA based DPPs at 1 hour.

A Novel Feature Map Generation and Integration Method for Attention Based Visual Information Processing System using Disparity of a Stereo Pair of Images (주의 기반 시각정보처리체계 시스템 구현을 위한 스테레오 영상의 변위도를 이용한 새로운 특징맵 구성 및 통합 방법)

  • Park, Min-Chul;Cheoi, Kyung-Joo
    • The KIPS Transactions:PartB
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    • v.17B no.1
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    • pp.55-62
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    • 2010
  • Human visual attention system has a remarkable ability to interpret complex scenes with the ease and simplicity by selecting or focusing on a small region of visual field without scanning the whole images. In this paper, a novel feature map generation and integration method for attention based visual information processing system is proposed. The depth information obtained from a stereo pair of images is exploited as one of spatial visual features to form a set of topographic feature maps in our approach. Comparative experiments show that correct detection rate of visual attention regions improves by utilizing depth feature compared to the case of not using depth feature.

IKONOS Stereo Matching with Land Cover Map for DEM Generation

  • Lee, Hyo-Seong;Ahn, Ki-Weon;Park, Byung-Guk;Han, Dong-Yeob
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.580-583
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    • 2007
  • Various matching methods have been introduced by investigators to improve digital elevation model (DEM) accuracy of satellite imagery. This study proposed an area-based matching method according to land cover property using correlation coefficient of pixel brightness value between the two images for DEM generation from IKONOS stereo imagery. For this, matching line (where "matching line" implies straight line that is approximated to complex nonlinear epipolar geometry) is established by exterior orientation parameters to minimize search area. The matching is carried out based on this line. Land cover classes are divided off into water, urban land, forest and agricultural land. Matching size is selected using a correlation-coefficient image in the four areas. The selected sizes are $81{\times}81$ pixels window, $21{\times}21$ pixels window, $119{\times}119$ pixels window and $51{\times}51$ pixels window in the water area, urban land, forest land and agricultural land, respectively. And hence, DEM is generated from IKONOS stereo imagery using the selected matching sizes and land cover map on the four types.

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