• Title/Summary/Keyword: 3D image reconstruction

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Human Face Recognition and 3-D Human Face Modelling (얼굴 영상 인식 및 3차원 얼굴 모델 구현 알고리즘)

  • 이효종;이지항
    • Proceedings of the IEEK Conference
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    • 2000.11c
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    • pp.113-116
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    • 2000
  • Human face recognition and 3D human face reconstruction has been studied in this paper. To find the facial feature points, find edge from input image and analysis the accumulated histogram of edge information. This paper use a Generic Face Model to display the 3D human face model which was implement with OpenGL and generated with 500 polygons. For reality of 3D human face model, we propose Group matching mapping method between facial feature points and the one of Generic Face Model. The personalized 3D human face model which resembles real human face can be generated automatically in less than 5 seconds on Pentium PC.

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Determination and Visualization of Three-Dimensional Shape Based on Images (영상 기반 3차원 형상 추출 및 가시화)

  • Cho Jung-Ho;Song Moon-Ho
    • 한국가시화정보학회:학술대회논문집
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    • 2002.11a
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    • pp.15-18
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    • 2002
  • We propose an image based three-dimensional shape determination system. The shape, and thus the three-dimensional coordinate information of the 3-D object, is determined solely from captured images of the 3-D object from a prescribed set of viewpoints. The approach is based on the shape from silhouette (SFS) technique and the efficacy of the SFS method is tested using a sample data set. This system may be used to visualize the 3-D object efficiently, or to quickly generate initial CAD data for reverse engineering purposes. The proposed system potentially may be used in three dimensional design applications such as 3-D animation and 3-D games.

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Measurement Accuracy for 3D Structure Shape Change using UAV Images Matching (UAV 영상정합을 통한 구조물 형상변화 측정 정확도 연구)

  • Kim, Min Chul;Yoon, Hyuk Jin;Chang, Hwi Jeong;Yoo, Jong Soo
    • Journal of Korean Society for Geospatial Information Science
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    • v.25 no.1
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    • pp.47-54
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    • 2017
  • Recently, there are many studies related aerial mapping project and 3 dimensional shape and model reconstruction using UAV(unmanned aerial vehicle) system and images. In this study, we create 3D reconstruction point data using image matching technology of the UAV overlap images, detect shape change of structure and perform accuracy assessment of area($m^2$) and volume($m^3$) value. First, we build the test structure model data and capturing its images of shape change Before and After. Second, for post-processing the Before dataset is convert the form of raster format image to ensure the compare with all 3D point clouds of the After dataset. The result shows high accuracy in the shape change of more than 30 centimeters, but less is still it becomes difficult to apply because of image matching technology has its own limits. But proposed methodology seems very useful to detect illegal any structures and the quantitative analysis of the structure's a certain amount of damage and management.

3-D DISPLAY USING COMPUTER-GENERATED BINARY HOLOGRAMS

  • Yoshinori-Kajiki;Masaaki-Okamoto;Koji-Yamasaki;Eiji-Shimizu
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 1999.06a
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    • pp.227-232
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    • 1999
  • We have been making researches on 3-D displays using computer-generated holograms(CGHs). Our CGHs are binary Fresnel holograms that reconstruct point light sources and are recorded by using high resolution laser printers (image setters). We use an image setter with a resolution of 5080 dots per inch. It is possible to reconstruct CGHs with light-emitting points. As the resolution of the image setter is not so high, it is better to use a spherical wave as a reference beam. We considered the recordable points objects are restricted by the low resolution, and proposed the multiplex type hologram to reduce the number of point objects recorded in the unit area of the CGH. We proposed a method to make computer-generated color hologram which could reconstruct color point light sources, by combining RGB color filters with the stripe CGHs corresponding to each color. We considered two kinds of gradation method on our binary CGHs. In this paper, we propose a multiple reconstruction method for improving the narrow viewing field.

A Method for Generation of Contour lines and 3D Modeling using Depth Sensor (깊이 센서를 이용한 등고선 레이어 생성 및 모델링 방법)

  • Jung, Hunjo;Lee, Dongeun
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.12 no.1
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    • pp.27-33
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    • 2016
  • In this study we propose a method for 3D landform reconstruction and object modeling method by generating contour lines on the map using a depth sensor which abstracts characteristics of geological layers from the depth map. Unlike the common visual camera, the depth-sensor is not affected by the intensity of illumination, and therefore a more robust contour and object can be extracted. The algorithm suggested in this paper first abstracts the characteristics of each geological layer from the depth map image and rearranges it into the proper order, then creates contour lines using the Bezier curve. Using the created contour lines, 3D images are reconstructed through rendering by mapping RGB images of the visual camera. Experimental results show that the proposed method using depth sensor can reconstruct contour map and 3D modeling in real-time. The generation of the contours with depth data is more efficient and economical in terms of the quality and accuracy.

A Measurement Method for Cervical Neural Foraminal Stenosis Ratio using 3-dimensional CT (3차원 컴퓨터단층촬영상을 이용한 신경공 협착률 측정방법)

  • Kim, Yon-Min
    • Journal of the Korean Society of Radiology
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    • v.14 no.7
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    • pp.975-980
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    • 2020
  • Cervical neural foraminal stenosis is a very common spinal disease that affects a relatively large number of people of all ages. However, since imaging methods that quantitatively provide neural foraminal stenosis are lacking, this study attempts to present quantitative measurement results by reconstructing 3D computed tomography images. Using a 3D reconstruction software, the surrounding bones were removed, including the spinous process, transverse process, and lamina of the cervical spine so that the neural foramen were well observed. Using Image J, a region of interest including the neural foramen area of the 3D image was set, and the number of pixels of the neural foramen area was measured. The neural foramen area was calculated by multiplying the number of measured pixels by the pixel size. In order to measure the widest area of the neural foramen, it was measured between 40-50 degrees in the opposite direction and 15-20 degrees toward the head. The measured cervical neural foramen area showed consistent measurement values. The largest measured area of the right neural foramen C5-6 was 12.21 ㎟, and after 2 years, the area was measured to be 9.95 ㎟, indicating that 18% stenosis had progressed. Since 3D reconstruction using axial CT scan images, no additional radiation exposure is required, and the area of stenosis can be objectively presented. In addition, it is good to explain to patients with neural stenosis while viewing 3D images, and it is considered a good method to be used in the evaluation of the progression of stenosis and post-operative evaluation.

Optical Implementation of Three-Dimensional Image using Modified Triangular Interferometer (변형 삼각간섭계를 이용한 3차원 영상의 광학적 구현)

  • 김수길
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.18 no.1
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    • pp.15-20
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    • 2004
  • We presented the optical reconstruction system of complex hologram and theoretically demonstrated that the proposed system could display complex hologram. And we made the complex hologram of a three-dimensional image using the modified triangular interferometer, and presented and analyzed the three-dimensional images numerically and optically reconstructed from it.

CGS System based on Three-Dimensional Character Modeling I (Part1:About Non-Digital Process) (3차원 캐릭터 모델기반 CGS System 구축 I (Part1:Non-Digital Process에 관하여))

  • Cho, Dong-Min
    • Journal of Korea Multimedia Society
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    • v.11 no.11
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    • pp.1592-1600
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    • 2008
  • This study is to help creative idea generation based on the theory of the 'reconstruction of character shape image elements', and aims to extrusion of creative and diverse shapes with combination of image elements upon computing creative image generation. In order to suggest the design generation methodology for the maximization of idea generation ability and to overcome restriction of thinking out of existing idea generation methodology, it has suggested the CGS(Character Generation System) that is a creative idea generation methodology identified and complemented the problem of the existing computerized idea generation(PDS with Proportion) method out of the preceded studies on the creative idea generation methodologies. this study is expected to have effectives as one method for idea generation or creative image generation assistance during the 3D character development process, and to serve as an assistance to overcome the restriction of the character shape image generation through diverse idea generations.

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Numerical analysis of the thermal behaviors of cellular concrete

  • She, Wei;Zhao, Guotang;Yang, Guotao;Jiang, Jinyang;Cao, Xiaoyu;Du, Yi
    • Computers and Concrete
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    • v.18 no.3
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    • pp.319-336
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    • 2016
  • In this study, both two- and three-dimensional (2D and 3D) finite-volume-based models were developed to analyze the heat transfer mechanisms through the porous structures of cellular concretes under steady-state heat transfer conditions and to investigate the differences between the 2D and 3D modeling results. The 2D and 3D reconstructed pore networks were generated from the microstructural information measured by 3D images captured by X-ray computerized tomography (X-CT). The computed effective thermal conductivities based on the 2D and 3D calculations performed on the reconstructed porous structures were found to be nearly identical to those evaluated from the 2D cross-sectional images and the 3D X-CT images, respectively. In addition, the 3D computed effective thermal conductivity was found to agree better with the measured values, in comparison with the 2D reconstruction and real cross-sectional images. Finally, the thermal conductivities computed for different reconstructed porous 3D structures of cellular concretes were compared with those obtained from 2D computations performed on 2D reconstructed structures. This comparison revealed the differences between 2D and 3D image-based modeling. A correlation was thus derived between the results of the 3D and 2D models.

3D surface Reconstruction of Moving Object Using Multi-Laser Stripes Irradiation (멀티 레이저 라인 조사를 이용한 비등속 이동물체의 3차원 형상 복원)

  • Yi, Young-Youl;Ye, Soo-Young;Nam, Ki-Gon
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.44 no.2 s.314
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    • pp.144-152
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    • 2007
  • We propose a 3D modeling method for surface inspection of non-linear moving object. The laser lines reflect the surface curvature. We can acquire 3D surface information by analyzing projected laser lines on object. ill this paper, we use multi-line laser to make use of robust of single stripe method and high speed of single frame. Binarization and channel edge extraction method were used for robust laser line extraction. A new labeling method was used for laser line labeling. We acquired sink information between each 3D reconstructed frame by feature point matching, and registered each frame to one whole image. We verified the superiority of proposed method by applying it to container damage inspection system.