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Match propagation for image-based modeling and rendering

IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE 2002年第8期24卷 1140-1146页

作者： Lhuillier, M Quan, L HKUST Dept Comp Sci Kowloon Hong Kong Peoples R China

This paper presents a quasi-dense matching algorithm between images based on the match propagation principle. The algorithm starts from a set of sparse seed matches, then propagates to the neighboring pixels by the best-first strategy, and produces a quasi-dense disparity map. The quasi-dense matching aims at broad modeling and visualization applications which rely heavily on matching information. Our algorithm is robust to initial sparse match outliers due to the best-first strategy. It is efficient in time and space as it is only output sensitive. It handles half-occluded areas because of the simultaneous enforcement of newly introduced discrete 2D gradient disparity limit and the uniqueness constraint. The properties of the algorithm are discussed and empirically demonstrated. The quality of quasi-dense matching are validated through intensive real examples.

关键词： quasi-dense matching stereo vision image-based modeling rendering

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Prediction of Non-Darcy Coefficients for Inertial Flows Through the Castlegate Sandstone Using image-based modeling

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TRANSPORT IN POROUS MEDIA 2012年第3期95卷 563-580页

作者： Chukwudozie, C. P. Tyagi, M. Sears, S. O. White, C. D. Louisiana State Univ & A&M Coll Ctr Computat & Technol Baton Rouge LA 70803 USA Louisiana State Univ & A&M Coll Craft & Hawkins Dept Petr Engn Baton Rouge LA 70803 USA

Near wellbore flow in high rate gas wells shows the deviation from Darcy's law that is typical for high Reynolds number flows, and prediction requires an accurate estimate of the non-Darcy coefficient (beta factor). This numerical investigation addresses the issues of predicting non-Darcy coefficients for a realistic porous media. A CT-image of real porous medium (Castlegate Sandstone) was obtained at a resolution of 7.57 mu m. The segmented image provides a voxel map of pore-grain space that is used as the computational domain for the lattice Boltzmann method (LBM) based flow simulations. Results are obtained for pressure-driven flow in the above-mentioned porous media in all directions at increasing Reynolds number to capture the transition from the Darcy regime as well as quantitatively predict the macroscopic parameters such as absolute permeability and beta factor (Forchheimer coefficient). Comparison of numerical results against experimental data and other existing correlations is also presented. It is inferred that for a well-resolved realistic porous media images, LBM can be a useful computational tool for predicting macroscopic porous media properties such as permeability and beta factor.

关键词： Non-Darcy flow Forchheimer equation image-based modeling Lattice Boltzmann method Castlegate sandstone

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Support vector machine guided reproducing kernel particle method for image-based modeling of microstructures

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COMPUTATIONAL MECHANICS 2024年第4期73卷 907-942页

作者： Wang, Yanran Baek, Jonghyuk Tang, Yichun Du, Jing Hillman, Mike Chen, Jiun-Shyan Univ Calif San Diego Dept Struct Engn La Jolla CA 92093 USA Penn State Univ Dept Mech Engn University Pk PA 16802 USA Karagozian & Case Inc Glendale CA 91203 USA

This work presents an approach for automating the discretization and approximation procedures in constructing digital representations of composites from micro-CT images featuring intricate microstructures. The proposed method is guided by the Support Vector Machine (SVM) classification, offering an effective approach for discretizing microstructural images. An SVM soft margin training process is introduced as a classification of heterogeneous material points, and image segmentation is accomplished by identifying support vectors through a local regularized optimization problem. In addition, an Interface-Modified Reproducing Kernel Particle Method (IM-RKPM) is proposed for appropriate approximations of weak discontinuities across material interfaces. The proposed method modifies the smooth kernel functions with a regularized Heaviside function concerning the material interfaces to alleviate Gibb's oscillations. This IM-RKPM is formulated without introducing duplicated degrees of freedom associated with the interface nodes commonly needed in the conventional treatments of weak discontinuities in the meshfree methods. Moreover, IM-RKPM can be implemented with various domain integration techniques, such as Stabilized Conforming Nodal Integration (SCNI). The extension of the proposed method to 3-dimension is straightforward, and the effectiveness of the proposed method is validated through the image-based modeling of polymer-ceramic composite microstructures.

关键词： image-based modeling Support vector machine Reproducing kernel particle method Weak discontinuity Microstructures

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High-resolution depth for binocular image-based modeling

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COMPUTERS & GRAPHICS-UK 2014年第1期39卷 89-100页

作者： Blumenthal-Barby, David C. Eisert, Peter Fraunhofer Heinrich Hertz Inst Berlin Germany Humboldt Univ D-10099 Berlin Germany

We propose a binocular stereo method which is optimized for reconstructing surface detail and exploits the high image resolutions of current digital cameras. Our method occupies a middle ground between stereo algorithms focused on depth layering of cluttered scenes and multi-view "object reconstruction" approaches which require a higher view count. It is based on global non-linear optimization of continuous scene depth rather than discrete pixel disparities. We propose a mesh-based data-term for large images, and a smoothness term using robust error norms to allow detailed surface geometry. We show that the continuous optimization approach enables interesting extensions beyond the core algorithm: Firstly, with small changes to the data-term camera parameters instead of depth can be optimized in the same framework. Secondly, we argue that our approach is well suited for a semi-interactive reconstruction work-flow, for which we propose several tools. (C) 2013 Elsevier Ltd. All rights reserved.

关键词： 3D reconstruction image-based modeling Optimization Interaction in 3D reconstruction

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Three-dimensional image-based modeling of lotus-type porous carbon steel and simulation of its mechanical behavior by finite element method

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MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING 2007年 460卷 220-226页

作者： Kujime, T. Tane, M. Hyun, S. K. Nakajima, H. Osaka Univ Inst Sci & Ind Res Osaka 5670047 Japan

Lotus-type porous carbon steel with cylindrical pores was fabricated by the continuous zone melting method in pressurized hydrogen gas. A three-dimensional (3D) reconstruction of the microstructure of the lotus-type porous car bon steel was made by using an image-based modeling to simulate the mechanical behavior. The stress-strain behavior of the 3D models of the lotus-type porous carbon steel was predicted by using finite element method (FEM) and was compared with the experimental results. Until the strain reaches 0.05, the compressive stress of the predicted model reaches the almost same value of the experimental result. The tensile stress also reaches approximately 0.9 times value of the experimental result. (C) 2007 Elsevier B.V. All rights reserved.

关键词： lotus-type porous steel zone melting mechanical behavior finite element analysis image-based modeling

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Putting the User in the Loop for image-based modeling

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INTERNATIONAL JOURNAL OF COMPUTER VISION 2014年第1-2期108卷 30-48页

作者： Kowdle, Adarsh Chang, Yao-Jen Gallagher, Andrew Batra, Dhruv Chen, Tsuhan Cornell Univ Ithaca NY 14853 USA Siemens Corp Corp Technol Princeton NJ USA Virginia Tech Blacksburg VA USA

We refer to the task of recovering the 3D structure of an object or a scene using 2D images as image-based modeling. In this paper, we formulate the task of recovering the 3D structure as a discrete optimization problem solved via energy minimization. In this standard framework of a Markov random field (MRF) defined over the image we present algorithms that allow the user to intuitively interact with the algorithm. We introduce an algorithm where the user guides the process of image-based modeling to find and model the object of interest by manually interacting with the nodes of the graph. We develop end user applications using this algorithm that allow object of interest 3D modeling on a mobile device and 3D printing of the object of interest. We also propose an alternate active learning algorithm that guides the user input. An initial attempt is made at reconstructing the scene without supervision. Given the reconstruction, an active learning algorithm uses intuitive cues to quantify the uncertainty of the algorithm and suggest regions, querying the user to provide support for the uncertain regions via simple scribbles. These constraints are used to update the unary and the pairwise energies that, when solved, lead to better reconstructions. We show through machine experiments and a user study that the proposed approach intelligently queries the users for constraints, and users achieve better reconstructions of the scene faster, especially for scenes with textureless surfaces lacking strong textural or structural cues that algorithms typically require.

关键词： image-based modeling Interactive 3D reconstruction Active-learning Energy minimization

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Radiance-based color calibration for image-based modeling with multiple cameras

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Science China(Information Sciences) 2012年第7期55卷 1509-1519页

作者： ZHAO Xu 1,2 ,ZHOU Zhong 1,2 & WU Wei 1,2 1 State Key Laboratory of Virtual Reality Technology and Systems,Beihang University,Beijing 100191,China 2 School of Computer Science and Engineering,Beihang University,Beijing 100191,China 1. State Key Laboratory of Virtual Reality Technology and Systems Beihang University Beijing 100191 China2. School of Computer Science and Engineering Beihang University Beijing 100191 China

Photo-consistency estimation is an important part for many image-based modeling *** paper presents a novel radiance-based color calibration method to reduce the uncertainty of photo-consistency estimation across multiple *** idea behind our method is to convert colors into a uniform radiometric color space in which multiple image data are *** results demonstrate that our method can achieve comparable color calibration effect without adjusting camera parameters and is more robust than other existing ***,we obtain an auto-determined threshold for photo-consistency check,which will lead to a better performance than existing photo-consistency based reconstruction algorithms.

关键词： color calibration photo-consistency estimation multi-camera system image-based modeling

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Nonlinear optimization framework for image-based modeling on programmable graphics hardware

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ACM TRANSACTIONS ON GRAPHICS 2003年第3期22卷 925-934页

作者： Hillesland, KE Molinov, S Grzeszczuk, R Univ N Carolina Chapel Hill NC 27514 USA Intel Corp Santa Clara CA 95051 USA

Graphics hardware is undergoing a change from fixed-function pipelines to more programmable organizations that resemble general purpose stream processors. In this paper, we show that certain general algorithms, not normally associated with computer graphics, can be mapped to such designs. Specifically, we cast nonlinear optimization as a data streaming process that is well matched to modem graphics processors. Our framework is particularly well suited for solving image-based modeling problems since it can be used to represent a large and diverse class of these problems using a common formulation. We successfully apply this approach to two distinct image-based modeling problems: light field mapping approximation and fitting the Lafortune model to spatial bidirectional reflectance distribution functions. Comparing the performance of the graphics hardware implementation to a CPU implementation, we show more than 5-fold improvement.

关键词： programmable graphics hardware nonlinear optimization. image-based modeling

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From image-based modeling to the modeling of Imaging with the Virtual Population 1st

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1st International Workshop on Simulation and Synthesis in Medical Imaging (SASHIMI)

作者： Neufeld, Esra Lloyd, Bryn Kuster, Niels ITIS Fdn Res Informat Technol Soc CH-8004 Zurich Switzerland Swiss Fed Inst Technol ETHZ CH-8092 Zurich Switzerland

ISBN: (纸本)9783319466309;9783319466293

image data has been used to create the Virtual Population models, a range of highly detailed anatomical models (male/female,neonates/children/adults/ elderly, average build/obese) which have been found to be useful for a wide range of computational life sciences applications. They are at the core of the Sim4Life simulation platform. Different image modalities provide a wealth of information enabling model functionalization by facilitating anatomy parameterization and animation, consideration of tissue inhomogeneity, imposition of realistic boundary conditions, and integration of dynamic physiological models. Closing the circle, these functionalized anatomical models have also been used to generate virtual image data, particularly by simulating MR imaging. Thus, image data can be produced under controlled conditions and with known base-anatomy for different pulse sequences. Virtual imaging has been used to study different imaging artefacts.

关键词： Virtual Population Anatomical phantoms image-based modeling Model functionalization MRI simulation

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Application and Research of image-based modeling and 3D Printing Technology in Intangible Cultural Heritage Quanzhou Marionette Protection 43

Application and Research of Image-Based Modeling and 3D Prin...

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43rd IEEE-Computer-Society Annual International Computers, Software and Applications Conference (COMPSAC)

作者： Gao, Chao Yao, Junfeng Huang, Kaini Qian, Kai Xiamen Univ Ctr Digital Media Comp Software Sch Xiamen Peoples R China Kennesaw State Univ Coll Comp & Software Engn Kennesaw GA 30144 USA

ISBN: (纸本)9781728126074

We present a practical solution to the modeling improvements for Quanzhou Marionette in 3D printing. We use 3D printing technology to improve the marionette production process. We have completed rapid image-based modeling to aid in design. According to the actual situation, the special parts such as marionette heads and joints are modeled and improved. The experiment proves the advantages of 3D printing in marionette production. 3D printing can be used as a production tool method for the protection and inheritance of intangible cultural heritage.

关键词： Marionette 3D Printing image-based modeling

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