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 no...
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ISBN:
(纸本)9781581137095
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.
In this paper, we describe a purely image-based system that allows a user to interactively capture the 3D geometry of a polyhedral scene with the aid of its physical presence. A video camera is used as both an interac...
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ISBN:
(纸本)9781424453887
In this paper, we describe a purely image-based system that allows a user to interactively capture the 3D geometry of a polyhedral scene with the aid of its physical presence. A video camera is used as both an interaction and tracking device. The 3D user interface is intuitive to a non-expert and the mouseless control procedure makes the system particularly suitable for mobile devices such as PDAs and mobile phones. The efficiency and accuracy of the method are demonstrated on a polyhedral scene made of two house-like boxes.
Computational modeling has been promulgated as a means of optimizing artificial bone tissue culturing ex vivo. In the present report, we show, as a proof-of-concept, that it is possible to model the exact microenviron...
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Computational modeling has been promulgated as a means of optimizing artificial bone tissue culturing ex vivo. In the present report, we show, as a proof-of-concept, that it is possible to model the exact microenvironment within the scaffolds while accounting for their architectural complexities and the presence of cells/tissues in their pores. Our results clearly indicate that image-based modeling has the potential to be a powerful tool for computer-assisted tissue engineering.
作者：
Rossi, D.Univ Camerino
Scuola Architettura & Design E Vittoria I-62032 Camerino Italy
The main focus of this article is to explain a teaching activity. This experience follows a research aimed to testing innovative systems for formal and digital analysis of architectural building. In particular, the fi...
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The main focus of this article is to explain a teaching activity. This experience follows a research aimed to testing innovative systems for formal and digital analysis of architectural building. In particular, the field of investigation is the analytical drawing. An analytical draw allows to develope an interpretative and similar models of reality;these models are built using photomodeling techniques and are designed to re-mTite modern and contemporary architecture. The typology of the buildings surveyed belong to a cultural period, called Modern Movement, historically placed between the two world wars. The Modern Movement aimed to renew existing architectural principle and to a functional redefinition of the same one. In Italy these principles arrived during the Fascist period. Heritage made up of public social buildings (case del Balilla, GIL., recreation center...) built during the fascist period in middle Italy is remarkable for quantity and in many cases for architectural quality. This kind of buildings arc composed using pure shapes: large cube (gyms) alternate with long rectangular block containing offices creates compositions made of big volumes and high towers. These features are perfectly suited to the needs of a surveying process by photomodeling where the role of photography is central and where there is the need to identify certain and easily distinguishable points on all picture, leaning on the edges of the volume or lininig on the texture discontinuity. The goal is the documentation to preserve and to develop buildings and urban complexes of modern architecture, directed to encourage an artistic preservation.
In order to enable high-speed operation of scanning probe microscopes (SPMs), a dynamic model of the SPM's lateral nanopositioner is typically required (e.g for model inverse feedforward control). One of the prima...
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In order to enable high-speed operation of scanning probe microscopes (SPMs), a dynamic model of the SPM's lateral nanopositioner is typically required (e.g for model inverse feedforward control). One of the primary difficulties associated with developing such models is the availability of nanoposition sensors, especially in very high resolution systems. In order to overcome this problem, a method capable of finding models of the individual SPM nanopositioner axes using only the SPM's imaging capabilities is presented. Specifically, images of a calibration sample acquired using a spiral scan trajectory are analyzed to determine frequency response information for the SPM's lateral positioning axes. The method is presented, followed by simulation results that show the feasibility of the approach.
We propose a framework that extends Blender to exploit Structure from Motion (SfM) and Multi-View Stereo (MVS) techniques for image-based modeling tasks such as sculpting or camera and motion tracking. Applying SfM al...
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ISBN:
(纸本)9789897584886
We propose a framework that extends Blender to exploit Structure from Motion (SfM) and Multi-View Stereo (MVS) techniques for image-based modeling tasks such as sculpting or camera and motion tracking. Applying SfM allows us to determine camera motions without manually defining feature tracks or calibrating the cameras used to capture the image data. With MVS we are able to automatically compute dense scene models, which is not feasible with the built-in tools of Blender. Currently, our framework supports several state-of-the-art SfM and MVS pipelines. The modular system design enables us to integrate further approaches without additional effort. The framework is publicly available as an open source software package.
Creating 3D tree models from actual trees is a task receiving increasing attention. Some approaches have been developed to reconstruct a tree based on a number of photographs around the tree, typically spanning a wide...
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Creating 3D tree models from actual trees is a task receiving increasing attention. Some approaches have been developed to reconstruct a tree based on a number of photographs around the tree, typically spanning a wide viewing range. However, due to the environmental restrictions, sometimes it is quite difficult to capture so many acceptable images from so many different viewpoints. In this paper, we propose a tree modeling system which is capable of reconstructing the 3D model of a tree from a few images with very narrow viewing ranges. Because only a few images are required to generate the model, our system has the distinct advantage of fewer environmental restrictions, resulting in the extended usability and flexibility for real applications.
The potential of image-based computational modeling for determining the microstructural features that cause initial plastic flow (yield) in metals is investigated using a beta-Ti alloy as the focus material. A high-fi...
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The potential of image-based computational modeling for determining the microstructural features that cause initial plastic flow (yield) in metals is investigated using a beta-Ti alloy as the focus material. A high-fidelity three-dimensional (3-D) morphological and crystallographic description of approximately 100 metallic grains is embedded into crystal plasticity finite-element models to analyze the microscale heterogeneity of material response under a set of loading conditions applied at the mesoscale. Preliminary results show that regardless of the globally applied loading condition most of the plastic flow initially occurs generally within only one of the two grains at a grain boundary. Additionally, it was determined that initial local plastic slip is suppressed in a compliant grain neighbored by relatively stiff grains under multiple loading conditions. Overall, the analysis demonstrates that the image-based modeling framework should be used in conjunction with sophisticated data-mining tools for identification of microstructure-property correlations in polycrystalline metals provided a statistically relevant number of grains are accommodated in the models. However, smaller volumes may still be used to investigate the local effect of microstructural features on mechanical behavior. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
This paper describes a new approach for image-based modelingbased on thermographic images and applied to efficiency energy studies of building facades. The approach is automatic and allows obtaining thermographic 3D ...
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This paper describes a new approach for image-based modelingbased on thermographic images and applied to efficiency energy studies of building facades. The approach is automatic and allows obtaining thermographic 3D models and orthoimages, which can be used to assess energy efficiency of building facades. The classical photogrammetry approach is reinforced and combined with computer vision algorithms, especially for the processes of image matching and dense surface generation, so that they have a robust performance with thermographic images. Experimental results presented here demonstrate the capability of the proposed approach using the Polytechnic Advanced School of Avila (Spain) as a case of study. (c) 2013 Elsevier B.V. All rights reserved.
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