We propose modeling that uses metaballs to create realistic clouds from satellite images. The method is intended for space flight simulators, visualization of the weather information, and simulation of surveys of the ...
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We propose modeling that uses metaballs to create realistic clouds from satellite images. The method is intended for space flight simulators, visualization of the weather information, and simulation of surveys of the earth, The density distribution inside the clouds is defined by a set of metaballs. The parameters (center positions, radii, and density values) are automatically determined so that the synthesized image is similar to the satellite image. We also propose an animation method for clouds generated by a sequence of satellite images taken at a given interval. We give several examples of clouds generated from satellite images of typhoons passing through Japan.
This paper presents an overview of our efforts in modeling-from-realty to create virtual reality models through observation of real objects. These efforts span three aspects: how to create geometric models of virtual ...
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ISBN:
(纸本)0769509843;0769509851
This paper presents an overview of our efforts in modeling-from-realty to create virtual reality models through observation of real objects. These efforts span three aspects: how to create geometric models of virtual objects;how to create photometric models of virtual objects;and how to integrate such virtual objects with real scenes. For geometric model creation, we have developed a two-step method: simultaneous alignment and volumetric view merging. For photometric model creation, we have developed two methods, model-based and eigen-texture rendering methods, both of which automatically create models by observing the real objects. For the integration of virtual objects with real scenes, we have developed a method that renders virtual objects based on real illumination distribution. We have successfully tested the proposed methods by using real images to demonstrate their effectiveness.
We present a system for 3D modeling of free-form surfaces from 2D sketches. Our system frees users to create 2D sketches from arbitrary angles using their preferred tool, which may include pencil and paper. A 3D model...
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ISBN:
(纸本)9781605588582
We present a system for 3D modeling of free-form surfaces from 2D sketches. Our system frees users to create 2D sketches from arbitrary angles using their preferred tool, which may include pencil and paper. A 3D model is created by placing primitives and annotations on the 2D image. Our primitives are based on commonly used sketching conventions and allow users to maintain a single view of the model. This eliminates the frequent view changes inherent to existing 3D modeling tools, both traditional and sketch-based, and enables users to match input to the 2D guide image. Our annotations-same-lengths and angles, alignment, mirror symmetry, and connection curves-allow the user to communicate higher-level semantic information;through them our system builds a consistent model even in cases where the original image is inconsistent. We present the results of a user study comparing our approach to a conventional "sketch-rotate-sketch" workflow.
Recently, computer graphics is widely used in movies and games, etc., and modeling three-dimensional virtual objects is important for synthesizing realistic images. Since modeling realistic objects often requires spec...
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ISBN:
(纸本)9781728122977
Recently, computer graphics is widely used in movies and games, etc., and modeling three-dimensional virtual objects is important for synthesizing realistic images. Since modeling realistic objects often requires special skills and takes long time, many methods have been developed to help the user generate models such as plants and buildings. However, little attention has been paid to the modeling of fish shapes because of the complexity of their shapes. We propose an interactive system for modeling a realistic fish shape from a single image. We also introduce a method called Direct Manipulation Blendshapes[1] for improving the usability of our system.
This paper introduces the meshfree Reproducing Kernel Particle Method (RKPM) in conjunction with a stabilized conforming nodal integration for 3D image-based modeling of skeletal muscles. This approach allows for cons...
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ISBN:
(纸本)9783319099941;9783319099934
This paper introduces the meshfree Reproducing Kernel Particle Method (RKPM) in conjunction with a stabilized conforming nodal integration for 3D image-based modeling of skeletal muscles. This approach allows for construction of simulation model based on pixel data obtained from medical images. The model consists of different materials and muscle fiber direction obtained from Diffusion Tensor Imaging (DTI) is input at each pixel point. The reproducing kernel (RK) approximation also allows a representation of material heterogeneity with smooth transition. A multiphase multichannel level set based segmentation using Magnetic Resonance images (MRI) and DTI formulated under a modified functional has been integrated into RKPM framework. The use of proposed methods for modeling the human lower leg is demonstrated.
Porous ceramic materials are in widespread use and continue to be developed as the key materials for many industrial fields. The mechanical properties of these porous materials are very sensitive to their 3-dimensiona...
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ISBN:
(纸本)0878499482
Porous ceramic materials are in widespread use and continue to be developed as the key materials for many industrial fields. The mechanical properties of these porous materials are very sensitive to their 3-dimensional structures. It is very important to analyze such materials taking into account their 3-dimensional morphology of the pore structure. An image-based modeling method using high resolution 3-dimensional computed tomography (CT) was developed, which makes it possible to reconstruct the complicated porous structures of porous ceramics nondestructively. From the 3-dimensional CT data, binary-processed images can be obtained and a voxel mesh computational analysis was carried out with a homogenization method, from which macroscopic and microscopic stress distribution for porous ceramics were possible to be calculated and visualized. From the 3-D CT image, a local microscopic model of the porous alumina was analyzed using voxel mesh method of mathematical homogenization method. Using the data the microscopic local stress distribution of the model was obtained.
We propose a method of three-dimensional (3D) modeling of volumetric fluid phenomena from sparse multi-view images (e.g., only a single-view input or a pair of front- and side-view inputs). The volume determined from ...
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We propose a method of three-dimensional (3D) modeling of volumetric fluid phenomena from sparse multi-view images (e.g., only a single-view input or a pair of front- and side-view inputs). The volume determined from such sparse inputs using previous methods appears blurry and unnatural with novel views;however, our method preserves the appearance of novel viewing angles by transferring the appearance information from input images to novel viewing angles. For appearance information, we use histograms of image intensities and steerable coefficients. We formulate the volume modeling as an energy minimization problem with statistical hard constraints, which is solved using an expectation maximization (EM)-like iterative algorithm. Our algorithm begins with a rough estimate of the initial volume modeled from the input images, followed by an iterative process whereby we first render the images of the current volume with novel viewing angles. Then, we modify the rendered images by transferring the appearance information from the input images, and we thereafter model the improved volume based on the modified images. We iterate these operations until the volume converges. We demonstrate our method successfully provides natural-looking volume sequences of fluids (i.e., fire, smoke, explosions, and a water splash) from sparse multiview videos. To create production-ready fluid animations, we further propose a method of rendering and editing fluids using a commercially available fluid simulator.
In this thesis, we address the problem of 3D reconstruction from a sequence of cali- brated street-level photographs with a simultaneous focus on scalability and the use of structure priors in Multi-View Stereo (MVS)....
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In this thesis, we address the problem of 3D reconstruction from a sequence of cali- brated street-level photographs with a simultaneous focus on scalability and the use of structure priors in Multi-View Stereo (MVS). While both aspects have been studied broadly, existing scalable MVS approaches do not handle well the ubiquitous structural regularities, yet simple, of man-made envi- ronments. On the other hand, structure-aware 3D reconstruction methods are slow and scale poorly with the size of the input sequences and/or may even require additional restrictive information. The goal of this thesis is to reconcile scalability and structure- awareness within common MVS grounds using soft, generic priors which encourage: (i) piecewise planarity, (ii) alignment of objects boundaries with image gradients and (iii) with vanishing directions (VDs), and (iv) objects co-planarity. To do so, we present the novel "Patchwork Stereo" framework which integrates photometric stereo from a handful of wide-baseline views and a sparse 3D point cloud combining robust 3D plane extraction and top-down image partitioning from a unified 2D-3D analysis in a princi- pled Markov Random Field energy minimization. We evaluate our contributions quantitatively and qualitatively on challenging urban datasets and illustrate results which are at least on par with state-of-the-art methods in terms of geometric structure, but achieved in several orders of magnitude faster paving the way for photo-realistic city-scale modeling.
This paper presents an image-based three-dimensional (3-D) reverse modeling system. We take advantage of stereo vision-based method to acquire geometric information through sampling the surface of a physical object mo...
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ISBN:
(纸本)9781424402588
This paper presents an image-based three-dimensional (3-D) reverse modeling system. We take advantage of stereo vision-based method to acquire geometric information through sampling the surface of a physical object mounted on end effectors of a 4-DOF planar robot. based on real-world sampling datasets, a realistic 3-D graphical model can be automatically constructed. We provide a new approach to system calibration, geometric information acquisition, and surface parameterization, and also implement a prototype system of rapidly establishing textured model that is available to virtual reality application.
This paper presents a novel approach to automatically generate a plausible 3D model from a single outdoor image. Outdoor scene can be modeled as a set of planar billboards such as ground, sky and vertical trees or bui...
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ISBN:
(纸本)9781479947171
This paper presents a novel approach to automatically generate a plausible 3D model from a single outdoor image. Outdoor scene can be modeled as a set of planar billboards such as ground, sky and vertical trees or buildings. This Cut-and-Fold system takes the advantages of the statistical classification method for high-level geometric labeling of the image regions and the automatic image segmentation algorithm for detailed boundaries of the geometric regions to generate accurate geometric labeling and realistic rendering of novel views. Taking a single image as input, our method first roughly classifies each sub-region to the geometric categories: vertical, ground or sky. Then image segmentation algorithm is employed to refine the labeling results and generate accurate boundaries for the geometric regions. After cutting the image into several regions with their geometric labels, the system folds the regions into 3D billboards with accurate boundaries. The experimental results demonstrate that our method is capable of creating plausible 3D models automatically for a wide range of outdoor scenes.
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