29-Issue 1

Permanent URI for this collection

https://diglib.eg.org/handle/10.2312/152

Editorial

[meta data] [files: ]
Scopigno, Roberto
; 
Groeller, Eduard

Simplifying Character Skins with Analytic Error Metrics

[meta data] [files: ]
Merry, B.
; 
Marais, P.
; 
Gain, J.

Afrigraph: The African Computer Graphics Association and its Activities

[meta data] [files: ]
Gain, J.
; 
Strasser, W.
; 
Hardy, A.
; 
Marais, P.

Evaluation of an Augmented Reality Supported Picking System Under Practical Conditions

[meta data] [files: ]
Reif, R.
; 
Guenthner, W. A.
; 
Schwerdtfeger, B.
; 
Klinker, G.

Meshless Shape and Motion Design for Multiple Deformable Objects

[meta data] [files: ]
Adams, B.
; 
Wicke, M.
; 
Ovsjanikov, M.
; 
Wand, M.
; 
Seidel, H.-P.
; 
Guibas, L. J.

Modelling the Appearance and Behaviour of Urban Spaces

[meta data] [files: ]
Vanegas, C. A.
; 
Aliaga, D. G.
; 
Wonka, P.
; 
Mueller, P.
; 
Waddell, P.
; 
Watson, B.

Time-Dependent 2-D Vector Field Topology: An Approach Inspired by Lagrangian Coherent Structures

[meta data] [files: ]
Sadlo, F.
; 
Weiskopf, D.

Hybrid Booleans

[meta data] [files: ]
Pavic, Darko
; 
Campen, Marcel
; 
Kobbelt, Leif

Fast Gauss Bilateral Filtering

[meta data] [files: ]
Yoshizawa, Shin
; 
Belyaev, Alexander
; 
Yokota, Hideo

SPC: Fast and Efficient Scalable Predictive Coding of Animated Meshes

[meta data] [files: ]
Stefanoski, Nikolce
; 
Ostermann, Joern

Embedded Implicit Stand-Ins for Animated Meshes: A Case of Hybrid Modelling

[meta data] [files: ]
Kravtsov, D.
; 
Fryazinov, O.
; 
Adzhiev, V.
; 
Pasko, A.
; 
Comninos, P.

Adaptive and Feature-Preserving Subdivision for High-Quality Tetrahedral Meshes

[meta data] [files: ]
Burkhart, D.
; 
Hamann, B.
; 
Umlauf, G.

Constrained Texture Mapping using Image Warping

[meta data] [files: ]
Seo, H.
; 
Cordier, F.

Time-of-Flight Cameras in Computer Graphics

[meta data] [files: ]
Kolb, A.
; 
Barth, E.
; 
Koch, R.
; 
Larsen, R.

Multi-Perspective Modelling, Rendering and Imaging

[meta data] [files: ]
Yu, J.
; 
McMillan, L.
; 
Sturm, P.

Bidirectional Texture Function Compression Based on Multi-Level Vector Quantization

[meta data] [files: ]
Havran, V.
; 
Filip, J.
; 
Myszkowski, K.

Eurographics 2009 Workshop on 3D Object Retrieval (EG 3DOR 09) in Cooperation with ACM SIGGRAPH Munich, Germany March 29, 2009

[meta data] [files: ]
Pratikakis, Ioannis
; 
Spagnuolo, Michela

State of the Art in Example-Based Motion Synthesis for Virtual Characters in Interactive Applications

[meta data] [files: ]
Pejsa, T.
; 
Pandzic, I.S.

Automatic Transfer Function Specification for Visual Emphasis of Coronary Artery Plaque

[meta data] [files: ]
Glasser, S.
; 
Oeltze, S.
; 
Hennemuth, A.
; 
Kubisch, C.
; 
Mahnken, A.
; 
Wilhelmsen, S.
; 
Preim, B.

Sketch-Based Interfaces and Modeling 2009 Co-Sponsored by Eurographics and ACM SIGGRAPH New Orleans, Louisiana, August 1-2, 2009

[meta data] [files: ]
Carr, Nathan
; 
Savamati, Faramarz
; 
Laviola, Joe
; 
Grimm, Cindy

A Grasping Hand, Made of Small Stones

[meta data] [files: ]
Peytavie, Adrien
; 
Galin, Eric
; 
Grosjean, Jerome
; 
Merillou, Stephane

BibTeX (29-Issue 1)
                
@article{
10.1111:j.1467-8659.2010.01592.x,

journal = {Computer Graphics Forum},
title = {{
Editorial}},

author = {
Scopigno, Roberto
 and 
Groeller, Eduard
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2010.01592.x}

}
                
@article{
10.1111:j.1467-8659.2009.01543.x,

journal = {Computer Graphics Forum},
title = {{
Simplifying Character Skins with Analytic Error Metrics}},

author = {
Merry, B.
 and 
Marais, P.
 and 
Gain, J.
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01543.x}

}
                
@article{
10.1111:j.1467-8659.2009.01588.x,

journal = {Computer Graphics Forum},
title = {{
Afrigraph: The African Computer Graphics Association and its Activities}},

author = {
Gain, J.
 and 
Strasser, W.
 and 
Hardy, A.
 and 
Marais, P.
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01588.x}

}
                
@article{
10.1111:j.1467-8659.2009.01538.x,

journal = {Computer Graphics Forum},
title = {{
Evaluation of an Augmented Reality Supported Picking System Under Practical Conditions}},

author = {
Reif, R.
 and 
Guenthner, W. A.
 and 
Schwerdtfeger, B.
 and 
Klinker, G.
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01538.x}

}
                
@article{
10.1111:j.1467-8659.2009.01536.x,

journal = {Computer Graphics Forum},
title = {{
Meshless Shape and Motion Design for Multiple Deformable Objects}},

author = {
Adams, B.
 and 
Wicke, M.
 and 
Ovsjanikov, M.
 and 
Wand, M.
 and 
Seidel, H.-P.
 and 
Guibas, L. J.
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01536.x}

}
                
@article{
10.1111:j.1467-8659.2009.01535.x,

journal = {Computer Graphics Forum},
title = {{
Modelling the Appearance and Behaviour of Urban Spaces}},

author = {
Vanegas, C. A.
 and 
Aliaga, D. G.
 and 
Wonka, P.
 and 
Mueller, P.
 and 
Waddell, P.
 and 
Watson, B.
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01535.x}

}
                
@article{
10.1111:j.1467-8659.2009.01546.x,

journal = {Computer Graphics Forum},
title = {{
Time-Dependent 2-D Vector Field Topology: An Approach Inspired by Lagrangian Coherent Structures}},

author = {
Sadlo, F.
 and 
Weiskopf, D.
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01546.x}

}
                
@article{
10.1111:j.1467-8659.2009.01545.x,

journal = {Computer Graphics Forum},
title = {{
Hybrid Booleans}},

author = {
Pavic, Darko
 and 
Campen, Marcel
 and 
Kobbelt, Leif
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01545.x}

}
                
@article{
10.1111:j.1467-8659.2009.01544.x,

journal = {Computer Graphics Forum},
title = {{
Fast Gauss Bilateral Filtering}},

author = {
Yoshizawa, Shin
 and 
Belyaev, Alexander
 and 
Yokota, Hideo
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01544.x}

}
                
@article{
10.1111:j.1467-8659.2009.01547.x,

journal = {Computer Graphics Forum},
title = {{
SPC: Fast and Efficient Scalable Predictive Coding of Animated Meshes}},

author = {
Stefanoski, Nikolce
 and 
Ostermann, Joern
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01547.x}

}
                
@article{
10.1111:j.1467-8659.2009.01582.x,

journal = {Computer Graphics Forum},
title = {{
Embedded Implicit Stand-Ins for Animated Meshes: A Case of Hybrid Modelling}},

author = {
Kravtsov, D.
 and 
Fryazinov, O.
 and 
Adzhiev, V.
 and 
Pasko, A.
 and 
Comninos, P.
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01582.x}

}
                
@article{
10.1111:j.1467-8659.2009.01581.x,

journal = {Computer Graphics Forum},
title = {{
Adaptive and Feature-Preserving Subdivision for High-Quality Tetrahedral Meshes}},

author = {
Burkhart, D.
 and 
Hamann, B.
 and 
Umlauf, G.
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01581.x}

}
                
@article{
10.1111:j.1467-8659.2009.01584.x,

journal = {Computer Graphics Forum},
title = {{
Constrained Texture Mapping using Image Warping}},

author = {
Seo, H.
 and 
Cordier, F.
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01584.x}

}
                
@article{
10.1111:j.1467-8659.2009.01583.x,

journal = {Computer Graphics Forum},
title = {{
Time-of-Flight Cameras in Computer Graphics}},

author = {
Kolb, A.
 and 
Barth, E.
 and 
Koch, R.
 and 
Larsen, R.
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01583.x}

}
                
@article{
10.1111:j.1467-8659.2009.01587.x,

journal = {Computer Graphics Forum},
title = {{
Multi-Perspective Modelling, Rendering and Imaging}},

author = {
Yu, J.
 and 
McMillan, L.
 and 
Sturm, P.
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01587.x}

}
                
@article{
10.1111:j.1467-8659.2009.01585.x,

journal = {Computer Graphics Forum},
title = {{
Bidirectional Texture Function Compression Based on Multi-Level Vector Quantization}},

author = {
Havran, V.
 and 
Filip, J.
 and 
Myszkowski, K.
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01585.x}

}
                
@article{
10.1111:j.1467-8659.2009.01589.x,

journal = {Computer Graphics Forum},
title = {{
Eurographics 2009 Workshop on 3D Object Retrieval (EG 3DOR 09) in Cooperation with ACM SIGGRAPH Munich, Germany March 29, 2009}},

author = {
Pratikakis, Ioannis
 and 
Spagnuolo, Michela
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01589.x}

}
                
@article{
10.1111:j.1467-8659.2009.01591.x,

journal = {Computer Graphics Forum},
title = {{
State of the Art in Example-Based Motion Synthesis for Virtual Characters in Interactive Applications}},

author = {
Pejsa, T.
 and 
Pandzic, I.S.
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01591.x}

}
                
@article{
10.1111:j.1467-8659.2009.01590.x,

journal = {Computer Graphics Forum},
title = {{
Automatic Transfer Function Specification for Visual Emphasis of Coronary Artery Plaque}},

author = {
Glasser, S.
 and 
Oeltze, S.
 and 
Hennemuth, A.
 and 
Kubisch, C.
 and 
Mahnken, A.
 and 
Wilhelmsen, S.
 and 
Preim, B.
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01590.x}

}
                
@article{
10.1111:j.1467-8659.2009.01586.x,

journal = {Computer Graphics Forum},
title = {{
Sketch-Based Interfaces and Modeling 2009 Co-Sponsored by Eurographics and ACM SIGGRAPH New Orleans, Louisiana, August 1-2, 2009}},

author = {
Carr, Nathan
 and 
Savamati, Faramarz
 and 
Laviola, Joe
 and 
Grimm, Cindy
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01586.x}

}
                
@article{
10.1111:j.1467-8659.2010.01593.x,

journal = {Computer Graphics Forum},
title = {{
A Grasping Hand, Made of Small Stones}},

author = {
Peytavie, Adrien
 and 
Galin, Eric
 and 
Grosjean, Jerome
 and 
Merillou, Stephane
},
year = {
2010},

publisher = {
The Eurographics Association and Blackwell Publishing Ltd},


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2010.01593.x}

}

Browse

Recent Submissions

Now showing 1 - 21 of 21
  • No Thumbnail Available
    Item
    Editorial
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Scopigno, Roberto; Groeller, Eduard
  • No Thumbnail Available
    Item
    Simplifying Character Skins with Analytic Error Metrics
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Merry, B.; Marais, P.; Gain, J.
    Traditionally, levels of detail (LOD) for animated characters are computed from a single pose. Later techniques refined this approach by considering a set of sample poses and evaluating a more representative error metric. A recent approach to the character animation problem, animation space, (AS) provides a framework for measuring error analytically. The work presented here uses the animation-space framework to derive two new techniques to improve the quality of LOD approximations.First, we use an animation-space distance metric within a progressive mesh-based LOD scheme, giving results that are reasonable across a range of poses, without requiring that the pose space be sampled.Second, we simplify individual vertices by reducing the number of bones that influence them, using a constrained least-squares optimization. This influence simplification is combined with the progressive mesh to form a single stream of simplifications. Influence simplification reduces the geometric error by up to an order of magnitude, and allows models to be simplified further than is possible with only a progressive mesh.Quantitative (geometric error metrics) and qualititative (user perceptual) experiments confirm that these new extensions provide significant improvements in quality over traditional, naive simplification; and while there is naturally some impact on the speed of the off-line simplification process, it is not prohibitive.
  • No Thumbnail Available
    Item
    Afrigraph: The African Computer Graphics Association and its Activities
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Gain, J.; Strasser, W.; Hardy, A.; Marais, P.
  • No Thumbnail Available
    Item
    Evaluation of an Augmented Reality Supported Picking System Under Practical Conditions
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Reif, R.; Guenthner, W. A.; Schwerdtfeger, B.; Klinker, G.
    Order picking is one of the most important process steps in logistics. Because of their flexibility, human beings cannot be replaced by machines. But if workers, in order, picking systems are equipped with a head-mounted display, Augmented Reality can improve the information visualization. In this paper, the development of such a system-called Pick-by-Vision-is presented. The system is evaluated in a user study performed in a real storage environment. Important logistics figures as well as the subjective strain were measured. The results show that a Pick-by-Vision system can considerably improve industrial order picking processes.
  • No Thumbnail Available
    Item
    Meshless Shape and Motion Design for Multiple Deformable Objects
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Adams, B.; Wicke, M.; Ovsjanikov, M.; Wand, M.; Seidel, H.-P.; Guibas, L. J.
    We present physically based algorithms for interactive deformable shape and motion modelling. We coarsely sample the objects with simulation nodes, and apply a meshless finite element method to obtain realistic deformations at interactive frame rates. This shape deformation algorithm is then used to specify keyframe poses and a smooth interpolating motion is obtained by solving for an energy-minimizing trajectory. We show how to handle collisions between different deformable objects as well as with static or moving scene objects. Secondary motion is added as a post-process by running a meshless elastic solid simulation. We enforce precomputed trajectories using control forces computed using shape matching. Key to the efficiency of our method is a sparse deformation representation and an adaptive optimization algorithm that automatically introduces new degrees of freedom in problematic regions. An accurate temporal interpolation scheme that exactly recovers rigid motions keeps the number of unknowns low and achieves realistic deformations with very few keyframes. We also show how the algorithm allows combining purely physical simulation with keyframe-based scripted animation. The presented results illustrate that our framework can handle complex shapes at interactive rates, making it a valuable tool for animators to realistically model deformable 3D shapes and their motion.
  • No Thumbnail Available
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    Modelling the Appearance and Behaviour of Urban Spaces
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Vanegas, C. A.; Aliaga, D. G.; Wonka, P.; Mueller, P.; Waddell, P.; Watson, B.
    Urban spaces consist of a complex collection of buildings, parcels, blocks and neighbourhoods interconnected by streets. Accurately modelling both the appearance and the behaviour of dense urban spaces is a significant challenge. The recent surge in urban data and its availability via the Internet has fomented a significant amount of research in computer graphics and in a number of applications in urban planning, emergency management and visualization. In this paper, we seek to provide an overview of methods spanning computer graphics and related fields involved in this goal. Our paper reports the most prominent methods in urban modelling and rendering, urban visualization and urban simulation models. A reader will be well versed in the key problems and current solution methods.
  • No Thumbnail Available
    Item
    Time-Dependent 2-D Vector Field Topology: An Approach Inspired by Lagrangian Coherent Structures
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Sadlo, F.; Weiskopf, D.
    This paper presents an approach to a time-dependent variant of the concept of vector field topology for 2-D vector fields. Vector field topology is defined for steady vector fields and aims at discriminating the domain of a vector field into regions of qualitatively different behaviour. The presented approach represents a generalization for saddle-type critical points and their separatrices to unsteady vector fields based on generalized streak lines, with the classical vector field topology as its special case for steady vector fields. The concept is closely related to that of Lagrangian coherent structures obtained as ridges in the finite-time Lyapunov exponent field. The proposed approach is evaluated on both 2-D time-dependent synthetic and vector fields from computational fluid dynamics.
  • No Thumbnail Available
    Item
    Hybrid Booleans
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Pavic, Darko; Campen, Marcel; Kobbelt, Leif
    In this paper, we present a novel method to compute Boolean operations on polygonal meshes. Given a Boolean expression over an arbitrary number of input meshes we reliably and efficiently compute an output mesh which faithfully preserves the existing sharp features and precisely reconstructs the new features appearing along the intersections of the input meshes. The term hybrid applies to our method in two ways: First, our algorithm operates on a hybrid data structure which stores the original input polygons (surface data) in an adaptively refined octree (volume data). By this we combine the robustness of volumetric techniques with the accuracy of surface-oriented techniques. Second, we generate a new triangulation only in a close vicinity around the intersections of the input meshes and thus preserve as much of the original mesh structure as possible (hybrid mesh). Since the actual processing of the Boolean operation is confined to a very small region around the intersections of the input meshes, we can achieve very high adaptive refinement resolutions and hence very high precision. We demonstrate our method on a number of challenging examples.
  • No Thumbnail Available
    Item
    Fast Gauss Bilateral Filtering
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Yoshizawa, Shin; Belyaev, Alexander; Yokota, Hideo
    In spite of high computational complexity, the bilateral filter and its modifications and extensions have recently become very popular image and shape processing tools. In this paper, we propose a fast and accurate approximation of the bilateral filter. Our approach combines a dimension elevation trick with a Fast Gauss Transform. First we represent the bilateral filter as a convolution in a high dimensional space. Then the convolution is efficiently approximated by using space partitioning and Gaussian function expansions. Advantages of our approach include linear computational complexity, user-specified precision, and an ability to process high dimensional and non-uniformly sampled data. We demonstrate capabilities of the approach by considering its applications to the image and volume denoising and high-dynamic-range tone mapping problems.
  • No Thumbnail Available
    Item
    SPC: Fast and Efficient Scalable Predictive Coding of Animated Meshes
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Stefanoski, Nikolce; Ostermann, Joern
  • No Thumbnail Available
    Item
    Embedded Implicit Stand-Ins for Animated Meshes: A Case of Hybrid Modelling
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Kravtsov, D.; Fryazinov, O.; Adzhiev, V.; Pasko, A.; Comninos, P.
    In this paper, we address shape modelling problems, encountered in computer animation and computer games development that are difficult to solve just using polygonal meshes. Our approach is based on a hybrid-modelling concept that combines polygonal meshes with implicit surfaces. A hybrid model consists of an animated polygonal mesh and an approximation of this mesh by a convolution surface stand-in that is embedded within it or is attached to it. The motions of both objects are synchronised using a rigging skeleton. We model the interaction between an animated mesh object and a viscoelastic substance, which is normally represented in an implicit form. Our approach is aimed at achieving verisimilitude rather than physically based simulation. The adhesive behaviour of the viscous object is modelled using geometric blending operations on the corresponding implicit surfaces. Another application of this approach is the creation of metamorphosing implicit surface parts that are attached to an animated mesh. A prototype implementation of the proposed approach and several examples of modelling and animation with near real-time preview times are presented.
  • No Thumbnail Available
    Item
    Adaptive and Feature-Preserving Subdivision for High-Quality Tetrahedral Meshes
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Burkhart, D.; Hamann, B.; Umlauf, G.
    We present an adaptive subdivision scheme for unstructured tetrahedral meshes inspired by the -subdivision scheme for triangular meshes. Existing tetrahedral subdivision schemes do not support adaptive refinement and have traditionally been driven by the need to generate smooth three-dimensional deformations of solids. These schemes use edge bisections to subdivide tetrahedra, which generates octahedra in addition to tetrahedra. To split octahedra into tetrahedra one routinely chooses a direction for the diagonals for the subdivision step. We propose a new topology-based refinement operator that generates only tetrahedra and supports adaptive refinement. Our tetrahedral subdivision algorithm is motivated by the need to have one representation for the modeling, the simulation and the visualization and so to bridge the gap between CAD and CAE. Our subdivision algorithm design emphasizes on geometric quality of the tetrahedral meshes, local and adaptive refinement operations, and preservation of sharp geometric features on the boundary and in the interior of the physical domain.
  • No Thumbnail Available
    Item
    Constrained Texture Mapping using Image Warping
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Seo, H.; Cordier, F.
    We introduce in this paper a new method for smooth foldover-free warping of images. It allows users to specify the constraints in two different ways: positional constraints to constrain the position of points in the image and gradient constraints to constrain the orientation and scaling of some parts of the image. We then show how our method is used for texture mapping with hard constraints. We start with an unconstrained planar embedding of the target mesh calculated with conventional methods. In order to obtain a mapping that satisfies the user-defined constraints, we use our warping method to align the features of the texture image with those of the unconstrained embedding. Compared to previous work, our method generates a smoother texture mapping and offers higher level of control for defining the constraints.
  • No Thumbnail Available
    Item
    Time-of-Flight Cameras in Computer Graphics
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Kolb, A.; Barth, E.; Koch, R.; Larsen, R.
    A growing number of applications depend on accurate and fast 3D scene analysis. Examples are model and lightfield acquisition, collision prevention, mixed reality and gesture recognition. The estimation of a range map by image analysis or laser scan techniques is still a time-consuming and expensive part of such systems.A lower-priced, fast and robust alternative for distance measurements are time-of-flight (ToF) cameras. Recently, significant advances have been made in producing low-cost and compact ToF devices, which have the potential to revolutionize many fields of research, including computer graphics, computer vision and human machine interaction (HMI).These technologies are starting to have an impact on research and commercial applications. The upcoming generation of ToF sensors, however, will be even more powerful and will have the potential to become ubiquitous real-time geometry devices for gaming, web-conferencing, and numerous other applications. This paper gives an account of recent developments in ToF technology and discusses the current state of the integration of this technology into various graphics-related applications.
  • No Thumbnail Available
    Item
    Multi-Perspective Modelling, Rendering and Imaging
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Yu, J.; McMillan, L.; Sturm, P.
    A perspective image represents the spatial relationships of objects in a scene as they appear from a single viewpoint. In contrast, a multi-perspective image combines what is seen from several viewpoints into a single image. Despite their incongruity of view, effective multi-perspective images are able to preserve spatial coherence and can depict, within a single context, details of a scene that are simultaneously inaccessible from a single view, yet easily interpretable by a viewer. In computer vision, multi-perspective images have been used for analysing structure revealed via motion and generating panoramic images with a wide field-of-view using mirrors.In this STAR, we provide a practical guide on topics in multi-perspective modelling and rendering methods and multi-perspective imaging systems. We start with a brief review of multi-perspective image techniques frequently employed by artists such as the visual paradoxes of Escher, the Cubism of Picasso and Braque and multi-perspective panoramas in cel animations. We then characterize existing multi-perspective camera models, with an emphasis on their underlying geometry and image properties. We demonstrate how to use these camera models for creating specific multi-perspective rendering effects. Furthermore, we show that many of these cameras satisfy the multi-perspective stereo constraints and we demonstrate several multi-perspective imaging systems for extracting 3D geometry for computer vision.The participants learn about topics in multi-perspective modelling and rendering for generating compelling pictures for computer graphics and in multi-perspective imaging for extracting 3D geometry for computer vision. We hope to provide enough fundamentals to satisfy the technical specialist without intimidating curious digital artists interested in multi-perspective images.The intended audience includes digital artists, photographers and computer graphics and computer vision researchers using or building multi-perspective cameras. They will learn about multi-perspective modelling and rendering, along with many real world multi-perspective imaging systems.
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    Bidirectional Texture Function Compression Based on Multi-Level Vector Quantization
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Havran, V.; Filip, J.; Myszkowski, K.
    The Bidirectional Texture Function (BTF) is becoming widely used for accurate representation of real-world material appearance. In this paper a novel BTF compression model is proposed. The model resamples input BTF data into a parametrization, allowing decomposition of individual view and illumination dependent texels into a set of multi-dimensional conditional probability density functions. These functions are compressed in turn using a novel multi-level vector quantization algorithm. The result of this algorithm is a set of index and scale code-books for individual dimensions. BTF reconstruction from the model is then based on fast chained indexing into the nested stored code-books. In the proposed model, luminance and chromaticity are treated separately to achieve further compression. The proposed model achieves low distortion and compression ratios 1:233-1:2040, depending on BTF sample variability. These results compare well with several other BTF compression methods with predefined compression ratios, usually smaller than 1:200. We carried out a psychophysical experiment comparing our method with LPCA method. BTF synthesis from the model was implemented on a standard GPU, yielded interactive framerates. The proposed method allows the fast importance sampling required by eye-path tracing algorithms in image synthesis.
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    Eurographics 2009 Workshop on 3D Object Retrieval (EG 3DOR 09) in Cooperation with ACM SIGGRAPH Munich, Germany March 29, 2009
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Pratikakis, Ioannis; Spagnuolo, Michela
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    State of the Art in Example-Based Motion Synthesis for Virtual Characters in Interactive Applications
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Pejsa, T.; Pandzic, I.S.
    Animated virtual human characters are a common feature in interactive graphical applications, such as computer and video games, online virtual worlds and simulations. Due to dynamic nature of such applications, character animation must be responsive and controllable in addition to looking as realistic and natural as possible. Though procedural and physics-based animation provide a great amount of control over motion, they still look too unnatural to be of use in all but a few specific scenarios, which is why interactive applications nowadays still rely mainly on recorded and hand-crafted motion clips. The challenge faced by animation system designers is to dynamically synthesize new, controllable motion by concatenating short motion segments into sequences of different actions or by parametrically blending clips that correspond to different variants of the same logical action. In this article, we provide an overview of research in the field of example-based motion synthesis for interactive applications. We present methods for automated creation of supporting data structures for motion synthesis and describe how they can be employed at run-time to generate motion that accurately accomplishes tasks specified by the AI or human user.
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    Automatic Transfer Function Specification for Visual Emphasis of Coronary Artery Plaque
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Glasser, S.; Oeltze, S.; Hennemuth, A.; Kubisch, C.; Mahnken, A.; Wilhelmsen, S.; Preim, B.
    Cardiovascular imaging with current multislice spiral computed tomography (MSCT) technology enables a non-invasive evaluation of the coronary arteries. Contrast-enhanced MSCT angiography with high spatial resolution allows for a segmentation of the coronary artery tree. We present an automatically adapted transfer function (TF) specification to highlight pathologic changes of the vessel wall based on the segmentation result of the coronary artery tree. The TFs are combined with common visualization techniques, such as multiplanar reformation and direct volume rendering for the evaluation of coronary arteries in MSCT image data. The presented TF-based mapping of CT values in Hounsfield Units (HU) to color and opacity leads to a different color coding for different plaque types. To account for varying HU values of the vessel lumen caused by the contrast medium, the TFs are adapted to each dataset by local histogram analysis. We describe an informal evaluation with three board-certified radiologists which indicates that the represented visualizations guide the user s attention to pathologic changes of the vessel wall as well as provide an overview about spatial variations.
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    Sketch-Based Interfaces and Modeling 2009 Co-Sponsored by Eurographics and ACM SIGGRAPH New Orleans, Louisiana, August 1-2, 2009
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Carr, Nathan; Savamati, Faramarz; Laviola, Joe; Grimm, Cindy
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    A Grasping Hand, Made of Small Stones
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Peytavie, Adrien; Galin, Eric; Grosjean, Jerome; Merillou, Stephane