Short Papers

Permanent URI for this collection

https://diglib.eg.org/handle/10.2312/286

Feature-Based Mesh Editing

[meta data] [files:
001-004.pdf ,
addonfigures.pdf
]
Zhou, Qingnan
; 
Weinkauf, Tino
; 
Sorkine, Olga

Collision-Driven Volumetric Deformation on the GPU

[meta data] [files:
009-012.pdf
]
Aldrich, Garrett
; 
Pinskiy, Dmitriy
; 
Hamann, Bernd

Volumetric plastic deformation

[meta data] [files:
005-008.pdf ,
deformed-clay.png ,
interaction.avi ,
metal.png ,
modelador1.png
]
Prados, Francisco J. R.
; 
Salas, Alejandro J. León
; 
Torres, Juan Carlos

Efficient Feature-preserving Local Projection Operator for Geometry Reconstruction

[meta data] [files:
013-016.pdf
]
Liao, Bin
; 
Xiao, Chunxia
; 
Jin, Liqiang

Reconstructing Buildings as Textured Low Poly Meshes from Point Clouds and Images

[meta data] [files:
017-020.pdf ,
library.wmv ,
octagon.wmv
]
Reisner-Kollmann, Irene
; 
Luksch, Christian
; 
Schwärzler, Michael

Folded Paper Geometry from 2D Pattern and 3D Contour

[meta data] [files:
021-024.pdf ,
movie.mp4
]
Rohmer, Damien
; 
Cani, Marie-Paule
; 
Hahmann, Stefanie
; 
Thibert, Boris

An Error Bound for Decoupled Visibility with Application to Relighting

[meta data] [files:
025-028.pdf ,
supplemental.zip
]
Schwenk, Karsten
; 
Fellner, Dieter W.

Realistic Simulation of Peripheral Vision Using An Aspherical Eye Model

[meta data] [files:
037-040.pdf
]
Wu, Jiaze
; 
Zheng, Changwen
; 
Hu, Xiaohui
; 
Xu, Fanjiang

Improving Shadow Map Filtering with Statistical Analysis

[meta data] [files:
033-036.pdf
]
Gumbau, Jesus
; 
Szirmay-Kalos, László
; 
Sbert, Mateu
; 
Sellés, Miguel Chover

Separable Approximation of Ambient Occlusion

[meta data] [files:
029-032.pdf ,
supplementary.zip
]
Huang, Jing
; 
Boubekeur, Tamy
; 
Ritschel, Tobias
; 
Holländer, Matthias
; 
Eisemann, Elmar

Warp-based Motion Compensation for Endoscopic Kymography

[meta data] [files:
041-044.pdf ,
eg2011-schneideretal-kymography.m4v
]
Schneider, David C.
; 
Hilsmann, Anna
; 
Eisert, Peter

Skimming Video Action Using Annotated 3D Surfaces

[meta data] [files:
049-052.pdf
]
Falchuk, Ben
; 
Wu, Chung-Ying
; 
El-Gaaly, Tarek
; 
Vashist, Akshay

Motion Capture Data Completion and Denoising by Singular Value Thresholding

[meta data] [files:
045-048.pdf ,
all.mov
]
Lai, Ranch Y. Q.
; 
Yuen, Pong C.
; 
Lee, Kelvin K. W.

Automatic Stream Surface Seeding

[meta data] [files:
053-056.pdf ,
short2049.mp4
]
Edmunds, Matt
; 
McLoughlin, Tony
; 
Laramee, Robert S.
; 
Chen, Guoning
; 
Zhang, Eugene
; 
Max, Nelson

Fast Hydraulic and Thermal Erosion on GPU

[meta data] [files:
057-060.pdf ,
screenshot105.jpg ,
screenshot151.jpg ,
screenshot219.jpg ,
screenshot234.jpg
]
Jákó, Balázs
; 
Tóth, Balázs

Enhancing Image-Based Aging Approaches

[meta data] [files:
069-072.pdf
]
Clément, Olivier
; 
Paquette, Eric

Alpha Compression with Variable Data Formats

[meta data] [files:
065-068.pdf ,
short2003_dxt5acwaveform.jpg ,
short2003_eacwaveform.jpg ,
short2003_pic.jpg
]
Jiang, Yifei
; 
Gui, Mindan
; 
Chen, Shuai
; 
Hu, Weiwu

Crystal Scattering Simulation for PET on the GPU

[meta data] [files:
061-064.pdf
]
Magdics, Milán
; 
Szirmay-Kalos, László

BibTeX (Short Papers)
@inproceedings{
:10.2312/EG2011/short/001-004,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Feature-Based Mesh Editing}},

author = {
Zhou, Qingnan
 and 
Weinkauf, Tino
 and 
Sorkine, Olga
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/001-004}

}
@inproceedings{
:10.2312/EG2011/short/009-012,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Collision-Driven Volumetric Deformation on the GPU}},

author = {
Aldrich, Garrett
 and 
Pinskiy, Dmitriy
 and 
Hamann, Bernd
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/009-012}

}
@inproceedings{
:10.2312/EG2011/short/005-008,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Volumetric plastic deformation}},

author = {
Prados, Francisco J. R.
 and 
Salas, Alejandro J. León
 and 
Torres, Juan Carlos
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/005-008}

}
@inproceedings{
:10.2312/EG2011/short/013-016,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Efficient Feature-preserving Local Projection Operator for Geometry Reconstruction}},

author = {
Liao, Bin
 and 
Xiao, Chunxia
 and 
Jin, Liqiang
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/013-016}

}
@inproceedings{
:10.2312/EG2011/short/017-020,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Reconstructing Buildings as Textured Low Poly Meshes from Point Clouds and Images}},

author = {
Reisner-Kollmann, Irene
 and 
Luksch, Christian
 and 
Schwärzler, Michael
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/017-020}

}
@inproceedings{
:10.2312/EG2011/short/021-024,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Folded Paper Geometry from 2D Pattern and 3D Contour}},

author = {
Rohmer, Damien
 and 
Cani, Marie-Paule
 and 
Hahmann, Stefanie
 and 
Thibert, Boris
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/021-024}

}
@inproceedings{
:10.2312/EG2011/short/025-028,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
An Error Bound for Decoupled Visibility with Application to Relighting}},

author = {
Schwenk, Karsten
 and 
Fellner, Dieter W.
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/025-028}

}
@inproceedings{
:10.2312/EG2011/short/037-040,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Realistic Simulation of Peripheral Vision Using An Aspherical Eye Model}},

author = {
Wu, Jiaze
 and 
Zheng, Changwen
 and 
Hu, Xiaohui
 and 
Xu, Fanjiang
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/037-040}

}
@inproceedings{
:10.2312/EG2011/short/033-036,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Improving Shadow Map Filtering with Statistical Analysis}},

author = {
Gumbau, Jesus
 and 
Szirmay-Kalos, László
 and 
Sbert, Mateu
 and 
Sellés, Miguel Chover
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/033-036}

}
@inproceedings{
:10.2312/EG2011/short/029-032,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Separable Approximation of Ambient Occlusion}},

author = {
Huang, Jing
 and 
Boubekeur, Tamy
 and 
Ritschel, Tobias
 and 
Holländer, Matthias
 and 
Eisemann, Elmar
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/029-032}

}
@inproceedings{
:10.2312/EG2011/short/041-044,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Warp-based Motion Compensation for Endoscopic Kymography}},

author = {
Schneider, David C.
 and 
Hilsmann, Anna
 and 
Eisert, Peter
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/041-044}

}
@inproceedings{
:10.2312/EG2011/short/049-052,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Skimming Video Action Using Annotated 3D Surfaces}},

author = {
Falchuk, Ben
 and 
Wu, Chung-Ying
 and 
El-Gaaly, Tarek
 and 
Vashist, Akshay
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/049-052}

}
@inproceedings{
:10.2312/EG2011/short/045-048,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Motion Capture Data Completion and Denoising by Singular Value Thresholding}},

author = {
Lai, Ranch Y. Q.
 and 
Yuen, Pong C.
 and 
Lee, Kelvin K. W.
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/045-048}

}
@inproceedings{
:10.2312/EG2011/short/053-056,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Automatic Stream Surface Seeding}},

author = {
Edmunds, Matt
 and 
McLoughlin, Tony
 and 
Laramee, Robert S.
 and 
Chen, Guoning
 and 
Zhang, Eugene
 and 
Max, Nelson
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/053-056}

}
@inproceedings{
:10.2312/EG2011/short/057-060,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Fast Hydraulic and Thermal Erosion on GPU}},

author = {
Jákó, Balázs
 and 
Tóth, Balázs
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/057-060}

}
@inproceedings{
:10.2312/EG2011/short/069-072,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Enhancing Image-Based Aging Approaches}},

author = {
Clément, Olivier
 and 
Paquette, Eric
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/069-072}

}
@inproceedings{
:10.2312/EG2011/short/065-068,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Alpha Compression with Variable Data Formats}},

author = {
Jiang, Yifei
 and 
Gui, Mindan
 and 
Chen, Shuai
 and 
Hu, Weiwu
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/065-068}

}
@inproceedings{
:10.2312/EG2011/short/061-064,

booktitle = {
Eurographics 2011 - Short Papers},

editor = {
N. Avis and S. Lefebvre
},
title = {{
Crystal Scattering Simulation for PET on the GPU}},

author = {
Magdics, Milán
 and 
Szirmay-Kalos, László
},
year = {
2011},

publisher = {
The Eurographics Association},


ISSN = {1017-4656},

DOI = {
/10.2312/EG2011/short/061-064}

}

Browse

Recent Submissions

Now showing 1 - 18 of 18
  • Thumbnail Image
    Item
    Feature-Based Mesh Editing
    (The Eurographics Association, 2011) Zhou, Qingnan; Weinkauf, Tino; Sorkine, Olga; N. Avis and S. Lefebvre
    Editing and deformation of irregular meshes have become standard tools in geometric modeling. Most approaches try to preserve low-level differential properties of the surface during editing, whereas the global structure and shape of the features are not explicitly taken into account. In this paper, we introduce a feature-driven editing approach that puts global structural properties of the shape into the center of attention. We start by segmenting the mesh by ridges and valleys and use the so-defined curves and surface regions as intuitive handles for all subsequent editing operations. Our framework supports manipulations the positions and curvature values of the handles and the various mesh regions. In order to preserve the existing features, prevent unwanted appearance of new features, and maintain or manipulate global aspects of the shape, we apply curvature optimization in the affected areas. We show that the combination of feature extraction and curvature optimization leads to an intuitive modeling tool for high-quality surface manipulation.
  • Thumbnail Image
    Item
    Collision-Driven Volumetric Deformation on the GPU
    (The Eurographics Association, 2011) Aldrich, Garrett; Pinskiy, Dmitriy; Hamann, Bernd; N. Avis and S. Lefebvre
    We present a novel parallel algorithm to animate the deformation of a soft body in response to collision. Our algorithm incorporates elements of physically-based methods, and at the same time, it allows artistic control of general deformation behavior. Our solver has important benefits for practical use, such as evaluation of animation frames in an arbitrary order, effective approximation of volume preservation, and stability under large deformations. To deform production-complexity data at interactive rates, we leverage the computational power of modern GPUs. In our solution we propose a specialized, CUDA-based framework for the efficient access and update of mesh structures.
  • Thumbnail Image
    Item
    Volumetric plastic deformation
    (The Eurographics Association, 2011) Prados, Francisco J. R.; Salas, Alejandro J. León; Torres, Juan Carlos; N. Avis and S. Lefebvre
    Working with volumetric information is always challenging. Displaying, processing or modifying volumes requires in most cases processing a considerable part of them, if not the whole structure. Such delays might be inconvenient for applications which require fast or smooth interaction, like realistic rendering or virtual sculpting. This paper focuses on the volume sculpting paradigm. Making use of a haptic device for interaction, the solution presented here provides a smooth and physically correct force feedback. The deformation algorithm is designed to provide a fast visual response. Additionally, this method is able to operate with large volumes, since it was designed to create a progressive, and therefore, scalable simulation.
  • Thumbnail Image
    Item
    Efficient Feature-preserving Local Projection Operator for Geometry Reconstruction
    (The Eurographics Association, 2011) Liao, Bin; Xiao, Chunxia; Jin, Liqiang; N. Avis and S. Lefebvre
    This paper proposes an efficient and feature-preserving locally optimal projection operator (FLOP) for geometry reconstruction. We first develop a bilateral weighted local optimal projection operator. We then present a novel fast FLOP operator based on random sampling of Kernel Density Estimate (KDE), which greatly accelerates FLOP. The experimental results show that the proposed algorithms are efficient and robust for feature-preserving geometry reconstruction.
  • Thumbnail Image
    Item
    Reconstructing Buildings as Textured Low Poly Meshes from Point Clouds and Images
    (The Eurographics Association, 2011) Reisner-Kollmann, Irene; Luksch, Christian; Schwärzler, Michael; N. Avis and S. Lefebvre
    Current urban building reconstruction techniques rely mainly on data gathered from either laser scans or image- based approaches, and do usually require a large amount of manual post-processing and modeling. Difficulties arise due to erroneous and noisy data, and due to the huge amount of information to process. We propose a system that helps to overcome these time-consuming steps by automatically generating low-poly 3D building models. This is achieved by taking both information from point clouds and image information into account, exploiting the particular strengths and avoiding the relative weaknesses of these data sources: While the segmented point cloud is used to identify the dominant planar surfaces in 3D space, the images are used to extract accurate edges, fill holes and generate textured polygonal meshes of urban buildings.
  • Thumbnail Image
    Item
    Folded Paper Geometry from 2D Pattern and 3D Contour
    (The Eurographics Association, 2011) Rohmer, Damien; Cani, Marie-Paule; Hahmann, Stefanie; Thibert, Boris; N. Avis and S. Lefebvre
    Folded paper exhibits very characteristic shapes, due to the presence of sharp folds and to exact isometry with a given planar pattern. Therefore, none of the physically-based simulators developed so far can handle paper-like material. We propose a purely geometric solution to generate static folded paper geometry from a 2D pattern and a 3D placement of its contour curve. Fold lines are explicitly identified and used to control a recursive, local sub- division process, leading to an efficient procedural modeling of the surface through a fold-aligned mesh. Contrary to previous work, our method generates paper-like surfaces with sharp creases while maintaining approximate isometry with the input pattern.
  • Thumbnail Image
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    An Error Bound for Decoupled Visibility with Application to Relighting
    (The Eurographics Association, 2011) Schwenk, Karsten; Fellner, Dieter W.; N. Avis and S. Lefebvre
    Monte Carlo estimation of direct lighting is often dominated by visibility queries. If an error is tolerable, the calculations can be sped up by using a simple scalar occlusion factor per light source to attenuate radiance, thus decoupling the expensive estimation of visibility from the comparatively cheap sampling of unshadowed radiance and BRDF. In this paper we analyze the error associated with this approximation and derive an upper bound. We demonstrate in a simple relighting application how our result can be used to reduce noise by introducing a controlled error if a reliable estimate of the visibility is already available.
  • Thumbnail Image
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    Realistic Simulation of Peripheral Vision Using An Aspherical Eye Model
    (The Eurographics Association, 2011) Wu, Jiaze; Zheng, Changwen; Hu, Xiaohui; Xu, Fanjiang; N. Avis and S. Lefebvre
    A novel method is proposed to accurately simulate the peripheral vision under different visual perception. An accurate aspherical schematic eye model is firstly introduced to reasonably predict the anatomical and optical properties of the human eye. This eye model is composed of the Navarro schematic eye model with aspherical surfaces as a basic model, and a corresponding accommodation model, and both these models are combined to simulate the varying refractive power of the human eye. Finally, distributed ray tracing techniques is combined with this eye model to produce a variety of visual results.
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    Improving Shadow Map Filtering with Statistical Analysis
    (The Eurographics Association, 2011) Gumbau, Jesus; Szirmay-Kalos, László; Sbert, Mateu; Sellés, Miguel Chover; N. Avis and S. Lefebvre
    Shadow maps are widely used in real-time applications. Shadow maps cannot be filtered linearly as regular textures, thus undersampling leads to severe aliasing. This problem has been attacked by methods that transform the depth values to allow approximate linear filtering and to approaches based on statistical analysis, which suffer from light bleeding artifacts. In this paper we propose a new statistical filtering method for shadow maps, which approximates the cumulative distribution function (CDF) of depths with a power function. This approximation significantly reduces light bleeding artifacts, maintaining performance and spatial costs. Like existing techniques, the algorithm is easy to implement on the graphics hardware and is fairly scalable.
  • Thumbnail Image
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    Separable Approximation of Ambient Occlusion
    (The Eurographics Association, 2011) Huang, Jing; Boubekeur, Tamy; Ritschel, Tobias; Holländer, Matthias; Eisemann, Elmar; N. Avis and S. Lefebvre
    Ambient occlusion (AO) provides an effective approximation to global illumination that enjoys widespread use amongst practitioners. In this paper, we present a fast easy-to-implement separable approximation to screen space ambient occlusion. Computing occlusion first along a single direction and then transporting this occlusion into a second pass that is stochastically evaluating the final shading based on the AO estimates proves extremely efficient. Combined with interleaved sampling and geometry-aware blur, visually convincing results close to a non-separable occlusion can be obtained at much higher performance.
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    Warp-based Motion Compensation for Endoscopic Kymography
    (The Eurographics Association, 2011) Schneider, David C.; Hilsmann, Anna; Eisert, Peter; N. Avis and S. Lefebvre
    Endoscopic videokymography is a method for visualizing the motion of the plica vocalis (vocal folds) for medical diagnosis. The diagnostic interpretability of a kymogram deteriorates if camera motion interferes with vocal fold motion, which is hard to avoid in practice. We propose an algorithm for compensating strong camera motion for videokymography. The approach is based on an image-based inverse warping scheme that can be stated as an optimization problem. The algorithm is parallelizable and real-time capable on the CPU. We discuss advantages of the image-based approach and address its use for approximate structure visualization of the endoscopic scene.
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    Skimming Video Action Using Annotated 3D Surfaces
    (The Eurographics Association, 2011) Falchuk, Ben; Wu, Chung-Ying; El-Gaaly, Tarek; Vashist, Akshay; N. Avis and S. Lefebvre
    It has become all too clear that despite the ever-growing reams of available media, we face diminishing strategic returns from it unless we craft better tools that not only let us playback media but also get us quickly to media segments of most interest. Witness the everyday frustration of false positives when watching user-generated video content that, with appropriate insight, the user might have otherwise chosen not to watch. In this paper we describe a new and dramatically different new way to both summarize and interact with multimedia information in rapid, 3D, user-in-the-loop, skimming sessions. Our new interaction technique, which can accommodate object recognition algorithms, is a fusion of media summarization and 3D scene generation techniques and runs on mobile, tablet and desktops.
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    Motion Capture Data Completion and Denoising by Singular Value Thresholding
    (The Eurographics Association, 2011) Lai, Ranch Y. Q.; Yuen, Pong C.; Lee, Kelvin K. W.; N. Avis and S. Lefebvre
    Human motion is of high articulation and correlation.When a human motion sequence is represented by a matrix, the matrix will be approximately low-rank. This low-rank property has been used by previous manifold-based approaches such as PCA and GPLVM. Encouraging results yielded by those approaches show that the low-rank property is of interest and importance for animating human motion. However, none of those approaches explicitly exploits it for motion capture data processing. In this paper, we propose to deal with motion capture data based on recently developed low-rank matrix completion theory and algorithms. Unlike previous approaches, the proposed method relies on low-rank prior instead of motion prior. To verify it effectiveness for dealing with motion capture data, we show that incomplete human motion can be effectively reconstructed. We also demonstrate that a noisecorrupted motion can be nicely recovered.
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    Automatic Stream Surface Seeding
    (The Eurographics Association, 2011) Edmunds, Matt; McLoughlin, Tony; Laramee, Robert S.; Chen, Guoning; Zhang, Eugene; Max, Nelson; N. Avis and S. Lefebvre
    The visualisation of 3D flow poses many challenges. Difficulties can stem from attempting to capture all flow features, the speed of computation, and spatial perception. Streamlines and stream surfaces are standard tools for visualising 3D flow. Although a variety of automatic seeding approaches have been proposed for streamlines, little work has been presented for stream surfaces. We present a novel automatic approach to the seeding of stream surfaces in 3D flow fields. We first describe defining seeding curves at the domain boundaries from isolines generated from a derived scalar field. We then detail the generation of stream surfaces integrated through the flow and discuss the associated challenges of surface termination and occlusion. We also present the results of this algorithm, how we achieve satisfactory domain coverage and capture the features of the flow field. Strategies for resolving occlusion resulting from seeding multiple surfaces are also presented and analysed.
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    Fast Hydraulic and Thermal Erosion on GPU
    (The Eurographics Association, 2011) Jákó, Balázs; Tóth, Balázs; N. Avis and S. Lefebvre
    Computer games, simulators and many other computer graphics applications display external scenes where a realistic looking terrain is a vital part of the view. In this paper we propose a method that generates realistic virtual terrains by simulation of hydraulic and thermal erosion on a predefined heightfield. The model is designed to be executed interactively on parallel architectures like graphics processors.
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    Enhancing Image-Based Aging Approaches
    (The Eurographics Association, 2011) Clément, Olivier; Paquette, Eric; N. Avis and S. Lefebvre
    Modern video games and computer-animated movies exhibit extremely realistic synthetic images. To achieve such a level of realism, artists have to consider several characteristics including material appearance changes from object aging such as rust, bumps, dents, or simply dust. Since adding these details is time-consuming, several approaches have been proposed to ease the aging process and reduce related costs. In this paper, we address some problems and limitations from image based aging techniques by proposing extensions intended to widen their range of application. First, we present a new automatic positioning system that handles special orientation cases, thus increasing the overall controllability on the aging framework. Also, we propose an innovative process to better handle multiple texture colorations during the synthesis phase of image-based aging techniques.
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    Alpha Compression with Variable Data Formats
    (The Eurographics Association, 2011) Jiang, Yifei; Gui, Mindan; Chen, Shuai; Hu, Weiwu; N. Avis and S. Lefebvre
    Based on the insight into the essential differences between transparency and color, we present a novel alpha compression scheme, called EAC (Enhanced Alpha Compression), as an improvement to that of DXT5. EAC defines new compression data formats, and employs clustering algorithms combined with linear interpolation method used in DXT5 to compress 16 input alpha values to 64 bits. The compressed block has three possible formats, corresponding to two process modes in decompression. Results show that EAC improves the average PSNR with about 0.2 dB compared to alpha compression of DXT5 over a set of test images. Moreover, the average cell area of hardware implementation is reduced by about 25 percent, and the power consumption is lowered by 21.66 percent 26.75 percent.
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    Crystal Scattering Simulation for PET on the GPU
    (The Eurographics Association, 2011) Magdics, Milán; Szirmay-Kalos, László; N. Avis and S. Lefebvre
    This paper presents a fast algorithm to simulate inter-crystal scattering to increase the accuracy of Positron Emission Tomography (PET). Theoretically, inter-crystal scattering computation would require the solution of a particle transport problem, which is quite time consuming. However, most of this calculation can be ported to a pre-processing phase, taking advantage of the fact that the structure of the detector is fixed. Pre-computing the scattering probabilities inside the crystals, the final system response is the convolution of the geometric response obtained with the assumption that crystals are ideal absorbers and the crystal transport probability matrix. This convolution is four-dimensional which poses complexity problems as the complexity of the naive convolution evaluation grows exponentially with the dimension of the domain. We use Monte Carlo method to attack the curse of dimension. We demonstrate that these techniques have just negligible overhead.