Short Papers 2007

Permanent URI for this collection

Frontmatter

Preface and Table of Contents

-
SP1 - Session 1

A Unified Interpolatory and Approximation sqrt-3 Subdivision Scheme

Lin, Shujin
Luo, Xiaonan
SP1 - Session 1

Shape Analysis for Augmented Topological Shape Descriptor

Symonova, Olga
Amicis, Raffaele De
SP1 - Session 1

Reeb Chart Unfolding Based 3D Shape Signatures

Tierny, Julien
Vandeborre, Jean-Philippe
Daoudi, Mohamed
SP1 - Session 1

An Accurate Implicit Field Representation for Meshes and Its Adapted Triangulation Algorithms

Fournier, Marc
Dischler, J. - M.
Bechmann, D.
SP1 - Session 1

Exact Computation of the Hausdorff Distance between Triangular Meshes

Straub, Raphael
SP1 - Session 1

View-based Shape Similarity using Mutual Information Spheres

García, Francisco González
Feixas, Miquel
Sbert, Mateu
SP1 - Session 1

Exemplar-based Worn Edges

Brachmann, Christoph
Walther-Franks, Benjamin
JörnLoviscach,
SP1 - Session 1

Stabilized Noise

Yoon, Jong-Chul
Lee, In-Kwon
SP2 - Session 2

High Speed Skin Color Detection and Localization on a GPU

Seshadrinathan, Manoj
Dempski, Kelly
SP1 - Session 1

Improved Skeleton Computation of an Encoded Volume

Ayala, Dolors
SP2 - Session 2

Volumetric Normal Mapping in Rendering of Multivariate Volume Data

Seipel, Stefan
SP2 - Session 2

Construction of Non-Blobby Surface from Particles

Harada, Takahiro
Koshizuka, Seiichi
Kawaguchi, Yoichiro
SP2 - Session 2

Enforcing Scene Constraints in Single View Reconstruction

Lourakis, Manolis
Argyros, Antonis
SP2 - Session 2

Automated Combination of Real-Time Shader Programs

Trapp, Matthias
Döller, Jürgen
SP2 - Session 2

Fast GPU-based Visibility Computation for Natural Illumination of Volume Data Sets

Ritschel, Tobias
SP2 - Session 2

Imperceptible Calibration for Radiometric Compensation

Zollmann, Stefanie
Bimber, Oliver
SP2 - Session 2

Object-Oriented Shader Design

Kuck, Roland
SP2 - Session 2

Fast Hierarchical Methods to Detect Collisions between Deformable Objects: A Comparison

Madera, Francisco
Day, A. M.
Laycock, S. D.
SP3 - Session 3

Simultaneous Visualization of Preoperative Planning Models and Intraoperative 2D Ultrasound for Liver Surgery

Hansen, Christian
Köhn, Alexander
Zidowitz, Stephan
Peitgen, Heinz-Otto
Ritter, Felix
SP3 - Session 3

Adaptive Abstraction of 3D scenes in Real-Time

Redmond, Niall
Dingliana, John
SP3 - Session 3

Painterly Effects Rendering with Focus Based Level of Detail

Levente, Kovács
Tamás, Szirányi
SP3 - Session 3

Liquid Diffusion Model that Accounts for a Variety of Dyeing Parameters

Yuki, Morimoto
Tanaka, Masayuki
Tsuruno, Reiji
Tomimatsu, Kiyoshi
SP3 - Session 3

Fast Hierarchical 3D Distance Transforms on the GPU

Cuntz, Nicolas
Kolb, Andreas
SP3 - Session 3

Real-Time 3D Lettering with a 2D Font Engine

Heise, Sebastian
Loviscach, Jörn
SP3 - Session 3

Bridging Semantic Web and Digital Shapes

Papaleo, Laura
Floriani, Leila De
Hendler, Jim
SP3 - Session 3

Spinoff - Transferring Energy between Real and Virtual Worlds

Groenegress, Christoph
Slater, Mel
Tamke, Martin
Thomsen, Mette Ramsgard
SP3 - Session 3

Pareto-Based Perceptual Metric for Imperceptible Simplification on Mobile Displays

Wu, Fan
Agu, Emmanuel
Lindsay, Clifford
SP3 - Session 3

Take a Stroll in Another World

Ruttkay, Zsofia
Orbons, Erik
SP3 - Session 3

Virtual Agent Navigation in Open Spaces using Iterative Shrinking Polygons

Haciomeroglu, Murat
Laycock, Robert
Day, Andy
Medical Prize

State-of-the-Art Computer Graphics in Neurosurgical Planning and Risk Assessment

Köhn, Alexander
Weiler, Florian
Klein, Jan
Konrad, Olaf
Hahn, Horst
Peitgen, Heinz-Otto
Medical Prize

A Pen-based Interface for Generating Graphical Reports of Findings in Cardiac Catheterization

Mori, Yuki
Igarashi, Takeo
Haraguchi, Ryo
Nakazawa, Kazuo
Medical Prize

Analysis of the Pulmonary Vein Ostia using Cardiac 4DCT for Radiosurgical Ablation

Sumanaweera, Thilaka
Conti, Francois
Maguire, Patrick


BibTeX (Short Papers 2007)
@inproceedings{
10.2312:egs.20071018,
booktitle = {
Eurographics 2007 - Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Preface and Table of Contents}},
author = {
-
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071018}
}
@inproceedings{
10.2312:egs.20071019,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
A Unified Interpolatory and Approximation sqrt-3 Subdivision Scheme}},
author = {
Lin, Shujin
and
Luo, Xiaonan
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071019}
}
@inproceedings{
10.2312:egs.20071021,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Shape Analysis for Augmented Topological Shape Descriptor}},
author = {
Symonova, Olga
and
Amicis, Raffaele De
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071021}
}
@inproceedings{
10.2312:egs.20071022,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Reeb Chart Unfolding Based 3D Shape Signatures}},
author = {
Tierny, Julien
and
Vandeborre, Jean-Philippe
and
Daoudi, Mohamed
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071022}
}
@inproceedings{
10.2312:egs.20071020,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
An Accurate Implicit Field Representation for Meshes and Its Adapted Triangulation Algorithms}},
author = {
Fournier, Marc
and
Dischler, J. - M.
and
Bechmann, D.
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071020}
}
@inproceedings{
10.2312:egs.20071023,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Exact Computation of the Hausdorff Distance between Triangular Meshes}},
author = {
Straub, Raphael
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071023}
}
@inproceedings{
10.2312:egs.20071024,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
View-based Shape Similarity using Mutual Information Spheres}},
author = {
García, Francisco González
and
Feixas, Miquel
and
Sbert, Mateu
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071024}
}
@inproceedings{
10.2312:egs.20071025,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Exemplar-based Worn Edges}},
author = {
Brachmann, Christoph
and
Walther-Franks, Benjamin
and
JörnLoviscach,
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071025}
}
@inproceedings{
10.2312:egs.20071026,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Stabilized Noise}},
author = {
Yoon, Jong-Chul
and
Lee, In-Kwon
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071026}
}
@inproceedings{
10.2312:egs.20071028,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
High Speed Skin Color Detection and Localization on a GPU}},
author = {
Seshadrinathan, Manoj
and
Dempski, Kelly
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071028}
}
@inproceedings{
10.2312:egs.20071027,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Improved Skeleton Computation of an Encoded Volume}},
author = {
Ayala, Dolors
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071027}
}
@inproceedings{
10.2312:egs.20071031,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Volumetric Normal Mapping in Rendering of Multivariate Volume Data}},
author = {
Seipel, Stefan
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071031}
}
@inproceedings{
10.2312:egs.20071029,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Construction of Non-Blobby Surface from Particles}},
author = {
Harada, Takahiro
and
Koshizuka, Seiichi
and
Kawaguchi, Yoichiro
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071029}
}
@inproceedings{
10.2312:egs.20071030,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Enforcing Scene Constraints in Single View Reconstruction}},
author = {
Lourakis, Manolis
and
Argyros, Antonis
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071030}
}
@inproceedings{
10.2312:egs.20071032,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Automated Combination of Real-Time Shader Programs}},
author = {
Trapp, Matthias
and
Döller, Jürgen
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071032}
}
@inproceedings{
10.2312:egs.20071033,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Fast GPU-based Visibility Computation for Natural Illumination of Volume Data Sets}},
author = {
Ritschel, Tobias
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071033}
}
@inproceedings{
10.2312:egs.20071034,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Imperceptible Calibration for Radiometric Compensation}},
author = {
Zollmann, Stefanie
and
Bimber, Oliver
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071034}
}
@inproceedings{
10.2312:egs.20071035,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Object-Oriented Shader Design}},
author = {
Kuck, Roland
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071035}
}
@inproceedings{
10.2312:egs.20071036,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Fast Hierarchical Methods to Detect Collisions between Deformable Objects: A Comparison}},
author = {
Madera, Francisco
and
Day, A. M.
and
Laycock, S. D.
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071036}
}
@inproceedings{
10.2312:egs.20071037,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Simultaneous Visualization of Preoperative Planning Models and Intraoperative 2D Ultrasound for Liver Surgery}},
author = {
Hansen, Christian
and
Köhn, Alexander
and
Zidowitz, Stephan
and
Peitgen, Heinz-Otto
and
Ritter, Felix
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071037}
}
@inproceedings{
10.2312:egs.20071038,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Adaptive Abstraction of 3D scenes in Real-Time}},
author = {
Redmond, Niall
and
Dingliana, John
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071038}
}
@inproceedings{
10.2312:egs.20071039,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Painterly Effects Rendering with Focus Based Level of Detail}},
author = {
Levente, Kovács
and
Tamás, Szirányi
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071039}
}
@inproceedings{
10.2312:egs.20071040,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Liquid Diffusion Model that Accounts for a Variety of Dyeing Parameters}},
author = {
Yuki, Morimoto
and
Tanaka, Masayuki
and
Tsuruno, Reiji
and
Tomimatsu, Kiyoshi
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071040}
}
@inproceedings{
10.2312:egs.20071042,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Fast Hierarchical 3D Distance Transforms on the GPU}},
author = {
Cuntz, Nicolas
and
Kolb, Andreas
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071042}
}
@inproceedings{
10.2312:egs.20071041,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Real-Time 3D Lettering with a 2D Font Engine}},
author = {
Heise, Sebastian
and
Loviscach, Jörn
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071041}
}
@inproceedings{
10.2312:egs.20071044,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Bridging Semantic Web and Digital Shapes}},
author = {
Papaleo, Laura
and
Floriani, Leila De
and
Hendler, Jim
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071044}
}
@inproceedings{
10.2312:egs.20071043,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Spinoff - Transferring Energy between Real and Virtual Worlds}},
author = {
Groenegress, Christoph
and
Slater, Mel
and
Tamke, Martin
and
Thomsen, Mette Ramsgard
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071043}
}
@inproceedings{
10.2312:egs.20071045,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Pareto-Based Perceptual Metric for Imperceptible Simplification on Mobile Displays}},
author = {
Wu, Fan
and
Agu, Emmanuel
and
Lindsay, Clifford
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071045}
}
@inproceedings{
10.2312:egs.20071046,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Take a Stroll in Another World}},
author = {
Ruttkay, Zsofia
and
Orbons, Erik
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071046}
}
@inproceedings{
10.2312:egs.20071047,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Virtual Agent Navigation in Open Spaces using Iterative Shrinking Polygons}},
author = {
Haciomeroglu, Murat
and
Laycock, Robert
and
Day, Andy
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071047}
}
@inproceedings{
10.2312:egs.20071048,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
State-of-the-Art Computer Graphics in Neurosurgical Planning and Risk Assessment}},
author = {
Köhn, Alexander
and
Weiler, Florian
and
Klein, Jan
and
Konrad, Olaf
and
Hahn, Horst
and
Peitgen, Heinz-Otto
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071048}
}
@inproceedings{
10.2312:egs.20071049,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
A Pen-based Interface for Generating Graphical Reports of Findings in Cardiac Catheterization}},
author = {
Mori, Yuki
and
Igarashi, Takeo
and
Haraguchi, Ryo
and
Nakazawa, Kazuo
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071049}
}
@inproceedings{
10.2312:egs.20071050,
booktitle = {
EG Short Papers},
editor = {
Paolo Cignoni and Jiri Sochor
}, title = {{
Analysis of the Pulmonary Vein Ostia using Cardiac 4DCT for Radiosurgical Ablation}},
author = {
Sumanaweera, Thilaka
and
Conti, Francois
and
Maguire, Patrick
}, year = {
2007},
publisher = {
The Eurographics Association},
DOI = {
10.2312/egs.20071050}
}

Browse

Recent Submissions

Now showing 1 - 33 of 33
  • Item
    Preface and Table of Contents
    (The Eurographics Association, 2007) -; Paolo Cignoni and Jiri Sochor
    Preface and Table of Contents
  • Item
    A Unified Interpolatory and Approximation sqrt-3 Subdivision Scheme
    (The Eurographics Association, 2007) Lin, Shujin; Luo, Xiaonan; Paolo Cignoni and Jiri Sochor
    We have found that there is a relationship between the cubic B-spline and four-point curve subdivision method. In the paper it is used to deduce interpolatory subdivision schemes from cubic B-spline based approximation subdivision schemes directly and construct unified schemes for compositing approximation and interpolatory subdivision. A new interpolatory p3 subdivision scheme and a interpolatory and approximation blended p3 subdivision scheme are created by this straightforward method. The former produces C1 limit surface and avoids the problem in the exsiting interpolatory p3 subdivision mask where the weight coefficients on extraordinary vertices can not be described by explicit formulation. The latter can be used to solve the "popping effect" problem when switching between meshes at different levels of resolution, provide the possibility to locally choose an interpolating variant of the conventionally approximating subdivision scheme, and give more flexibility for feature modeling. These are realized by only changing the value of a parameter. The method is thoroughly simple without needs of constructing and solving equations.
  • Item
    Shape Analysis for Augmented Topological Shape Descriptor
    (The Eurographics Association, 2007) Symonova, Olga; Amicis, Raffaele De; Paolo Cignoni and Jiri Sochor
    In this work we propose a scheme for analysis of the shape of a 3D model.We use Extended Reeb Graph to describe the topological structure of the model which we further enrich with extracted geometrical features. The nodes of the graph represent different components of the model, and we propose to analyze their shape separately. Shape characteristics such as taper/enlargement, average curvature, bending are revealed through tracing changes in cross sections of each shape component. Finally the topological structure together with the associated geometrical characteristics represents the shape descriptor of the 3D model.
  • Item
    Reeb Chart Unfolding Based 3D Shape Signatures
    (The Eurographics Association, 2007) Tierny, Julien; Vandeborre, Jean-Philippe; Daoudi, Mohamed; Paolo Cignoni and Jiri Sochor
    This paper presents a novel surface parameterization based technique that addresses the pose insensitive shape signature problem for surface models of arbitrary genus. It is based on the key idea that two surface models are similar if the canonical mappings of their sub-parts introduce similar distortions. First, a Reeb graph of the shape is computed so as to segment it into charts of controlled topology, denoted as Reeb charts, that have either disk or annulus topology. Next, we define for each Reeb chart a straightforward mapping to the canonical planar domain. Then, we compute a stretching signature of the canonical mapping based on an area distortion evaluation. Finally, the input shape is represented by the set of the stretching signatures. An application to pose-insensitive shape similarity is proposed by comparing the signatures of the different Reeb charts. Promising experimental results are presented and compared to state-of-the-art techniques. The gain provided by this new signature as well as its interest for partial shape similarity are demonstrated.
  • Item
    An Accurate Implicit Field Representation for Meshes and Its Adapted Triangulation Algorithms
    (The Eurographics Association, 2007) Fournier, Marc; Dischler, J. - M.; Bechmann, D.; Paolo Cignoni and Jiri Sochor
    The classic implicit scalar field distance transform representation of a mesh is very useful to perform many mesh processing operations and to obtain better results than with other methods. In this paper we propose a new and more accurate implicit vector field distance transform representation of a mesh. We adapt Marching Cube and Marching Triangle, the two most widely used triangulation algorithms, to our new vector field representation to correctly reconstruct the final mesh after data processing in the implicit domain. According to a reliable surface error metric, we show our new vector field is more accurate than the classic scalar field to implicitly represent a mesh. We adapt to our vector field a previously introduced mesh denoising algorithm performed on the scalar field. Results show mesh denoising with our vector field outperforms the one with classic scalar field in terms of an error metric comparison.
  • Item
    Exact Computation of the Hausdorff Distance between Triangular Meshes
    (The Eurographics Association, 2007) Straub, Raphael; Paolo Cignoni and Jiri Sochor
    We present an algorithm that computes the exact Hausdorff distance between two arbitrary triangular meshes. Our method computes squared distances for each point on each triangle of one mesh to all relevant triangles of the other mesh yielding a continuous, piecewise convex quadratic polynomial over domains bounded by conics. The maximum of this polynomial is the one-sided Hausdorff distance from one to the other mesh. We ensure the efficiency of our approach by employing a voxel grid for searching relevant triangles and an attributed half-edge data structure for representing the squared distance function.
  • Item
    View-based Shape Similarity using Mutual Information Spheres
    (The Eurographics Association, 2007) García, Francisco González; Feixas, Miquel; Sbert, Mateu; Paolo Cignoni and Jiri Sochor
    We present a new method for computing the shape similarity between 3D polygonal models using an informationtheoretic viewpoint selection framework. Given a 3D model, a sphere of viewpoints surrounding this model is used to obtain its shape signature from the mutual information of each viewpoint. This signature represents the essence of the shape from a view-based approach. Then, in order to quantify the dissimilarity between two models, their mutual information spheres are registered by minimizing the L2 distance between them. Several experiments show the discrimination capabilities of our approach and its potential suitability for object recognition.
  • Item
    Exemplar-based Worn Edges
    (The Eurographics Association, 2007) Brachmann, Christoph; Walther-Franks, Benjamin; JörnLoviscach,; Paolo Cignoni and Jiri Sochor
    To counteract the sterile look of computer-generated worlds, we introduce a procedural model for worn edges that can be seen in buildings and stones: edges that have suffered minor damage at multiple points, resulting in material being chipped off. Employing data gathered from photographs, the method adds minute detail along exposed edges. The deformed geometry may be simulated with normal maps to also support real-time applications.
  • Item
    Stabilized Noise
    (The Eurographics Association, 2007) Yoon, Jong-Chul; Lee, In-Kwon; Paolo Cignoni and Jiri Sochor
    Perlin noise is generated by interpolation of a pre-defined random number table. However since the random number table is generated without considering the ideal properties of noise for computer graphics, the resulting noise function does not have these properties. We improve the properties of noise for Perlin s and similar algorithms, by stabilizing the random number table itself. We create the noise function using well-known statistical tools that measure the degree of stability of a random number table. These tools are used within an optimization procedure to create a random number table with a uniform random distribution, without periodicity, and having a band-limited property.
  • Item
    High Speed Skin Color Detection and Localization on a GPU
    (The Eurographics Association, 2007) Seshadrinathan, Manoj; Dempski, Kelly; Paolo Cignoni and Jiri Sochor
    In this paper, we present a simple yet novel method for high speed skin color detection and localization on images and video using the Graphics Processing Unit (GPU) and common graphics programming techniques. Our approach is innovative in that it provides a system for skin recognition and localization on the GPU at a speed much higher than that on the CPU. We also test in detail, the performance of different classes of cards and data buses.
  • Item
    Improved Skeleton Computation of an Encoded Volume
    (The Eurographics Association, 2007) Ayala, Dolors; Paolo Cignoni and Jiri Sochor
    In this communication, we present an improvement of an existing thinning algorithm that computes a surface skeleton from a binary volume. The method makes an intensive use of Boolean operations and works on a special encoding of the volume (the EVM encoding) in which Boolean operations are very efficient. The contribution of this work consists on a more suitable application of Boolean operations in the thinning algorithm. Computation time has been reduced more than a half.
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    Volumetric Normal Mapping in Rendering of Multivariate Volume Data
    (The Eurographics Association, 2007) Seipel, Stefan; Paolo Cignoni and Jiri Sochor
    The work presented in this paper introduces volumetric normal maps for producing visual structure in direct volume rendering (DVR) of 3D data for the purpose of visualizing multiple attributes in a 3D volume. We use volumetric normal maps to represent normal vector glyphs that are subsequently applied to warp the gradients in the primary volume data. This method is intended to visualize some secondary attribute in DVR. We demonstrate that our method can render visual structures in DVR without the need of explicit surface reconstruction and texturing.
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    Construction of Non-Blobby Surface from Particles
    (The Eurographics Association, 2007) Harada, Takahiro; Koshizuka, Seiichi; Kawaguchi, Yoichiro; Paolo Cignoni and Jiri Sochor
    This paper presents a method that can construct a surface with a thin region or sharp edges from particles. The surface is constructed in two stages. An implicit surface is generated by assigning a density distribution to each particle in the first step and then the surface constructed from the density distribution is changed to a surface with a thin region or sharp edges. Furthermore, the method can generate various kinds of surfaces because a surface is controlled by several parameters. Therefore, the present technique increases the range of expression of particle-based simulations. In this paper, some calculation results are presented and finally an application from the results of particle-based fluid simulation is discussed.
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    Enforcing Scene Constraints in Single View Reconstruction
    (The Eurographics Association, 2007) Lourakis, Manolis; Argyros, Antonis; Paolo Cignoni and Jiri Sochor
    Three-dimensional reconstruction from a single view is an under-constrained process that relies critically upon the availability of prior knowledge about the imaged scene. This knowledge is assumed to be supplied by a user in the form of geometric constraints such as coplanarity, parallelism, perpendicularity, etc, based on his/her interpretation of the scene. In the presence of noise, however, most of the existing methods yield reconstructions that only approximately satisfy the supplied geometric constraints. This paper proposes a novel single view reconstruction method that provides reconstructions which exactly satisfy all user-supplied constraints. This is achieved by first obtaining a preliminary reconstruction and then refining it in an extendable, constrained optimization framework.
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    Automated Combination of Real-Time Shader Programs
    (The Eurographics Association, 2007) Trapp, Matthias; Döller, Jürgen; Paolo Cignoni and Jiri Sochor
    This work proposes an approach for automatic and generic runtime-combination of high-level shader programs. Many of recently introduced real-time rendering techniques rely on such programs. The fact that only a single program can be active concurrently becomes a main conceptual problem when embedding these techniques into middleware systems or 3D applications. Their implementations frequently demand for a combined use of individual shader functionality and, therefore, need to combine existing shader programs. Such a task is often timeconsuming, error-prone, requires a skilled software engineer, and needs to be repeated for each further extension. Our extensible approach solves these problems efficiently: It structures a shader program into code fragments, each typed with a predefined semantics. Based on an explicit order of those semantics, the code fragments of different programs can be combined at runtime. This technique facilitates the reuse of shader code as well as the development of extensible rendering frameworks for future hardware generations. We integrated our approach into an object-oriented high-level rendering system.
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    Fast GPU-based Visibility Computation for Natural Illumination of Volume Data Sets
    (The Eurographics Association, 2007) Ritschel, Tobias; Paolo Cignoni and Jiri Sochor
    Pre-computed radiance transfer (PRT) has been used to render volumetric data under distant low-frequency illumination at real-time rates, including natural illumination, soft shadows, attenuation from semi-transparent occluders and multiple scattering. PRT requires a lengthy pre-process, which is acceptable only for static volume data. However, in practical volume rendering, general transfer functions are used. Manipulating such a transfer function will result in a dynamic radiance transfer which has to be re-computed. This work proposes a fast way for this re-computation. While previous work has used CPU Monte Carlo ray-tracing for pre-computation and requires time in the order of many minutes, our GPU implementation uses a hierarchical visibility approximation implemented entirely on the GPU and requires only a few seconds for typical scenes.
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    Imperceptible Calibration for Radiometric Compensation
    (The Eurographics Association, 2007) Zollmann, Stefanie; Bimber, Oliver; Paolo Cignoni and Jiri Sochor
    We present a novel multi-step technique for imperceptible geometry and radiometry calibration of projectorcamera systems. Our approach can be used to display geometry and color corrected images on non-optimized surfaces at interactive rates while simultaneously performing a series of invisible structured light projections during runtime. It supports disjoint projector-camera configurations, fast and progressive improvements, as well as real-time correction rates of arbitrary graphical content. The calibration is automatically triggered when misregistrations between camera, projector and surface are detected
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    Object-Oriented Shader Design
    (The Eurographics Association, 2007) Kuck, Roland; Paolo Cignoni and Jiri Sochor
    We present an extremely lightweight object-oriented framework for writing shaders. It provides a way to invoke methods of objects from the shading language and to use references of objects as normal variables. Classes are declared and instantiated in the application language using proxy classes. We then apply object-oriented design to several typical shading problems showing their strength compared to the standard methods.
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    Fast Hierarchical Methods to Detect Collisions between Deformable Objects: A Comparison
    (The Eurographics Association, 2007) Madera, Francisco; Day, A. M.; Laycock, S. D.; Paolo Cignoni and Jiri Sochor
    The time complexity of a collision detection algorithm can be reduced to logarithmic in the number of tests performed when the objects are decomposed into a Bounding Volume (BV) tree hierarchy. It is well known that the Sphere Bounding Volume (SBV) and the Axis Aligned Bounding Box (AABB) hierarchies require inexpensive overlapping tests. However, we present a method called the Distance Hierarchy (DH) which is more suitable for deformable objects and is very simple to implement. It uses a hierarchical tree to decompose each object into regions. Each region requires just one parameter, its radius. In this work we compare three methods, AABB hierarchy, Sphere hierarchy, and DH, where the focus is on the intersection test, computation time, and the use of memory.
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    Simultaneous Visualization of Preoperative Planning Models and Intraoperative 2D Ultrasound for Liver Surgery
    (The Eurographics Association, 2007) Hansen, Christian; Köhn, Alexander; Zidowitz, Stephan; Peitgen, Heinz-Otto; Ritter, Felix; Paolo Cignoni and Jiri Sochor
    This paper introduces new techniques for simultaneous visualization of preoperative planning models and intraoperative 2D ultrasound for open liver surgery. The driving motivation for our work is to improve the visual presentation of a moving ultrasound plane within a complex, interweaving three-dimensional model of hepatic vascular structures. Major drawbacks of existing systems are occlusions of the ultrasound plane by the planning model and fade-out of crucial context information. Our system allows the surgeon to focus on the ultrasound image while perceiving context-relevant planning information without discarding important morphological information and depth cues. The contribution of this paper is a GPU-accelerated rendering pipeline including new illustrative visualization algorithms for focus & context rendering, distance and intersection accentuation, as well as a hybrid technique for high quality silhouette and hatching stroke generation.
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    Adaptive Abstraction of 3D scenes in Real-Time
    (The Eurographics Association, 2007) Redmond, Niall; Dingliana, John; Paolo Cignoni and Jiri Sochor
    We present an approach for creating abstracted renderings of 3D scenes in real-time. We create painterly renderings with edge detail using varying levels of abstraction dependent on regions of interest within a scene. Image space techniques are used to make the system real-time and as non-invasive as possible. This approach can also use object space information to segment the scene into visually important objects and unimportant data and background. Interactive frame rates are achieved by using graphics hardware to perform the computations.
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    Painterly Effects Rendering with Focus Based Level of Detail
    (The Eurographics Association, 2007) Levente, Kovács; Tamás, Szirányi; Paolo Cignoni and Jiri Sochor
    We present a novel method for automatically creating scalable and portable 2D non-photorealistically rendered (NPR) images with painterly effects, with level of detail control. The novelty of the approach lies both in using optical image analysis for automatic focus region extraction, and in producing the painterly rendered images as vector graphics. The approach is also novel in that we automatically extract the regions of higher interest without the need of any tools, devices, or a priori image information. The method is a combination of automatic relative focus map estimation and simple digital strokes for the foreground, and color image segmentation for the background. The images are rendered into scalable vector graphics (SVG) for easy viewing and editing with a variety of existing applications and use in other designs/graphics.
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    Liquid Diffusion Model that Accounts for a Variety of Dyeing Parameters
    (The Eurographics Association, 2007) Yuki, Morimoto; Tanaka, Masayuki; Tsuruno, Reiji; Tomimatsu, Kiyoshi; Paolo Cignoni and Jiri Sochor
    This paper describes a method for simulating and visualizing dyeing based on weave patterns and the physical parameters of the threads and the dye. We apply Fick s second law with a variable diffusion coefficient, which is calculated using the porosity, tortuosity, and the dye concentration based on the physical chemistry of dyeing. The tortuosity of the channel was incorporated in order to consider the effect of weave patterns on diffusion. The total mass is conserved in this model. We describe the cloth model using a two-layered cellular model that includes the minimum factors required for representing the weft and warp. Our model also includes a simple dyeing technique that produces dyeing patterns by interrupting the diffusion of the dye in a cloth using a press. The results obtained using our model demonstrate that it is capable of modeling many of the characteristics of dyeing.
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    Fast Hierarchical 3D Distance Transforms on the GPU
    (The Eurographics Association, 2007) Cuntz, Nicolas; Kolb, Andreas; Paolo Cignoni and Jiri Sochor
    This paper describes a fast approximate approach for the GPU-based computation of 3D Euclidean distance transforms (DT), i.e. distance fields with associated vector information to the closest object point. Our hierarchical method works on discrete voxel grids and uses a propagation technique, both on a single hierarchy level and between the levels. Using our hierarchical approach, the effort to compute the DT is significantly reduced. It is well suited for applications that mainly rely on exact distance values close to the boundary. Our technique is purely GPU-based. All hierarchical operations are performed on the GPU. A direct comparison with the Jump Flooding Algorithm (JFA) shows that our approach is faster and provides better scaling in speed and precision, while JFA should be preferred in applications that require a more precise DT.
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    Real-Time 3D Lettering with a 2D Font Engine
    (The Eurographics Association, 2007) Heise, Sebastian; Loviscach, Jörn; Paolo Cignoni and Jiri Sochor
    Standard texturing shows a number of problems with 3D objects such as road signs, labels, or books. If letters are displayed at too large a scale, textures show blurred instead of hard edges; if letters are displayed at tiny sizes, textures appear either too pixelated or too blurry, but seldom well readable. In 2D as opposed to 3D, letters are created on demand in the required size by a sophisticated font rendering engine, a standard component of today s operating systems. A number of specific improvements such as hinting and RGB subpixel rendering are available. This paper demonstrates how these partially proprietary and patented 2D functions can be leveraged for 3D rendering. The price to pay is a loss in geometric precision, since typical 2D font rendering engines only handle affine transformations, which can merely approximate perspective projection. However, in most situations this is outweighed easily by the gain in clarity.
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    Bridging Semantic Web and Digital Shapes
    (The Eurographics Association, 2007) Papaleo, Laura; Floriani, Leila De; Hendler, Jim; Paolo Cignoni and Jiri Sochor
    Since the volume of multimedia content available on the Web is continuously increasing, a clear need for advanced techniques capable of performing an effective retrieval and management of such data. In this context, in order to reason on digital shapes and their associated semantic, we see a growing interest in exploiting the potential of the Semantic Web in different research fields. We present here the design and initial development of our new system, that we call be-SMART for inspecting digital 3D shapes by extracting geometrical and topological information from them and for structuring and annotating these shapes using ontology-driven metadata. We describe the general structure of the system, its modules and their mutual relations. We also provide motivations for further work in developing new techniques for managing 3D models on the Web.
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    Spinoff - Transferring Energy between Real and Virtual Worlds
    (The Eurographics Association, 2007) Groenegress, Christoph; Slater, Mel; Tamke, Martin; Thomsen, Mette Ramsgard; Paolo Cignoni and Jiri Sochor
    There is a widening gap between interaction devices for Virtual Environments and other factors such as graphical realism, accessibility and complexity. To address this problem, we developed a Mixed Reality environment that allows participants to interact with virtual entities using an existing toy a Hula Hoop. In a subsequent user study we attempted to correlate the use of real artefacts as input devices towards increased interactivity.
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    Pareto-Based Perceptual Metric for Imperceptible Simplification on Mobile Displays
    (The Eurographics Association, 2007) Wu, Fan; Agu, Emmanuel; Lindsay, Clifford; Paolo Cignoni and Jiri Sochor
    Graphics on mobile devices has become popular because untethered computing is convenient and increases pro- ductivity. Mobile displays come in different resolutions that affect the scene Level-of-Detail (LoD) that users can perceive: smaller displays show less detail, making lower resolution meshes and textures acceptable. Mobile de- vices frequently have limited battery energy, low memory and disk space. To minimize wasting system resources, we try to render mobile graphics scenes at the lowest LoD at which users do not perceive distortion due to sim- plification. We call this LoD the Point of Imperceptibility (PoI). The PoI LoD depends on several factors including screen size, scene geometry and lighting levels. We propose a perceptual metric that identifies the PoI LoD of a target mobile display and accounts for object geometry, lighting and shading. Our perceptual metric generates a screen-dependent pareto distribution with a knee point that corresponds to the PoI. We employ wavelets for simplification, which gives direct access to the mesh undulation frequency that we then use to parametrize the perceptual CSF curve.
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    Take a Stroll in Another World
    (The Eurographics Association, 2007) Ruttkay, Zsofia; Orbons, Erik; Paolo Cignoni and Jiri Sochor
    Another World II is a print by the famous Dutch artist M. C. Escher, depicting a cube with arch-like openings on each side. What makes the print interesting is that the depicted views in the arches are inconsistent, leaving the spectator puzzled as to the impossible assembly of views from different perspectives. In our work we invite the reader and more so, the user of our software to explore the strange geometry of this work by flying through a virtual Another World. The rendering of the inconsistent views is achieved by applying Portal Rendering. We point out the novelty of our work with respect to previous 3D computer models of different impossible worlds by M. C. Escher. We also suggest potential application contexts beyond the straightforward 3D reconstruction of Another World.
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    Virtual Agent Navigation in Open Spaces using Iterative Shrinking Polygons
    (The Eurographics Association, 2007) Haciomeroglu, Murat; Laycock, Robert; Day, Andy; Paolo Cignoni and Jiri Sochor
    Populating an urban environment with a virtual crowd provides a dynamic element to an otherwise static scene; bringing the virtual environment to life. One of the fundamental components governing the fidelity of the scene is the realistic simulation of the crowd behaviour. To create a believable crowd simulation one group of methods considers constructing a graph covering the space available to the virtual agents and subsequently performing path planning to allow the agents to navigate their environment by traversing the edges of the graph. To avoid computationally expensive path planning algorithms there exists a tradeoff between the number of edges in the graph and the amount of available space which an agent can visit. In order to alleviate this problem we propose to compute the straight skeleton to provide an initial covering of the environment. This is subsequently augmented using iterative shrinking polygons to generate additional edges in the larger open spaces. The technique developed requires limited knowledge of the urban environment, processes the relevant information automatically and is illustrated in this paper to control the behaviour of a virtual crowd in real time.
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    State-of-the-Art Computer Graphics in Neurosurgical Planning and Risk Assessment
    (The Eurographics Association, 2007) Köhn, Alexander; Weiler, Florian; Klein, Jan; Konrad, Olaf; Hahn, Horst; Peitgen, Heinz-Otto; Paolo Cignoni and Jiri Sochor
    We present a novel software assistant that unlocks new potentials in neurosurgical planning and risk assessment. It allows surgeons to approach the task in an intuitive manner, by providing them with the possibility to simultaneously observe all relevant data of a case in synchronized 2D and 3D views. State-of-the-art technologies from the field of computer graphics are combined to allow simultaneous interactive rendering of anatomical and functional MR data in combination with manually segmented objects and slice-based overlays. This allows surgeons to perceive a clearer impression of the anatomical and functional structures affected by an intervention, and especially the way they are related to each other. Thus, it significantly facilitates the finding of an optimal intervention strategy.
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    A Pen-based Interface for Generating Graphical Reports of Findings in Cardiac Catheterization
    (The Eurographics Association, 2007) Mori, Yuki; Igarashi, Takeo; Haraguchi, Ryo; Nakazawa, Kazuo; Paolo Cignoni and Jiri Sochor
    This paper introduces a pen-based interface for the graphical reporting of findings in cardiac catheterization. The user can interactively draw, erase, move, and deform coronary arteries as well as record stenoses on them. The lo-cation and degree of each stenosis is represented visually and the doctor can record various treatments such as by-passes and stents on the diagram. In addition, the system automatically extracts semantic information from the graphical representation and stores it in XML format. The system can also generate a table in the format specified by the American Heart Association. This system is useful not only as a tool for efficiently generating reports of findings but also as an effective explanation tool for patients.
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    Analysis of the Pulmonary Vein Ostia using Cardiac 4DCT for Radiosurgical Ablation
    (The Eurographics Association, 2007) Sumanaweera, Thilaka; Conti, Francois; Maguire, Patrick; Paolo Cignoni and Jiri Sochor
    A software tool to analyze 4D cardiac CT data sets for planning radiosurgical ablations in the heart is presented. Volume rendering and data processing are performed using a GPU. The user visualizes the data from inside the left atrium and defines the target in 3D using an intuitive user interface. A haptic input device lets the user measure motion at the ostia of the pulmonary veins for radiosurgical treatment planning. This tool has been used effectively for generating radiation treatment plans for animal studies.