29-Issue 2

Permanent URI for this collection

https://diglib7.eg.org/handle/10.2312/153
EG Proceedings

BibTeX (29-Issue 2)
                
@article{
10.1111:j.1467-8659.2009.01594.x,

journal = {Computer Graphics Forum},
title = {{
TouchTone: Interactive Local Image Adjustment Using Point-and-Swipe}},

author = {
Liang, Chia-Kai
 and 
Chen, Wei-Chao
 and 
Gelfand, Natasha
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01594.x}

}
                
@article{
10.1111:j.1467-8659.2009.01595.x,

journal = {Computer Graphics Forum},
title = {{
User-Controllable Color Transfer}},

author = {
An, Xiaobo
 and 
Pellacini, Fabio
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01595.x}

}
                
@article{
10.1111:j.1467-8659.2009.01596.x,

journal = {Computer Graphics Forum},
title = {{
Contrast-aware Halftoning}},

author = {
Li, Hua
 and 
Mould, David
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01596.x}

}
                
@article{
10.1111:j.1467-8659.2009.01597.x,

journal = {Computer Graphics Forum},
title = {{
Fitted BVH for Fast Raytracing of Metaballs}},

author = {
Gourmel, Olivier
 and 
Pajot, Anthony
 and 
Paulin, Mathias
 and 
Barthe, Loic
 and 
Poulin, Pierre
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01597.x}

}
                
@article{
10.1111:j.1467-8659.2009.01598.x,

journal = {Computer Graphics Forum},
title = {{
Fast Ray Sorting and Breadth-First Packet Traversal for GPU Ray Tracing}},

author = {
Garanzha, Kirill
 and 
Loop, Charles
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01598.x}

}
                
@article{
10.1111:j.1467-8659.2009.01599.x,

journal = {Computer Graphics Forum},
title = {{
HCCMeshes: Hierarchical-Culling oriented Compact Meshes}},

author = {
Kim, Tae-Joon
 and 
Byun, Yongyoung
 and 
Kim, Yongjin
 and 
Moon, Bochang
 and 
Lee, Seungyong
 and 
Yoon, Sung-Eui
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01599.x}

}
                
@article{
10.1111:j.1467-8659.2009.01600.x,

journal = {Computer Graphics Forum},
title = {{
Multi-Scale Geometry Interpolation}},

author = {
Winkler, T.
 and 
Drieseberg, J.
 and 
Alexa, M.
 and 
Hormann, K.
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01600.x}

}
                
@article{
10.1111:j.1467-8659.2009.01601.x,

journal = {Computer Graphics Forum},
title = {{
Deformation Transfer to Multi-Component Objects}},

author = {
Zhou, Kun
 and 
Xu, Weiwei
 and 
Tong, Yiying
 and 
Desbrun, Mathieu
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01601.x}

}
                
@article{
10.1111:j.1467-8659.2009.01602.x,

journal = {Computer Graphics Forum},
title = {{
Fast and Efficient Skinning of Animated Meshes}},

author = {
Kavan, L.
 and 
Sloan, P.-P.
 and 
O Sullivan, C.
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01602.x}

}
                
@article{
10.1111:j.1467-8659.2009.01603.x,

journal = {Computer Graphics Forum},
title = {{
Interactive High-Quality Visualization of Higher-Order Finite Elements}},

author = {
Ueffinger, Markus
 and 
Frey, Steffen
 and 
Ertl, Thomas
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01603.x}

}
                
@article{
10.1111:j.1467-8659.2009.01604.x,

journal = {Computer Graphics Forum},
title = {{
Uncertain 2D Vector Field Topology}},

author = {
Otto, Mathias
 and 
Germer, Tobias
 and 
Hege, Hans-Christian
 and 
Theisel, Holger
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01604.x}

}
                
@article{
10.1111:j.1467-8659.2009.01605.x,

journal = {Computer Graphics Forum},
title = {{
SoundRiver: Semantically-Rich Sound Illustration}},

author = {
Jaenicke, H.
 and 
Borgo, R.
 and 
Mason, J. S. D.
 and 
Chen, M.
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01605.x}

}
                
@article{
10.1111:j.1467-8659.2009.01607.x,

journal = {Computer Graphics Forum},
title = {{
Isosurfaces Over Simplicial Partitions of Multiresolution Grids}},

author = {
Manson, Josiah
 and 
Schaefer, Scott
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01607.x}

}
                
@article{
10.1111:j.1467-8659.2009.01606.x,

journal = {Computer Graphics Forum},
title = {{
Implicit Blending Revisited}},

author = {
Bernhardt, Adrien
 and 
Barthe, Loic
 and 
Cani, Marie-Paule
 and 
Wyvill, Brian
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01606.x}

}
                
@article{
10.1111:j.1467-8659.2009.01609.x,

journal = {Computer Graphics Forum},
title = {{
Exact and Robust (Self-)Intersections for Polygonal Meshes}},

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

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01609.x}

}
                
@article{
10.1111:j.1467-8659.2009.01608.x,

journal = {Computer Graphics Forum},
title = {{
Global Illumination Compensation for Spatially Augmented Reality}},

author = {
Sheng, Yu
 and 
Yapo, Theodore C.
 and 
Cutler, Barbara
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01608.x}

}
                
@article{
10.1111:j.1467-8659.2009.01610.x,

journal = {Computer Graphics Forum},
title = {{
Practical quad mesh simplification}},

author = {
Tarini, Marco
 and 
Pietroni, Nico
 and 
Cignoni, Paolo
 and 
Panozzo, Daniele
 and 
Puppo, Enrico
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01610.x}

}
                
@article{
10.1111:j.1467-8659.2009.01611.x,

journal = {Computer Graphics Forum},
title = {{
gProximity: Hierarchical GPU-based Operations for Collision and Distance Queries}},

author = {
Lauterbach, C.
 and 
Mo, Q.
 and 
Manocha, D.
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01611.x}

}
                
@article{
10.1111:j.1467-8659.2009.01612.x,

journal = {Computer Graphics Forum},
title = {{
Procedural Generation of Roads}},

author = {
Galin, E.
 and 
Peytavie, A.
 and 
Marechal, N.
 and 
Guerin, E.
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01612.x}

}
                
@article{
10.1111:j.1467-8659.2009.01613.x,

journal = {Computer Graphics Forum},
title = {{
Continuum Traffic Simulation}},

author = {
Sewall, J.
 and 
Wilkie, D.
 and 
Merrell, P.
 and 
Lin, M. C.
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01613.x}

}
                
@article{
10.1111:j.1467-8659.2009.01614.x,

journal = {Computer Graphics Forum},
title = {{
Heat Transfer Simulation for Modeling Realistic Winter Sceneries}},

author = {
Marechal, N.
 and 
Guerin, E.
 and 
Galin, E.
 and 
Merillou, S.
 and 
Merillou, N.
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01614.x}

}
                
@article{
10.1111:j.1467-8659.2009.01615.x,

journal = {Computer Graphics Forum},
title = {{
Puzzle-like Collage}},

author = {
Goferman, Stas
 and 
Tal, Ayellet
 and 
Zelnik-Manor, Lihi
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01615.x}

}
                
@article{
10.1111:j.1467-8659.2009.01616.x,

journal = {Computer Graphics Forum},
title = {{
Optimizing Photo Composition}},

author = {
Liu, Ligang
 and 
Chen, Renjie
 and 
Wolf, Lior
 and 
Cohen-Or, Daniel
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01616.x}

}
                
@article{
10.1111:j.1467-8659.2009.01617.x,

journal = {Computer Graphics Forum},
title = {{
Seamless Montage for Texturing Models}},

author = {
Gal, Ran
 and 
Wexler, Yonatan
 and 
Ofek, Eyal
 and 
Hoppe, Hugues
 and 
Cohen-Or, Daniel
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01617.x}

}
                
@article{
10.1111:j.1467-8659.2009.01619.x,

journal = {Computer Graphics Forum},
title = {{
Real-time Rendering of Heterogeneous Translucent Objects with Arbitrary Shapes}},

author = {
Wang, Yajun
 and 
Wang, Jiaping
 and 
Holzschuch, Nicolas
 and 
Subr, Kartic
 and 
Yong, Jun-Hai
 and 
Guo, Baining
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01619.x}

}
                
@article{
10.1111:j.1467-8659.2009.01618.x,

journal = {Computer Graphics Forum},
title = {{
Real-time Realistic Ocean Lighting using Seamless Transitions from Geometry to BRDF}},

author = {
Bruneton, Eric
 and 
Neyret, Fabrice
 and 
Holzschuch, Nicolas
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01618.x}

}
                
@article{
10.1111:j.1467-8659.2009.01622.x,

journal = {Computer Graphics Forum},
title = {{
Mesh Decomposition with Cross-Boundary Brushes}},

author = {
Zheng, Youyi
 and 
Tai, Chiew-Lan
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01622.x}

}
                
@article{
10.1111:j.1467-8659.2009.01620.x,

journal = {Computer Graphics Forum},
title = {{
Rendering Wave Effects with Augmented Light Field}},

author = {
Oh, Se Baek
 and 
Kashyap, Sriram
 and 
Garg, Rohit
 and 
Chandran, Sharat
 and 
Raskar, Ramesh
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01620.x}

}
                
@article{
10.1111:j.1467-8659.2009.01621.x,

journal = {Computer Graphics Forum},
title = {{
Mesh Snapping: Robust Interactive Mesh Cutting Using Fast Geodesic Curvature Flow}},

author = {
Zhang, Juyong
 and 
Wu, Chunlin
 and 
Cai, Jianfei
 and 
Zheng, Jianmin
 and 
Tai, Xue-cheng
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01621.x}

}
                
@article{
10.1111:j.1467-8659.2009.01623.x,

journal = {Computer Graphics Forum},
title = {{
A Data-driven Segmentation for the Shoulder Complex}},

author = {
Hong, Q Youn
 and 
Park, Sang Il
 and 
Hodgins, Jessica K.
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01623.x}

}
                
@article{
10.1111:j.1467-8659.2009.01625.x,

journal = {Computer Graphics Forum},
title = {{
Synthesis of Responsive Motion Using a Dynamic Model}},

author = {
Ye, Yuting
 and 
Liu, C. Karen
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01625.x}

}
                
@article{
10.1111:j.1467-8659.2009.01624.x,

journal = {Computer Graphics Forum},
title = {{
Human Motion Synthesis with Optimization-based Graphs}},

author = {
Ren, Cheng
 and 
Zhao, Liming
 and 
Safonova, Alla
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01624.x}

}
                
@article{
10.1111:j.1467-8659.2009.01626.x,

journal = {Computer Graphics Forum},
title = {{
Bidirectional Search for Interactive Motion Synthesis}},

author = {
Lo, Wan-Yen
 and 
Zwicker, Matthias
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01626.x}

}
                
@article{
10.1111:j.1467-8659.2009.01627.x,

journal = {Computer Graphics Forum},
title = {{
Shared Sampling for Real-Time Alpha Matting}},

author = {
Gastal, Eduardo S. L.
 and 
Oliveira, Manuel M.
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01627.x}

}
                
@article{
10.1111:j.1467-8659.2009.01628.x,

journal = {Computer Graphics Forum},
title = {{
Articulated Billboards for Video-based Rendering}},

author = {
Germann, Marcel
 and 
Hornung, Alexander
 and 
Keiser, Richard
 and 
Ziegler, Remo
 and 
Wuermlin, Stephan
 and 
Gross, Markus
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01628.x}

}
                
@article{
10.1111:j.1467-8659.2009.01630.x,

journal = {Computer Graphics Forum},
title = {{
BetweenIT: An Interactive Tool for Tight Inbetweening}},

author = {
Whited, Brian
 and 
Noris, Gioacchino
 and 
Simmons, Maryann
 and 
Sumner, Robert W.
 and 
Gross, Markus
 and 
Rossignac, Jarek
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01630.x}

}
                
@article{
10.1111:j.1467-8659.2009.01629.x,

journal = {Computer Graphics Forum},
title = {{
The Virtual Director: a Correlation-Based Online Viewing of Human Motion}},

author = {
Assa, J.
 and 
Wolf, L.
 and 
Cohen-Or, D.
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01629.x}

}
                
@article{
10.1111:j.1467-8659.2009.01631.x,

journal = {Computer Graphics Forum},
title = {{
Adding Depth to Cartoons Using Sparse Depth (In)equalities}},

author = {
Sykora, D.
 and 
Sedlacek, D.
 and 
Jinchao, S.
 and 
Dingliana, J.
 and 
Collins, S.
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01631.x}

}
                
@article{
10.1111:j.1467-8659.2009.01632.x,

journal = {Computer Graphics Forum},
title = {{
Printed Patterns for Enhanced Shape Perception of Papercraft Models}},

author = {
Xue, Su
 and 
Chen, Xuejin
 and 
Dorsey, Julie
 and 
Rushmeier, Holly
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01632.x}

}
                
@article{
10.1111:j.1467-8659.2009.01633.x,

journal = {Computer Graphics Forum},
title = {{
Consensus Skeleton for Non-rigid Space-time Registration}},

author = {
Zheng, Q.
 and 
Sharf, A.
 and 
Tagliasacchi, A.
 and 
Chen, B.
 and 
Zhang, H.
 and 
Sheffer, A.
 and 
Cohen-Or, D.
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01633.x}

}
                
@article{
10.1111:j.1467-8659.2009.01634.x,

journal = {Computer Graphics Forum},
title = {{
Electors Voting for Fast Automatic Shape Correspondence}},

author = {
Kin-Chung Au, Oscar
 and 
Tai, Chiew-Lan
 and 
Cohen-Or, Daniel
 and 
Zheng, Youyi
 and 
Fu, Hongbo
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01634.x}

}
                
@article{
10.1111:j.1467-8659.2009.01635.x,

journal = {Computer Graphics Forum},
title = {{
Sketching Clothoid Splines Using Shortest Paths}},

author = {
Baran, Ilya
 and 
Lehtinen, Jaakko
 and 
Popovic, Jovan
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01635.x}

}
                
@article{
10.1111:j.1467-8659.2009.01636.x,

journal = {Computer Graphics Forum},
title = {{
Inverse Procedural Modeling by Automatic Generation of L-systems}},

author = {
St ava, O.
 and 
Benes, B.
 and 
Mech, R.
 and 
Aliaga, D. G.
 and 
Kristof, P.
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01636.x}

}
                
@article{
10.1111:j.1467-8659.2009.01637.x,

journal = {Computer Graphics Forum},
title = {{
Hybrid Simulation of Miscible Mixing with Viscous Fingering}},

author = {
Shin, Seung-Ho
 and 
Kam, Hyeong Ryeol
 and 
Kim, Chang-Hun
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01637.x}

}
                
@article{
10.1111:j.1467-8659.2009.01638.x,

journal = {Computer Graphics Forum},
title = {{
A Hybrid Approach to Multiple Fluid Simulation using Volume Fractions}},

author = {
Kang, Nahyup
 and 
Park, Jinho
 and 
Noh, Junyong
 and 
Shin, Sung Yong
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01638.x}

}
                
@article{
10.1111:j.1467-8659.2009.01639.x,

journal = {Computer Graphics Forum},
title = {{
Tetrahedral Embedded Boundary Methods for Accurate and Flexible Adaptive Fluids}},

author = {
Batty, Christopher
 and 
Xenos, Stefan
 and 
Houston, Ben
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01639.x}

}
                
@article{
10.1111:j.1467-8659.2009.01640.x,

journal = {Computer Graphics Forum},
title = {{
Improved Variational Guiding of Smoke Animations}},

author = {
Nielsen, Michael B.
 and 
Christensen, Brian B.
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01640.x}

}
                
@article{
10.1111:j.1467-8659.2009.01641.x,

journal = {Computer Graphics Forum},
title = {{
Perceptually-motivated Real-time Temporal Upsampling of 3D Content for High-refresh-rate Displays}},

author = {
Didyk, Piotr
 and 
Eisemann, Elmar
 and 
Ritschel, Tobias
 and 
Myszkowski, Karol
 and 
Seidel, Hans-Peter
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01641.x}

}
                
@article{
10.1111:j.1467-8659.2009.01642.x,

journal = {Computer Graphics Forum},
title = {{
Scalable Height Field Self-Shadowing}},

author = {
Timonen, Ville
 and 
Westerholm, Jan
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01642.x}

}
                
@article{
10.1111:j.1467-8659.2009.01643.x,

journal = {Computer Graphics Forum},
title = {{
Motion Blur for EWA Surface Splatting}},

author = {
Heinzle, Simon
 and 
Wolf, Johanna
 and 
Kanamori, Yoshihiro
 and 
Weyrich, Tim
 and 
Nishita, Tomoyuki
 and 
Gross, Markus
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01643.x}

}
                
@article{
10.1111:j.1467-8659.2009.01644.x,

journal = {Computer Graphics Forum},
title = {{
Two-Colored Pixels}},

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

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01644.x}

}
                
@article{
10.1111:j.1467-8659.2009.01645.x,

journal = {Computer Graphics Forum},
title = {{
Fast High-Dimensional Filtering Using the Permutohedral Lattice}},

author = {
Adams, Andrew
 and 
Baek, Jongmin
 and 
Davis, Myers Abraham
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01645.x}

}
                
@article{
10.1111:j.1467-8659.2009.01646.x,

journal = {Computer Graphics Forum},
title = {{
Reinterpretable Imager: Towards Variable Post-Capture Space, Angle and Time Resolution in Photography}},

author = {
Agrawal, Amit
 and 
Veeraraghavan, Ashok
 and 
Raskar, Ramesh
},
year = {
2010},

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


ISSN = {1467-8659},

DOI = {
10.1111/j.1467-8659.2009.01646.x}

}

Browse

Recent Submissions

Now showing 1 - 54 of 54
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    Frontmatter EG 2010
    (The Eurographics Association and Blackwell Publishing Ltd, 2010)
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    TouchTone: Interactive Local Image Adjustment Using Point-and-Swipe
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Liang, Chia-Kai; Chen, Wei-Chao; Gelfand, Natasha
    Recent proliferation of camera phones, photo sharing and social network services has significantly changed how we process our photos. Instead of going through the traditional download-edit-share cycle using desktop editors, an increasing number of photos are taken with camera phones and published through cellular networks. The immediacy of the sharing process means that on-device image editing, if needed, should be quick and intuitive. However, due to the limited computational resources and vastly different user interaction model on small screens, most traditional local selection methods can not be directly adapted to mobile devices. To address this issue, we present TouchTone, a new method for edge-aware image adjustment using simple finger gestures. Our method enables users to select regions within the image and adjust their corresponding photographic attributes simultaneously through a simple point-and-swipe interaction. To enable fast interaction, we develop a memory- and computation-efficient algorithm which samples a collection of 1D paths from the image, computes the adjustment solution along these paths, and interpolates the solutions to entire image through bilateral filtering. Our system is intuitive to use, and can support several local editing tasks, such as brightness, contrast, and color balance adjustments, within a minute on a mobile device.
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    User-Controllable Color Transfer
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) An, Xiaobo; Pellacini, Fabio
    This paper presents an image editing framework where users use reference images to indicate desired color edits. In our approach, users specify pairs of strokes to indicate corresponding regions in both the original and the reference image that should have the same color style . Within each stroke pair, a nonlinear constrained parametric transfer model is used to transfer the reference colors to the original. We estimate the model parameters by matching color distributions, under constraints that ensure no visual artifacts are present in the transfer result. To perform transfer on the whole image, we employ optimization methods to propagate the model parameters defined at each stroke location to spatially-close regions of similar appearance. This stroke-based formulation requires minimal user effort while retaining the high degree of user control necessary to allow artistic interpretations. We demonstrate our approach by performing color transfer on a number of image pairs varying in content and style, and show that our algorithm outperforms state-of-the-art color transfer methods on both user-controllability and visual qualities of the transfer results.
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    Contrast-aware Halftoning
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Li, Hua; Mould, David
    This paper proposes two variants of a simple but efficient algorithm for structure-preserving halftoning. Our algorithm extends Floyd-Steinberg error diffusion; the goal of our extension is not only to produce good tone similarity but also to preserve structure and especially contrast, motivated by our intuition that human perception is sensitive to contrast. By enhancing contrast we attempt to preserve and enhance structure also.Our basic algorithm employs an adaptive, contrast-aware mask. To enhance contrast, darker pixels should be more likely to be chosen as black pixels while lighter pixels should be more likely to be set as white. Therefore, when the positive error is diffused to nearby pixels in a mask, the dark pixels absorb less error and the light pixels absorb more. Conversely, negative error is distributed preferentially to dark pixels. We also propose using a mask with values that drop off steeply from the centre, intended to promote good spatial distribution. It is a very fast method whose speed mainly depends on the size of the mask. But this method suffers from distracting patterns.We then propose a variant on the basic idea which overcomes the first algorithm s shortcomings while maintaining its advantages through a priority-aware scheme. Rather than proceeding in random or raster order, we sort the image first; each pixel is assigned a priority based on its up-to-date distance to black or to white, and pixels with extreme intensities are processed earlier. Since we use the same mask strategy as before, we promote good spatial distribution and high contrast.We use tone similarity, structure similarity, and contrast similarity to validate our algorithm. Comparisons with recent structure-aware algorithms show that our method gives better results without sacrificing speed.
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    Fitted BVH for Fast Raytracing of Metaballs
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Gourmel, Olivier; Pajot, Anthony; Paulin, Mathias; Barthe, Loic; Poulin, Pierre
    Raytracing metaballs is a problem that has numerous applications in the rendering of dynamic soft objects such as fluids. However, current techniques are either limited in the visual effects that they can render or their performance drops as the number of metaballs and their density increase. We present a new acceleration structure based on BVH and kd-tree for efficient raytracing of a large number of metaballs. This structure is built from an adapted SAH using a fast greedy algorithm and allows the visualization of several hundreds of thousands metaballs at interactive-to-real-time framerates. Our method can handle arbitrary rays to simulate any complex secondary effects such as reflections or soft shadows, and is robust with respect to the density of metaballs. We achieve this performance thanks to a balanced CPU-GPU (using CUDA) implementation of the animation, structure creation, and rendering.
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    Fast Ray Sorting and Breadth-First Packet Traversal for GPU Ray Tracing
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Garanzha, Kirill; Loop, Charles
    We present a novel approach to ray tracing execution on commodity graphics hardware using CUDA. We decompose a standard ray tracing algorithm into several data-parallel stages that are mapped efficiently to the massively parallel architecture of modern GPUs. These stages include: ray sorting into coherent packets, creation of frustums for packets, breadth-first frustum traversal through a bounding volume hierarchy for the scene, and localized ray-primitive intersections. We utilize the well known parallel primitives scan and segmented scan in order to process irregular data structures, to remove the need for a stack, and to minimize branch divergence in all stages. Our ray sorting stage is based on applying hash values to individual rays, ray stream compression, sorting and decompression. Our breadth-first BVH traversal is based on parallel frustum-bounding box intersection tests and parallel scan per each BVH level.We demonstrate our algorithm with area light sources to get a soft shadow effect and show that our concept is reasonable for GPU implementation. For the same data sets and ray-primitive intersection routines our pipeline is 3x faster than an optimized standard depth first ray tracing implemented in one kernel.
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    HCCMeshes: Hierarchical-Culling oriented Compact Meshes
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Kim, Tae-Joon; Byun, Yongyoung; Kim, Yongjin; Moon, Bochang; Lee, Seungyong; Yoon, Sung-Eui
    Hierarchical culling is a key acceleration technique used to efficiently handle massive models for ray tracing, collision detection, etc. To support such hierarchical culling, bounding volume hierarchies (BVHs) combined with meshes are widely used. However, BVHs may require a very large amount of memory space, which can negate the benefits of using BVHs. To address this problem, we present a novel hierarchical-culling oriented compact mesh representation, HCCMesh, which tightly integrates a mesh and a BVH together. As an in-core representation of the HCCMesh, we propose an i-HCCMesh representation that provides an efficient random hierarchical traversal and high culling efficiency with a small runtime decompression overhead. To further reduce the storage requirement, the in-core representation is compressed to our out-of-core representation, o-HCCMesh, by using a simple dictionary-based compression method. At runtime, o-HCCMeshes are fetched from an external drive and decompressed to the i-HCCMeshes stored in main memory. The i-HCCMesh and o-HCCMesh show 3.6:1 and 10.4:1 compression ratios on average, compared to a naively compressed (e.g., quantized) mesh and BVH representation. We test the HCCMesh representations with ray tracing, collision detection, photon mapping, and non-photorealistic rendering. Because of the reduced data access time, a smaller working set size, and a low runtime decompression overhead, we can handle models ten times larger in commodity hardware without the expensive disk I/O thrashing. When we avoid the disk I/O thrashing using our representation, we can improve the runtime performances by up to two orders of magnitude over using a naively compressed representation.
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    Multi-Scale Geometry Interpolation
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Winkler, T.; Drieseberg, J.; Alexa, M.; Hormann, K.
    Interpolating vertex positions among triangle meshes with identical vertex-edge graphs is a fundamental part of many geometric modelling systems. Linear vertex interpolation is robust but fails to preserve local shape. Most recent approaches identify local affine transformations for parts of the mesh, model desired interpolations of the affine transformations, and then optimize vertex positions to conform with the desired transformations. However, the local interpolation of the rotational part is non-trivial for more than two input configurations and ambiguous if the meshes are deformed significantly. We propose a solution to the vertex interpolation problem that starts from interpolating the local metric (edge lengths) and mean curvature (dihedral angles) and makes consistent choices of local affine transformations using shape matching applied to successively larger parts of the mesh. The local interpolation can be applied to any number of input vertex configurations and due to the hierarchical scheme for generating consolidated vertex positions, the approach is fast and can be applied to very large meshes.
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    Deformation Transfer to Multi-Component Objects
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Zhou, Kun; Xu, Weiwei; Tong, Yiying; Desbrun, Mathieu
    We present a simple and effective algorithm to transfer deformation between surface meshes with multiple components. The algorithm automatically computes spatial relationships between components of the target object, builds correspondences between source and target, and finally transfers deformation of the source onto the target while preserving cohesion between the target s components. We demonstrate the versatility of our approach on various complex models.
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    Fast and Efficient Skinning of Animated Meshes
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Kavan, L.; Sloan, P.-P.; O Sullivan, C.
    Skinning is a simple yet popular deformation technique combining compact storage with efficient hardware accelerated rendering. While skinned meshes (such as virtual characters) are traditionally created by artists, previous work proposes algorithms to construct skinning automatically from a given vertex animation. However, these methods typically perform well only for a certain class of input sequences and often require long pre-processing times. We present an algorithm based on iterative coordinate descent optimization which handles arbitrary animations and produces more accurate approximations than previous techniques, while using only standard linear skinning without any modifications or extensions. To overcome the computational complexity associated with the iterative optimization, we work in a suitable linear subspace (obtained by quick approximate dimensionality reduction) and take advantage of the typically very sparse vertex weights. As a result, our method requires about one or two orders of magnitude less pre-processing time than previous methods.
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    Interactive High-Quality Visualization of Higher-Order Finite Elements
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Ueffinger, Markus; Frey, Steffen; Ertl, Thomas
    Higher-order finite element methods have emerged as an important discretization scheme for simulation. They are increasingly used in contemporary numerical solvers, generating a new class of data that must be analyzed by scientists and engineers. Currently available visualization tools for this type of data are either batch oriented or limited to certain cell types and polynomial degrees. Other approaches approximate higher-order data by resampling resulting in trade-offs in interactivity and quality. To overcome these limitations, we have developed a distributed visualization system which allows for interactive exploration of non-conforming unstructured grids, resulting from space-time discontinuous Galerkin simulations, in which each cell has its own higher-order polynomial solution. Our system employs GPU-based raycasting for direct volume rendering of complex grids which feature non-convex, curvilinear cells with varying polynomial degree. Frequency-based adaptive sampling accounts for the high variations along rays. For distribution across a GPU cluster, the initial object-space partitioning is determined by cell characteristics like the polynomial degree and is adapted at runtime by a load balancing mechanism. The performance and utility of our system is evaluated for different aeroacoustic simulations involving the propagation of shock fronts.
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    Uncertain 2D Vector Field Topology
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Otto, Mathias; Germer, Tobias; Hege, Hans-Christian; Theisel, Holger
    We introduce an approach to visualize stationary 2D vector fields with global uncertainty obtained by considering the transport of local uncertainty in the flow. For this, we extend the concept of vector field topology to uncertain vector fields by considering the vector field as a density distribution function. By generalizing the concepts of stream lines and critical points we obtain a number of density fields representing an uncertain topological segmentation. Their visualization as height surfaces gives insight into both the flow behavior and its uncertainty. We present a Monte Carlo approach where we integrate probabilistic particle paths, which lead to the segmentation of topological features. Moreover, we extend our algorithms to detect saddle points and present efficient implementations. Finally, we apply our technique to a number of real and synthetic test data sets.
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    SoundRiver: Semantically-Rich Sound Illustration
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Jaenicke, H.; Borgo, R.; Mason, J. S. D.; Chen, M.
    Sound is an integral part of most movies and videos. In many situations, viewers of a video are unable to hear the sound track, for example, when watching it in a fast forward mode, viewing it by hearing-impaired viewers or when the plot is given as a storyboard. In this paper, we present an automated visualization solution to such problems. The system first detects the common components (such as music, speech, rain, explosions, and so on) from a sound track, then maps them to a collection of programmable visual metaphors, and generates a composite visualization. This form of sound visualization, which is referred to as SoundRiver, can be also used to augment various forms of video abstraction and annotated key frames and to enhance graphical user interfaces for video handling software. The SoundRiver conveys more semantic information to the viewer than traditional graphical representations of sound illustration, such as phonoautographs, spectrograms or artistic audiovisual animations.
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    Isosurfaces Over Simplicial Partitions of Multiresolution Grids
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Manson, Josiah; Schaefer, Scott
    We provide a simple method that extracts an isosurface that is manifold and intersection-free from a function over an arbitrary octree. Our method samples the function dual to minimal edges, faces, and cells, and we show how to position those samples to reconstruct sharp and thin features of the surface. Moreover, we describe an error metric designed to guide octree expansion such that flat regions of the function are tiled with fewer polygons than curved regions to create an adaptive polygonalization of the isosurface. We then show how to improve the quality of the triangulation by moving dual vertices to the isosurface and provide a topological test that guarantees we maintain the topology of the surface. While we describe our algorithm in terms of extracting surfaces from volumetric functions, we also show that our algorithm extends to generating manifold level sets of co-dimension 1 of functions of arbitrary dimension.
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    Implicit Blending Revisited
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Bernhardt, Adrien; Barthe, Loic; Cani, Marie-Paule; Wyvill, Brian
    Blending is both the strength and the weakness of functionally based implicit surfaces (such as F-reps or soft-objects). While it gives them the unique ability to smoothly merge into a single, arbitrary shape, it makes implicit modelling hard to control since implicit surfaces blend at a distance, in a way that heavily depends on the slope of the field functions that define them. This paper presents a novel, generic solution to blending of functionally-based implicit surfaces: the insight is that to be intuitive and easy to control, blends should be located where two objects overlap, while enabling other parts of the objects to come as close to each other as desired without being deformed. Our solution relies on automatically defined blending regions around the intersection curves between two objects. Outside of these volumes, a clean union of the objects is computed thanks to a new operator that guarantees the smoothness of the resulting field function; meanwhile, a smooth blend is generated inside the blending regions. Parameters can automatically be tuned in order to prevent small objects from blurring out when blended into larger ones, and to generate a progressive blend when two animated objects come in contact.
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    Exact and Robust (Self-)Intersections for Polygonal Meshes
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Campen, Marcel; Kobbelt, Leif
    We present a new technique to implement operators that modify the topology of polygonal meshes at intersections and self-intersections. Depending on the modification strategy, this effectively results in operators for Boolean combinations or for the construction of outer hulls that are suited for mesh repair tasks and accurate mesh-based front tracking of deformable materials that split and merge. By combining an adaptive octree with nested binary space partitions (BSP), we can guarantee exactness (= correctness) and robustness (= completeness) of the algorithm while still achieving higher performance and less memory consumption than previous approaches. The efficiency and scalability in terms of runtime and memory is obtained by an operation localization scheme. We restrict the essential computations to those cells in the adaptive octree where intersections actually occur. Within those critical cells, we convert the input geometry into a plane-based BSP-representation which allows us to perform all computations exactly even with fixed precision arithmetics. We carefully analyze the precision requirements of the involved geometric data and predicates in order to guarantee correctness and show how minimal input mesh quantization can be used to safely rely on computations with standard floating point numbers. We properly evaluate our method with respect to precision, robustness, and efficiency.
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    Global Illumination Compensation for Spatially Augmented Reality
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Sheng, Yu; Yapo, Theodore C.; Cutler, Barbara
    When projectors are used to display images on complex, non-planar surface geometry, indirect illumination between the surfaces will disrupt the final appearance of this imagery, generally increasing brightness, decreasing contrast, and washing out colors. In this paper we predict through global illumination simulation this unintentional indirect component and solve for the optimal compensated projection imagery that will minimize the difference between the desired imagery and the actual total illumination in the resulting physical scene. Our method makes use of quadratic programming to minimize this error within the constraints of the physical system, namely, that negative light is physically impossible. We demonstrate our compensation optimization in both computer simulation and physical validation within a table-top spatially augmented reality system. We present an application of these results for visualization of interior architectural illumination. To facilitate interactive modifications to the scene geometry and desired appearance, our system is accelerated with a CUDA implementation of the QP optimization method.
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    Practical quad mesh simplification
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Tarini, Marco; Pietroni, Nico; Cignoni, Paolo; Panozzo, Daniele; Puppo, Enrico
    In this paper we present an innovative approach to incremental quad mesh simplification, i.e. the task of producing a low complexity quad mesh starting from a high complexity one. The process is based on a novel set of strictly local operations which preserve quad structure. We show how good tessellation quality (e.g. in terms of vertex valencies) can be achieved by pursuing uniform length and canonical proportions of edges and diagonals. The decimation process is interleaved with smoothing in tangent space. The latter strongly contributes to identify a suitable sequence of local modification operations. The method is naturally extended to manage preservation of feature lines (e.g. creases) and varying (e.g. adaptive) tessellation densities. We also present an original Triangle-to-Quad conversion algorithm that behaves well in terms of geometrical complexity and tessellation quality, which we use to obtain the initial quad mesh from a given triangle mesh.
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    gProximity: Hierarchical GPU-based Operations for Collision and Distance Queries
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Lauterbach, C.; Mo, Q.; Manocha, D.
    We present novel parallel algorithms for collision detection and separation distance computation for rigid and deformable models that exploit the computational capabilities of many-core GPUs. Our approach uses thread and data parallelism to perform fast hierarchy construction, updating, and traversal using tight-fitting bounding volumes such as oriented bounding boxes (OBB) and rectangular swept spheres (RSS). We also describe efficient algorithms to compute a linear bounding volume hierarchy (LBVH) and update them using refitting methods. Moreover, we show that tight-fitting bounding volume hierarchies offer improved performance on GPU-like throughput architectures. We use our algorithms to perform discrete and continuous collision detection including self-collisions, as well as separation distance computation between non-overlapping models. In practice, our approach (gProximity) can perform these queries in a few milliseconds on a PC with NVIDIA GTX 285 card on models composed of tens or hundreds of thousands of triangles used in cloth simulation, surgical simulation, virtual prototyping and N-body simulation. Moreover, we observe more than an order of magnitude performance improvement over prior GPU-based algorithms.
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    Procedural Generation of Roads
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Galin, E.; Peytavie, A.; Marechal, N.; Guerin, E.
    In this paper, we propose an automatic method for generating roads based on a weighted anisotropic shortest path algorithm. Given an input scene, we automatically create a path connecting an initial and a final point. The trajectory of the road minimizes a cost function that takes into account the different parameters of the scene including the slope of the terrain, natural obstacles such as rivers, lakes, mountains and forests. The road is generated by excavating the terrain along the path and instantiating generic parameterized models.
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    Continuum Traffic Simulation
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Sewall, J.; Wilkie, D.; Merrell, P.; Lin, M. C.
    We present a novel method for the synthesis and animation of realistic traffic flows on large-scale road networks. Our technique is based on a continuum model of traffic flow we extend to correctly handle lane changes and merges, as well as traffic behaviors due to changes in speed limit. We demonstrate how our method can be applied to the animation of many vehicles in a large-scale traffic network at interactive rates and show that our method can simulate believable traffic flows on publicly-available, real-world road data. We furthermore demonstrate the scalability of this technique on many-core systems.
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    Heat Transfer Simulation for Modeling Realistic Winter Sceneries
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Marechal, N.; Guerin, E.; Galin, E.; Merillou, S.; Merillou, N.
    This paper presents a physically based method for simulating the heat transfers between the different environmental elements to synthesize realistic winter sceneries. We simulate the snow fall over the ground, as well as the conductive, convective and radiative thermal transfers using a finite volume method according to the variations of air and dew point temperatures, the amount of snow, cloud cover and day-night cycles. Our approach takes into account phase changes such as snow melting into water or water freezing into ice.
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    Puzzle-like Collage
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Goferman, Stas; Tal, Ayellet; Zelnik-Manor, Lihi
    Collages have been a common form of artistic expression since their first appearance in China around 200 BC. Recently, with the advance of digital cameras and digital image editing tools, collages have gained popularity also as a summarization tool. This paper proposes an approach for automating collage construction, which is based on assembling regions of interest of arbitrary shape in a puzzle-like manner. We show that this approach produces collages that are informative, compact, and eye-pleasing. This is obtained by following artistic principles and assembling the extracted cutouts such that their shapes complete each other.
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    Optimizing Photo Composition
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Liu, Ligang; Chen, Renjie; Wolf, Lior; Cohen-Or, Daniel
    Aesthetic images evoke an emotional response that transcends mere visual appreciation. In this work we develop a novel computational means for evaluating the composition aesthetics of a given image based on measuring several well-grounded composition guidelines. A compound operator of crop-and-retarget is employed to change the relative position of salient regions in the image and thus to modify the composition aesthetics of the image. We propose an optimization method for automatically producing a maximally-aesthetic version of the input image. We validate the performance of the method and show its effectiveness in a variety of experiments.
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    Seamless Montage for Texturing Models
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Gal, Ran; Wexler, Yonatan; Ofek, Eyal; Hoppe, Hugues; Cohen-Or, Daniel
    We present an automatic method to recover high-resolution texture over an object by mapping detailed photographs onto its surface. Such high-resolution detail often reveals inaccuracies in geometry and registration, as well as lighting variations and surface reflections. Simple image projection results in visible seams on the surface. We minimize such seams using a global optimization that assigns compatible texture to adjacent triangles. The key idea is to search not only combinatorially over the source images, but also over a set of local image transformations that compensate for geometric misalignment. This broad search space is traversed using a discrete labeling algorithm, aided by a coarse-to-fine strategy. Our approach significantly improves resilience to acquisition errors, thereby allowing simple and easy creation of textured models for use in computer graphics.
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    Real-time Rendering of Heterogeneous Translucent Objects with Arbitrary Shapes
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Wang, Yajun; Wang, Jiaping; Holzschuch, Nicolas; Subr, Kartic; Yong, Jun-Hai; Guo, Baining
    We present a real-time algorithm for rendering translucent objects of arbitrary shapes. We approximate the scattering of light inside the objects using the diffusion equation, which we solve on-the-fly using the GPU. Our algorithm is general enough to handle arbitrary geometry, heterogeneous materials, deformable objects and modifications of lighting, all in real-time. In a pre-processing step, we discretize the object into a regular 4-connected structure (QuadGraph). Due to its regular connectivity, this structure is easily packed into a texture and stored on the GPU. At runtime, we use the QuadGraph stored on the GPU to solve the diffusion equation, in real-time, taking into account the varying input conditions: Incoming light, object material and geometry. We handle deformable objects, provided the deformation does not change the topological structure of the objects.
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    Real-time Realistic Ocean Lighting using Seamless Transitions from Geometry to BRDF
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Bruneton, Eric; Neyret, Fabrice; Holzschuch, Nicolas
    Realistic animation and rendering of the ocean is an important aspect for simulators, movies and video games. By nature, the ocean is a difficult problem for Computer Graphics: it is a dynamic system, it combines wave trains at all scales, ranging from kilometric to millimetric. Worse, the ocean is usually viewed at several distances, from very close to the viewpoint to the horizon, increasing the multi-scale issue, and resulting in aliasing problems. The illumination comes from natural light sources (the Sun and the sky dome), is also dynamic, and often underlines the aliasing issues. In this paper, we present a new algorithm for modelling, animation, illumination and rendering of the ocean, in real-time, at all scales and for all viewing distances. Our algorithm is based on a hierarchical representation, combining geometry, normals and BRDF. For each viewing distance, we compute a simplified version of the geometry, and encode the missing details into the normal and the BRDF, depending on the level of detail required. We then use this hierarchical representation for illumination and rendering. Our algorithm runs in real-time, and produces highly realistic pictures and animations.
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    Mesh Decomposition with Cross-Boundary Brushes
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Zheng, Youyi; Tai, Chiew-Lan
    We present a new intuitive UI, which we call cross-boundary brushes, for interactive mesh decomposition. The user roughly draws one or more strokes across a desired cut and our system automatically returns a best cut running through all the strokes. By the different natures of part components (i.e., semantic parts) and patch components (i.e., flatter surface patches) in general models, we design two corresponding brushes: part-brush and patch-brush. These two types of brushes share a common user interface, enabling easy switch between them. The part-brush executes a cut along an isoline of a harmonic field driven by the user-specified strokes. We show that the inherent smoothness of the harmonic field together with a carefully designed isoline selection scheme lead to segmentation results that are insensitive to noise, pose, tessellation and variation in user s strokes. Our patch-brush uses a novel facet-based surface metric that alleviates sensitivity to noise and fine details common in region-growing algorithms. Extensive experimental results demonstrate that our cutting tools can produce user-desired segmentations for a wide variety of models even with single strokes. We also show that our tools outperform the state-of-art interactive segmentation tools in terms of ease of use and segmentation quality.
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    Rendering Wave Effects with Augmented Light Field
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Oh, Se Baek; Kashyap, Sriram; Garg, Rohit; Chandran, Sharat; Raskar, Ramesh
    Ray-based representations can model complex light transport but are limited in modeling diffraction effects that require the simulation of wavefront propagation. This paper provides a new paradigm that has the simplicity of light path tracing and yet provides an accurate characterization of both Fresnel and Fraunhofer diffraction. We introduce the concept of a light field transformer at the interface of transmissive occluders. This generates mathematically sound, virtual, and possibly negative-valued light sources after the occluder. From a rendering perspective the only simple change is that radiance can be temporarily negative. We demonstrate the correctness of our approach both analytically, as well by comparing values with standard experiments in physics such as the Young s double slit. Our implementation is a shader program in OpenGL that can generate wave effects on arbitrary surfaces.
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    Mesh Snapping: Robust Interactive Mesh Cutting Using Fast Geodesic Curvature Flow
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Zhang, Juyong; Wu, Chunlin; Cai, Jianfei; Zheng, Jianmin; Tai, Xue-cheng
    This paper considers the problem of interactively finding the cutting contour to extract components from a given mesh. Some existing methods support cuts of arbitrary shape but require careful and tedious input from the user. Others need little user input however they are sensitive to user input and need a postprocessing step to smooth the generated jaggy cutting contours. The popular geometric snake can be used to optimize the cutting contour, but it cannot deal with the topology change. In this paper, we propose a geodesic curvature flow based framework to overcome all these problems. Since in many cases the meaningful cutting contour on a 3D mesh is locally shortest in the sense of some weighted curve length, the geodesic curvature flow is an ideal tool for our problem. It evolves the cutting contour to the nearby local minimum. We should mention that the previous numerical scheme, discretized geodesic curvature flow (dGCF) is too slow and has not been applied to mesh segmentation. With a careful observation to dGCF, we devise here a fast computation scheme called fast geodesic curvature flow (FGCF), which only needs to solve a smaller and easier problem. The initial cutting contour is generated by a variant of random walks algorithm, which is very fast and gives reasonable cutting result with little user input. Experiment results on the benchmark mesh segmentation data set show that our proposed framework is robust to user input and capable of producing good results reflecting geometric features and human shape perception.
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    A Data-driven Segmentation for the Shoulder Complex
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Hong, Q Youn; Park, Sang Il; Hodgins, Jessica K.
    The human shoulder complex is perhaps the most complicated joint in the human body being comprised of a set of three bones, muscles, tendons, and ligaments. Despite this anatomical complexity, computer graphics models for motion capture most often represent this joint as a simple ball and socket. In this paper, we present a method to determine a shoulder skeletal model that, when combined with standard skinning algorithms, generates a more visually pleasing animation that is a closer approximation to the actual skin deformations of the human body. We use a data-driven approach and collect ground truth skin deformation data with an optical motion capture system with a large number of markers (200 markers on the shoulder complex alone). We cluster these markers during movement sequences and discover that adding one extra joint around the shoulder improves the resulting animation qualitatively and quantitatively yielding a marker set of approximately 70 markers for the complete skeleton. We demonstrate the effectiveness of our skeletal model by comparing it with ground truth data as well as with recorded video. We show its practicality by integrating it with the conventional rendering/animation pipeline.
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    Synthesis of Responsive Motion Using a Dynamic Model
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Ye, Yuting; Liu, C. Karen
    Synthesizing the movements of a responsive virtual character in the event of unexpected perturbations has proven a difficult challenge. To solve this problem, we devise a fully automatic method that learns a nonlinear probabilistic model of dynamic responses from very few perturbed walking sequences. This model is able to synthesize responses and recovery motions under new perturbations different from those in the training examples. When perturbations occur, we propose a physics-based method that initiates motion transitions to the most probable response example based on the dynamic states of the character. Our algorithm can be applied to any motion sequences without the need for preprocessing such as segmentation or alignment. The results show that three perturbed motion clips can sufficiently generate a variety of realistic responses, and 14 clips can create a responsive virtual character that reacts realistically to external forces in different directions applied on different body parts at different moments in time.
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    Human Motion Synthesis with Optimization-based Graphs
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Ren, Cheng; Zhao, Liming; Safonova, Alla
    Continuous constrained optimization is a powerful tool for synthesizing novel human motion segments that are short. Graph-based motion synthesis methods such as motion graphs and move trees are popular ways to synthesize long motions by playing back a sequence of existing motion segments. However, motion graphs only support transitions between similar frames, and move trees only support transitions between the end of one motion segment and the start of another. In this paper, we introduce an optimization-based graph that combines continuous constrained optimization with graph-based motion synthesis. The constrained optimization is used to create a vast number of complex realistic-looking transitions in the graph. The graph can then be used to synthesize long motions with non-trivial transitions that for example allow the character to switch its behavior abruptly while retaining motion naturalness. We also propose to build this graph semi-autonomously by requiring a user to classify generated transitions as acceptable or not and explicitly minimizing the amount of required classifications. This process guarantees the quality consistency of the optimization-based graph at the cost of limited user involvement.
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    Bidirectional Search for Interactive Motion Synthesis
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Lo, Wan-Yen; Zwicker, Matthias
    We present an approach to improve the search efficiency for near-optimal motion synthesis using motion graphs. An optimal or near-optimal path through a motion graph often leads to the most intuitive result. However, finding such a path can be computationally expensive. Our main contribution is a bidirectional search algorithm. We dynamically divide the search space evenly and merge two search trees to obtain the final solution. This cuts the maximum search depth almost in half and leads to significant speedup. To illustrate the benefits of our approach, we present an interactive sketching interface that allows users to specify complex motions quickly and intuitively.
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    Shared Sampling for Real-Time Alpha Matting
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Gastal, Eduardo S. L.; Oliveira, Manuel M.
    Image matting aims at extracting foreground elements from an image by means of color and opacity (alpha) estimation. While a lot of progress has been made in recent years on improving the accuracy of matting techniques, one common problem persisted: the low speed of matte computation. We present the first real-time matting technique for natural images and videos. Our technique is based on the observation that, for small neighborhoods, pixels tend to share similar attributes. Therefore, independently treating each pixel in the unknown regions of a trimap results in a lot of redundant work. We show how this computation can be significantly and safely reduced by means of a careful selection of pairs of background and foreground samples. Our technique achieves speedups of up to two orders of magnitude compared to previous ones, while producing high-quality alpha mattes. The quality of our results has been verified through an independent benchmark. The speed of our technique enables, for the first time, real-time alpha matting of videos, and has the potential to enable a new class of exciting applications.
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    Articulated Billboards for Video-based Rendering
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Germann, Marcel; Hornung, Alexander; Keiser, Richard; Ziegler, Remo; Wuermlin, Stephan; Gross, Markus
    We present a novel representation and rendering method for free-viewpoint video of human characters based on multiple input video streams. The basic idea is to approximate the articulated 3D shape of the human body using a subdivision into textured billboards along the skeleton structure. Billboards are clustered to fans such that each skeleton bone contains one billboard per source camera. We call this representation articulated billboards.In the paper we describe a semi-automatic, data-driven algorithm to construct and render this representation, which robustly handles even challenging acquisition scenarios characterized by sparse camera positioning, inaccurate camera calibration, low video resolution, or occlusions in the scene. First, for each input view, a 2D pose estimation based on image silhouettes, motion capture data, and temporal video coherence is used to create a segmentation mask for each body part. Then, from the 2D poses and the segmentation, the actual articulated billboard model is constructed by a 3D joint optimization and compensation for camera calibration errors. The rendering method includes a novel way of blending the textural contributions of each billboard and features an adaptive seam correction to eliminate visible discontinuities between adjacent billboards textures.Our articulated billboards do not only minimize ghosting artifacts known from conventional billboard rendering, but also alleviate restrictions to the setup and sensitivities to errors of more complex 3D representations and multiview reconstruction techniques. Our results demonstrate the flexibility and the robustness of our approach with high quality free-viewpoint video generated from broadcast footage of challenging, uncontrolled environments.
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    BetweenIT: An Interactive Tool for Tight Inbetweening
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Whited, Brian; Noris, Gioacchino; Simmons, Maryann; Sumner, Robert W.; Gross, Markus; Rossignac, Jarek
    The generation of inbetween frames that interpolate a given set of key frames is a major component in the production of a 2D feature animation. Our objective is to considerably reduce the cost of the inbetweening phase by offering an intuitive and effective interactive environment that automates inbetweening when possible while allowing the artist to guide, complement, or override the results. Tight inbetweens, which interpolate similar key frames, are particularly time-consuming and tedious to draw. Therefore, we focus on automating these high-precision and expensive portions of the process. We have designed a set of user-guided semi-automatic techniques that fit well with current practice and minimize the number of required artist-gestures. We present a novel technique for stroke interpolation from only two keys which combines a stroke motion constructed from logarithmic spiral vertex trajectories with a stroke deformation based on curvature averaging and twisting warps. We discuss our system in the context of a feature animation production environment and evaluate our approach with real production data.
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    The Virtual Director: a Correlation-Based Online Viewing of Human Motion
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Assa, J.; Wolf, L.; Cohen-Or, D.
    Automatic camera control for scenes depicting human motion is an imperative topic in motion capture base animation, computer games, and other animation based fields. This challenging control problem is complex and combines both geometric constraints, visibility requirements, and aesthetic elements. Therefore, existing optimization-based approaches for human action overview are often too demanding for online computation.In this paper, we introduce an effective automatic camera control which is extremely efficient and allows online performance. Rather than optimizing a complex quality measurement, at each time it selects one active camera from a multitude of cameras that render the dynamic scene. The selection is based on the correlation between each view stream and the human motion in the scene. Two factors allow for rapid selection among tens of candidate views in real-time, even for complex multi-character scenes: the efficient rendering of the multitude of view streams, and optimized calculations of the correlations using modified CCA. In addition to the method s simplicity and speed, it exhibits good agreement with both cinematic idioms and previous human motion camera control work. Our evaluations show that the method is able to cope with the challenges put forth by severe occlusions, multiple characters and complex scenes.
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    Adding Depth to Cartoons Using Sparse Depth (In)equalities
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Sykora, D.; Sedlacek, D.; Jinchao, S.; Dingliana, J.; Collins, S.
    This paper presents a novel interactive approach for adding depth information into hand-drawn cartoon images and animations. In comparison to previous depth assignment techniques our solution requires minimal user effort and enables creation of consistent pop-ups in a matter of seconds. Inspired by perceptual studies we formulate a custom tailored optimization framework that tries to mimic the way that a human reconstructs depth information from a single image. Its key advantage is that it completely avoids inputs requiring knowledge of absolute depth and instead uses a set of sparse depth (in)equalities that are much easier to specify. Since these constraints lead to a solution based on quadratic programming that is time consuming to evaluate we propose a simple approximative algorithm yielding similar results with much lower computational overhead. We demonstrate its usefulness in the context of a cartoon animation production pipeline including applications such as enhancement, registration, composition, 3D modelling and stereoscopic display.
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    Printed Patterns for Enhanced Shape Perception of Papercraft Models
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Xue, Su; Chen, Xuejin; Dorsey, Julie; Rushmeier, Holly
    Papercraft models can serve as inexpensive prototypes in shape design applications. However, in making the models some geometric detail is necessarily lost, and artificial creases may be visible, thereby limiting the utility of these models. To compensate for these practical limitations, we introduce the use of printed patterns on papercraft models to enhance the perception of the shape they are intended to represent. We propose pattern generation schemes that modulate the sizes, directions, and densities of glyphs of patterns based on geometric attributes. We present a psychophysical experiment designed to explore the effect that printed patterns have on the perception of the papercraft model shapes. We find that models with printed patterns are perceived to represent the intended shape more accurately, and, further, that the type of printed pattern has an impact on the perceived shape.
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    Consensus Skeleton for Non-rigid Space-time Registration
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Zheng, Q.; Sharf, A.; Tagliasacchi, A.; Chen, B.; Zhang, H.; Sheffer, A.; Cohen-Or, D.
    We introduce the notion of consensus skeletons for non-rigid space-time registration of a deforming shape. Instead of basing the registration on point features, which are local and sensitive to noise, we adopt the curve skeleton of the shape as a global and descriptive feature for the task. Our method uses no template and only assumes that the skeletal structure of the captured shape remains largely consistent over time. Such an assumption is generally weaker than those relying on large overlap of point features between successive frames, allowing for more sparse acquisition across time. Building our registration framework on top of the low-dimensional skeleton-time structure avoids heavy processing of dense point or volumetric data, while skeleton consensusization provides robust handling of incompatibilities between per-frame skeletons. To register point clouds from all frames, we deform them by their skeletons, mirroring the skeleton registration process, to jump-start a non-rigid ICP. We present results for non-rigid space-time registration under sparse and noisy spatio-temporal sampling, including cases where data was captured from only a single view.
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    Electors Voting for Fast Automatic Shape Correspondence
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Kin-Chung Au, Oscar; Tai, Chiew-Lan; Cohen-Or, Daniel; Zheng, Youyi; Fu, Hongbo
    This paper challenges the difficult problem of automatic semantic correspondence between two given shapes which are semantically similar but possibly geometrically very different (e.g., a dog and an elephant). We argue that the challenging part is the establishment of a sparse correspondence and show that it can be efficiently solved by considering the underlying skeletons augmented with intrinsic surface information. To avoid potentially costly direct search for the best combinatorial match between two sets of skeletal feature nodes, we introduce a statistical correspondence algorithm based on a novel voting scheme, which we call electors voting. The electors are a rather large set of correspondences which then vote to synthesize the final correspondence. The electors are selected via a combinatorial search with pruning tests designed to quickly filter out a vast majority of bad correspondence. This voting scheme is both efficient and insensitive to parameter and threshold settings. The effectiveness of the method is validated by precision-recall statistics with respect to manually defined ground truth. We show that high quality correspondences can be instantaneously established for a wide variety of model pairs, which may have different poses, surface details, and only partial semantic correspondence.
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    Sketching Clothoid Splines Using Shortest Paths
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Baran, Ilya; Lehtinen, Jaakko; Popovic, Jovan
    Clothoid splines are gaining popularity as a curve representation due to their intrinsically pleasing curvature, which varies piecewise linearly over arc length. However, constructing them from hand-drawn strokes remains difficult. Building on recent results, we describe a novel algorithm for approximating a sketched stroke with a fair (i.e., visually pleasing) clothoid spline. Fairness depends on proper segmentation of the stroke into curve primitives - lines, arcs, and clothoids. Our main idea is to cast the segmentation as a shortest path problem on a carefully constructed weighted graph. The nodes in our graph correspond to a vastly overcomplete set of curve primitives that are fit to every subsegment of the sketch, and edges correspond to transitions of a specified degree of continuity between curve primitives. The shortest path in the graph corresponds to a desirable segmentation of the input curve. Once the segmentation is found, the primitives are fit to the curve using non-linear constrained optimization. We demonstrate that the curves produced by our method have good curvature profiles, while staying close to the user sketch.
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    Inverse Procedural Modeling by Automatic Generation of L-systems
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) St ava, O.; Benes, B.; Mech, R.; Aliaga, D. G.; Kristof, P.
    We present an important step towards the solution of the problem of inverse procedural modeling by generating parametric context-free L-systems that represent an input 2D model. The L-system rules efficiently code the regular structures and the parameters represent the properties of the structure transformations. The algorithm takes as input a 2D vector image that is composed of atomic elements, such as curves and poly-lines. Similar elements are recognized and assigned terminal symbols of an L-system alphabet. The terminal symbols position and orientation are pair-wise compared and the transformations are stored as points in multiple 4D transformation spaces. By careful analysis of the clusters in the transformation spaces, we detect sequences of elements and code them as L-system rules. The coded elements are then removed from the clusters, the clusters are updated, and then the analysis attempts to code groups of elements in (hierarchies) the same way. The analysis ends with a single group of elements that is coded as an L-system axiom. We recognize and code branching sequences of linearly translated, scaled, and rotated elements and their hierarchies. The L-system not only represents the input image, but it can also be used for various editing operations. By changing the L-system parameters, the image can be randomized, symmetrized, and groups of elements and regular structures can be edited. By changing the terminal and non-terminal symbols, elements or groups of elements can be replaced.
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    Hybrid Simulation of Miscible Mixing with Viscous Fingering
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Shin, Seung-Ho; Kam, Hyeong Ryeol; Kim, Chang-Hun
    By modeling mass transfer phenomena, we simulate solids and liquids dissolving or changing to other substances. We also deal with the very small-scale phenomena that occur when a fluid spreads out at the interface of another fluid. We model the pressure at the interfaces between fluids with Darcy s Law and represent the viscous fingering phenomenon in which a fluid interface spreads out with a fractal-like shape. We use hybrid grid-based simulation and smoothed particle hydrodynamics (SPH) to simulate intermolecular diffusion and attraction using particles at a computable scale. We have produced animations showing fluids mixing and objects dissolving.
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    A Hybrid Approach to Multiple Fluid Simulation using Volume Fractions
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Kang, Nahyup; Park, Jinho; Noh, Junyong; Shin, Sung Yong
    This paper presents a hybrid approach to multiple fluid simulation that can handle miscible and immiscible fluids, simultaneously. We combine distance functions and volume fractions to capture not only the discontinuous interface between immiscible fluids but also the smooth transition between miscible fluids. Our approach consists of four steps: velocity field computation, volume fraction advection, miscible fluid diffusion, and visualization. By providing a combining scheme between volume fractions and level set functions, we are able to take advantages of both representation schemes of fluids. From the system point of view, our work is the first approach to Eulerian grid-based multiple fluid simulation including both miscible and immiscible fluids. From the technical point of view, our approach addresses the issues arising from variable density and viscosity together with material diffusion. We show that the effectiveness of our approach to handle multiple miscible and immiscible fluids through experiments.
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    Tetrahedral Embedded Boundary Methods for Accurate and Flexible Adaptive Fluids
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Batty, Christopher; Xenos, Stefan; Houston, Ben
    When simulating fluids, tetrahedral methods provide flexibility and ease of adaptivity that Cartesian grids find difficult to match. However, this approach has so far been limited by two conflicting requirements. First, accurate simulation requires quality Delaunay meshes and the use of circumcentric pressures. Second, meshes must align with potentially complex moving surfaces and boundaries, necessitating continuous remeshing. Unfortunately, sacrificing mesh quality in favour of speed yields inaccurate velocities and simulation artifacts. We describe how to eliminate the boundary-matching constraint by adapting recent embedded boundary techniques to tetrahedra, so that neither air nor solid boundaries need to align with mesh geometry. This enables the use of high quality, arbitrarily graded, non-conforming Delaunay meshes, which are simpler and faster to generate. Temporal coherence can also be exploited by reusing meshes over adjacent timesteps to further reduce meshing costs. Lastly, our free surface boundary condition eliminates the spurious currents that previous methods exhibited for slow or static scenarios. We provide several examples demonstrating that our efficient tetrahedral embedded boundary method can substantially increase the flexibility and accuracy of adaptive Eulerian fluid simulation.
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    Improved Variational Guiding of Smoke Animations
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Nielsen, Michael B.; Christensen, Brian B.
    Smoke animations are hard to art-direct because simple changes in parameters such as simulation resolution often lead to unpredictable changes in the final result. Previous work has addressed this problem with a guiding approach which couples low-resolution simulations - that exhibit the desired flow and behaviour - to the final, high-resolution simulation. This is done in such a way that the desired low frequency features are to some extent preserved in the high-resolution simulation. However, the steady (i.e. constant) guiding used often leads to a lack of sufficiently high detail, and employing time-dependent guiding is expensive because the matrix of the resulting set of equations needs to be recomputed at every iteration. We propose an improved mathematical model for Eulerian-based simulations which is better suited for dynamic, time-dependent guiding of smoke animations through a novel variational coupling of the low- and high-resolution simulations. Our model results in a matrix that does not require re-computation when the guiding changes over time, and hence we can employ time-dependent guiding more efficiently both in terms of storage and computational requirements. We demonstrate that time-dependent guiding allows for more high frequency detail to develop without losing correspondence to the low resolution simulation. Furthermore, we explore various artistic effects made possible by time-dependent guiding.
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    Perceptually-motivated Real-time Temporal Upsampling of 3D Content for High-refresh-rate Displays
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Didyk, Piotr; Eisemann, Elmar; Ritschel, Tobias; Myszkowski, Karol; Seidel, Hans-Peter
    High-refresh-rate displays (e. g., 120 Hz) have recently become available on the consumer market and quickly gain on popularity. One of their aims is to reduce the perceived blur created by moving objects that are tracked by the human eye. However, an improvement is only achieved if the video stream is produced at the same high refresh rate (i. e. 120 Hz). Some devices, such as LCD TVs, solve this problem by converting low-refresh-rate content (i. e. 50 Hz PAL) into a higher temporal resolution (i. e. 200 Hz) based on two-dimensional optical flow.In our approach, we will show how rendered three-dimensional images produced by recent graphics hardware can be up-sampled more efficiently resulting in higher quality at the same time. Our algorithm relies on several perceptual findings and preserves the naturalness of the original sequence. A psychophysical study validates our approach and illustrates that temporally up-sampled video streams are preferred over the standard low-rate input by the majority of users. We show that our solution improves task performance on high-refresh-rate displays.
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    Scalable Height Field Self-Shadowing
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Timonen, Ville; Westerholm, Jan
    We present a new method suitable for general purpose graphics processing units to render self-shadows on dynamic height fields under dynamic light environments in real-time. Visibility for each point in the height field is determined as the exact horizon for a set of azimuthal directions in time linear in height field size and the number of directions. The surface is shaded using the horizon information and a high-resolution light environment extracted on-line from a high dynamic range cube map, allowing for detailed extended shadows. The desired accuracy for any geometric content and lighting complexity can be matched by choosing a suitable number of azimuthal directions. Our method is able to represent arbitrary features of both high- and low-frequency, unifying hard and soft shadowing. We achieve 23 fps on 1024x1024 height fields with 64 azimuthal directions under a 256x64 environment lighting on an Nvidia GTX 280 GPU.
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    Motion Blur for EWA Surface Splatting
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Heinzle, Simon; Wolf, Johanna; Kanamori, Yoshihiro; Weyrich, Tim; Nishita, Tomoyuki; Gross, Markus
    This paper presents a novel framework for elliptical weighted average (EWA) surface splatting with time-varying scenes. We extend the theoretical basis of the original framework by replacing the 2D surface reconstruction filters by 3D kernels which unify the spatial and temporal component of moving objects. Based on the newly derived mathematical framework we introduce a rendering algorithm that supports the generation of high-quality motion blur for point-based objects using a piecewise linear approximation of the motion. The rendering algorithm applies ellipsoids as rendering primitives which are constructed by extending planar EWA surface splats into the temporal dimension along the instantaneous motion vector. Finally, we present an implementation of the proposed rendering algorithm with approximated occlusion handling using advanced features of modern GPUs and show its capability of producing motion-blurred result images at interactive frame rates.
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    Two-Colored Pixels
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Pavic, Darko; Kobbelt, Leif
    In this paper we show how to use two-colored pixels as a generic tool for image processing. We apply two-colored pixels as a basic operator as well as a supporting data structure for several image processing applications. Traditionally, images are represented by a regular grid of square pixels with one constant color each. In the two-colored pixel representation, we reduce the image resolution and replace blocks of N x N pixels by one square that is split by a (feature) line into two regions with constant colors. We show how the conversion of standard mono-colored pixel images into two-colored pixel images can be computed efficiently by applying a hierarchical algorithm along with a CUDA-based implementation. Two-colored pixels overcome some of the limitations that classical pixel representations have, and their feature lines provide minimal geometric information about the underlying image region that can be effectively exploited for a number of applications. We show how to use two-colored pixels as an interactive brush tool, achieving realtime performance for image abstraction and non-photorealistic filtering. Additionally, we propose a realtime solution for image retargeting, defined as a linear minimization problem on a regular or even adaptive two-colored pixel image. The concept of two-colored pixels can be easily extended to a video volume, and we demonstrate this for the example of video retargeting.
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    Fast High-Dimensional Filtering Using the Permutohedral Lattice
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Adams, Andrew; Baek, Jongmin; Davis, Myers Abraham
    Many useful algorithms for processing images and geometry fall under the general framework of high-dimensional Gaussian filtering. This family of algorithms includes bilateral filtering and non-local means. We propose a new way to perform such filters using the permutohedral lattice, which tessellates high-dimensional space with uniform simplices. Our algorithm is the first implementation of a high-dimensional Gaussian filter that is both linear in input size and polynomial in dimensionality. Furthermore it is parameter-free, apart from the filter size, and achieves a consistently high accuracy relative to ground truth (> 45 dB). We use this to demonstrate a number of interactive-rate applications of filters in as high as eight dimensions.
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    Reinterpretable Imager: Towards Variable Post-Capture Space, Angle and Time Resolution in Photography
    (The Eurographics Association and Blackwell Publishing Ltd, 2010) Agrawal, Amit; Veeraraghavan, Ashok; Raskar, Ramesh
    We describe a novel multiplexing approach to achieve tradeoffs in space, angle and time resolution in photography. We explore the problem of mapping useful subsets of time-varying 4D lightfields in a single snapshot. Our design is based on using a dynamic mask in the aperture and a static mask close to the sensor. The key idea is to exploit scene-specific redundancy along spatial, angular and temporal dimensions and to provide a programmable or variable resolution tradeoff among these dimensions. This allows a user to reinterpret the single captured photo as either a high spatial resolution image, a refocusable image stack or a video for different parts of the scene in post-processing.A lightfield camera or a video camera forces a-priori choice in space-angle-time resolution. We demonstrate a single prototype which provides flexible post-capture abilities not possible using either a single-shot lightfield camera or a multi-frame video camera. We show several novel results including digital refocusing on objects moving in depth and capturing multiple facial expressions in a single photo.