4th february 2003 animating scanned human models joão fradinho oliveira* animating scanned human...
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4th February 2003
Animating Scanned Human Models
João Fradinho Oliveira*Animating Scanned Human Models
Dongliang Zhang** Bernard Buxton*Bernhard Spanlang*
* Department of Computer Science, University College London
** CAD/CAM CenterHong Kong University of Science & Technology
4th February 2003
Animating Scanned Human Models
1 - Feature extraction/segmentation
2 - Building the skeleton
3 - LOD to reduce computation
4 - Mapping skin to skeleton/surface growing
5 - Motion capture DEMO & Acknowledgements
Overview
Background
Conclusion
4th February 2003
Animating Scanned Human Models
1 - Feature extraction/segmentation
2 - Building the skeleton
3 - LOD to reduce computation
4 - Mapping skin to skeleton/surface growing
5 - Motion capture DEMO & Acknowledgements
Overview
Background
Conclusion
4th February 2003
Animating Scanned Human Models
• Standard layered approach Control skeleton + skin e.g. [Sun W et al.] Layered Animation of Captured Data, Animation and Simulation’99
• Control skeleton has BVH hierarchy• Motivation to create skeleton automatically
Background
Medial axis,Convex Hull Library
Control skeleton
4th February 2003
Animating Scanned Human Models
1 - Feature extraction/segmentation
[Dekker et al.] Building Symbolic Information for 3D Human Body Modelling Range DataProceedings of the 2nd International Conference on 3-D Digital Imaging and modelling, IEEE Computer Society
Octree/horizontal slices
4th February 2003
Animating Scanned Human Models
1 - Feature extraction/segmentation
Projected contour approach/local maxima
Slice approach(binning, changes inDepth)
6 groups of centroids2 levels/phases of featureextraction
4th February 2003
Animating Scanned Human Models
2 - Building the skeleton
centroids centroids +landmarks
closest centroidsto landmarks
skeleton
4th February 2003
Animating Scanned Human Models
3 - LOD to reduce computation
135 099 triangles ---------------------------- 4999 triangles
67595 vertices -------------------------------- 2535 vertices
4th February 2003
Animating Scanned Human Models
4 – Mapping skin to skeleton/surface growing
• Use skeleton + bisector planes, for skin mapping
• Volume queries, user placement of separation planes
A - Select triangle closest to endpoints of skeleton
B - Select connected triangles that are behind separation planes
4th February 2003
Animating Scanned Human Models
4 – Mapping skin to skeleton/surface growing
4th February 2003
Animating Scanned Human Models
4 – Mapping skin to skeleton/surface growing
Bi-sector separation plane
Landmark constrained separation plane
4th February 2003
Animating Scanned Human Models
4 – Mapping skin to skeleton/surface growing
STEP 1 – select connected triangles after plane & below small vertical offset of landmarke.g. smallest edge length of model /will also work with a zero offset in all models
4th February 2003
Animating Scanned Human Models
4 – Mapping skin to skeleton/surface growing
STEP 2 – select connected triangles above the vertical offset of the landmark &behind the landmark constrained plane
4th February 2003
Animating Scanned Human Models
4 – Mapping skin to skeleton/surface growing
mapped skin result
4th February 2003
Animating Scanned Human Models
4 – Mapping skin to skeleton/surface growing
W = u
Rigid transformation vs Soft transformation
Mapping parameters/ vertex attributes
4th February 2003
Animating Scanned Human Models
4 – Mapping skin to skeleton/surface growing
Two-link structure
Multi-link structure[Weber J.] Run-Time Skin deformation, Game Developers Conference 2000
More on deformation constraints:
4th February 2003
Animating Scanned Human Models
5 - Motion capture DEMO & Acknowledgements
• Hamamatsu Photonics UK• Prof. Mel Slater, EPSRC grant GR/M46082/01 (UK)• Fundacao Calouste Gulbenkian (Portugal)• Ministerio da Ciencia e Tecnologia (Portugal), JNICT/PRAXIS XXI