DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Automatic Posing of a Meshed Human Model Using Point Clouds Lei Wang Joint work with Tamal K. Dey, Huamin Wang and Bo Fu
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Problem Statement Low-end scanning devices are becoming popular. But quality of their output… Reconstruct from problematic human scans by deforming a prior high quality template mesh
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Related Work Model-based Registration Parametric human body models Registration without a Model Manual intervention Non-rigid registration by nonlinear optimization Isometric deformations: keep geodesic distance unchanged
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Our Method: Outline computing correspondences posingoutput
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Computing Correspondences
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Computing Correspondences The Global Point Signature (GPS) framework by [Rustamov 2007]: Apply Gaussian-weighted Graph Laplacian on the adjacency graph of input point cloud Graph Laplacian GPS in dimension 1, 2 and 3
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Computing Correspondences GPS is invariant under isometric deformation We choose only the first three eigenfunctions
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Computing Correspondences Correspondences are expanded from 5 extremums of aligned GPS embeddings
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Posing Template Mesh Formulated as an energy minimization problem: is the internal energy of template mesh ○ measures difference between template and the point cloud Solved by Invertible FEM [Irving et al. 2004]
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING It has two stages Point cloud alignment: deformed by input point cloud Posing Template Mesh Initial alignment: deformed by correspondence
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Posing Template Mesh For efficiency, posing is performed on a simplified template mesh, called control mesh Deformed template is recovered by Mean Value Coordinates [Ju et al. 2005], i.e., weighted sum of the control mesh
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Results
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Results
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Results
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Results (a) input scan (b) our method (c) SCAPE
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Results can be used to control the body size
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Supplementary Video
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Discussion An automatic approach to align a detailed template mesh with human point clouds in different poses Robust to noise and occlusions Sensitive to topological change Can not handle details like fingers Does not run in real-time
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING Q & A Thank you!