;  
Skeleton Extraction by Mesh Contraction

ACM Transaction on Graphics (Proceedings of SIGGRAPH 2008)

Oscar Kin-Chung Au1     Chiew-Lan Tai1     Hung-Kuo Chu2     Daniel Cohen-Or3     Tong-Yee Lee2

Hong Kong University of Science &Technology
2
National Cheng Kung University
3Tel Aviv University

Teaser: Our method extracts a 1D skeletal shape by performing geometry contraction using constrained Laplacian smoothing. Left to right are the original mesh and the results of the contraction after 1, 2 and 3 iterations. Faces with zero area are drawn in red. The ray-traced image shows the final skeleton after performing connectivity surgery and embedding refinement.

Abstract
Extraction of curve-skeletons is a fundamental problem with many applications in computer graphics and visualization. In this paper, we present a simple and robust skeleton extraction method based on mesh contraction. The method works directly on the mesh domain, without pre-sampling the mesh model into a volumetric representation. The method first contracts the mesh geometry into a zero-volume skeletal shape by applying implicit Laplacian smoothing with global positional constraints. The contraction does not alter the mesh connectivity and retains the key features of the original mesh. The contracted mesh is then converted into a 1D curve-skeleton through a connectivity surgery process to remove all the collapsed faces while preserving the shape of the contracted mesh and the original topology. The centeredness of the skeleton is refined by exploiting the induced skeleton-mesh mapping. The contraction process generates valuable information about the object's geometry, in particular, the skeleton-vertex correspondence and the local thickness, which are useful for various applications. We demonstrate its effectiveness in mesh segmentation and skinning animation.
Paper
Video
Youtube video
Demo Program
zipped executable code with models
zipped source code
Examples

page-1 (old) page-2 (old)
BibTeX
@ARTICLE{Au:2008,
    author = {Oscar Kin-Chung Au and Chiew-Lan Tai and Hung-Kuo Chu and Daniel Cohen-Or and Tong-Yee Lee},
    title = {Skeleton Extraction by Mesh Contraction},
    journal = {ACM Trans. Graph.},
    year = {2008},
    volume = {27},
    number = {3},
}
ipstat