Skeleton extraction by mesh contraction

Abstract

Curve-skeleton is a very useful 1D structure to abstract the geometry and topology of a 3D object. Extraction of curve-skeletons is a fundamental problem in computer graphics, visualization, image processing and computer vision.There many useful applications including virtual colonoscopies, collision detection, computer animation, surface reconstruction and shape matching etc. In the literature [1][2], most previous methods require a volumetric discrete representation of the input model. However, transforming them into volumetric representations may raise discretization error in both geometry and connectivity.In this work [3], we propose a novel technique to extract skeletons directly from the mesh domain without requirement of volumetric discretization. Our approach (Figure 1) consists of three main steps: 1) mesh contraction, 2) connectivity surgery and 3) centeredness refinement. First, we contract a given mesh into a zero-volume skeletal shape by applying an iterative Laplacian smoothing procedure [4] with global positional constraints. Second, we execute a connectivity surgery procedure to progressively convert the contracted mesh into a 1D curve skeleton. Finally, to ensure its centeredness within the mesh, we refine the skeleton by moving each skeletal node to the center of its corresponding mesh region. In contrast to previous work, our approach has the following advantages: 1) our extracted skeleton is ensured to be homotopic to the original object, 2) it is inherently robust against noise disturbance (see Figure 2) and avoids volumetric discretization errors, and 3) the method is very fast and it is rotation invariant, and pose insensitive (Figure 3).

An interactive editor for curve-skeletons: SkeletonLab

“…This approach, although less robust than [17,23,11] presents heuristics for collapsing spurious branches and closing loops whenever two terminal nodes have intersecting maximal balls, which are beneficial for the resulting structure. A particularly notable example of point cloud based methods is the work of Huang et al [14], which allows to obtain high quality skeletons from raw and potentially incomplete scans by using the L1-median operator.…”

Numerical assessment of airflow and inhaled particles attributes in obstructed pulmonary system

“…In order to apply mesh contraction, we employ the Laplacian mesh processing scheme presented in [29]. For the shake of self-completeness, we provide a short overview of the method.…”

Automatic Conversion of Human Mesh into Skeleton Animation by Using Kinect Motion

“…In short, a significant amount of research has proposed different methods for extracting skeleton from the mesh [4], [7], [8]. However, most of recent research has focused only to draw the line-skeleton in a given model.…”

“…The 1D curve-skeleton is derived from the contracted mesh through edge contraction operation. The methods of Au et al [4] used as starting point of the contracting mesh model.…”