Three-dimensional skeletonization using distance transform

Skeletonization as a tool for quantitative analysis of three-dimensional (3D) images is becoming more important, as they are more common in a number of application fields, especially in biomedical tomographic images at different scales. Here we propose a method, which computes both surface and curve skeletons of 3D binary images.. The distance transform algorithm is applied to reduce a 3D object to a 2D surface skeleton, and then to a 1D curve skeleton in two phases. Ln surface skeletonization, 6-connectivity is used in distance transform; while in curve skeletonization, 18-connectivity is used in computing distance transform. Some examples are discussed to illustrate the algorithm.