Automatic Reconstruction of Unstructured 3 DData : Combining a Medial

This paper presents a new method that combines a medial axis and implicit surfaces in order to reconstruct a 3D solid from an unstructured set of points scattered on the object's surface. The representation produced is based on iso-surfaces generated by skeletons, and is a particularly compact way of deening a smooth free-form solid. The method is based on the minimisation of an energy representing a \distance" between the set of data points and the iso-surface, resembling previous reserach 19. Initialisation, however, is more robust and eecient since there is computation of the medial axis of the set of points. Instead of subdividing existing skeletons in order to reene the object's surface, a new reconstruction algorithm progressively selects skeleton-points from the pre-computed medial axis using an heuristic principle based on a \local energy" criterion. This drastically speeds up the reconstruction process. Moreover, using the medial axis allows reconstruction of objects with complex topology and geometry, like objects that have holes and branches or that are composed of several connected components. This process is fully automatic. The method has been successfully applied to both synthetic and real data.