Velcro Surfaces

Even though methods based on the use of deformable models have become prevalent, the quality of their output depends critically on the model's initial state. The issue of initializing such models, however, has not received much attention even though it is often key to the implementation of a truly useful system.We therefore present a new approach to segmentation of three-dimensional (3-D) shapes that initializes and then optimizes a 3-D surface model given only the data and a very small number of 3-D seed points and corresponding surface normals. This is a valuable capability for medical, robotic, and cartographic applications where such seed points can be naturally supplied. In effect, the surface model is clamped onto the object boundary in a manner reminiscent of Velcro being closed. Applications of the developed method to stereo imagery and to volumetric medical data are demonstrated.