Sewing faces: a topological reconstruction of 6-connected objects bounding surfaces in 3D digital images

We present a new algorithm, called "Sewing Faces". From 3d images defined by a block of voxels, this algorithm based on a contour following reconstructs bounding surfaces of 6-connected objects. A bounding surface is a set of faces shared by two voxels: one belonging to the object, the other one belonging to its complement. The topological model used to represent these surfaces consists in a set of such faces which are sewed together in such a way that they define a closed surface, or skin. The reconstructed surface can then be embedded into space to give a surface mesh. We show that the complexity of the algorithm is linear in time and space relatively to the number of faces of the skin.