Extracting medial curves on 3D images

This paper proposes a 2-subfield thinning algorithm for extracting medial curves on 3D binary images where the set of all voxels of an image is partitioned into two isometric subsets and the algorithm works alternatively on each subset at a time. The thinning algorithm is proved to preserve topology. An algorithm for verifying the topology soundness of thinning algorithms should be established to simplicity the procedure for preparing such proofs.