Segmentation of collagen fiber bundles in 3D by waterfall on orientations

The micro-structure of bovine leather samples is imaged three dimensionally using micro-computed tomography. We report on the first algorithm for automatic segmentation of ""typical"" elements of this multiscale structure based on the reconstructed 3D images. In spite of the scales being hardly separable, a coarse segmentation and a finer substructure can be derived in a consistent way. For preprocessing, an adapted morphological shock filter is suggested. The segmentation algorithm for the coarse fiber bundles exploits the watershed transform and the waterfall paradigm on orientation. The fine substructure is reconstructed from core parts within the bounds given by the coarse bundles.