3D Reconstruction from Micro-CT Slices for Non-Destructive Viewing inside a Fossil

Fossils undergo atypical taphonomic and diagenetic deformations while they are being formed. The internal structure of such deformities requires deep and thorough paleontological investigation, and hence demands a reliable digital reconstruction. However, non-destructive study of fossils using conventional medical imaging fails to preserve the internal tissue structure and suffers from slow computation. This has motivated us to pick up this maiden problem and come up with an efficient technique that can digitally reconstruct a fossil from a sequence of 2D micro computerized tomographic scan (micro-CT) slices. The proposed technique is marked with a couple of novel concepts. First, the components on each slice are represented by their encoded boundaries, which are smoothed to get rid of their jagged nature. For this, the notion of majority code is introduced, followed by bilinear interpolation to make up the inter-slice gaps. Second, for various tasks such as intersection, cutting, joining, and the like, we consider the thinnest digital plane. The reconstructed volume being a well-defined set of voxels, admits quick operations with such planes, thereby expediting the procedure invoked by the user. Furthermore, as the surface of the reconstructed volume is well-formed, the marching cube method can easily be used for 3D mesh creation and for visualization. The reconstruction algorithm runs in a time linear in the number of slices and is found to have 98% accuracy in reconstruction with preservation of both bone and tissue structures, as validated by professional paleontologists.