Spine slices are shown for an experimental volume with fraction of holes = 0.44. (a)–(f): Slices in-plane with holes. (g)–(l) Slices transverse to holes. From left to right: ground truth, no hole filling, sticks hole filling, nearest neighbor hole filling, Gaussian-weighted hole filling (kernel size 3), Gaussian-weighted hole filling (kernel size 5). The in-plane slice without hole filling is black because it consists entirely of holes.