Fig. 6
From: TopoRoot: a method for computing hierarchy and fine-grained traits of maize roots from 3D imaging
Illustration of the heuristic for inferring hierarchy. A The input skeleton \(S\) with only the stem region labelled (blue). B The first stage associates each parent branch with one of its children branches (indicated by arrows). The numbers are the depth \(d(b)\) stored at each branch \(b\), an intermediate quantity used to determine the parent–child association. C The second stage assigns hierarchy levels (shown as numbers and grouped by colors) to each skeleton branch segment based on the parent–child association. These level labels make up the hierarchy \(H\)