Fig. 5.

Reeb graph of a simple branching structure extracted with the height function. Vertices are marked in red. Edges are marked in green if the distance between two vertices is larger than two pixels. At these center points, diameter measurements can be derived without interpolation of a curve between two vertices. The level sets were extracted at intervals of one pixel. The robustness of the Reeb graph to small disturbances of the boundary is demonstrated in the example in Fig. 3.