The segmentation tool allows for a distinction of crown area based on an edge segmentation and result in vectorized tree segments (
Höfle et al. 2012). A normalized Digital Surface Model (nDSM) is required as input.
If the crowns of the nDSM show a high roughness (especially if scanned under leaf-off conditions), a Gauss filter can be activated. The Gauss filter shapes the crowns more convex. The segment edges result from a skeletonization of the concave areas of the nDSM (a depression between trees).
To limit the segmentation to vegetation, the minimum height threshold can be set. According to the window size of the curvature calculation, segments of fine structures ("over-segmentation") or large-scale structures ("under-segmentation") are reachable.