This is documentation of an archived release.
For documentation on the current version, please check Knowledge Base.

Preferences of Automated Pole Detection

This page describes only the parameters and preferences of Automated Pole Detection.
Full documentation about concept, workflow and sidebar, see Automated Feature Extraction. General concepts of Detectors Preferences, see Preferences of Detectors.

Cell size, Cell points min, Cell size overlap and Height min
Scan the point cloud and exclude “pole-free” cells.

Cell size hist and Pole points min
Detect candidate locations where pole potentially can be situated (point's density peak is expected at the location of a pole).

Diameter max
Exclude candidate locations belonging to big vertical structures like facades of the buildings or fences.

Height min and Height max
Allows to exclude candidates having Z range outside expected interval of a pole height.

Slice thickness and Pole gap max
Every candidate pole is divided into horizontal slices. Percentage of consequent empty slices allowed in a pole. If exceeded only the “best” (biggest, closest to the ground) part is considered to be a pole candidate in further processing.

Min circle ratio and Diam exceeded
The slices of a pole should be circular; minimum circle ratio defines what is considered to be a “good” circle, percentage of diameter exceeded defines how many 'bad' slices are allowed for a pole.

Diameter min, Diameter max
Exclude candidate locations for which best fitting diameter does not belong to the required interval.

Slice thickness, Slice overlap and Mask matching
Consequent slices of a pole are expected to be similar to each other, mask matching parameter defines the expected similarity.

Proximity
Defines maximum distance from initial candidate pole to the points which can also belong to the pole to get elements which are attached to the pole like traffic signs, lights etc.

Ground margin
If the terrain is not exactly flat next to the pole (high grass or other noise next to pole) the ground margin defines “thickness of the ground”.

Remove poles not on the ground: Ground offset
Together with ground margin these parameters remove “flying” poles. Maximum distance from the bottom of the candidate pole to the ground is ground margin plus ground offset.

Remove trees: Min height stalk, Tree slice height and Min ratio trees slices
Parameters defining which poles are actually trees and removing them from the pole candidates.

Remove signs: Max sign thickness, Min diam sign and Max sign height
Parameters defining which poles are actually traffic signs and removing them from the pole candidates.

Fence slice max
Removes poles belonging to fences.

Examples

  1. Small pole close to the big one might not be found as it will not show a density peak at the location of a smaller pole. Parameter to change to have higher probability to find the small pole as well: Cell size hist.
 
Last modified:: 2019/05/07 12:49