Trimble Business Center

Tip #141: Extract Classified Interior Point Cloud Regions

By Erin Johnson posted 02-26-2021 09:20

  

Good morning TBC’ers! Have you ever scanned the inside of a building and wished there was a way to automatically classify an indoor scan dataset? Well, the Extract Classified Point Cloud Regions command has been updated in TBC v5.40 to differentiate between outdoor and indoor scan datasets. The indoor classification extracts the following classes:

 
  • Walls: Extracts vertical structures that enclose a space as part of the building envelope. The extraction is intended to work only with vertical walls (flat or curved). Inclined walls are not extracted.
  • Floor: Extracts a man-made flat surface accessible by a walking person. In industrial environments, it is usually concrete. In the case of multiple floors, only the lowest one will be extracted.
  • Grated floor: Extracts a man-made floor composed of a regularly spaced collection of essentially identical, parallel, elongated elements. In an industrial environment, grated floors are typically metallic and prevent access through an opening while permitting communication or ventilation.
  • Ceiling: Extracts upper interior surface of a room or other similar compartment. The extraction is intended to work only with a flat ceiling. Both grating and concrete ceilings will be extracted.
 

To extract interior point cloud regions, follow these steps:

 
1. Navigate to the Point Clouds Ribbon and select Extract Classified Point Cloud Regions under Regions:

 
2. Set the Classification type to Indoor from the drop-down list:

 
3. Click in the Point cloud region selection field. Then, in the Project Explorer or a graphic view, select the point cloud region(s) from which you want to extract classified regions:

 

Or, select Point Cloud > Selection > Rectangle Select (or press F5) or Point Cloud > Selection > Polygon Select (or press F6) and draw your scan point selection in a graphic view.

 
4. Optionally, if you want to specify that only a single region be created for a classification when multiple features are found (instead of one region per feature), check the Create one new region per class checkbox:

 
5. Check the Classes to extract checkbox for each class that you want to extract:

 
6. Click the Extract button at the bottom of the command pane:

 

The status of the extraction process is displayed at the bottom of the TBC window. When the process is complete, the newly extracted classified point cloud regions are displayed in the Project Explorer. The regions display in the graphic views in the color defined for the region (for example, the Ceiling regions are green by default). 

 

You can now do any of the following:

  • Use the View Filter Manager to hide or show any classified or non-classified point cloud regions.
  • Edit a classified point cloud region by right-clicking it in the Project Explorer and selecting Properties. You can change the region’s name, classification, color, and rendering properties (for example, change the classification for a region that was misclassified during the automatic classification process).
  • Merge classified point cloud regions (for example, merge all regions that were classified as Walls to create a single Walls region).
  • Export a classified point cloud region by selecting the Point Cloud tab in the Export window and then select the appropriate exporter and region that you want to export.
 

I hope this tip comes in handy next time you are working with an indoor scan dataset!

0 comments
19 views

Permalink