Find Duplicate Lidar Points

The Find Duplicate Lidar tool finds lidar points with the same XYZ location. It can also consider additional attributes to further refine what is considered a duplicate.

This tool requires Global Mapper Pro

Use the Lidar Toolbar button , or right-click on the layer in the Control Center and go to Layer> DUPLICATES - Delete Duplicate Lidar Points.

The Select Lidar Fields dialog provides options to include additional attribute to consider a point a duplicate. If no attributes are checked, any points that contain the same XYZ will be considered duplicates.

Check additional attributes to require a more strict check of duplicates. Points must have the same XYZ, and share the same values for the selected attributed to be considered duplicates.

• CLASS - Points will only be considered duplicate if they have the same classification code.
• GPS_TIME - Compare the timestamp when checking for duplicates.
• INTENSITY - Compare the intensity when identifying duplicate points.
• RETURN_NUM - Points in the same location must also have the same return number to be considered duplicates.
• RETURN_CNT - Point must also have the same number of returns to be considered duplicates.
• SOURCE_ID - Points must have the same point source ID to be considered duplicates. (This is usually the flight pass or other collection instance).

When the search is completed, a dialog will appear indicating how many duplicate points were found. Press OK to confirm marking the duplicate points as deleted. This will exclude them from export and other analysis, and hide them from view, but will not remove them from the original file.

Delete All Copies of Duplicate Points - When this box is unchecked, one point from each set of duplicates will be kept, and so there will still be one point in that location. If this box is checked, all points that are duplicates will be marked as deleted.

See also Deleting and Undeleting Features.