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I've recently been tasked with cleaning up a LiDAR file of a river where I need to remove trees, shrubs and power lines that run right across the river.

I was looking into LAStools but it has a limit of 1 million points before you require a license (the file has ~4.7mil points distance ranging from 0.001 to 0.020). Its a relatively small area, but as you can imagine pretty detailed.

lasview was awesome for this job, getting the views just right and entering edit mode to remove points. Is there an alternative to lasview for this type of editing? What other kind of software are available?

I've already contacted Martin Isenburg about the possibility of purchasing a lasview license but I understand that he is a pretty busy guy and getting a reply by mail might take some time that I don't necessarily have.

Andre Silva
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Dixos
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  • Take a look at FUSION developed by the US Forest Service. http://forsys.cfr.washington.edu/fusion/fusionlatest.html – Jeffrey Evans Nov 02 '16 at 20:17
  • I checked out Fusion, but I don't exactly find any where to select points (or like lasview, create a shape) and remove extreme outlier elements such as power line poles and cables. – Dixos Nov 02 '16 at 21:58
  • So basically, you want to keep only ground points? – Andre Silva Nov 03 '16 at 11:00
  • Yes, but I need the ability to manually remove points as well, with something similar to lasview's implementation for example.Converting the file to ASCII and using a viewer to locate a point for deletion, then find point(s) in the text file and remove them that way is borderline soul destroying. – Dixos Nov 03 '16 at 14:33
  • Why does it need to be manual? Is the point cloud already classified? For example; why would not the following approach be suitable for your situation: http://gis.stackexchange.com/questions/208134/keeping-only-ground-points-class-2-with-lasground-in-qgis-2-14? – Andre Silva Nov 03 '16 at 15:19
  • Something like that would surely work, unfortunately the file I have at hand is completely unclassified. Here's the file in question so you can have a look: https://www.dropbox.com/s/1xvvnmxnukdly4e/935%20GeoRef%20-%20Original.las?dl=0 It's easy enough to lax the amount of points by removing some of the noise. – Dixos Nov 03 '16 at 18:53

2 Answers2

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You want to remove non ground points in the scene, but your LiDAR cloud is unclassified. Therefore, instead of doing this manually, use some customized tools for such tasks.

For classifying the point cloud between ground and non ground points, see:

And for keeping only the ground points, see:

Community
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Andre Silva
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  • Thanks a lot. Both links provide some very good insight in classifying points. A lot of information to process for someone just starting out learning about Lidar. – Dixos Nov 13 '16 at 20:25
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If the "manual editing in lasview" is exactly what you need but a LAStools license is out of the question then you could put in an application for a temporary "LASmoons license" that were created for exactly such situations ... (-:

LAStools
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  • Thanks a lot! I've actually contacted Martin from LAStools about purchasing a license already. I'd reply sooner but have been recovering from surgery. – Dixos Nov 13 '16 at 20:14