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I have the following process for automatically creating building outlines/footprints from Las files and was wondering if anyone can help improve it or has suggestions for other processes to use?

EXPERIMENTS:

A. ArcGIS - Lidardataset tools : while you can see just the building class points you can not create polygon automatically. There is the minimum bounding geometry but as it looks at the dataset as a whole it requires you to manually choose the points for each building.

B. External Lidar Analysis tool by Overwatch - building extraction is a core functionality. http://www.featureanalyst.com/lidar_analyst.htm (No longer active - July 28/2014)
It took approx 8 minutes to create a bare earth (essential) and then extract the buildings. It gives the best results by far, even capturing building under the trees (1&4). This is without even looking at a tutorial as it is a very intuitive interface.

enter image description here

Some issues are it has missed the covered corridors (3) but has correctly left out the open roof (2).

C. LASTOOLS - used lasmerge to merge 4 relevant tiles and then lasclip to extract zone of AOI only.

arcpy.lasboundary("AOI.las","1","buildings","true","true","shp","AOI_buildings.shp","","#","true")  

enter image description here

The output was very jagged so I used:

arcpy.SimplifyBuilding_cartography("AOI","AOI_buildings_simplified.shp","4 Meters","0 SquareMeters","NO_CHECK")

enter image description here

and then ran:

arcpy.SimplifyPolygon_cartography("AOI_buildings_simplified","AOI_s.shp","POINT_REMOVE","1 Meters","0 SquareMeters","NO_CHECK","KEEP_COLLAPSED_POINTS")

enter image description here

1 and 2 show the issue areas. Part of it is due to bad lidar classification.

This gives good building lines for long straight edged buildings but if there is overlap by branches or it is a complex building with multiple edges, roofs on multiple levels close to each other etc, manual creation is necersary for any detailed site level work. For general estimation roof shape the process is accurate enough. Process takes less than 10mins total once the process has been finalized.

My Research: https://stackoverflow.com/questions/5037588/simplified-or-smooth-polygons-that-contain-the-original-detailed-polygon and the process suggested by @gromix and What are Definition, Algorithms and Practical Solutions for Concave Hull?

  • Could you fix the link in section B? Or is that company still around? – ianbroad Jul 9 '14 at 22:53
  • Sorry it doesn't seem to be around any longer. I will be looking at a few more options in the next few weeks so stay tuned... – GeorgeC Jul 27 '14 at 23:08
  • The Lidar Analyst extension for ArcGIS is still available, the web page is at: textronsystems.com/products/geospatial/lidar_analyst – user53100 Jun 2 '15 at 19:59
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I have developed a tool named Clean Extracted Building Using Regularize Building Footprint Tool which wraps around of ArcGIS Regularize Building Footprint tool and improves the outcome of extracted building footprints.

More details about the Clean... tool can be found in my blog.

  • For cleaning up building footprints from lidar, please check out the ArcGIS Regularize Building Footprint Tool. Another new tool in ArcGIS Pro 1.3 is the Classify LAS Building. – Arthur Crawford Jul 19 '16 at 16:46
  • Can you elaborate the answer, explaining how these tools work? – Andre Silva Jul 19 '16 at 17:56
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    Hello Arthur, welcome to GIS Stack Exchange. It seems nice this tool you are developing. I tried to improve a little bit the readability of your answer. You can roll the edit back if you prefer the previous version. Always try to make posts here the most self-contained as possible, so if you could provide a more detailed explanation within this post what the tool does and how it is different from ArcGIS's, it would be nice. See for example, Thad's answer, the link he provided is dead, and now his answer does not make much sense. – Andre Silva Jan 8 '17 at 18:33
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    Also, it seems you have another account here in GIS SE (because there is another related answer from Arthur Crawford). You should probably merge the accounts. See how it can be done here. Thanks. – Andre Silva Jan 8 '17 at 18:37
  • I have given it in detailed way with couple of steps only - spearminds.com/… – Rakesh Giri Aug 21 '18 at 5:25

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