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Is there any procedure to automatically correct lidar classification? My LAS Dataset has water listed as ground and buildings listed as vegetation.

Just wondering if there is any option to fix this.

  • Attempting to change your classification codes is a bit risky. It sounds like the vendor, or subsequent processing, scrambled the classification codes. These errors may not be systematic. Do check your version in the LAS header. There were some changes to classification codes from old versions. You may want to start from scratch or contact the vendor to find out where things may have gone sideways. – Jeffrey Evans May 12 '14 at 22:08
  • Appreciate the response – rspencer38 May 13 '14 at 11:00
  • Not everybody uses the standard, and even then numbers after 12 are open for anybody to use. There is a strong chance if 1 file is classified in a different way to the ASPRS spec then they are all classified that way from that supplier. If you can predict or understand the supplied class codes then translating to ASPRS class standard codes could be done in a model or python script. If it is unreliable what class codes you are likely to get complain bitterly to your supervisor, your supplier and demand they keep it consistent even if it consistently non-compliant. – Michael Stimson May 13 '14 at 21:47
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Are you sure that your data is ASPRS compliant? It doesn't sound like it is. Codes are listed in the spec (page 8) and also here, this is an older version but the latest is a little difficult to find. The class codes haven't changed since 1.1.

Apparently you can edit a class codes (see here and here - the latter link lists the ASPRS class codes).

The tool is Change LAS Class Codes (3D Analyst). This will blanket change codes from X to Y, so in your case water (9) to ground (2).

Be careful of the order of change: if you change 9 (water) to 2 (ground) and then 2 (ground) to 6 (buildings) then all of your ground is now building. You will need to find an empty class to go first so that you don't double up.

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