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I own about 200 acres of forest with about 350' of elevation change. I have a DJI 4 Advanced and my goal is to produce elevation maps to plan the building of one or more ponds.

I've tried and failed, at researching how to do this. It appears to be fairly easy if you don't have a Mac to use the LAS file and the LAS toolkit in QGIS to perform these functions. I've tried to run the LAS tools through WINE with no success. I tried GRASS, but it's LAS toolkit also doesn't work on a Mac.

So my question is "is there a way to filter out trees (it's that time a year again when the leaves are down, so I can get shots through to the floor) with either the LAS file or the GeoTIFF on a Mac?".

If there is no easy way, I'll try again at using WINE, or as a last resort might resort to buying a Windows computer. I've been using MapsMadeEasy to process my pictures.

BBG_GIS
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Dsaw
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    There is certainly no reason you need to use Windows for point cloud processing. Have you looked at the following tutorial?: https://docs.qgis.org/2.8/en/docs/training_manual/forestry/basic_lidar.html. If you are willing to work in R, you can use the lasground() function in the lidr package: https://cran.r-project.org/web/packages/lidR/lidR.pdf. Lastools has a lasground tool: https://rapidlasso.com/lastools/lasground/. Another option is to use the PDAL ground tool: https://pdal.io/tutorial/pcl_ground/index.html – Aaron Jan 18 '19 at 03:18
  • If you are using photoscan you can classify the pointcloud. You can also check this: https://gis.stackexchange.com/questions/191034/options-for-visualizing-lidar-data-on-mac-os-x, or try pdal – Gerardo Jimenez Jan 18 '19 at 13:29
  • Check this also http://macappstore.org/pdal/ – Gerardo Jimenez Jan 18 '19 at 13:34
  • Thanks for the answers, it'll have to wait till next week for me to try some of these out and I'll report back. – Dsaw Jan 19 '19 at 02:41
  • What part of the world are you in? There may be and existing and published LiDAR dataset available. – GBG Jan 23 '19 at 20:02
  • We'll see, but between learning R vs. PDAL, PDAL appears on the surface easier to use (I think the first page I pulled up on it showed the command to look for ground points and ignore anything sticking up like trees or buildings). It's installing now, but I probably won't have time to mess with it tonight. – Dsaw Jan 24 '19 at 03:20
  • I may be wrong on PDAL, and have to learn R, but before I give up, how does one enter commands in PDAL without OSGeo4W Shell? "PDAL info" commands work from the Mac command line, but "Translate" commands only yield a "PDAL: Cannot determine reader for input file". I've tried converting LAS files to LAZ, and using the ground filter and got the same error. – Dsaw Feb 25 '19 at 02:32
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    Solved my problem, stupid syntax error. Obviously common knowledge for those in the know, but as a newbie, I saw the ^ in the examples and was including it in the commands. – Dsaw Mar 26 '19 at 01:13

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