> I see some tutorials for extracting buildings, but I'm interested in traces of former land-use - finding artificial linear ground features under the foliage.
I use CloudCompare ( open source ) to good result for lidar point clouds. ( https://www.danielgm.net/cc/ ) ...See https://drive.google.com/file/d/1h9EmRFOI-WWsQgz3mq9mZ4fuMcDJFfRn/view?usp=sharing - your mileage may vary, there is a learning curve, but it is a powerful tool. That example was made from 'first' return data. If you wanted to get rid of vegetation, filtering to 'last return' can remove most of it, especially if your just tracing. The "Intensity" data does seem to make the sidewalks and pavement pop out from grass, etc. It might even be possible to distinguish asphalt vs. concrete, etc. from the signature. https://drive.google.com/file/d/1unUkJTym-V5SrZDrYA-WYInCKkdo0FrJ/view?usp=sharing All lidar is not created equal, depending on what reason they flew the mission ( resolution, flight lines, etc. ). But this is some hangers from the WA DNR King County Lidar near my house at Renton Field. Certainly sufficient for tracing: https://drive.google.com/file/d/1RmWPEQkSrSYi3uRjVn1AjeV3xLDu6Ksy/view?usp=sharing JOSM seems to have a heart attack when importing more than average size imagery (understandably ). so you may want to clip your lidar data. Or trace in a GIS program like Qgis and upload the traces to JOSM. Michael Patrick, Data Ferret <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=icon> Virus-free. www.avast.com <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=link> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
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