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I have some stone wall features that I need to determine the height of in ArcGIS Desktop. I have extracted the features out of the DEM by using the extract by mask tool. Now I need a method for interpolating the surface where the features were removed so that the surface reflects bare earth with the features removed.

DEM with stone features extracted

I tried to convert the clipped raster to points and then back to a raster using IDW interpolation but the process took a lot of time and ultimately failed.

Is there an easier method for doing this or am I maybe running into some issues with my approach?

Basically, I need to find the height of these stone walls by creating a bare earth DEM without them in it. I've tried to create a DTM from LiDAR data but the stone walls weren't completely removed. So after digitising them with polygons, I've been able to extract them out of the DEM and need to interpolate the surface to effectively create a DTM without the walls in so that I can accurately calculate their height.

PolyGeo
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TJ Nagel
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    Simplest method is probably a FocalStatistics (mean) expression in the raster calculator (something like Con(IsNull(DEM), FocalStatistics(DEM, NbrCircle(3, "CELL"), "MEAN"), DEM)) or convert your DEM to points, only in a restricted area around the wall (i.e. a buffer), interpolate that with IDW, then patch that back in with something like Con(IsNull(DEM), IDW_OUTPUT, DEM) – user2856 Dec 10 '19 at 03:11
  • Okay, so constrain the DEM within the buffer before converting it to points and running IDW. That's an excellent idea. I also had someone suggest I resample the DEM to a lower resolution, run IDW and then convert it back. Thanks a lot. – TJ Nagel Dec 10 '19 at 06:32
  • If you have LiDAR data available, create a bare-earth DEM. Probably you did not make it right the first time. Take a look at https://gis.stackexchange.com/questions/101786/determining-bare-earth-dem-from-unclassified-las-file/108342#108342 and https://gis.stackexchange.com/questions/13618/converting-lidar-data-to-raster-dem-dsm-for-arcgis-input/56710#56710. – Andre Silva Dec 10 '19 at 19:51

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