Only save ground in heatmap tif

las_outputs.py

@@ -231,8 +231,8 @@ def main():
         # Make a raster from point cloud
         print('Creating heat map raster...')
         tif_name = os.path.join(output_tif_dir, las_basename + '.tif')
-        call_lastools('blast2dem', input=las_data, output=tif_name,
-                      args=['-step', 0.2], verbose=False)
+        call_lastools('las2dem', input=las_data, output=tif_name,
+                      args=['-step', 0.2, '-keep_class', 2], verbose=False)
 
         # Extract elevations along profiles from triangulated surface
         print('Extracting profile elevations...')