Q: What format should my DEM be in when using aplcorr?

APL expects the Digital Elevation Model (DEM) to be in a 1-band ENVI BIL or BSQ file format. This is a simple binary format where the data is stored as a string of binary information with an accompanying header file that describes the number of bands / lines / samples. Further information on this file format can be found in the ENVI tutorial: http://www.exelisvis.com/portals/0/tutorials/envi/ENVI_Intro.pdf

The elevation data should be projected in WGS84 Latitude and Longitude with heights referenced to the WGS84 spheroid. If possible a Digital Surface Model (DSM), providing the top of canopy / building height is preferred.

For preparing a DEM for use in APL the ARSF DEM scripts (available to download from https://github.com/pmlrsg/arsf_dem_scripts) can be used. For more details on usage see the tutorial.

You can convert an existing DEM (providing the heights are referenced to the WGS84 spheroid) using GDAL, for example:

gdalwarp -t_srs EPSG:4326 -of ENVI in_dem_utm.tif out_dem.dem

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Last modified 5 months ago Last modified on Jun 22, 2017 1:27:56 PM