1

I'm new to GRASS gis and I'm trying to do a topographic correction (i.topo.corr) of 9 ASTER bands using SRTM dem. I keep getting this error message:

ERROR: Illumination model is of CELL type

Is this error referring to my elevation raster, and if so how do I change the type to the appropriate one?

1

"CELL" type means integer type (see also http://grasswiki.osgeo.org/wiki/GRASS_raster_semantics#Raster_map_precision_types). Since SRTM is delivered as integer map but i.topo.corr expects a floating point map, you need to convert/resample that map beforehand.

For resampling methods available in GRASS GIS, see the manual or Wiki, especially:

http://grasswiki.osgeo.org/wiki/Interpolation#Resampling_of_raster_maps_to_finer_resolution

since you may want to match the resolution of your DEM to that of the ASTER channels.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.