[mapserver-users] serving sparse DTED with WCS

[Even Rouault]

On mercredi 4 avril 2018 19:51:56 CEST Burkhardt, Glenn B        UTAS wrote:
> DTED data is notoriously sparse.  If one combines all the files in a DTED
> dataset into a single Geotiff file using something like " gdalwarp -co
> TILED=YES */*.dt2 dted2.tif"
> 
> But GDAL will build a bounding box that's square with the world, and there
> might not be data for every 1x1 deg section of the bounding box.
> 
> When this happens, Mapserver fills in the missing data with zeros. 
> Additionally, there might be data missing from within a 1x1 deg DTED file,
> and it is marked with a  NODATA flag of -32767.
> 
> Is there some way for Mapserver to communicate to a client where data is
> missing?  I can't find anything in the coverage information provided to a
> WCS 1.0.0 client.

Glenn,

You can define in the LAYER.METADATA section things like for WCS 1.0 and WCS 
1.1

"wcs_rangeset_nullvalue" "-32767"

Actually I see this wasn't documented. I've just added it in
http://mapserver.org/ogc/wcs_server.html

For WCS 2, use "wcs_nilvalues"

Even

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