[mapserver-users] Baffled by a MapServer WCS

[Ari Jolma]

Hi,

I'm trying to get the GDAL WCS client working and in the process trying 
different WCS servers.

I just found this http://nsidc.org/cgi-bin/atlas_north and I'm trying to 
use its WCS

I'm making WCS 1.0 and 1.1 GetCoverage calls on a dataset that seems to 
be natively served in EPSG:32661:

http://nsidc.org/cgi-bin/atlas_north?SERVICE=WCS&REQUEST=GetCoverage&VERSION=1.0.0&COVERAGE=sea_ice_concentration_01&FORMAT=GeoTIFF&BBOX=-3961770.085,4312961.971,-3911770.085,4362961.971&WIDTH=2&HEIGHT=2&CRS=EPSG:32661

Error: Requested BBOX 
(-5336721.37969822,2086027.77164232,-5316625.78536214,2109378.29356774) 
is outside requested coverage BBOX 
(-3961770.085,-3961769.906,3961769.894,4362961.971)

http://nsidc.org/cgi-bin/atlas_north?SERVICE=WCS&VERSION=1.1.1&REQUEST=GetCoverage&IDENTIFIER=sea_ice_concentration_01&FORMAT=image%2Ftiff&BOUNDINGBOX=-3924270.085,4350461.971,-3949270.085,4325461.971,urn:ogc:def:crs:EPSG::32661&RangeSubset=pixels&WIDTH=2&HEIGHT=2&GridBaseCRS=urn:ogc:def:crs:EPSG::32661&GridCS=urn:ogc:def:cs:OGC:0.0:Grid2dSquareCS&GridType=urn:ogc:def:method:WCS:1.1:2dGridIn2dCrs&GridOrigin=-3949270.085,4350461.971&GridOffsets=25000,25000

Requested BBOX 
(-5335202.686558,2107853.71031472,-5335202.686558,2107853.71031472) is 
outside requested coverage BBOX 
(-3961770.085,-3961769.906,3961769.894,4362961.971)

For the first one I'm making a fix on the GDAL side for the grid origin 
not being at the center of a pixel and for the second one I'm setting 
the offsets to positive values and leaving out the 0,0 in the middle. 
For the 2nd one I'm also making axis order inversion since EPSG::32661 
is N,E. That's why the GridOrigin in like it is. I'm not sure whether 
MapServer applies axis inversion in the 1.1 in this case.

Anyway, the baffling thing is that MapServer reports in both cases the 
requested BBOX (the one I'm sending, I guess) to be outside coverage 
BBOX and changed from what I sent -- there is obviously a reprojection 
done. The values are strange and I can't find/think in what CRS they are.

Any ideas?

Thanks,

Ari