[gdal-dev] problems serving DTED data via WCS

[Jim Hammack]

I am trying to serve DTED data in its native format using WCS with 
mapserver 6.0.0 on Slackware 13.1.   If I serve the data as a 16-bit 
GeoTIFF or do a WCS 2.0.0 GetCoverage with a PNG output, the images look 
good.  But when I serve the same data using the GDAL/DTED driver the 
.dt1 file contains only 0 values for the data when using GetCoverage.  
Interestingly, shp2img gives me a file with nothing but 21074 (0x5252) 
for the data values.  In both cases the output of gdalinfo looks okay.

So it seems like mapserver is finding the data okay, but gdal (1.8.0) is 
not writing the dt1 file properly.

Am I missing something in the WCS configuration or is gdal confused?

                                                                 Thanks,
                                                                     Jim


------------------------
# this works
OUTPUTFORMAT
   NAME "GEOTIFFINT16"
   DRIVER "GDAL/GTiff"
   MIMETYPE "image/tiff"
   IMAGEMODE "INT16"
   EXTENSION "tif"
END

shp2img -m dted1.map -i PNG -l "elevation" -o fred.dt1 -e -90.0 30.0 
-89.0 31.0  # works

http://localhost/cgi-bin/mapserv?map=/mapserver/dted1.map&SERVICE=WCS&VERSION=2.0.0&REQUEST=GetCoverage&coverageid=elevation&format=png&subset=lon_axis,http://www.opengis.net/def/crs/EPSG/0/4326(-90.0,-89.0)&subset=lat_axis,http://www.opengis.net/def/crs/EPSG/0/4326(30.0,31.0)

---------------------------
# this does not
OUTPUTFORMAT
     NAME "DTED"
     DRIVER "GDAL/DTED"
    IMAGEMODE "INT16"
     EXTENSION "dt1"
END

shp2img -m dted1.map -i DTED -l "elevation" -o fred.dt1 -e -90.0 30.0 
-89.0 31.0  # contains 0x5252 values only

http://localhost/cgi-bin/mapserv?map=/mapserver/dted1.map&SERVICE=WCS&VERSION=2.0.0&REQUEST=GetCoverage&coverageid=elevation&format=DTED&subset=lon_axis,http://www.opengis.net/def/crs/EPSG/0/4326(-90.0,-89.0)&subset=lat_axis,http://www.opengis.net/def/crs/EPSG/0/4326(30.0,31.0)  
# contains zero values only

---------------------------

mojo:/mapserver> gdalinfo fred.dt1
Driver: DTED/DTED Elevation Raster
Files: fred.dt1
        fred.dt1.aux.xml
Size is 1201, 1201
Coordinate System is:
GEOGCS["WGS 84",
     DATUM["WGS_1984",
         SPHEROID["WGS 84",6378137,298.257223563]],
     PRIMEM["Greenwich",0],
     UNIT["degree",0.0174532925199433],
     AUTHORITY["EPSG","4326"]]
Origin = (-90.000416666666666,31.000416666666666)
Pixel Size = (0.000833333333333,-0.000833333333333)
Metadata:
   DTED_VerticalAccuracy_UHL=NA
   DTED_VerticalAccuracy_ACC=NA
   DTED_SecurityCode_UHL=U
   DTED_SecurityCode_DSI=U
   DTED_UniqueRef_UHL=
   DTED_UniqueRef_DSI=000000000000000
   DTED_DataEdition=01
   DTED_MatchMergeVersion=A
   DTED_MaintenanceDate=0000
   DTED_MatchMergeDate=0000
   DTED_MaintenanceDescription=0000
   DTED_Producer=
   DTED_VerticalDatum=MSL
   DTED_HorizontalDatum=WGS84
   DTED_DigitizingSystem=
   DTED_CompilationDate=
   DTED_HorizontalAccuracy=NA
   DTED_RelHorizontalAccuracy=NA
   DTED_RelVerticalAccuracy=NA
   DTED_OriginLatitude=0300000N
   DTED_OriginLongitude=0900000W
   DTED_NimaDesignator=DTED1
   AREA_OR_POINT=Point
   TIFFTAG_XRESOLUTION=72.000000
   TIFFTAG_YRESOLUTION=72.000000
   TIFFTAG_RESOLUTIONUNIT=2
Corner Coordinates:
Upper Left  ( -90.0004167,  31.0004167) ( 90d 0' 1.50"W, 31d 0' 1.50"N)
Lower Left  ( -90.0004167,  29.9995833) ( 90d 0' 1.50"W, 29d59'58.50"N)
Upper Right ( -88.9995833,  31.0004167) ( 88d59'58.50"W, 31d 0' 1.50"N)
Lower Right ( -88.9995833,  29.9995833) ( 88d59'58.50"W, 29d59'58.50"N)
Center      ( -89.5000000,  30.5000000) ( 89d30' 0.00"W, 30d30' 0.00"N)
Band 1 Block=1x1201 Type=Int16, ColorInterp=Undefined
   NoData Value=-32767
   Unit Type: m