Using GDAL WMS Driver

[Chris Helm]

Hi All,

I'm searching for any use cases of using the new GDAL WMS driver within
MapServer. The goal is to use the GDAL WMS .xml file (below) as the raster
image in a mapserver layer definition (also below). I can use the xml file
successfully within QGIS 9.0 and also convert it into other formats on the
command line via gdal_translate. I've re-compiled MapServer to read the new
GDAL install and am getting a "format not recognized" error (below) from
MapServer.

MapServer Layer Def:
LAYER
  NAME "gdal_wms_test"
  STATUS OFF
  TYPE RASTER
  DATA "/local/path/to/gdal_wms.xml"
  PROJECTION
   "init=epsg:4326"
  END
END

GDAL XML File:
<GDAL_WMS>
    <Service name="WMS">
        <Version>1.0.0</Version>
        <ServerUrl>http://localhost/cgi-bin/wms_server?</ServerUrl>
        <SRS>EPSG:4326</SRS>
        <ImageFormat>image/png</ImageFormat>
        <Layers>wms_test_layer</Layers>
        <Styles></Styles>
    </Service>
    <DataWindow>
        <UpperLeftX>-105.003889</UpperLeftX>
        <UpperLeftY>40.412778</UpperLeftY>
        <LowerRightX>-104.98333</LowerRightX>
        <LowerRightY>40.399722</LowerRightY>
        <SizeX>580</SizeX>
        <SizeY>480</SizeY>
    </DataWindow>
    <Projection>EPSG:4326</Projection>
    <BandsCount>3</BandsCount>
</GDAL_WMS>

Here's the output of gdalinfo on the above xml file:

>>$ gdalinfo gdal_wms.xml

Driver: WMS/OGC Web Map Service
Files: gdal_wms.xml
Size is 580, 480
Coordinate System is:
GEOGCS["WGS 84",
    DATUM["WGS_1984",
        SPHEROID["WGS 84",6378137,298.257223563,
            AUTHORITY["EPSG","7030"]],
        AUTHORITY["EPSG","6326"]],
    PRIMEM["Greenwich",0,
        AUTHORITY["EPSG","8901"]],
    UNIT["degree",0.01745329251994328,
        AUTHORITY["EPSG","9122"]],
    AUTHORITY["EPSG","4326"]]
Origin = (-105.003889000000001,40.412778000000003)
Pixel Size = (0.000035446551724,-0.000027200000000)
Corner Coordinates:
Upper Left  (-105.0038890,  40.4127780) (105d 0'14.00"W, 40d24'46.00"N)
Lower Left  (-105.0038890,  40.3997220) (105d 0'14.00"W, 40d23'59.00"N)
Upper Right (-104.9833300,  40.4127780) (104d58'59.99"W, 40d24'46.00"N)
Lower Right (-104.9833300,  40.3997220) (104d58'59.99"W, 40d23'59.00"N)
Center      (-104.9936095,  40.4062500) (104d59'36.99"W, 40d24'22.50"N)
Band 1 Block=1024x1024 Type=Byte, ColorInterp=Undefined
Band 2 Block=1024x1024 Type=Byte, ColorInterp=Undefined
Band 3 Block=1024x1024 Type=Byte, ColorInterp=Undefined

The MapServer Error:
msDrawMap(): Image handling error. Failed to draw layer named 'gdal_wms_test'. 
msDrawRaster(): Image handling error. Unrecognized or unsupported image format 
drawEPP(): Image handling error. EPPL7 support is not available. 


Any help is appreciated, thank you.

Chris