Can MS4W be used to serve .bil elevation data?

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Can MS4W be used to serve .bil elevation data?

James_in_Utah
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Hi,
I'm trying to serve elevation data (GMTED2010) geotiffs.  My application is expecting Int16, LittleEndian.  On the receiving end, the files I get appear to have the high order word stripped.  My elevations appear to range only from 0 to 256 meters.  I've tried several output format statements in map file, with no luck.  Then I noticed that when I type mapserv -v, bil isn't listed as one of the output formats.  Is this the case?
Any way to get this to work?
Thanks,
James
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Re: Can MS4W be used to serve .bil elevation data?

jmckenna
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Probably the easiest way to learn what formats are compiled into your
local MS4W instance, is to load this in your Web browser:
127.0.0.1/README_INSTALL.html Pan the page down and you will see
sections named "OGR Formats Supported" and "GDAL Formats Supported".
For the bil format, look for the "EHdr" driver.

You can also execute at the commandline 'ogrinfo --formats' or 'gdalinfo --formats'

-jeff

--
Jeff McKenna
MapServer Consulting and Training Services
http://www.gatewaygeomatics.com/ 

James_in_Utah wrote
Hi,
I'm trying to serve elevation data (GMTED2010) geotiffs.  My application is expecting Int16, LittleEndian.  On the receiving end, the files I get appear to have the high order word stripped.  My elevations appear to range only from 0 to 256 meters.  I've tried several output format statements in map file, with no luck.  Then I noticed that when I type mapserv -v, bil isn't listed as one of the output formats.  Is this the case?
Any way to get this to work?
Thanks,
James
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Re: Can MS4W be used to serve .bil elevation data?

James_in_Utah
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Hi Jeff,
This seems to be a gdal issue.  I do see the EHdr driver listed, so it should be able to serve Int16 .bil files.  

Below is what gdalinfo says about one of the tifs.    
Driver: GTiff/GeoTIFF
Files: 30n120w_20101117_gmted_dsc300.tif
Size is 3600, 2400
Coordinate System is:
GEOGCS["WGS 84",
    DATUM["WGS_1984",
        SPHEROID["WGS 84",6378137,298.257223563,
            AUTHORITY["EPSG","7030"]],
        AUTHORITY["EPSG","6326"]],
    PRIMEM["Greenwich",0],
    UNIT["degree",0.0174532925199433],
    AUTHORITY["EPSG","4326"]]
Origin = (-120.000138888888880,49.999861111111109)
Pixel Size = (0.008333333333333,-0.008333333333333)
Metadata:
  AREA_OR_POINT=Area
Image Structure Metadata:
  INTERLEAVE=BAND
Corner Coordinates:
Upper Left  (-120.0001389,  49.9998611) (120d 0' 0.50"W, 49d59'59.50"N)
Lower Left  (-120.0001389,  29.9998611) (120d 0' 0.50"W, 29d59'59.50"N)
Upper Right ( -90.0001389,  49.9998611) ( 90d 0' 0.50"W, 49d59'59.50"N)
Lower Right ( -90.0001389,  29.9998611) ( 90d 0' 0.50"W, 29d59'59.50"N)
Center      (-105.0001389,  39.9998611) (105d 0' 0.50"W, 39d59'59.50"N)
Band 1 Block=3600x1 Type=Int16, ColorInterp=Gray
  NoData Value=-32768


Here's a screen shot of what the hex looks like on the client end.  You can see all of the high bytes are zero:
Hex Dump

Any recommendations on where to seek further info on this?
Thanks,
James