[mapserver-users] Disregard ECW header for TFW in TILEINDEX ?

[Frank Warmerdam]

Lars I. Nielsen (GisPro) wrote:
> Hi,
> 
> I'm trying to set up Mapserver as a WMS server, serving multiple 
> seamless coverages consisting of ECW raster tiles.
> 
> My problem is, that the ECW files have been delivered with faulty header 
> information, and there's too many to fix manually, and the error cannot 
> easily be remedied programmatically.
> 
> However, I have generated TFW files for each tile that are correct, but 
> how do I force Mapserver to use the TFW files and disregard the faulty 
> ECW header ?

Lars,

As it happens this is not a unique situation and MapServer itself has some
logic to address it.  If you add:

   PROCESSING "EXTENT_PRIORITY=WORLD"

to your layer definition, then world files will be searched for in preference
to using the georeferencing returned by GDAL.   I'm not sure exactly when this
was incorporated but I imagine it is in 5.4 and later.  Also the file extension
should likely be either .eww or .wld, not .tfw for ecw files.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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