[mapserver-users] Two questions about WMS and outputformats

[Frank Warmerdam]

Rahkonen Jukka wrote:
> Hi,
> 
> By default, without having any OUTPUTFORMAT sections in the mapfile,
> Mapserver is advertising following imageformats in WMS GetCapabilities
> document:
> 
>  <GetMap>
>       <Format>image/gif</Format>
>       <Format>image/png</Format>
>       <Format>image/png; mode=24bit</Format>
>       <Format>image/jpeg</Format>
>       <Format>image/vnd.wap.wbmp</Format>
>       <Format>image/tiff</Format>
>       <Format>image/svg+xml</Format> 
> 
> Some users have been confused because WMS client builds menu items
> according to that list, but at least "image/png; mode 24bit" and
> "image/tiff" do not give any output. What is the reason to include these
> formats in getCapabilities by default, if they do not work without
> creating OUTPUTFORMATs in the mapfile first?

Jukka,

I don't know why image/tiff and image/png; mode=24bit would not work.
Perhaps you could file a ticket with minimal details to reproduce this
problem.  Please include the mapserv -v string in the ticket so I can
try to reproduce a similar scenario.  Assign the ticket directly to me.

> Second question is about JPEG outputformat. It works through GD with
> these settings
>  OUTPUTFORMAT
>       NAME "jpeg"
>       MIMETYPE "image/jpeg"
>       DRIVER "GD/JPEG"
>       EXTENSION "jpg"
>       IMAGEMODE RGB
>  END
> 
> If I change driver to "GDAL/JPEG" I get this error on ms errorlog
> [Mon Mar 16 11:16:05 2009].825000 msSaveImageGDAL(): General error
> message. Failed to create output JPEG file.
> JPEG driver doesn't support 4 bands.  Must be 1 (grey) or 3 (RGB) bands.
> 
> What makes GDAL/JPEG driver to believe that I want 4 bands? Or is it
> just best to use DG/JPEG always?

I'm surprised.  This should not occur with IMAGEMODE RGB.  I would
appreciate your also filing a ticket on this issue and assigning it to
me.

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