PNG24 output and GDAL dependency?

[Frank Warmerdam]

Eijnden, B. van den (Bart) wrote:
> Hi list,
> 
> we are trying to create a minimal PHP/Mapscript rpm, but are running into
> the issue that for 24 bits PNG output there is a dependency on GDAL. Why is
> this and can it be avoided somehow?
> 
> Also, if we try to use 8 bit PNG (PC256 instead of RGB/RGBA), we get a
> segfault in PHP/Mapscript if GDAL is not compiled in. If GDAL is compiled
> in, all works fine.

Bart,

I am not aware of any reason why either would be the case.  PNG24 output
should work fine without GDAL.  Likewise I don't know why you run into the
problem with PC256.   It is *possible* that with GDAL linked in an internal
copy of libpng is getting used instead of the system libpng, though I would
advise against using internal libpng in an RPM setup.

I would suggest trying to debug each of these problems to try and work out
what is happening.

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