[Qgis-developer] Re: [Qgis-user] Building image pyramids -> qgis crashing

[Frank Warmerdam]

Oleg Gusev wrote:
> Am Sonntag 13 April 2008 20:53:11 schrieb Maciej Sieczka:
>> Here Frank talks about gdalwarp and "-co COMPRESS" interaction issues,
>> leading to compression under-performance. How does it relate to QGIS
>> crashing when GDAL function for creating overviews is called, as
>> described in Trac [1]?
>>
> "under-performance" is a real under-statement here. gdalwarp (and 
> gdaladdo) often segfault when used with "-co COMPRESS" option.
> Both programs use libtiff to write compressed data into an existing
> tiff file, so they fail at the same place.

Oleg,

I am interested in bug reports on GDAL 1.5.1 with libtiff 3.9 CVS head
or libtiff 4 CVS head crashing when creating compressed overviews.

There are known to be problems with older versions, but I believe the current
release GDAL using the internal libtiff (or the cvs head of the 3.9 or 4
branches) run error free.

If you can't assure that a sufficiently recent libtiff will be used, I
would strongly advise against building compressed overviews.  In fact,
I'm generally not super keen on them.

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