[Qgis-user] recompiling gdal: problems with QGIS?

[Micha Silver]

Agustin Lobo wrote:

>
>
> For the future, if the user is installing a QGIS binary (i.e., ubuntu
> using Synaptic), is there any way to tell QGIS to use the gdal version
> included in FWTools? And/or would just copying the appropriate gdal*
> programs from the fwtools bin_safe directory to the /usr/bin directory 
> work?
>
The need for a gdal which includes copyright encumbered formats pops up 
on the various mail lists every few months, if my memory servers. Today, 
preparing the whole qgis tool chain is not trivial - and that's really 
the only way to get the gdal options you want. IIUC, you *can not* just 
copy binaries, *.dll's or *.so libs from fwtools into the qgis path.
Perhaps the "cleanest" solution would be to ask the package maintainers 
to supply a "gdal-good", "gdal-bad" and "gdal-ugly" in the same fashion 
that non-free audio codecs are available in binary packages. This way 
the QGIS project and  distros could stick with the FOSS only policy, but 
a private user could choose to download from some 3rd party repository 
an expanded package with the additional libraries he needs- just like 
fwtools, but merged into qgis.
I realize that I'm asking already overworked package maintainers to take 
on a whole new line of production, but it  would definitely be a boost 
to the popularity of QGIS to be able to grab a windows or ubuntu binary 
with ecw support built-in. The QGIS people themselves cannot do this 
since the licensing of ecw is too restrictive regarding redistribution 
and changes - even tho' the source code is available - and won't fit in 
with GPL. (Somehow, gvSIG managed to sidestep this issue?). So the only 
way around for users who want a working GIS software stack, without the 
chore of recompiling everything is to depend on a friendly neighborhood 
package maintainer who is willing to compile gdal against the ECW libs.
 
Regards,
Micha
> Thanks
>
> Agus
>
> Craig Leat wrote:
>> Hi Agustin
>>
>> Agustin wrote:
>>> Therefore, I understand I should not try to make the current QGIS I 
>>> have
>>> work with a new compiled gdal.
>>
>> Yes. gdal is a dependency, so if you change it you need to recompile
>> everything that depends on it.
>>
>>> BUt could I have a second version of gdal
>>> which I would use for converting ECW and MrSid files to formats that
>>> QGIS can accept?
>>
>> Yes you can have multiple versions of gdal, just head my earlier
>> warning if you ever decide to build qgis. You could try the FWTools
>> [1] binary as this offers the formats [2] you need.
>>
>> Craig
>>
>> [1] http://fwtools.maptools.org/
>> [2] $ ./gdalinfo --version
>> GDAL 1.5dev, FWTools 2.0.0, released 2007/11/12
>> $ ./gdalinfo --formats | grep -i "ecw"
>>   ECW (rw): ERMapper Compressed Wavelets
>>   JP2ECW (rw+): ERMapper JPEG2000
>> $ ./gdalinfo --formats | grep -i "mrsid"
>>   MrSID (ro): Multi-resolution Seamless Image Database (MrSID)
>>
>