[Qgis-developer] Data for QGIS Hackfest

[Tim Sutton]

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Maciej Sieczka wrote:
> Andreas Neumann pisze:
>
>> I'd like the mention that the display of very large rasters is
>> normally not a problem if you used gdaladdo to add pyramids to your
>> data. You can use rasters with the hundreds of gigs of filesize
>> without a bottleneck. You'd have to build the pyramids however. If
>> you store your data in multiple files instead of just one, you should
>> build a tileindex with gdaltindex. See
>> http://www.gdal.org/gdal_utilities.html for more infos.

QGIS doesnt (that I know of) work with tile indexes but you can create a
gdal .vrt virtual dataset from a bunch of files (using gdalbuildvrt.py).
You can also build pyramids on the virtual dataset and I have found
performance to be reasonable once zoomed in a little on a ~1TB test dataset.

Regards

Tim Sutton - QGIS Project Steering Committee Member (Release  Manager)
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