[Qgis-user] Re: qgis and big raster catalogs

[Andrea Peri]

>One question: how to get a fast raster catalog in QGIS with a big number of rasters in it? (in this case 400 ecw)
>
>I am having trouble getting this to work... I tried a vrt catalog and qgis just hangs when I load it.
>
>Reducing the number of images makes it ok.
>
>Is this a know limitation of gdal/qgis? Is there another approach to catalogs (not mosaics)?


Hi to have a good working catalog VRT for qgis, you should do a prelimiary
operation.
Infact the gdal catalogs has not the statistics, and wgis try to calculate
it the stats, causing the slooowing when the raster are big.
To avoid this you can find how to do here.

http://trac.osgeo.org/gdal/wiki/CatalogueForQIS


Regards,

-- 
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Andrea Peri
. . . . . . . . .
qwerty àèìòù
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