[Qgis-developer] Loading large raster files (vrt) is slow

[Ziegler Stefan]

Hi

I have a VRT with approx. 8000 raster files (each 2000 x 2000 pixel). The very first loading into QGIS takes "rather long" (perhaps 1 minute) on a fast machine (SSD, 3.4 GHz). Saving the project file and reopening again is fast. In debug mode I saw that some statistics/histogram is calculated the first time. 

But the main problem is when trying to access the layer properties. Even with a calculated histogram opening the layer properties dialog takes 1 minute again.

Did I miss some magic settings/options? Or does QGIS really needs to calculate some statistics on the first load and on opening the layer properties dialog every time?

I'm on master and Ubuntu 14.04 64 bit. "Create raster icon" is NOT checked :-)

Best regards
Stefan


Freundliche Grüsse 
Stefan Ziegler 
Kantonsgeometer 

Amt für Geoinformation
Amtliche Vermessung 
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Telefon +41 32 627 75 96
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stefan.ziegler at bd.so.ch
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