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I have a big geotiff file (resolution 2m, 192500 columns, 120000 rows, 100GB) representing a DEM model for a whole country. When I open in in ArcGIS it works fine, but in QGIS I need to wait half an hour for the file to load and show me the result. This make it impossible to perform any operations on the raster.

What can I do to make it work in QGIS? Why does this problem occur?

Edit: adding raster Info

enter image description here

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    Please show gdalinfo report of the DEM file. Important part is if GeoTIFF is written as tiled and if it has overviews. – user30184 Feb 13 '17 at 10:25
  • no problem, but how and from where can I get it? – sweet.sugar.cola Feb 13 '17 at 11:06
  • Through command line gdal.org/gdalinfo.html or from menu Raster-Miscellaneous-Information. – user30184 Feb 13 '17 at 11:36
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Your image has no overviews/pyramids. You can use GDAL to generate them:

gdaladdo -ro --config COMPRESS_OVERVIEW DEFLATE --config PREDICTOR_OVERVIEW 2 swissALTI3D_LV03LN021.tif 2 4 8 16 32 64 128 256
  • Probably ought to note that this will increase storage ~33% – Vince Feb 13 '17 at 16:33
  • As the original is not compressed, the overviews will probably be really really tiny. – bugmenot123 Feb 13 '17 at 16:40
  • I read about the pyramids but the problem is that the file is already big and there is a problem with finding a place to store it. Would it help somehow to compress it? – sweet.sugar.cola Feb 14 '17 at 9:04
  • You can try gdal_translate -co NUM_THREADS=ALL_CPUS -co COMPRESS=DEFLATE -co PREDICTOR=2 -co TILED=YES swissALTI3D_LV03LN021.tif swissALTI3D_LV03LN021_deflate.tif which will easily reduce to the size by 10. – bugmenot123 Feb 14 '17 at 10:40

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