Hi all! Does anyone have any experience with bringing in 2GB+ orthomosaic maps into QGIS? I do not have tiles, just the mass site. Thanks!
Well, that’s close to 2gb… From earlier this week. I might have bigger ones around here. Did you need it specifically over the 2gb? You can build pyramids to speed things up. This makes it smooth.
The file I am on right now is 2.7GB. I will give this a try and report back. Thanks @Brent_W!
First pass crashed QGIS and corrupted the file. Luckily I made a copy per the softwares recommendation. I think part of the problem is that even though the image is only 82K pixel wide the resolution is 0.4in/px so it is very dense thus it gave me options in the Pyramid menu for 40k and 20k. I went down to 5k and it appears to have worked, but still takes at least 3 minutes to render with each zoom action.
I can create pyramids at multiple levels correct?
yes you can create pyramids at multiple levels.
It shouldn’t even be close to the limit for size I don’t think…
Also,which version of QGIS are you using?
Not to be rude but did it freeze and you got tired of waiting…?
or did it actually crash…
Man, am I glad you backed it up first!
Not on the absolute latest version, but one back. It actually crashed and gave me the error report notification.
holding image datasets in large mosaics sucks in my opinion
also holding them very small tile caches also sucks
i like to chop everything into tiles that are in the 1 to 100 megabyte range per tile
then i access them in qgis and arcgis through a .vrt file
https://gdal.org/drivers/raster/vrt.html
the result is that i can access multi gig image sets even on a old toughbook u1 with QGIS
I can download the 4k tiles, but the end goal of this task is to provide a PDF of the map with some overlays so tiling is actually a step backwards. I have seen many posts of GIS pros using 10-20GB orthos and just cannot figure out how. I got the second attempt to work after doing 10k, 5k and 2k pyramids, but even that process took 45 minutes.
Thanks @Brent_W for the solution! It took 90 minutes, but I was able to build 3 levels of pyramids and it works very well now.
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