Jon Morris
2021-05-28 13:56:56 UTC
Hello all,
One of our users reported a difference in outputs after we upgraded from GDAL 2.2 to 3.2. Our tool is using gdal_translate to resample a raster from 5m to 10m and the outputs are very different.
I'm ok with things changing between major versions, but when investigating, I found that the outputs also change depending on whether the input file has overviews. I was aware of the issue with gdalwarp where overviews are used as a shortcut (http://erouault.blogspot.com/2014/10/warping-overviews-and-warped-overviews.html), but haven't been able to find anything similar in the docs or the code when it comes to gdal_translate.
Should overviews make a difference? Is there any way to disable this behaviour, so the resampling is always done using the input raster and not the overviews?
Thanks,
Jon
Jon Morris
Software Developer
e: ***@jbarisk.com
t: +44 (0)1756 799919
www.jbarisk.com
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One of our users reported a difference in outputs after we upgraded from GDAL 2.2 to 3.2. Our tool is using gdal_translate to resample a raster from 5m to 10m and the outputs are very different.
I'm ok with things changing between major versions, but when investigating, I found that the outputs also change depending on whether the input file has overviews. I was aware of the issue with gdalwarp where overviews are used as a shortcut (http://erouault.blogspot.com/2014/10/warping-overviews-and-warped-overviews.html), but haven't been able to find anything similar in the docs or the code when it comes to gdal_translate.
Should overviews make a difference? Is there any way to disable this behaviour, so the resampling is always done using the input raster and not the overviews?
Thanks,
Jon
Jon Morris
Software Developer
e: ***@jbarisk.com
t: +44 (0)1756 799919
www.jbarisk.com
All JBA Risk Management's email messages contain confidential information and are intended only for the individual(s) named. If you are not the named addressee you should not disseminate, distribute or copy this e-mail.
Please notify the sender immediately by email if you have received this email by mistake and delete this email from your system.
JBA Risk Management Limited is registered in England, company number 07732946, 1 Broughton Park, Old Lane North, Broughton, Skipton, North Yorkshire, BD23 3FD, England.