[gdal-dev] Overview Pixils don't line up.

[Roarke Gaskill]

Hi,

I am seeing an issue where after I create an overview the pixels at the
lower zoom_level are slightly shifted as compared to if I don't create an
overview.

You can reproduce by running the following and comparing overview1.tif with
overview2.tif.  They don't quite line up.  You will find overview1.tif and
overview3.tif do line up.

https://eoimages.gsfc.nasa.gov/images/imagerecords/57000/57752/land_shallow_topo_8192.tif
gdal_translate -a_srs EPSG:4326 -a_ullr -180 -90 180 90
land_shallow_topo_8192.tif marble.tif

gdal_translate -of GPKG marble.tif marble.gpkg -co
TILING_SCHEME=GoogleMapsCompatible
gdal_translate -r nearest -of GTIFF -tr 156543.0339280410 156543.0339280410
 marble.gpkg overview1.tif
gdaladdo -r near  marble.gpkg
gdal_translate -r nearest -of GTIFF -tr 156543.0339280410 156543.0339280410
 marble.gpkg overview2.tif
gdalwarp -r near -of GTIFF -tr 156543.0339280410 156543.0339280410
marble.gpkg overview3.tif


Why would the pixels shift because of the overview creation?


Thanks,
Roarke
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