[gdal-dev] Working with overviews (in python)

[Even Rouault]

Hi,

As Frank said in his email, there's work needed in GDAL internals to do what 
you want properly. But I've just found a workaround that might work if you 
only plan to use the produced (external) overviews with GDAL. The trick is to 
generate the overviews by hand with gdalwarp.

Let's say that your input file is 1024x1024 large.
Then try :
gdalwarp -rcs -ts 512 512 input.tif input.tif.ovr
gdalwarp -rcs -ts 256 256 input.tif.ovr input.tif.ovr.ovr
gdalwarp -rcs -ts 128 128 input.tif.ovr.ovr input.tif.ovr.ovr.ovr

By chance, GDAL can handle overviews of overviews...

Best regards,
Even