[gdal-dev] gdalwarp - banded overviews

[Frank Warmerdam]

On Wed, May 21, 2008 at 5:47 PM, Alex Bowen (Contractor)
<bowen at enews.nrl.navy.mil> wrote:
> I'm working with gdalwarp to re-project some fairly large imagery sources
> that have multiple overviews per band (mostly MrSID data).  Is there any way
> to force gdalwarp to use a specified overview layer for its processing, or a
> way to have it 'auto-calculate' the most efficient level?  I have looked
> through the code in gdalwarp.cpp/gdalwarpoperation.cpp and it doesn't seem
> to take overviews into account.
>
>
>
> Either way, this would be incredibly more efficient when warping extremely
> images down to lower resolutions – you don't really need to read the 'raw'
> overview in such cases, just the one that has a comparable lat/lon
> resolution.

Alex,

As you suspect, currently gdalwarp cannot take advantage of
overviews.

I would agree that using the overviews would be a good idea
in some cases, though it will interfere with the purity of the
resampling kernels being applied.

Best regards,
-- 
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