[gdal-dev] help with resampling via python

[Frank Warmerdam]

Jose Gomez-Dans wrote:
> Hi Klokan,
> 
> 2009/4/1 Klokan Petr Přidal <klokan at klokan.cz <mailto:klokan at klokan.cz>>
> 
>     gdal.RegenerateOverview() with 'average' and 'mode' algorithms.
>     and
>     gdal.ReprojectImage() with 'bilinear','cubic','cubicspline' and
>     'lanczos' algorithms.
> 
> 
> That's quite cool, but does RegenerateOverview() take into account 
> NODATA values when doing the 'mode' or 'average'? It would be nice if it 
> could ignore them!

Jose,

It appears based on review of the code that the "AVERAGE" overview
generation algorithm does ignore pixels determined to be nodata.

I have not experimentally confirmed this.

Best regards,
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