[Gdal-dev] reprojecting DEM&TM

[Frank Warmerdam]

Maciek Sieczka wrote:
> hello all!
> 
> could somebody tell me which method -rn, rb, -rc or -rcs should I use for
> DEM and which for data like e.g. Landsat TM reprojecting

Maciek,

I would suggest -rb for DEMs, and one of the cubic kernsls for landsat data.
Of course, there are various factors that you should take into account.

Using -rb (bilinear) for the DEM will perform local averaging of the nearby
pixel values in the source.  This give reasonable results without introducing
any risky "overshoot" effects you might see with cubic that could be
disturbing for analysis or visualization in a DEM.

The cubic should in theory do better at preserving edges and general
visual crispness than using bilinar or nearest neighbour.  However, if you
are wanting to do analysis with the landsat (such as multispectral classification)
I would suggest just using -rn (nearest neighbour) so as to avoid causing odd
effects to the spectral values.

Best regards,
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