[gdal-dev] help resampling raster to coarser scale

Anton Korosov anton.korosov at nersc.no
Fri Aug 5 02:27:41 EDT 2011


Hi Etienne!

What if you first process the original fine resolution image with a 
filter (low-pass, median, or manually created pixel function). Then the 
result, which is a fine resolution image but smoothed, could be 
resampled with the nearest neighbor.

Anton

On 08/05/2011 03:57 AM, Etienne wrote:
> Hi all,
>
>
> I am trying to resample a raster with categorical data (land surface vegetation/cover) from a high resolution (500m) to a coarser resolution.
>
> I would like to do something similar to what the GRASS operator r.resamp.stats does, using the modal category present in the higher resolution dataset to pick the value in the lower-resolution map.
> It seems that my only option using gdal_warp is nearest neighbor, which will pick the value nearest to the coarser pixel center (regardless of the most present category within the region).
>
> I would also like have a low-resolution map with the proportions of all land types (from the high resolution map).
>
> Any idea on how to accomplish what I want using gdal?  I am not familiar with GRASS, and would prefer to stick with GDAL if I can.  However, I am open to any suggestions.
>
> Many Thanks
> Etienne
> _______________________________________________
> gdal-dev mailing list
> gdal-dev at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/gdal-dev


More information about the gdal-dev mailing list