Hi Even, Even Rouault wrote: > > Hi all, > > > > I am warping and upsampling an image from 4km to 30m using cubic resampling. > > I've been warping different sized windows from the source image like this: > > > > [snip] > > maybe try to add > > -et 0 > > and/or > > -wo XSCALE=133.33333333333334 -wo YSCALE=133.33333333333334 > > where 133.3333 = 4000 / 30 > > XSCALE/YSCALE are "un-documented" there: > https://github.com/OSGeo/gdal/blob/master/gdal/alg/gdalwarpkernel.cpp#L1120
Wow, thanks for this - would have never figured this out on my own. For me, both -et and the two -wo flags were necessary to make the reprojections from the full window and the row be equivalent. Using the -wo flags on their own gets pretty close (~0.5% percent difference in pixel values in my test), but -et on its own was still substantially different (~7% percent differences in pixel values). thanks, matt _______________________________________________ gdal-dev mailing list [email protected] https://lists.osgeo.org/mailman/listinfo/gdal-dev
