[GRASS-user] r.neighbor circular mask VS r.buffer on single pixel

[Enrico Gallo]

Dear list,

I am working on 50m resolution DEM making analysis on 1 km radius
area, in order to find local minimum.
To begin, I used r.neighbor with a circular mask , size 41 pixel.
I repeated a similar analysis (adding another filter) parsing r.univar
on each 1km buffer around each pixel (using r.mask)

Just for the sake of precision, I also tested my routine not
considering the added filter and I notice a few cases where the two
results slightly differ, probably due a difference between r.neighbor
circular mask and r.buffer output used as mask: as you can see in the
attached image, the blue pixel is the minimum using buffer, the red
one using r.neighbor

Does it make sense? or the two analysis should return the same result
as the two masks should have the same shape?


Enrico
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