[GRASS-user] Difference between r.series; r.patch

[Nikos Alexandris]

katrin wrote:

> > I have a sequence of satellite images (e.g 1 in the north, other in the
> > center and other in south) that I want to merge in a single image. I
> > found three GRASS methodologies:
> > - r.series
> > - r.patch
> > - i.image.mosaic.
> > Which one is the best to perform what I need?

Hamish:
 
> I'm not really familiar with i.image.mosaic, but r.patch would be the
> one to use if you have three satellite images taken in sequence which
> you wish to merge into a single image.
 
> r.series is usually used to merge overlapping maps, r.patch to merge
> adjoining maps.
 
> to make r.patch easier, you can do:
>  g.region rast=map1,map2,map3
 
> to extend the region settings to the outer bounds of all three maps.

Something critical, if I am not wrong: the order of "map1,map2,map3" is 
important (when patching overlaping maps). Check the r.patch manual.

Nikos