[GRASS-dev] i.pansharpen and Landsat 8

[Nikos Alexandris]

On Wednesday 23 of October 2013 12:48:16 Markus Neteler wrote:

> On Wed, Oct 23, 2013 at 10:09 AM, Yann Chemin <ychemin at gmail.com> wrote:
> > Using L8 with i.pansharpen gives nodata output, is it assuming 8-bit
> > datasets?

> I didn't have such problems, see

> http://courses.neteler.org/processing-landsat-8-data-in-grass-gis-7-rgb-comp
> osites-and-pan-sharpening/

Hi Markus.

I cannot confirm this :-(.  I only wish am completely wrong on this.  I tested 
with LC81260592013137LGN01.

All bands are visible when drawn in "d.mon wx0" and they (i.e. B2, B3, B5 and 
Pan) range in min=0, max=65535 (16-bit, unsigned). I MASKed the area of my 
interest. I then ran

i.pansharpen ms3=B5 ms2=B3 ms1=B2 pan=B8 output=sharpen sharpen=ihs --v


All of the derived sharpen_* maps are of min=NULL, max=NULL. If I rescale them 
to 8-bit, i.e.

r.rescale B2 out=B2_255 to=0,255
r.rescale B3 out=B2_255 to=0,255
r.rescale B3 out=B3_255 to=0,255
r.rescale B5 out=B5_255 to=0,255
!!:gs/B5/B8

it works fine. Both the data have a "valid" range, i.e. they are not NULLs, 
and they are drawn perfectly fine on "d.mon wx0". For the records:

r.info sharpen_green -r
min=0
max=158

r.info sharpen_red -r
min=0
max=175

r.info sharpen_blue -r
min=0
max=144

Nikos