[GRASS-user] problems with i.rectify

[Markus Neteler]

Hi Martin,

On Wed, Apr 1, 2009 at 9:11 AM, Martina Schäfer
<Martina.Schafer at ebc.uu.se> wrote:
> Hi everybody!
> I'm a rather new GRASS user and encountered problems using i.rectify to
> rectify aerial images taken from helicopter.

[Just a note:
 if you have approx. camera info and a DEM, you can even ortho-rectify them
 with i.ortho.photo, see
 M. Neteler, D. Grasso, I. Michelazzi, L. Miori, S. Merler, and C.
Furlanello, 2005:
 An integrated toolbox for image registration, fusion and
classification. International
 Journal of Geoinformatics, 1(1), pp. 51-61
 http://ojs.info.gscc.osaka-cu.ac.jp/IJG/index.php/IJG/article/view/103/42
]

> I've followed the instructions
> and everything's working fine except that the red band is not included. In
> the output it says :
> Rectified input file NN1_2.red will be saved as NN1_2.red 1257

I see a suspicious white space before 1257.
Where does it come from? Could it be that it crept
in when defining the group?

> unable to find NN1_2.red1257 in permanent.
>
> it nevertheless continues with:
> Rectify NN1_2.red....into NN1_2.red1257...
> complete
>
> the green and blue band are rectified without problems and look fine.
> Any help is greatly appreciated!!

In the mapset there is a group/ directory in which the
group is defined (ASCII file). The easiest way is to check
there/fix if the red channel was defined properly.

BTW: which GRASS version and which operating system?

best
Markus

-- 
Markus Neteler
Foundation Edmund Mach (FEM) - Research and Innovation Centre
Environment and Natural Resources Area
GIS and Remote Sensing Unit, Trento, Italy
Web:  http://gis.fem-environment.eu/