[GRASS-user] problems with i.rectify

GRASS GRASS user
1

Hi everybody!
I’m a rather new GRASS user and encountered problems using i.rectify to rectify aerial images taken from helicopter. 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
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!!

/Martina

···

–

Martina Schäfer, PhD
GIS och bekämpningsansvarig forskare
Biologisk Myggkontroll Uppsala universitet, Inst. f ekologi och evolution;
populationsbiologi och naturvårdsbiologi

Norbyvägen 18D, 752 36 Uppsala
Tel: 018-4712674, 070-4250605
Fax: 018-4716424
http://www.popbiol.ebc.uu.se/
www.mygg.se

2

Hi Martin,

On Wed, Apr 1, 2009 at 9:11 AM, Martina Schäfer
<Martina.Schafer@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/

3

Hello Markus,

thanks for the reply! And thanks for the tip on i.orto.photo, I will read through your article!

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?
  

Well, the space was my fault and a typing mistake, it really says NN1_2.red1257, so no error there.

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.
  

I looked in the group folder and found a file REF where all bands are properly named. Was that the file you meant?
The group is defined in the XY location. In the projected location it does not exist prior to rectifying.

BTW: which GRASS version and which operating system?
  

I'm using GRASS 6.3. downloaded from http://grass.bologna.enea.it/ on Mac OS X 10.5.6

Best,
Martina

4

hi Martina,

On Thu, Apr 2, 2009 at 9:28 AM, Martina Schäfer
<Martina.Schafer@ebc.uu.se> wrote:

Hello Markus,

thanks for the reply! And thanks for the tip on i.orto.photo, I will read
through your article!

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?

Well, the space was my fault and a typing mistake, it really says
NN1_2.red1257, so no error there.

ah ok, perfect.

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.

I looked in the group folder and found a file REF where all bands are
properly named. Was that the file you meant?

Yes, fine.

The group is defined in the XY location. In the projected location it does
not exist prior to rectifying.

BTW: which GRASS version and which operating system?

I'm using GRASS 6.3. downloaded from http://grass.bologna.enea.it/ on Mac OS
X 10.5.6

I recall that we fixed some issues later. Could you upgrade to 6.4RC3
instead?
http://grass.osgeo.org/download/index.php#g64x

If it still fails we may be able to fix it for 6.4.0 final.

best
Markus

5

Hi again!

I installed GRASS 6.4 and first I got the same error. Then, I tried with defining a new group and subgroup in the XY mapset (not using the one that is created when importing) and with that it worked!! However, I also tried using wxpython, which looks neat, but there I get the error message that the group does not exist (but it certainly does).

Best,
Martina

Markus Neteler skrev:

hi Martina,

On Thu, Apr 2, 2009 at 9:28 AM, Martina Schäfer
<Martina.Schafer@ebc.uu.se> wrote:
  

Hello Markus,

thanks for the reply! And thanks for the tip on i.orto.photo, I will read
through your article!
    

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?

Well, the space was my fault and a typing mistake, it really says
NN1_2.red1257, so no error there.
    
ah ok, perfect.

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.

I looked in the group folder and found a file REF where all bands are
properly named. Was that the file you meant?
    
Yes, fine.

The group is defined in the XY location. In the projected location it does
not exist prior to rectifying.

BTW: which GRASS version and which operating system?

I'm using GRASS 6.3. downloaded from http://grass.bologna.enea.it/ on Mac OS
X 10.5.6
    
I recall that we fixed some issues later. Could you upgrade to 6.4RC3
instead?
http://grass.osgeo.org/download/index.php#g64x

If it still fails we may be able to fix it for 6.4.0 final.

best
Markus

6

Hi ,
just want to add that when I rectified the next image the same error appeared again - the first band in the group is not rectified as it is "not found". I lured the programme now by adding an additional band from a similar image to the group and put it in first place , so that this band is not rectified/found but the three bands of my image are...

regards,
Martina

Martina Schäfer skrev:

Hi again!

I installed GRASS 6.4 and first I got the same error. Then, I tried with defining a new group and subgroup in the XY mapset (not using the one that is created when importing) and with that it worked!! However, I also tried using wxpython, which looks neat, but there I get the error message that the group does not exist (but it certainly does).

Best,
Martina

Markus Neteler skrev:

hi Martina,

On Thu, Apr 2, 2009 at 9:28 AM, Martina Schäfer
<Martina.Schafer@ebc.uu.se> wrote:

Hello Markus,

thanks for the reply! And thanks for the tip on i.orto.photo, I will read
through your article!
   

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?

Well, the space was my fault and a typing mistake, it really says
NN1_2.red1257, so no error there.
    
ah ok, perfect.

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.

I looked in the group folder and found a file REF where all bands are
properly named. Was that the file you meant?
    
Yes, fine.

The group is defined in the XY location. In the projected location it does
not exist prior to rectifying.

BTW: which GRASS version and which operating system?

I'm using GRASS 6.3. downloaded from http://grass.bologna.enea.it/ on Mac OS
X 10.5.6
    
I recall that we fixed some issues later. Could you upgrade to 6.4RC3
instead?
http://grass.osgeo.org/download/index.php#g64x

If it still fails we may be able to fix it for 6.4.0 final.

best
Markus