On Mar 4, 2008, at 10:00 AM, grass-dev-request@lists.osgeo.org wrote:
Date: Tue, 4 Mar 2008 17:04:27 +0100
From: "Nicolas MERLET" <admin@merletn.org>
Subject: [GRASS-dev] image rectification from command line only ?
To: <grass-dev@lists.osgeo.org>
Message-ID: <018801c87e11$6d0d9690$6642000a@NICOLAS>
Content-Type: text/plain; charset="us-ascii"
hi all,
i need to rectify an image automatically (i assume using i.points and
i.rectify). as far as i've been able to see, i.points is to use in graphical
monitor mode ? so does anyone know how to use it from the command line (and
only from the command line) ?
thanks for helping...
nicolas
i.points lets a user interactively set ground control points (GCPs) for an unrectified image, using a rectified image. This particular process cannot be automated since it is interactive by definition.
However, if you already know the ground coordinates of a set of xy points for an image, you can build a POINTS file and i.rectify will georectify the image from the command line.
-----Original Message-----
From: grass-dev-bounces@lists.osgeo.org
[mailto:grass-dev-bounces@lists.osgeo.org] On Behalf Of Michael Barton
Sent: Tuesday, March 04, 2008 6:38 PM
To: grass-dev@lists.osgeo.org
Subject: Re: [GRASS-dev] image rectification from command line only ?
On Mar 4, 2008, at 10:00 AM, grass-dev-request@lists.osgeo.org wrote:
> Date: Tue, 4 Mar 2008 17:04:27 +0100
> From: "Nicolas MERLET" <admin@merletn.org>
> Subject: [GRASS-dev] image rectification from command line only ?
> To: <grass-dev@lists.osgeo.org>
> Message-ID: <018801c87e11$6d0d9690$6642000a@NICOLAS>
> Content-Type: text/plain; charset="us-ascii"
>
>
> hi all,
>
> i need to rectify an image automatically (i assume using
i.points and
> i.rectify). as far as i've been able to see, i.points is to use in
> graphical
> monitor mode ? so does anyone know how to use it from the command
> line (and
> only from the command line) ?
>
> thanks for helping...
>
> nicolas
i.points lets a user interactively set ground control points (GCPs)
for an unrectified image, using a rectified image. This particular
process cannot be automated since it is interactive by definition.
However, if you already know the ground coordinates of a set of xy
points for an image, you can build a POINTS file and i.rectify will
georectify the image from the command line.
Michael
that would be enough as my GCP are pre-calculated. however i haven't found
any documentation about the POINTS files structure. where can i find it ? (i
just have http://grass.itc.it/gdp/html_grass63/i.rectify.html)
moreover, assuming we use i.rectify there's no paramater to give points, so
i suppose i just have to copy my POINT file in my image group so that
i.rectify will be able to find it ?
I don't know of any documentation for this. I guess just look at existing examples. Perhaps make a test case and rectify them in. That's what I did when working out the format for the GUI versions of this. You'll have to make a group and put the file into the group folder.
Michael
______________________________
Michael Barton, Professor
Professor of Anthropology
Director of Graduate Studies
School of Human Diversity & Social Change
Center for Social Dynamics & Complexity
Arizona State University
Tempe, AZ 85287-2402
USA
On Mar 4, 2008, at 11:32 AM, Nicolas MERLET wrote:
-----Original Message-----
From: grass-dev-bounces@lists.osgeo.org
[mailto:grass-dev-bounces@lists.osgeo.org] On Behalf Of Michael Barton
Sent: Tuesday, March 04, 2008 6:38 PM
To: grass-dev@lists.osgeo.org
Subject: Re: [GRASS-dev] image rectification from command line only ?
On Mar 4, 2008, at 10:00 AM, grass-dev-request@lists.osgeo.org wrote:
Date: Tue, 4 Mar 2008 17:04:27 +0100
From: "Nicolas MERLET" <admin@merletn.org>
Subject: [GRASS-dev] image rectification from command line only ?
To: <grass-dev@lists.osgeo.org>
Message-ID: <018801c87e11$6d0d9690$6642000a@NICOLAS>
Content-Type: text/plain; charset="us-ascii"
hi all,
i need to rectify an image automatically (i assume using
i.points and
i.rectify). as far as i've been able to see, i.points is to use in
graphical
monitor mode ? so does anyone know how to use it from the command
line (and
only from the command line) ?
thanks for helping...
nicolas
i.points lets a user interactively set ground control points (GCPs)
for an unrectified image, using a rectified image. This particular
process cannot be automated since it is interactive by definition.
However, if you already know the ground coordinates of a set of xy
points for an image, you can build a POINTS file and i.rectify will
georectify the image from the command line.
Michael
that would be enough as my GCP are pre-calculated. however i haven't found
any documentation about the POINTS files structure. where can i find it ? (i
just have http://grass.itc.it/gdp/html_grass63/i.rectify.html)
moreover, assuming we use i.rectify there's no paramater to give points, so
i suppose i just have to copy my POINT file in my image group so that
i.rectify will be able to find it ?
So that's what I'll do. I let you know if I'm successful.
Thank you so much. Have a nice day.
Nicolas
-----Original Message-----
From: Michael Barton [mailto:michael.barton@asu.edu]
Sent: Tuesday, March 04, 2008 7:59 PM
To: Nicolas MERLET
Cc: grass-dev@lists.osgeo.org
Subject: Re: [GRASS-dev] image rectification from command line only ?
I don't know of any documentation for this. I guess just look at
existing examples. Perhaps make a test case and rectify them in.
That's what I did when working out the format for the GUI
versions of
this. You'll have to make a group and put the file into the group
folder.
Michael
______________________________
Michael Barton, Professor
Professor of Anthropology
Director of Graduate Studies
School of Human Diversity & Social Change
Center for Social Dynamics & Complexity
Arizona State University
Tempe, AZ 85287-2402
USA
On Mar 4, 2008, at 11:32 AM, Nicolas MERLET wrote:
>
>
>> -----Original Message-----
>> From: grass-dev-bounces@lists.osgeo.org
>> [mailto:grass-dev-bounces@lists.osgeo.org] On Behalf Of Michael
>> Barton
>> Sent: Tuesday, March 04, 2008 6:38 PM
>> To: grass-dev@lists.osgeo.org
>> Subject: Re: [GRASS-dev] image rectification from command
line only ?
>>
>>
>>
>> On Mar 4, 2008, at 10:00 AM,
grass-dev-request@lists.osgeo.org wrote:
>>
>>> Date: Tue, 4 Mar 2008 17:04:27 +0100
>>> From: "Nicolas MERLET" <admin@merletn.org>
>>> Subject: [GRASS-dev] image rectification from command line only ?
>>> To: <grass-dev@lists.osgeo.org>
>>> Message-ID: <018801c87e11$6d0d9690$6642000a@NICOLAS>
>>> Content-Type: text/plain; charset="us-ascii"
>>>
>>>
>>> hi all,
>>>
>>> i need to rectify an image automatically (i assume using
>> i.points and
>>> i.rectify). as far as i've been able to see, i.points is to use in
>>> graphical
>>> monitor mode ? so does anyone know how to use it from the command
>>> line (and
>>> only from the command line) ?
>>>
>>> thanks for helping...
>>>
>>> nicolas
>>
>> i.points lets a user interactively set ground control points (GCPs)
>> for an unrectified image, using a rectified image. This particular
>> process cannot be automated since it is interactive by definition.
>>
>> However, if you already know the ground coordinates of a set of xy
>> points for an image, you can build a POINTS file and i.rectify will
>> georectify the image from the command line.
>>
>> Michael
>>
>
> that would be enough as my GCP are pre-calculated. however
i haven't
> found
> any documentation about the POINTS files structure. where
can i find
> it ? (i
> just have http://grass.itc.it/gdp/html_grass63/i.rectify.html)
>
> moreover, assuming we use i.rectify there's no paramater to give
> points, so
> i suppose i just have to copy my POINT file in my image
group so that
> i.rectify will be able to find it ?
>
> again, thank you very much for helping !
>
> Nicolas
>
>
>
>
>
>
i.points lets a user interactively set ground control points (GCPs)
for an unrectified image, using a rectified image. This particular
process cannot be automated since it is interactive by definition.
that would be enough as my GCP are pre-calculated. however i haven't
found any documentation about the POINTS files structure. where can
i find it ?
it's self documenting, create a dummy POINTS file and look in it.
It's an ASCII file with labeled columns.
moreover, assuming we use i.rectify there's no paramater to give
points, so i suppose i just have to copy my POINT file in my image
group so that i.rectify will be able to find it ?
yes.
another way, using GDAL, is to add in GCPs to a GeoTIFF's metadata with
gdal_translate, then use gdalwarp to rectify the image. AFAICT gdalwarp
uses the rectification code (lineage) as i.rectify, but gdalwarp is
much faster.
check out i.points.auto: