[GRASS-user] Problems running g.gui.gcp

Fri Oct 23 05:17:39 PDT 2015

On Fri, Oct 23, 2015 at 1:37 PM, Anna Petrášová <kratochanna at gmail.com>
wrote:

>
> On Oct 23, 2015 6:04 AM, "Johannes Radinger" <johannesradinger at gmail.com>
> wrote:
> >
> >
> >
> > On Fri, Oct 23, 2015 at 11:19 AM, Moritz Lennert <
> mlennert at club.worldonline.be> wrote:
> >>
> >> On 23/10/15 10:56, Johannes Radinger wrote:
> >>>
> >>>
> >>>
> >>> On Fri, Oct 23, 2015 at 10:17 AM, Moritz Lennert
> >>> <mlennert at club.worldonline.be <mailto:mlennert at club.worldonline.be>>
> wrote:
> >>>
> >>>     On 22/10/15 16:25, Johannes Radinger wrote:
> >>>
> >>>         Dear GRASS users,
> >>>
> >>>         Today I wanted to try the georectification tool g.gui.gcp in
> >>>         GRASS 7 for
> >>>         the first time. I was basically following the description on
> the
> >>>         GRASS
> >>>         wiki (https://grasswiki.osgeo.org/wiki/Georeferencing). In
> >>>         particular, I
> >>>         have a photograph from my camera with known reference points
> which I
> >>>         load into an unprojected XY location. My target location should
> >>>         also be
> >>>         a XY location as the picture is taken from a "virtual"
> coordinate
> >>>         system. Inside my target XY-location I try to open g.gui.gcp
> and
> >>>         select
> >>>         raster, and the location and mapset where my photograph is
> >>>         stored. When
> >>>         I want to click next I get following error/message: "You must
> >>>         select a
> >>>         valid location and mapset in order to continue" and I can't
> >>>         proceed with
> >>>         the rectification. Just this GUI message appears, no
> >>>         error/warning in
> >>>         the grass console etc. I am puzzled how to interpret that? What
> >>>         is wrong
> >>>         with the location/mapset? The mapset I've selected is existing
> >>>         (I can
> >>>         select it from the dropdown menu). I tried to select any other
> >>>         location/mapset but receive always the same message.
> >>>
> >>>
> >>>
> >>>     Georectification is for georeferencing to a projected system. It
> >>>     does not make sense to georeference to an XY-location.
> >>>
> >>>     I see two options for you:
> >>>
> >>>     - Import you image directely into the target region and use
> r.region
> >>>     to adjust its boundary coordinates
> >>>     - Define your own projection system to fit your needs.
> >>>
> >>>
> >>> So far as I understand georectification and orthorectification in
> >>> particular is to rectify a picture/photo/image based on spatially
> >>> defined ground control points which might not be done by just adjusting
> >>> the boundary coordinates. BTW I also tried the European LAEA coordinate
> >>> system (EPSG 3035) as a target location which is not working either
> here
> >>> in my machine/setup (same message as already mentioned). Here
> >>> (
> https://www.dropbox.com/s/snjzd8eu7b8115k/2015-10-22%2015.26.30.jpg?dl=0)
> >>> you can find a a photo (*.jpg) which is an "areal" photo with known 3d
> >>> coordinates for the single points (ground control points). I think this
> >>> example clarifies and illustrates what I intend to do and why the
> target
> >>> system can also be a XY location in my opinion. A rectification of this
> >>> image should make the lines of the grid more or less parallel. Or do I
> >>> get something completely wrong?
> >>
> >>
> >> Actually, I was wrong: I don't get any complaint trying to use
> g.gui.gcp to georectify from XY to XY. So there seems to be an issue with
> your XY locations.
> >>
> >> Have you tried recreating the locations from scratch ?
> >
> >
> > Your results look really reasonable.... that's what I was looking for...
> >
> > Actually, both XY locations are created from scratch (via the location
> wizzard)
> > I get following output for both XY locations:
> >
> > g.proj -p
>
> > XY location (unprojected)
> >
> > I tried to start the GCP manager from within different other locations
> (e.g. laea, datum: etrs89) and selecting different source location (e.g.
> WGS84)....however I always get the same message. So I guess this is not
> specifically related to my location but rather to the GCP manager/WX GUI?
> As I don't get an error message it is difficult to judge what is going
> wrong in my case...
> >
> > I just looked up the source code and the error message seems to be
> related to follwoing line:
> >
> https://trac.osgeo.org/grass/browser/grass/branches/releasebranch_7_0/gui/wxpython/gcp/manager.py#L399
> > As far as I understand, this error message is only given if no
>  location/mapset is provided; however that is not the case here. Maybe my
> selection of the location/mapset via the GUI does not get parsed
> further....?
> >
> > Strange that orthorectification from one XY to antother XY location
> works on other machines but not on mine.
> >
> > PS: As an important side note: I am working on Ubuntu which is installed
> on a virtual machine (VMWare) on our server. I remotely connect to this
> virtual machine via RDP
>
> I noticed you have strange version of wxpython. Any chance you could test
> on machine with version 2.8.12.0 or a stable 3 version?
>
Indeed, I upgraded now to wxpython 3.0.1.0 and the GCP manager is working
now! YES!. At least my location/mapset settings are accepted and I get to
the next step. So now I can actually test and try the GCP manager.
Thanks for your help!

/Johannes

> Anna
> >
> >>
> >>
> >> Moritz
> >
> >
> >
> > _______________________________________________
> > grass-user mailing list
> > grass-user at lists.osgeo.org
> > http://lists.osgeo.org/mailman/listinfo/grass-user
>
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