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On Oct 23, 2015 6:04 AM, "Johannes Radinger" <<a href="mailto:johannesradinger@gmail.com">johannesradinger@gmail.com</a>> wrote:<br>
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> On Fri, Oct 23, 2015 at 11:19 AM, Moritz Lennert <<a href="mailto:mlennert@club.worldonline.be">mlennert@club.worldonline.be</a>> wrote:<br>
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>> On 23/10/15 10:56, Johannes Radinger wrote:<br>
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>>> On Fri, Oct 23, 2015 at 10:17 AM, Moritz Lennert<br>
>>> <<a href="mailto:mlennert@club.worldonline.be">mlennert@club.worldonline.be</a> <mailto:<a href="mailto:mlennert@club.worldonline.be">mlennert@club.worldonline.be</a>>> wrote:<br>
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>>> On 22/10/15 16:25, Johannes Radinger wrote:<br>
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>>> Dear GRASS users,<br>
>>><br>
>>> Today I wanted to try the georectification tool g.gui.gcp in<br>
>>> GRASS 7 for<br>
>>> the first time. I was basically following the description on the<br>
>>> GRASS<br>
>>> wiki (<a href="https://grasswiki.osgeo.org/wiki/Georeferencing">https://grasswiki.osgeo.org/wiki/Georeferencing</a>). In<br>
>>> particular, I<br>
>>> have a photograph from my camera with known reference points which I<br>
>>> load into an unprojected XY location. My target location should<br>
>>> also be<br>
>>> a XY location as the picture is taken from a "virtual" coordinate<br>
>>> system. Inside my target XY-location I try to open g.gui.gcp and<br>
>>> select<br>
>>> raster, and the location and mapset where my photograph is<br>
>>> stored. When<br>
>>> I want to click next I get following error/message: "You must<br>
>>> select a<br>
>>> valid location and mapset in order to continue" and I can't<br>
>>> proceed with<br>
>>> the rectification. Just this GUI message appears, no<br>
>>> error/warning in<br>
>>> the grass console etc. I am puzzled how to interpret that? What<br>
>>> is wrong<br>
>>> with the location/mapset? The mapset I've selected is existing<br>
>>> (I can<br>
>>> select it from the dropdown menu). I tried to select any other<br>
>>> location/mapset but receive always the same message.<br>
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>>> Georectification is for georeferencing to a projected system. It<br>
>>> does not make sense to georeference to an XY-location.<br>
>>><br>
>>> I see two options for you:<br>
>>><br>
>>> - Import you image directely into the target region and use r.region<br>
>>> to adjust its boundary coordinates<br>
>>> - Define your own projection system to fit your needs.<br>
>>><br>
>>><br>
>>> So far as I understand georectification and orthorectification in<br>
>>> particular is to rectify a picture/photo/image based on spatially<br>
>>> defined ground control points which might not be done by just adjusting<br>
>>> the boundary coordinates. BTW I also tried the European LAEA coordinate<br>
>>> system (EPSG 3035) as a target location which is not working either here<br>
>>> in my machine/setup (same message as already mentioned). Here<br>
>>> (<a href="https://www.dropbox.com/s/snjzd8eu7b8115k/2015-10-22%2015.26.30.jpg?dl=0">https://www.dropbox.com/s/snjzd8eu7b8115k/2015-10-22%2015.26.30.jpg?dl=0</a>)<br>
>>> you can find a a photo (*.jpg) which is an "areal" photo with known 3d<br>
>>> coordinates for the single points (ground control points). I think this<br>
>>> example clarifies and illustrates what I intend to do and why the target<br>
>>> system can also be a XY location in my opinion. A rectification of this<br>
>>> image should make the lines of the grid more or less parallel. Or do I<br>
>>> get something completely wrong?<br>
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>> 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.<br>
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>> Have you tried recreating the locations from scratch ?<br>
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> Your results look really reasonable.... that's what I was looking for...<br>
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> Actually, both XY locations are created from scratch (via the location wizzard)<br>
> I get following output for both XY locations: <br>
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> g.proj -p <br>
> XY location (unprojected)<br>
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> 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...<br>
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> I just looked up the source code and the error message seems to be related to follwoing line:<br>
> <a href="https://trac.osgeo.org/grass/browser/grass/branches/releasebranch_7_0/gui/wxpython/gcp/manager.py#L399">https://trac.osgeo.org/grass/browser/grass/branches/releasebranch_7_0/gui/wxpython/gcp/manager.py#L399</a><br>
> 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....?<br>
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> Strange that orthorectification from one XY to antother XY location works on other machines but not on mine.<br>
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> 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<br></p>
<p dir="ltr">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?</p>
<p dir="ltr">Anna<br>
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>> Moritz<br>
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