[Qgis-user] Recognition of SRS in MapInfo-Files

[Bo Victor Thomsen]

Andreas -

As others on the list has mentioned, QGIS or rather, the underlying 
GDAL/OGR library has some issues with recognition of certain CRS 
definitions for Tab - files. In your specific case is it the EPGS:25832.

Try to look at the Layer CRS defintion of the tab file opened in QGIS . 
It probably contains a PROJ4 CRS like this:

+proj=utm +zone=32 +ellps=GRS80 +towgs84=0,0,0,-0,-0,-0,0 +units=m +no_defs

the "towgs84" parameter list contains several "minus zero" parameters. 
This is an error in GDAL/OGR. It has been corrected in GDAL ver 1.10 (I 
reported it to GDAL several months ago).

This error means, that QGIS 1.8 (which use a earlier version of 
GDAL/OGR) will assign a "custom CRS" definition for the new layer when 
it opens a tab-file with the EPGS:25832 CRS.

My hope is that QGIS 2.0 will use the latest GDAL library.

Regards

Bo Victor Thomsen
Aestas-GIS
Denamrk

Den 21-05-2013 09:37, Fischer, Andreas skrev:
> Recognition of SRS in MapInfo-Files
>
> Dear QGIS-Community,
>
> I'm preparing to get used QGIS 1.8 with Windows Vista/7.
>
> Since I do have to work with MapInfo-Professional as well and 
> sometimesusersstill have to transformon-the-fly from DHDN/GK3 
> (EPSG:31467) to ETRS89/UTM, Zone 32N (EPSG:25832) using NTv2 
> BETA2007.gsb there are some special issues.
>
> First I changed EPSG-definition in QGIS. I replaced +towgs84 parameter 
> with +nadgrid parameter and +wktext  in srs.db and 
> .\share\proj\epsg(+proj=utm +zone=32 +ellps=GRS80 
> +nadgrids=/path/BETA2007.gsb +wktext+units=m +no_defs). After I 
> deleted the SRS definition in .\share\gdal\pcs.csv everything works 
> fine. As soon as the SRS is recognized properly the transformation is 
> well done on the fly.Sousersdon't have to do anything to get the data 
> displayed in EPSG 25832with BETA2007. Fine to get to this point ...
>
> ... unfortunately Ido work with MapInfo TAB-files and the SRS is not 
> recognized as I expect. Every time I open a MapInfo TAB/MIFfile in 
> EPSG 31467or EPSG 25832QGIS doesn't matchtheequivalent build inSRS. 
> Insteadin caseofEPSG 31467a user defined SRS is build that makes use 
> of +towgs84 parameter again. So every time I do have to assign the 
> proper SRS to that layer (EPSG 31467) first.After 
> thaton-the-fly-transformation does work immediately.In caseofEPSG 
> 25832 the automatically defined SRS does have exactly the same 
> parameters as the build in definition ofQGIS. Anyway it doesn't match 
> to EPSG 25832.
>
> Why can't QGIS recognizetheSRS in MapInfo TAB-files?How does the 
> assignment of the SRS work?I assume that the user defined 
> parametersthat are used automaticallyare defined in some configuration 
> file. Maybe there is a possibility to change these settings.It would 
> be great to open a MapInfo-File in EPSG 31467 or in EPSG 25832andQGIS 
> does recognizethe SRSby itselfand match to the proper build in SRS!
>
> I will be glad to hear from you!
>
> Best regards
>
> Andreas
>
> Kreis Unna - Der Landrat
>
> Zentrale Datenverarbeitung
>
> Sachgebiet DV-Organisation
>
> Friedrich-Ebert-Straße 17
>
> 59425 Unna
>
> Fon 02 3 03 27-44 16
>
> Fax 0 23 03 27-28 96
>
> ___andreas.fischer at kreis-unna.de_<mailto:andreas.fischer at kreis-unna.de>
>
> ___www.kreis-unna.de_<http://www.kreis-unna.de>
>
> Denken Sie an die Umwelt. Pruefen Sie deshalb bitte,
> ob der Ausdruck dieser E-Mail wirklich notwendig ist.
>
>
> Diese E-Mail wurde beim Ausgang auf Viren geprueft. Wegen der
> potentiellen Gefahr auf den Uebertragungswegen wird zu einer
> Vireneingangskontrolle geraten. Eine Haftung für Virenfreiheit
> wird ausgeschlossen.
>
>
>
> _______________________________________________
> Qgis-user mailing list
> Qgis-user at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/qgis-user

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/qgis-user/attachments/20130521/9e1e3e0f/attachment.html>