[Qgis-user] Raster VRT SRS syntax

[Even Rouault]

Le mercredi 29 octobre 2014 14:37:57, Zoltan Szecsei a écrit :
> On 2014/10/29 14:37, Even Rouault wrote:
> > Perhaps the following can work too (untested) provided a 'ZANGI' file
> > exists in the PROJ.4 resource directory that contains the 'epsg' file,
> > grids, and other files. <SRS>+init=ZANGI:ZANGI:HBKNO27</srs>
> 
> Hi Even,
> When I let gdalbuildvrt simply add its own SRS from the image files,

So, what SRS does it put ? Why not just keeping it ? I'm confused.

> when I load that VRT into QGIS, it loads correctly without asking me to
> specify the CRS for that layer.
> 
> However
> 
> When I query that layer to see its CRS, it shows me a Generated CRS,
> even though the HBKNO27 is in the known list (see screenshot below).
> I want the user to see the named CRS and not the generated (more
> confusing) CRS.
> 
> The first few lines of my VRT is as follows, yet I still get the pop-up
> asking me to set the CRS.

Likely the logic of QGIS that tries to match the SRS it gets from GDAL with 
the ones it has in his DB doesn't manage to do a match.

> (I'm still trying different permutations, but I just wanted to give
> feedback)
> Regards,
> Zoltan
> 
>     <VRTDataset rasterXSize="24455" rasterYSize="22659">
>        <SRS>+init=ZANGI:ZANGI:HBKNO27</SRS>
>        <GeoTransform>  9.5763066019661390e+04, 5.0000000000000000e-01,
>     0.0000000000000000e+00, -2.5336277500000000e+06,
>     0.0000000000000000e+00, -5.0000000000000000e-01</GeoTransform>
>        <VRTRasterBand dataType="Byte" band="1">
>     <NoDataValue>0.00000000000000E+00</NoDataValue>
>          <ColorInterp>Red</ColorInterp>
>          <SimpleSource>

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