[postgis-devel] spatial_ref_sys maintainance

[Even Rouault]

Paul,

Le jeudi 28 janvier 2016 17:18:47, Paul Ramsey a écrit :
> EPSG:2065
> https://lists.osgeo.org/pipermail/postgis-devel/2012-July/021533.html

That one is a tough one. I've requested help from our Czech friends : 
https://lists.osgeo.org/pipermail/gdal-dev/2016-January/043586.html

> 
> EPSG:3844
> https://lists.osgeo.org/pipermail/postgis-devel/2012-June/020890.html
> 
> This last one looks like it could be an error in the EPSG database
> itself, fixable far upstream.

I think the EPSG database itself is OK. What is probably not OK is the process 
that derives the +towgs84. This is a know issue in the libgeotiff script. The 
EPSG database offers various datum shifts for a given datum, with different 
validity areas. epsg-registry.org shows that the area of validity for 
EPSG:3844 is Romania, but the underlying GEOGCS (EPSG:4179) has a broader area 
of validity ("Europe - onshore - eastern - S-42(58)" which covers Albania, 
Bulgaria, Czech Republic, Germany (former DDR), Hungary, Poland, Romania and 
Slovakia.). Poland is likely the largest country in that area, hence the 
selected datum shift which is relevant for EPSG:4179, but not for EPSG:3844 
built on it. 
The manual override might be an interim solution. A better solution would be 
to fix the selection logic.

Even

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