[gdal-dev] Rv: How to determine +towgs84

[jose perez]

Hello.


How to determine the +towgs84 parameters required to do accurate coordinate 
transformations? I know there's a file (named epsg) which contains a list, but 
in order to use I think I need the EPSG code. Then, how to obtain EPSG code from 
(for ecample) this WKT?:

PROJCS["UTM Zone 30, Northern Hemisphere",GEOGCS["Geographic Coordinate  
System",
DATUM["EUROPEAN_1950_(SPAIN_AND_PORTUGAL)",
SPHEROID["International_1909_Hayford_Intl_1924",6378388,297.0000000284015]],
PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]],
PROJECTION["Transverse_Mercator"],
PARAMETER["latitude_of_origin",0],
PARAMETER["central_meridian",-3],
PARAMETER["scale_factor",0.9996],
PARAMETER["false_easting",500000],
PARAMETER["false_northing",0],
UNIT["Meter",1]]

AutoIdentifyEPSG() is unable to find out the EPSG code, so I can't figure out 
how to get the TOWGS84 parameters.

Any help appreciated.
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