I’m noticing subtle differences between the WKT representations for a given
projection when consulting spatialreference.org, epsg.io, and the output from
gdalinfo on an orthorectified raster. For example, for Africa Albers (ESRI code
102022):
1) gdalinfo output for a raster, CRS set with “SetFromUserInput(‘ESRI:102022’)”:
PROJCRS["Africa_Albers_Equal_Area_Conic",
BASEGEOGCRS["WGS 84",
DATUM["World Geodetic System 1984",
ELLIPSOID["WGS 84",6378137,298.257223563,
LENGTHUNIT["metre",1]]],
PRIMEM["Greenwich",0,
ANGLEUNIT["degree",0.0174532925199433]],
ID["EPSG",4326]],
CONVERSION["Albers Equal Area",
METHOD["Albers Equal Area",
ID["EPSG",9822]],
PARAMETER["Latitude of false origin",0,
ANGLEUNIT["degree",0.0174532925199433],
ID["EPSG",8821]],
PARAMETER["Longitude of false origin",25,
ANGLEUNIT["degree",0.0174532925199433],
ID["EPSG",8822]],
PARAMETER["Latitude of 1st standard parallel",20,
ANGLEUNIT["degree",0.0174532925199433],
ID["EPSG",8823]],
PARAMETER["Latitude of 2nd standard parallel",-23,
ANGLEUNIT["degree",0.0174532925199433],
ID["EPSG",8824]],
PARAMETER["Easting at false origin",0,
LENGTHUNIT["metre",1],
ID["EPSG",8826]],
PARAMETER["Northing at false origin",0,
LENGTHUNIT["metre",1],
ID["EPSG",8827]]],
CS[Cartesian,2],
AXIS["easting",east,
ORDER[1],
LENGTHUNIT["metre",1,
ID["EPSG",9001]]],
AXIS["northing",north,
ORDER[2],
LENGTHUNIT["metre",1,
ID["EPSG",9001]]]]
2) WKT for ESRI 102022 at
https://spatialreference.org/ref/esri/102022/prettywkt/
PROJCS["Africa_Albers_Equal_Area_Conic",
GEOGCS["GCS_WGS_1984",
DATUM["WGS_1984",
SPHEROID["WGS_1984",6378137,298.257223563]],
PRIMEM["Greenwich",0],
UNIT["Degree",0.017453292519943295]],
PROJECTION["Albers_Conic_Equal_Area"],
PARAMETER["False_Easting",0],
PARAMETER["False_Northing",0],
PARAMETER["longitude_of_center",25],
PARAMETER["Standard_Parallel_1",20],
PARAMETER["Standard_Parallel_2",-23],
PARAMETER["latitude_of_center",0],
UNIT["Meter",1],
AUTHORITY["EPSG","102022"]]
3) WKT for ESRI 102022 at https://epsg.io/102022
PROJCS["Africa_Albers_Equal_Area_Conic",
GEOGCS["WGS 84",
DATUM["WGS_1984",
SPHEROID["WGS 84",6378137,298.257223563,
AUTHORITY["EPSG","7030"]],
AUTHORITY["EPSG","6326"]],
PRIMEM["Greenwich",0,
AUTHORITY["EPSG","8901"]],
UNIT["degree",0.0174532925199433,
AUTHORITY["EPSG","9122"]],
AUTHORITY["EPSG","4326"]],
PROJECTION["Albers_Conic_Equal_Area"],
PARAMETER["latitude_of_center",0],
PARAMETER["longitude_of_center",25],
PARAMETER["standard_parallel_1",20],
PARAMETER["standard_parallel_2",-23],
PARAMETER["false_easting",0],
PARAMETER["false_northing",0],
UNIT["metre",1,
AUTHORITY["EPSG","9001"]],
AXIS["Easting",EAST],
AXIS["Northing",NORTH],
AUTHORITY["ESRI","102022"]]
Note that the projection parameters are all the same (but with slightly
different naming conventions), but the CRS AUTHORITY line does not exist in the
GDAL version, is EPSG 102022 in the spatialreference.org version, and is ESRI
102022 in the epsg.io version.
Is it best to represent the CRS with WKT rather than importing using
SetFromUserInput with EPSG:code or ESRI:code? If so, what source has the
definitive WKT, spatialreference.org or epsg.io?
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