Converts a PROJJSON CRS string into a WKT CRS string (WKT1 or WKT2:2019 variants supported). Warning: while the export to WKT1 should be syntaxically correct, datum, projection method or parameter names will be the one of WKT2, and thus a number of implementations will in practice fail to understand such WKT1 strings.
This library is a single file with no dependency, that could be easily ported to other languages. The following languages are available:
- Python (this repository)
- JavaScript
Currently supported object types are: GeodeticCRS, GeographicCRS, ProjectedCRS, VerticalCRS, CompoundCRS, DerivedGeodeticCRS and DerivedGeographicCRS.
usage: projjson_to_wkt.py [-h] [--format {WKT2:2019,WKT1}] [--single-line] projjson
$ ./projjson_to_wkt.py '{"$schema":"https://proj.org/schemas/v0.4/projjson.schema.json","type":"CompoundCRS","name":"WGS 84 + EGM96 height","components":[{"type":"GeographicCRS","name":"WGS 84","datum_ensemble":{"name":"World Geodetic System 1984 ensemble","members":[{"name":"World Geodetic System 1984 (Transit)","id":{"authority":"EPSG","code":1166}},{"name":"World Geodetic System 1984 (G730)","id":{"authority":"EPSG","code":1152}},{"name":"World Geodetic System 1984 (G873)","id":{"authority":"EPSG","code":1153}},{"name":"World Geodetic System 1984 (G1150)","id":{"authority":"EPSG","code":1154}},{"name":"World Geodetic System 1984 (G1674)","id":{"authority":"EPSG","code":1155}},{"name":"World Geodetic System 1984 (G1762)","id":{"authority":"EPSG","code":1156}},{"name":"World Geodetic System 1984 (G2139)","id":{"authority":"EPSG","code":1309}}],"ellipsoid":{"name":"WGS 84","semi_major_axis":6378137,"inverse_flattening":298.257223563},"accuracy":"2.0","id":{"authority":"EPSG","code":6326}},"coordinate_system":{"subtype":"ellipsoidal","axis":[{"name":"Geodetic latitude","abbreviation":"Lat","direction":"north","unit":"degree"},{"name":"Geodetic longitude","abbreviation":"Lon","direction":"east","unit":"degree"}]}},{"type":"VerticalCRS","name":"EGM96 height","datum":{"type":"VerticalReferenceFrame","name":"EGM96 geoid"},"coordinate_system":{"subtype":"vertical","axis":[{"name":"Gravity-related height","abbreviation":"H","direction":"up","unit":"metre"}]}}],"scope":"Spatial referencing.","area":"World.","bbox":{"south_latitude":-90,"west_longitude":-180,"north_latitude":90,"east_longitude":180},"id":{"authority":"EPSG","code":9707}}'
COMPOUNDCRS["WGS 84 + EGM96 height",
GEOGCRS["WGS 84",
ENSEMBLE["World Geodetic System 1984 ensemble",
MEMBER["World Geodetic System 1984 (Transit)",
ID["EPSG",1166]],
MEMBER["World Geodetic System 1984 (G730)",
ID["EPSG",1152]],
MEMBER["World Geodetic System 1984 (G873)",
ID["EPSG",1153]],
MEMBER["World Geodetic System 1984 (G1150)",
ID["EPSG",1154]],
MEMBER["World Geodetic System 1984 (G1674)",
ID["EPSG",1155]],
MEMBER["World Geodetic System 1984 (G1762)",
ID["EPSG",1156]],
MEMBER["World Geodetic System 1984 (G2139)",
ID["EPSG",1309]],
ELLIPSOID["WGS 84",6378137,298.257223563,
LENGTHUNIT["metre",1]],
ENSEMBLEACCURACY[2.0],
ID["EPSG",6326]],
CS[ellipsoidal,2],
AXIS["geodetic latitude (Lat)",north,
ANGLEUNIT["degree",0.0174532925199433]],
AXIS["geodetic longitude (Lon)",east,
ANGLEUNIT["degree",0.0174532925199433]]],
VERTCRS["EGM96 height",
VDATUM["EGM96 geoid"],
CS[vertical,1],
AXIS["gravity-related height (H)",up,
LENGTHUNIT["metre",1]]],
USAGE[
SCOPE["Spatial referencing."],
AREA["World."],
BBOX[-90,-180,90,180]],
ID["EPSG",9707]]import projjson_to_wkt
json = {
"$schema": "https://proj.org/schemas/v0.4/projjson.schema.json",
"type": "CompoundCRS",
"name": "WGS 84 + EGM96 height",
"components": [
{
"type": "GeographicCRS",
"name": "WGS 84",
"datum_ensemble": {
"name": "World Geodetic System 1984 ensemble",
"members": [
{
"name": "World Geodetic System 1984 (Transit)",
"id": {
"authority": "EPSG",
"code": 1166
}
},
{
"name": "World Geodetic System 1984 (G730)",
"id": {
"authority": "EPSG",
"code": 1152
}
},
{
"name": "World Geodetic System 1984 (G873)",
"id": {
"authority": "EPSG",
"code": 1153
}
},
{
"name": "World Geodetic System 1984 (G1150)",
"id": {
"authority": "EPSG",
"code": 1154
}
},
{
"name": "World Geodetic System 1984 (G1674)",
"id": {
"authority": "EPSG",
"code": 1155
}
},
{
"name": "World Geodetic System 1984 (G1762)",
"id": {
"authority": "EPSG",
"code": 1156
}
},
{
"name": "World Geodetic System 1984 (G2139)",
"id": {
"authority": "EPSG",
"code": 1309
}
}
],
"ellipsoid": {
"name": "WGS 84",
"semi_major_axis": 6378137,
"inverse_flattening": 298.257223563
},
"accuracy": "2.0",
"id": {
"authority": "EPSG",
"code": 6326
}
},
"coordinate_system": {
"subtype": "ellipsoidal",
"axis": [
{
"name": "Geodetic latitude",
"abbreviation": "Lat",
"direction": "north",
"unit": "degree"
},
{
"name": "Geodetic longitude",
"abbreviation": "Lon",
"direction": "east",
"unit": "degree"
}
]
}
},
{
"type": "VerticalCRS",
"name": "EGM96 height",
"datum": {
"type": "VerticalReferenceFrame",
"name": "EGM96 geoid"
},
"coordinate_system": {
"subtype": "vertical",
"axis": [
{
"name": "Gravity-related height",
"abbreviation": "H",
"direction": "up",
"unit": "metre"
}
]
}
}
],
"scope": "Spatial referencing.",
"area": "World.",
"bbox": {
"south_latitude": -90,
"west_longitude": -180,
"north_latitude": 90,
"east_longitude": 180
},
"id": {
"authority": "EPSG",
"code": 9707
}
}
options=projjson_to_wkt.Options(
format = projjson_to_wkt.WKT1, single_line=True)
wkt = projjson_to_wkt.to_wkt(json, options=options)MIT