I am trying to define some of my local TMAF grids in PROJ.4 so I can reproject points between the local grid and MGA95 and/or WGS84.

For these grids I have the MapInfo CoordSys clause which defines a lot of parameters.
eg: “CoordSys Earth Projection”, 8, 33, 7, 117, 0, 0.9996, 500000, 10000000, 7, 0.890953, -0.455062, 2903977.24, 0.455063, 0.890954, -6919253.68, -100000, -100000, 100000, 100000

From the MapInfo doco I can see these parameters align to Datum, Origin Latitude, Scale at Origin, False Easting/Northing, and the Coefficients for the Affine Process.

What I'm having trouble with is trying to find out how to use these coefficients when creating a new custom projection, and the parameters in the PROJ.4 string that they could correctly map to.

1 Answer 1


According to someone on the PROJ.4 mailing list, they are fairly sure that PROJ.4 does not support the Affine post-process.

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