Converting azimuthal map to equirectangular
Hi there. I've tried looking around for info on how to do this but am coming up blank.
I've got a map of a continent that is about 120° wide and 60° tall. It's drawn, basically, is if the world is flat. So let's say this is the equivalent, more or less, of the picture being taken from a satellite above the planet at a sufficient distance for the globe to look like a disc, and this satellite is positioned exactly over the center of this continent. So basically, this is a continent which will fit fine into an Azimuthal Equidistant projection using G.Projector, with the settings of longitude 0° E, latitude -30° N, and Radius 45°, with fill corners checked.
I want to take this azimuthal equidistant projection and project it back to a baseline Equirectangular projection. There doesn't seem to be any way in G.Projector to do this: it will only calculate other projections starting with an equirectangular projection, and won't go the other way around if you don't have an equirectangular one to start out with.
Any ideas? I'm open to ANY method that will get me from a "looks like a globe photographed from space" to an equirectangular map. The rest of the non-continent globe surface can be completely white, that's fine.