Hi I think it will be nice with two camera or if you are able to re-possision the camera , it is also an idea to have some point in the scene so you can refere the posision of that , anyway I don't know if the correction can be made that way, but a digitizer in AutoCAD can be callibrated --- that mean that if you pick a known point on the screen , -- that will be your picture on the screen and the digitizer working as digitizer mouse, -- then you can add several other known points callibrating your digitizer from the graphic on the screen.
Now if you can see where this is heading you could have found an ansver ,but this ask some efford and knowleage and ownership of a digitizer.