No. An OpenStreetMapper has come up with his own rather less sophisticated pipeline for doing this sort of work:

http://wiki.openstreetmap.org/wiki/User:Balrog/Aerial_Imager...

but it's a way off what this software seems to be able to do.

There's not much magic in what Pix4D does - the algorithms are generally well documented (though tricky to get to work well from what I understand), it's just no-one's done it yet.