It would probably be hard, but think about it this way.

If they can detect and record brain waves in present day science, then if somebody had the money and the manpower in the future, we could probably research how a brain "interprets" them during it's dream time (i.e. how a brain also sees hypnagogic images, and fully clear pictures in one's head) , and then construction of a facility that interprets brain waves into video and audio images can occur.

Anybody have any thoughts on this subject? I obviously don't have all the bases covered, but I guess it makes good conversation