Dynamically overlaying a face (external JPG) to a video

I have short 10-20sec. video(s) of a girl dancing. I need a system that would allow users to dynamically upload and overlay their own faces in place of the girl's face. And I need it to look as good as possible - as realistic as possible. This would mean the following probably: - the user would first upload a photo of him-/herself - the user would then select her/his own face on the uploaded photo (probably with an easy ellipsoid tool or possibly by marking distinctive features on the photo - like nose, chin, forehead, ears, eyes, etc.) - then I need a realistic method of overlaying that face instead of the girl's face in the video (watch out - the face in the video is obviously moving and turning so the uploaded face needs to mimic those movements as best as it can) This might be done via bump mapping and/or point tracking of distinctive facial elements on the photo and the video (nose, ears, chin, forehead...) This is NOT an animation project!!! This is a programming project and only people with real expert actionscript experience need apply! A novice or an intermediate would not do - but an actionscript expert could probably make this in a day or two only. We unfortunately have a very limited budget! And its urgent. Please quote me your price, time needed and describe how you would handle this problem + give me examples of your previous work.