anyone willing to elaborate this:
1. Since you said ‘photographed’ I assume you have still images, so use PhotoShop to cut out the still images of the heads.
2. Import the head image into AE.
3. Use Motion Tracking to generate keyframes for following the heads in the original movie.
4. Use this data to make the photo heads follow the motion track.
5. Use keyframes for scale, position and rotation to orientate/size the new head to match the old one. May need to make new > old to avoid edge artifacts.
? thanks