How best motion-match face in two clips?
by Tom Clasman on Jan 10, 2017 at 7:58:15 am
I'm looking for the best (i.e. most expensive-looking) way to merge two film shots of the same face, in such a way that I can crossfade over from one shot to the other, virtually seamlessly. My video fx skill level I'd rank as a 3 or 4, and very new to After Effects as well.
I got a scene, good quality, which is filmed twice. Background and actor etc is fairly similar. But since it is two takes, the expression and position of the actor doesn't match 100%. I want to crossfade over from one clip to to the other, and I need to synchronize the face of the actor to give me enough time to create a crossfade - as opposed to a cut.
In the first clip, the actor's face is somewhat in the center, somewhat the same size.
In the second clip, the camera-guy is slowly panning the camera a bit sideways, and the zoom factor and angle is a little different from the first clip
During this panning, the position of the actor's face coincides to 85-90% in both clips at a short moment. That's where I want to make the crossfade.
I want to merge the actor's face, and make a crossfade between the clips, in such a way that it 'appears' to the eye as if the only changing is the background - if possible.
I've tried matching the actor's face in both clips, by sliding the second clip's entire location on the canvas and adjusting the zoom too (creating keyframes for both position and zoom for every single frame) in parallel with the first clip, all while making the crossfade. It kindof works, but since not all points in the face can be matched it turns out blurry and leaves you with a cheesy feeling.
Just before writing this I learned how to do motion tracking, even advanced facial tracking, in After Effects. I've just tried making advanced facial tracking on both clips and pick-whipped each facial element from one clip to the other. But After Effects doesn't seem to apply the effect at all. Maybe it thinks there is just too many differences to apply this method.
Also, I am not sure of to what extent I should use facial tracking vs adjusting the frame location&zoom. I suspect I may have to use both methods.
Or ... I might have some kind soul here telling me I'm way off track ☺
Re: How best motion-match face in two clips? by Blaise Douros on Jan 10, 2017 at 5:15:24 pm
George Lucas? Didn't you learn your lesson from Star Wars? 😉
How about using Morph Cut in Premiere Pro?
You might have to do some preparation before using this effect. For example, you may need to roto out the actor from Scene 2 onto the background of Scene 1, so that you can place him in a location that is as close as possible to Scene 1 so the background doesn't abruptly shift. Then render out Scene2_Comp, import to Premiere Pro, and use Morph Cut to blend them.