on Jun 22, 2014 at 2:07:22 pm Last Edited By Bilal Zaman on Jun 22, 2014 at 2:09:34 pm
I am working on a short scene where a weird girl slits a guy's throat. In the actual shot, girl just moves a knife on his throat and I have to add a slit throat effect with all the blood gushing out and stuff.
I googled a gory throat cut and made a png in Photoshop. Then I got blood-gushing stock footage.
Then I placed the cut on the neck and moved it with it after tracking motion in the footage.
Please look at THIS screenshot.
Note: None of the blood is real.
The problem lies where camera closes-up and the guy is moving his head. The cut stays in the place but due to the close-up, the size and perspective of the cut should change.
I'd kick the production team in the rear for that. Honestly I'd tell them that it would be faster and cheaper to reshoot with practicals than to do this in AE.
With what you have about the best is to use some form of warping alongside 3D movement/rotation to match the picture. There are several effects, but puppet pinning would be my first thought. Going to be a whole lot of tedious keyframing. I hope the throat cut you have is super high resolution (actually see if its possible to get a still/video of the actor with a practical, it should mesh far better).