This is probably an easy thing to do, but I'm new to After Effects and so I'm lost. Please feel free to answer the question in detail like I'm dumb, because I am!!!
Here's the situation: I have a video of a face, talking. It's blacked out all around the face so just the face shows, floating in blackness. Here's what I want to do:
1. I want to add a green background behind the face.
2. I'd like the background to be just slightly bigger than the face, but circular and show only a bit from behind the face around the edges.
3. And it'd be cool if the green circular background was moving (wavy).
This is probably easy to do if I only knew AE better. If it helps, I have a green circle made in Photoshop that I can use. But how do I get it behind the face, and make it appear to move or be wavy?
I appreciate any help, and like I said, feel free to be as elementary as need be since I am new to AE (I know Premiere Pro pretty well though).
Thank you sincerely in advance!
You need layers. You have to separate the face from the background. The easiest way would be a procedural matte using the luminance values, but this may cause a lot of problems if you have any black in the face. The pupils of the eyes, the hair, shadows, can all cause problems when you try to use luminance values to create a matte. Another option is rotoscoping, or drawing a mask around the face to eliminate the background. AE's rotobrush may work well for this if there is sufficient differences between the face and the background. If you can upload a screenshot of the face I can some techniques for either using luminance values to set up a matte or tell you if rotobrush will work. I can't tell without a screenshot. I'll also need to know if the face moves in the frame. If the shot is completely stable then a simple mask may do the trick.
Once you have the face cut out you can layer the other layers below the face layer and perform your magic.