Adobe After Effects Forum
Zoomed In + Tracked Video Inset
Zoomed In + Tracked Video Inset
by Zach Spilinek on Jun 23, 2019 at 12:05:15 am

Hey there,

I'm trying something that seems like it would be really simple, but I can't figure it out.

I have a drone video that's an overview of a city, and some small dots (people) moving around. What I want is to have a video in the corner of the full frame (maybe 25% the size) that's simply a zoomed-in portion of the full size video, but also tracked and stabilized.

I couldn't find a video example so here's an image example: https://imgur.com/MOdGWEK

Imagine that its drone footage slowly flying over the crowd. I want the zoomed-in portion on the bottom-right to track on whatever object I choose (like the white trucks).

How can I go about this in After Effects? I do NOT need to do 3D tracking. X and Y tracking without scaling is just fine.

Thanks a million!


Re: Zoomed In + Tracked Video Inset
by Doyle Lewis on Jun 24, 2019 at 12:40:48 pm

Hello Zach,

This is actually pretty simple once you know how to do it.

To start you need to bring your footage in a new comp and duplicate it so you have 2 copies. Then add a null layer on top. Select the top copy of your footage and the null object and pre-compose it. Open up the pre-comp and right click the footage and choose Track motion. For this all you need is a single tracker, so leave rotation and scale unchecked, since neither is super important for what you want, you just want the camera to stick to the object. place your tracker on the object you want to follow and in the tracker options choose edit target. Change the target to the null object. Then let the tracker track through the footage through all the frames where your object is visible, correcting the track as necessary. Once it is all tracked to your satisfaction (remember it doesn't have to be perfect, just close enough. Too much micro-tweaking and your footage will be jumpy) then hit apply. This will put your track data to the null.

You will now see the little red box from the null follows your object around the scene. Now what we want to do is move the footage frame the exact opposite of the way your object moves so that your object remains stationary in the composition frame. To achieve this we will alt+click the stopwatch of the position of the footage and put in this expression
[640-thisComp.layer("Null 1").transform.position[0],359-thisComp.layer("Null 1").transform.position[1]]
If you renamed your null you will have to change or pickwhip the null part of the expression. Your footage will now jump somewhere around the screen, depending on where your object is it may even jump off the screen. to fix this you will need to use the pan-behind tool and grab the anchorpoint of your footage and move it around until the object you tracked is somewhere near the center of the composition frame. When you play the footage now you will see that the object remains in the center of the comp frame as the footage moves around in the frame to keep it there.

The last step is to get your picture in picture set up. So go to your outside composition and take the pre-comp you made and scale it up to have your object the size you want it in the frame. Then draw a mask around it in such a way that the frame edge doesn't ever cut into the mask, you will probably have to just watch it and trail and error it a bit until it looks good all the way through the shot. Then place your new box in whatever corner or part of the screen looks best. If you want to add a border you can drop the generate stroke effect on top of it and choose a color and line thickness to create your border.

Hope that helps

Doyle Lewis,
Assistant Location Manager
Warner Brother Pictures








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