user8029: when using magic bullet looks on a video it applies - alongside color corrections and such - a frame, some sort of wrapping mask thingy - a black outline for the video the gives the center a bit more focus. You can see it pretty clearly here:

I want a png of that. Just that. I am searching Google for all kinds of word combinations but nothing. What is this effect called??

user4426: it's a vignette.
Here's a tutorial on how to do it.
If you add a black solid layer to a comp, then feather the edges, and invert the mask, you'll get the basic effect.  Beyond that, some people used coloured solids (e.g. just off-black in one colour or another).  You can also apply a blur or defocus effect towards the edges of the image, if that's the look you're going for.

8029: <p>when using <a href="http://www.redgiant.com/products/all/magic-bullet-looks/" rel="nofollow noreferrer">magic bullet looks</a> on a video it applies - alongside color corrections and such - a frame, some sort of wrapping mask thingy - a black outline for the video the gives the center a bit more focus. You can see it pretty clearly here:</p>

<p><img src="https://i.stack.imgur.com/rEX0z.jpg" alt="enter image description here"></p>

<p>I want a png of that. Just that. I am searching Google for all kinds of word combinations but nothing. <strong>What is this effect called??</strong></p>
 4426: <p>it's a <a href="https://en.wikipedia.org/wiki/Vignetting" rel="nofollow">vignette</a>.
Here's a <a href="https://www.youtube.com/watch?v=yHdJoUxJfyk" rel="nofollow">tutorial</a> on how to do it.</p>

<p>If you add a black solid layer to a comp, then feather the edges, and invert the mask, you'll get the basic effect.  Beyond that, some people used coloured solids (e.g. just off-black in one colour or another).  You can also apply a blur or defocus effect towards the edges of the image, if that's the look you're going for.</p>
