Rotobrush to MASKS

I am also trying to do this, and the reason is an obnoxious shortcut oriented workaround, but this is what software is supposed to do—make things that we used to do by hand on film efficient in video.

I converted my video to extremely high contrast to get the rotoscope to better stick to the edges of my subject. Now I want to use that information to create a mask over the properly color balanced clip of the subject. Yes, this is a workaround to avoid frame-by-frame work, because this is what software is for! So I got the idea to export the entire video as png frames and create an automation task in photoshop and then convert the frames to black and alpha, then import png frames back into a video file for import into after effects to mask my very flat color-balanced video.

So if it is that easy for me to achieve a workaround using an automated recorded action in photoshop why in the heck isn't this a function in after effects?

I know this post is quite old now, but I have found a great workaround to create a mask from a rotoscope. However, this will only apply to a single frame.

1. Rotoscope a single frame in the layer view and freeze the frames before exiting to composition view.
   • The only visible part of the layer remaining should be the selected portions of your rotoscoped area.
2. With that layer highlighted, go to the layer tab in the menu and select "Autotrace" to create a mask around the rotoscoped area.
3. Copy the mask from the newly created shape layer to your rotoscoped layer.

If you combine this with @todd_kopriva you should be able to use this to animate your mask. I have not tried this myself though.

What it says in the Help document is this: "You can copy Roto Brush Path properties, and paste them into masks, shapes, and instances of the Paint effect, just like you can with other kinds of paths." That refers to the fact that you can copy the Roto Brush strokes' paths and paste them into mask path properties. However, I'm guessing that that's not what you're actually trying to do. I'm guessing that what you actually want is to take the transparency information that the Roto Brush effect creates as a matte and convert that to a mask that defines the same transparency information. To do that, you could use the Auto-trace command. The masks created by Auto-trace aren't usually what you want for conventional mask-animation rotoscoping work, though. So, the question is this: What are you trying to accomplish?

Thanks for the information guys! I will try to have a little more patience with the RotoBrush and mess around with the settings.

What it says in the Help document is this:

"You can copy Roto Brush Path properties, and paste them into masks, shapes, and instances of the Paint effect, just like you can with other kinds of paths."

That refers to the fact that you can copy the Roto Brush strokes' paths and paste them into mask path properties.

However, I'm guessing that that's not what you're actually trying to do. I'm guessing that what you actually want is to take the transparency information that the Roto Brush effect creates as a matte and convert that to a mask that defines the same transparency information. To do that, you could use the Auto-trace command. The masks created by Auto-trace aren't usually what you want for conventional mask-animation rotoscoping work, though.

So, the question is this: What are you trying to accomplish?