Apply tracking data to masks?

Here are two scripts that do what you want:

http://forums.creativecow.net/readpost/2/916999

Tracker2Mask is a free script of mine that does the job and is really easy to use.
Usage is explained in the video tutorials here:
http://aextensions.blogspot.com/2009/02/tracker2mask.html

Morgan, that's what i tried first, but you cannot set Mask position in AE. Only its shape. If I duplicate the layer and parent it to the null, the whole layer moves and the masked region moves all over the place...

[Jimmy Brunger] "I'd love to be able to apply different trackers to diff points on a mask...would that be a script-based command or is it not possible in AE?"

This is exactly why I wrote the Connect_Vertex_to_Point script, which is at the top of my scripts page:

http://www.crgreen.com/aescripts

With my script, you do one vertex (mask point) at a time.

Hi Jiri,

Try adding your levels to an adjustment layer and drawing the mask onto that. Then track the footage, add the track data to a null, and parent the adjustment layer to the null. I think this works...

Simon

Wow, James, way to knock the ball out of the park with that answer.

That was EXACTLY the correct way to do what the original questioner was looking for. For animating the mask on a non-transforming object inside a scene - basically keeping a tight roto around an object that isn't moving - James's explanation above is THE way to do it.

A great way to highlight an object in a scene.
A great way to blur a single object in a scene.
A great way to color correct an object, like a chair, in a scene.

So many uses. No need for scripts (because the original mask isn't changing that much, just transforming along x and y.) Thanks James for setting it out step-by-like that.

Robert N.

I was following along and he brushed over a step. But, I'm not going to repeat how it was explained. Instead, I'll explain what you'll have as a final result:

One precompiled composition with three layers (in order, top to bottom):

1) A solid color. The actual color doesn't matter. The point of this layer is to contain one or more masks. The way in which is follows the movement is by setting the parent of this layer to the layer with the transform moves. Note: You could apply the tracking (transform) info to this layer, instead of using a parent, but you don't really want to do that because you won't be able to use transform for anything other than this layer.

2) The parent null object "Tracking" layer. This layer doesn't even need to be visible. It's just here to provide instruction to the top layer. After applying the tracked motion to this layer the first layer (including the mask) will move, trench, rotate.

3) Your image that will be within the mask (#1). You don't have to apply any effects to this layer, as it will probably be better/easier to apply the effects in your original composition.

You will also have your original composition, prior to making the precompiled comp. Your original composition will contain (top to bottom):

1) The precompiled composition.

2) The background / outer masks/layer(s). Basically, everything else.

Apply your adjustments to #1, above.