plugin or method to remove black background

Hi all - 

I've been using the "outlines 2" plugin with FCPX (it may be a motion thing, I don't remember and I'm not too video savvy) to create clips and videos like this:



I'd like to remove the black background and be able to superimpose clips like this on top of other backgrounds.  I don't believe there's a way in the outlines 2 plugin to output the white lines only with a clear background.  It seems to be either the black background or the original clip as a background.  

So, is there a way to remove the black background from clips like these?  

Thanks!
Geoff

So, is there a way to remove the black background from clips like these?

If you select the clip in the timeline and go the the Video Inspector, you can set the "Blend Mode" to basically strip out the black background and reveal the clip underneath, while still keeping the white lines. You have a choice of blend modes and you can choose the one that works the best. To strip out the black background but leave the white lines, choose one of these:
Add, Lighten, Screen, Color Dodge, Linear Dodge

In my quick test, Linear Dodge was the cleanest. If you are familiar with Photoshop the Layer blend modes work in the same way.

That's perfect and exactly what I was looking for!

Thanks for the help