Applying the Track Matte Effect to the Second Clip

We have our "hider" in place and tracking well with the baby's face. We've applied our Mosaic effect to the second undercoverbaby.avi clip in the Video 2 track. Now we need to hide everything in the Video 2 track except that small portion that we want to show through the ellipse which will thoroughly disguise the baby's face. To do that, we will apply the Track Matte effect to the clip in the Video 2 track and select the Video 3 track as the "target."

Apply the Track Matte Effect

Type track in the text box on the Effect and Transition panel to find the Track Matte effect in the list of effects.

Select the Track Matte effect and drag it onto the undercoverbaby.avi clip in the Video 2 track on the Timeline.

In the Properties panel for the undercoverbaby.avi clip on the Video 2 track, click the triangle next to Track Matte Key to reveal the effect's controls.

Set up the Track Matte Key:

• Matte: Video 3

• Composite Using: Matte Alpha

• Reverse: Leave unchecked

Did You Know?

You can browse through the list of effects to find the effect you're looking for. You could have navigated to this effect by selecting the triangle next to Video Effects in the Effects and Transitions panel to reveal the available effects. You would then click the Keying triangle to see the available keys, and then select the Track Matte Key. To make browsing easier, change the view (MORE, List View or Icon View) as suits your working style.