Compositing and masks

[Susanna]

Hi Steve,
I've been reading through your book and trying out various things, but got stuck on the section in Chapter 7 - Parent and Composite your video tracks (p.117), under the sub-heading: Mask a composite video.

...on the Video Overlay 2 track, I have placed a Generated Media clip of a white circle with a transparent background.

Try as I might, I cannot find this mask - I looked under Video FX and Media Generators and managed to make something that worked by playing about with Color Gradient - Elliptical Transparent to Black, but really didn't know what I was doing!
Also, on the facing page, you say

If I switch the Compositing Mode of Video Overlay 1 to Multiply (Mask), as illustrated on the right...

- but the illustration on the right shows Multiply Mask on Video Overlay 2?
I did get this to work, but is there an easier way to make a mask?
Thanks!

[Steve Grisetti]

Yes. You can also make a mask using the technique described in the next section, Blur a Face as on TV's COPS.

It basically does the same thing: Shows a small area of the video on the upper video track and shows whatever is on the video track below (if any) around it.

As I say in the book, parenting and compositing tracks if pretty advanced stuff.