HI again

A picture is worth a thousand words so here you go

if any of you can visit this page :

http://movies.groups.yahoo.com/group/phil2film/

you will see an old screenshot of an old vegas version , hopefully the same technique will apply the the newest one.

Now you can clearly see that the parent track is a mask created from the guy you see jumping around , here is my question:

How can one go from the guy to the mask of the guy as seen in the middle of the picture where you have 3 shots of the 3 track stacked on top of the other.

Hopefully that's clear enough

thanks guys