Need help with masking video for background video

Hi guys.

I'm new to Fusion 8.

I'm trying to mask out a part of a window in a video, to make another video appear in the masked area.
I want to achieve the effect of looking through a window and see something else.

Also, I would like to animate the mask, or make it follow the window frame with the help of some matchmoving technique.

How do I do that?

Hi Paul,

Welcome to the forum. Yours is a pretty common question. There are various topics on this forum that deal with it. Here's one for example:

viewtopic.php?f=22&t=56956

You can also find lots of helpful information in the manual. I don't know if you're wellversed in other compositing software packages, but if you're starting from scratch, the manual is a good place to start.