2 frames in 1?

[jellysandwich]

Let's say I wanted to make a video of size 400*600.
The top 400*300 would be video clip A, while the
bottom 400*300 would be video clip B.

How might I do that?

-jellysandwich

[Guest]

StackVertical(a,b)

[jellysandwich]

Thanks.

-jellysandwich