Hi! So, I'm subbing out part of a background and it's going really slow on my system. I'm only adding a few elements to the background (behind the people in the shot,) so I don't need the people to be completely extracted--if I mask out part of the layer, will rotobrush continue to calculate for the parts that are not showing?
A mask probably won't help. A nested comp in dimensions that cut the bottom of the shot off might.
But then, the phrase, "slow on my system" is pretty nebulous. We don't know anything about your hardware, OS, footage being used, or AE version. It's tough to know if its behavior really is slow or par for the course.
KGAN (CBS) & KFXA (Fox) Cedar Rapids, IA