Live is in 4.5 Unlimited. I think it's somthing to do with camera tracking in real video footage. [anyone, correct me if i'm wrong]
You're right it's used to track camera data from live footage (normally little crosses or ping pong balls) in scenes. Basically they allow you to see how the camera is moving so you can match your virtual camera up.
It's also in Maya 4.0 unlimited cause we have it at uni
Alan
Technical Director - Framestore
Currently working on: Your Highness
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