Where Digital Worlds Meet the Real World: From Chroma Key to Motion Capture

1. Do you believe whatever you see in the movies? Here's how to portray the D-Day landings with 3 people and a green screen...

So how did that work? Green screen/chroma key techniques allow part of the image to be masked out and then replaced with a different image playing within that mask

(and what's so special about GREEN anyway...?)

Motion Capture (or mo cap) is the process of capturing human or animal movements in such a way that they can be used to animate “digital actors”

By placing markers on and close to skeletal joints, it is possible to capture which bits of the skeleton move – and how – whenever a particular action is performed

...and it's not just for capturing human movements...

So how does motion capture work for games?

Having to use markers to capture the movements adds a significant overhead to the process of motion capture, (it can be a fiddly job locating the markers).

Using markers also limits what data is actually captured... ...so ideally, we'd like a markerless system

Why? Because markerless motion capture can be used to capture tiny facial movements, as well as full body movements

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