[SOLVED] CS CSCI 520 Computer Animation and Simulation

CSCI 520 Computer Animation and Simulation
Motion Capture
Jernej Barbic
University of Southern California
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What is Motion Capture?
Motioncaptureistheprocessoftrackingreal- life motion in 3D and recording it for use in any number of applications.
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Why Motion Capture?
Keyframes are generated by instruments measuring a human performer they do not need to be set manually
The details of human motion such as style, mood, and shifts of weight are reproduced with little effort
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Mocap Technologies: Optical
Multiple high-resolution, high-speed cameras
Light bounced from camera off of reflective markers
High quality data
Markers placeable anywhere
Lots of work to extract joint angles
Occlusion
Which marker is which? (correspondence problem)
120-240 Hz @ 1Megapixel
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Facial Motion Capture
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Mocap Technologies: Electromagnetic
Sensors give both position and orientation
No occlusion or correspondence problem
Little post-processing
Limited accuracy
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Mocap Technologies: Exoskeleton
Really Fast (~500Hz)
No occlusion or correspondence problem
Little error
Movement restricted
Fixed sensors
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Motion Capture
Whynot?
Difficult for non-human characters
Can you move like a hamster / duck / eagle ? Can you capture a hamsters motion?
Actors needed
Which is more economical:
Paying an animator to place keys Hiring a Martial Arts Expert
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When to use Motion Capture?
Complicatedcharactermotion
Where uncomplicated ends and complicated begins is up to question
A walk cycle is often more easily done by hand
A Flying Monkey Kick might be worth the overhead of mocap
Cananactorbetterexpresscharacter personality than the animator?
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