1. Motion Capture Technology

3. Introduction
• Motion capture is the process of recording human
movement through specialised camera’s, and
mapping them onto a character model .
• Motion capture technology involves sensing,
digitizing, and recording that object in motion.
• It is also known as Mo-Cap, Virtual Theatre, Real-
Time Animation or Performance Animation.

4. The birth of motion capture
 Historically, Motion Capture
in animated movies was
created using the
extension of
"ROTOSCOPING" technique.

5. Rotoscoping
A Rotoscoping is a device that enables animators to
trace live action movement, frame by frame, for use
in animation.

6. Rotoscoping
Captured Video:
Rotoscoping works by first
capturing a video of a real
actor around props that
resembles elements of a scene.

7. Rotoscoping
Tracing:
Animators then trace over
each frame of the recorded
video, this would result in a
figure that moved in a
very realistic fashion.

8. Rotoscoping
Post Processing:
Finally, the animated figured
would be coloured and then
integrated with various
background layers to create
the final shot.

9. The MOCAP Pipeline
Calibration
Capture
Fitting to the Skeleton
Post Processing

10. Calibration
C 1
C 2
Triangulation C 1
= (x , y , z )
1 1
= (x , y , z )
1
principle!!!! C 2 2 2 2

11. MOCAP Techniques
There are three MOCAP techniques:
1) Optical
2)Magnetic
3)Mechanical

12. Optical

13. Optical
Infra Red
cameras

14. Marker Placements
Location should move rigidly
with joints
Stay away from bulging muscles

15. Multiple Hypothesis Tracking
C1
C2

16. Magnetic
Magnetic Transmitter

17. Mechanical
Potentiometers

18. Fitting to the Skeleton
Utopian approach
 10 – 20% length
changes
Markers on both
sides
Joint Displacement
θ
Use Rotation Angles
Only

19. Post Processing
Motion Editing
 Cut, Copy, Paste
Motion Warping
 Speed up or Slow Down
 Rotate, Scale or Translate
Motion Signal Processing
 Smoother Motions

20. Applications
Entertainment
Medicine
Arts / Education
Science / Engineering

21. Entertainment: Live Action Films
Computer generated characters in live action films.

22. Entertainment: 3D computer animations
Characters in computer animated files (e.g.
Avatar, Polar Express, Monster House)

23. Entertainment: Video Games
Video games by Electronic Arts, Gremlin, id, RARE,
Square, Konami, Namco, and others, (e.g. Enemy
Territory)

24. Games using Motion Capture

25. Medicine
Medicine (e.g., gait analysis, rehabilitation)
Sports medicine (e.g. injury prevention,
performance analyses, performance
enhancement)
Gait Analysis Service

26. Science / Engineering
Engineering (e.g., Biped robot developments)
Military (e.g., field exercises, virtual
instructors, and role-playing games)

27. The Future of MOCAP
• Markerless MOCAP
• Cheaper MOCAP
• MOCAP as Input to Large Displays
Bregler et al., 2002

28. Conclusion
Motion capture (MOCAP) is an
effective 3D animation tool for
realistically capturing human
motion.