1. Markerless Motion capture frances le august 20, 2008 presented by

2. Goals for this project

3. » Identify major body parts. » Track them. » Update the state of the body at next frame. » Pass the state to Carley.

4. What do all these limbs have in common?

5. » In 2D, the lengths and widths of a limb are constant. » A joint can be found a certain distance from another joint on the same limb in any given frame. » Certain joints such as the shoulder or the middle of the spine do not move very much.

6. Finding Major body parts

7. how i find the bird » look for the highest leftmost point. » find the vector tangent to the body contour curve at that point. » identify the vector perpendicular to that tangent vector. » discover the point (which is generally near the elbow) that best fits the line represented by the perpendicular vector. (and the elbow)

8. » find the point closest to first elbow point found. other elbow points

9. other elbow points » find the point closest to last elbow point found starting from the tip of the hand going counter-clockwise.

10. » find the point closest to second elbow point found starting from the last elbow point going counter-clockwise. other elbow points

11. finding limb info » for each point counter-clockwise from the tip of the hand, we find a point perpendicular to its tangent.

12. » for each point counter-clockwise from the tip of the hand, we find a point perpendicular to its tangent. » both the distance between the two points and their median coordinates are stored. finding limb info

13. » for each point counter-clockwise from the tip of the hand, we find a point perpendicular to its tangent. » both the distance between the two points and their median coordinates are stored. finding limb info

14. » for each point counter-clockwise from the tip of the hand, we find a point perpendicular to its tangent. » both the distance between the two points and their median coordinates are stored. » in addition, we find the vector that best fits the middle points. finding limb info

15. » for each point counter-clockwise from the tip of the hand, we find a point perpendicular to its tangent. » both the distance between the two points and their median coordinates are stored. » in addition, we find the vector that best fits the middle points. » we do this for both the forearm and the upper arm. finding limb info

16. finding joint info » we keep the location of the joint. » we also keep the angle.

17. Problems unsolved

18. the upside down arm » range of cos -1 function requires us to know something about the orientation of the arm. » animation needs to know orientation of the arm.

19. we have gaps

20. Fin (for now)