1. Computer Graphics Lab Electrical Engineering, Technion, Israel June 2009 [1] [1] Xuemiao Xu, Animating Animal Motion From Still, Siggraph 2008

2. Create an animation movie by reconstructing the animal motion from a still picture Algorithm Still Image Animation Movie

3. Shape Context Descriptor Find distances Path Finding 6,3,4,1,2,5 Consistency Refinement TPS Morphing TPS Morphing Creating Animation snapshots Shape context descriptors Distances matrix Motion Path Consistent snapshots Animation between two snapshots Source Image Snapshot Extraction

4. Find the contour of the snapshot For every point on the contour draw the circles and bins as shown Create the “matrix descriptor “ Invariant to translation, rotation and scale.

5. Distance between Snapshot-K and Snapshot-L: Point on snapshot K Closest point on snapshot L How do we find ? Distance between two matrix descriptors

6. Find the optimal path between the snapshots using the distances matrix Energy function of path: Avoid “getting stuck” on a local minimum by using Simulated Annealing Optimization Algorithm, which allows us to “exit” a local minimum.

7. Full Cycle: Half Cycle:

8. Pivot In order to create smooth and realistic animation, all the animals have to be in the same pose relative to the camera. Affine transformation includes: Translation scale rotation All snapshots are translated relative to a pivot snapshot.

9. Pivot histogram: Every snapshot has its own color and texture that can vary from one snapshot to another. Histograms standardization of all snapshots will make the final animation look smoother.

10. Finding animation points: Points which are not static during the animal motion Morph between the source points and target points Source Image is registered to the green points Destination Image is registered to the red points.

11. Morph three frames between two snapshots Source Destination 0.75 0.25 0.5 0.750.25

12. Tadpoles: Turtles: