1. Occlusion Tracking Using Logical Models Summary

2. A Variational Partial Differential Equations based model is used for tracking objects under occlusions and in complex backgrounds. Two assumptions are needed to successfully detect and segment the object: -Availability of prior shaped -Affine movement. The two possible logic models ( Energy=Image/Shape ) to segment the object with different instances are: -And logic model - Intersection ( ) -Or logic model- Union ( )

3. The segmentation energy is of the form:

4. The correct logical model combination depends on the occlusion's intensity relative to the object. (and) similar intensity(or)dissimilar intensity The correct logic model is the one which minimizes the quantity.

5. The general algorithm: Active contour ( ), affine transformation (g) and current frame (f) are used to generate an initial guess for the current frame. Compute and g via gradient descent on the AND/OR energy with initial data. Choose the minimum, using.

6. The limitations are: No explicit motion model, Sensitive to local minima when the quality of the image is low. Does not work with total occlusions. Computationally expensive. If motion is too great the sequential segmentation does not work.