We present an approach for tracking varying number of objects through both temporally and spatially significant occlusions. Our method builds on the idea of object permanence to reason about occlusion. To this end, tracking is performed at both the region level and the object level. At the region level, a customized Genetic Algorithm is used to search for optimal region tracks. This limits the scope of object trajectories. At the object level, each object is located based on adaptive appearance models, spatial distributions and inter-occlusion relationships. The proposed architecture is capable of tracking objects even in the presence of long periods of full occlusions. We demonstrate the viability of this approach by experimenting on several videos of a user interacting with a variety of objects on a desktop.
(size: 10M! need MPeg4 codec to play the video)
Yan Huang, Irfan Essa
Tracking Multiple Object through Occlusions. CVPR 2005, Jun, San Diego, CA. [pdf]