Abstract.
Filtering based algorithms have become popular in tracking human body pose. Such algorithms can su?er the curse of dimensionality due to the high dimensionality of the pose state space; therefore, efforts have been dedicated to either smart sampling or reducing the dimension- ality of the original pose state space. In this paper, a novel formulation that employs a dimensionality reduced state space for multi-hypothesis tracking is proposed. During off-line training, a mixture of factor analyz- ers is learned. Each factor analyzer can be thought of as a “local dimen- sionality reducer” that locally approximates the pose manifold. Global coordination between local factor analyzers is achieved by learning a set of linear mixture functions that enforces agreement between local factor analyzers. The formulation allows easy bidirectional mapping between the original body pose space and the low-dimensional space. During on- line tracking, the clusters of factor analyzers are utilized in a multiple hypothesis tracking algorithm. Experiments demonstrate that the pro- posed algorithm tracks 3D body pose efficiently and accurately , even when self-occlusion, motion blur and large limb movements occur. Quan- titative comparisons show that the formulation produces more accurate 3D pose estimates over time than those that can be obtained via a num- ber of previously-proposed particle filtering based tracking algorithms.