  We propose a novel method called the Relevance Subject Machine (RSM) to solve
the person re-identification (re-id) problem. RSM falls under the category of
Bayesian sparse recovery algorithms and uses the sparse representation of the
input video under a pre-defined dictionary to identify the subject in the
video. Our approach focuses on the multi-shot re-id problem, which is the
prevalent problem in many video analytics applications. RSM captures the
essence of the multi-shot re-id problem by constraining the support of the
sparse codes for each input video frame to be the same. Our proposed approach
is also robust enough to deal with time varying outliers and occlusions by
introducing a sparse, non-stationary noise term in the model error. We provide
a novel Variational Bayesian based inference procedure along with an intuitive
interpretation of the proposed update rules. We evaluate our approach over
several commonly used re-id datasets and show superior performance over current
state-of-the-art algorithms. Specifically, for ILIDS-VID, a recent large scale
re-id dataset, RSM shows significant improvement over all published approaches,
achieving an 11.5% (absolute) improvement in rank 1 accuracy over the closest
competing algorithm considered.
