Re-identifying people in the wild

People re-identification in uncontrolled scenarios is a difficult task since people appearance may significantly vary along time due to changes in illumination, changes in the person pose or the presence of undesired objects in the scene. In order to cope with this temporal variability in the person appearance, we introduce the concept of Bags of Appearances (BoA) to describe each person. A BoA is a container of color features that fully represents a person by collecting all their different appearances along time. Matching of bags is performed in a probabilistic framework by accumulating the probability of matching for all of the elements of each bag. Experiments have been conducted in a real shop where clients were re-identified at the entrance and exit. Results improve state-of-the art methods and confirm that our proposal successfully copes with rough changes in the people appearance.