Sensor Fusion for Cooperative Head Localization

In modern video surveillance systems, pan-tilt-zoom (PTZ) cameras certainly have the potential to allow the coverage of wide areas with a much smaller number of sensors, compared to the common approach of fixed camera networks. This paper describes a general framework that aims at exploiting the capabilities of modern PTZ cameras in order to acquire high resolution images of body parts, such as the head, from the observation of pedestrians moving in a wide outdoor area. The framework allows to organize the sensors in a network with arbitrary topology, and to establish pairwise master-slave relationship between them. In this way a slave camera can be steered to acquire imagery of a target keeping into account both target and zooming uncertainties. Experiments show good performance in localizing target's head, independently from the zooming factor of the slave camera.