The RATP, i.e. the state-owned transport operator of Paris (France), has installed intelligent cameras in the parisian metro station of Châtelet to control the wearing of face masks. The initiative takes place in the post-lockdown period, when the mask is mandatory for the users of public transport in Paris.
The technology works with six cameras (to be increased to 12) disseminated in the metro station that record the commuters and use facial recognition to detect if they wear a mask. More specifically, the cameras are connected to computers that transform the images in data that is then treated through an algorithm determining if the person wears a mask or not. This process allows to count the people wearing a mask.
A crucial point is that the technology is not aimed at identifying and fining the offenders, but at measuring the evolution of the mask wearing day after day and providing statistics on the mask habits of the metro users. In this end, the data collected by the computers is only treated every 15 minutes. This time delay ensures the anonymity of the commuters and prevents the use of personnal data to other ends than general statistics.