Automated visual surveillance systems

Visual surveillance for indoor environments, such as metro stations, plays an important role both in the assurance of safety conditions for the public and in the management of the transport network. The use of computer vision algorithms, which detect adverse situations such as accidents, violence or vandalism, at an early stage are expected to make these environments safer.

Digital Economy

In most indoor places, where multitudes of commuters gather, such as the metro stations, public security requirements are mainly met through adequate surveillance systems. Most metro companies primarily rely on Closed Circuit TV (CCTV) systems, comprised of an extensive network of cameras, in order to make their installations safer and to protect passengers and equipment. However, a CCTV system, typically deploying a large number of cameras, requires a respective availability of human operators to manage it. Since only a few of the available cameras can be monitored at any one time, potential incidents may not be detected on time. What it is more, a CCTV network is a rather reactive means of surveillance than a proactive one, since an incident may be monitored but often its outcome can not be prevented. Recent advances in computer vision techniques applied to CCTV, create promising prospects for an intelligent surveillance system. ADVISOR is such an automated visual surveillance system for metro stations, which was developed as part of the project ADVISOR (Annotated Digital Video for Intelligent Surveillance and Optimised Retrieval). ADVISOR allows the analysis of both real-time and recorded video feeds from surveillance cameras and generates alerts of unusual behaviour or dangerous conditions. The detection of an anomalous situation is based on behaviour recognition algorithms and it is displayed to a human operator within a short time. ADVISOR, through an ergonomic human computer interface (HCI), offers a wide range of possibilities to the surveillance operators such as the quick retrieval of annotated video frames. The HCI also provides the operator with a means to define alarm conditions, set-up additional cameras, combine current and previously recorded images or search interesting sequences into the archive. The system also allows the manual selection and simultaneous real time display of images from various cameras, reducing significantly the operators' workload. ADVISOR is a scalable, integrated unit with an HCI configurable to the site's needs and security policies. Test runs have shown that the system, if commercially exploited, it may help to provide a more secure environment in public places.