ĬCTV control-room monitor wall for 176 open-street cameras in 2017.Īn early mechanical CCTV system was developed in June 1927 by Russian physicist Léon Theremin (cf.
The deployment of this technology has facilitated significant growth in state surveillance, a substantial rise in the methods of advanced social monitoring and control, and a host of crime prevention measures throughout the world. The growth of CCTV has been slowing in recent years. About 65% of these cameras are installed in Asia. More recently, decentralized IP cameras, perhaps equipped with megapixel sensors, support recording directly to network-attached storage devices, or internal flash for completely stand-alone operation.īy one estimate, there will be approximately 1 billion surveillance cameras in use worldwide by 2021. A more advanced form of CCTV, using digital video recorders (DVRs), provides recording for possibly many years, with a variety of quality and performance options and extra features (such as motion detection and email alerts). CCTV systems may operate continuously or only as required to monitor a particular event. For example, when the environment is not suitable for humans. In industrial plants, CCTV equipment may be used to observe parts of a process from a central control room. Video surveillance has generated significant debate about balancing its use with individuals' right to privacy even when in public. In recent years, the use of body worn video cameras has been introduced as a new form of surveillance, often used in law enforcement, with cameras located on a police officer's chest or head. Surveillance of the public using CCTV is common in many areas around the world.
Even though almost all video cameras fit this definition, the term is most often applied to those used for surveillance in areas that require additional security or ongoing monitoring ( Videotelephony is seldom called "CCTV" ). It differs from broadcast television in that the signal is not openly transmitted, though it may employ point-to-point (P2P), point-to-multipoint (P2MP), or mesh wired or wireless links. Dome camera in a railway station: Rotterdam central metro stationĬlosed-circuit television ( CCTV), also known as video surveillance, is the use of video cameras to transmit a signal to a specific place, on a limited set of monitors.