CCTV is a surveillance system that uses video cameras to monitor events in an area. These events can be monitored live either locally or remotely and can also be recorded and stored for future reference.
It is different from broadcast television in that the signal is transmitted in a closed, though it may employ point to point (P2P), point to multipoint, or mesh wireless links. It is often used for surveillance in areas that may need monitoring such as casinos, airports, banks, military installations, and convenience stores. It is also an important tool for distance education.
In industrial plants, CCTV equipment may be used to observe parts of a process from a central control room, for example when the environment is not suitable for humans. CCTV systems may operate continuously or only as required to monitor a particular event.
Advanced form of CCTV, utilizing 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). More recently, decentralized IP-based CCTV cameras, some equipped with megapixel sensors, support recording directly to network-attached storage devices, or internal flash for completely stand-alone operation.
Exactly how useful are CCTV Systems?
CCTV Systems are used basically for three main purposes:
• Crime Deterrence
• Crime Prosecution
• Live events surveillance & monitoring
Basic Types of CCTV Systems
There are three basic types of CCTV Systems:
• Analogue CCTV Systems
• Digital CCTV Systems
• IP CCTV Systems
Components of CCTV Systems
• Video Signal Acquisition – Cameras
• Video Signal Processing / Recording – Multiplexer / Switcher / DVR
• Video Signal Monitoring – Monitor / Television
• Signal Cables & Connectors – Cat 5 & VGA Cables / BNC Connectors
Video Signal Acquisition – Cameras
Cameras receive video signals of the surveillance area via its lens, and can be either wired or wireless.
Classes and Specifications of CCTV Cameras
• Dome Cameras – Class
• Bullet Cameras – Class
• Covert Cameras – Class
• Board Cameras – Class
• Vandal Resistant Cameras- Specification
• PTZ (pan, tilt, zoom) – Specification
• Night Vision – Specification
Video Signal Processing / Recording
• Switcher
• Multiplexer
• DVR
Video Signal Monitoring
• Monitor
• Television
