CCTV - closed-circuit television systems
The closed circuit television systems (CCTV) lets the user monitor in real time suspicious events and persons and makes video records that can be viewed later.
CCTV systems include the following components:
- Video cameras
- Video multiplexation tools (switchers, multiplexers)
- Videotaping devices
- Viewing devices (monitors).
Video cameras can be divided into several categories (according to several criteria):
- visible or hidden
- Indoor or outdoor
- fixed or mobile (pan&tilt / speed dome)
- coloured or black and white.
- visible spectrum or infrared.
Video multiplexing tools can be analogical or digital (digital multiplexers or video capture cards). Digital multiplexers can also make records in a compressed format (mpeg4).
Video recording tools can be analogical or digital (on tape, in general) or digital (the record is saved on a hard-disk).