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In short, closed - Circuit Television (CCTV), is the use of video cameras to transmit a signal to a specific, limited number of monitors. It differs from the TV station because the signal will be publicly broadcast on public air waves. Usually a system of closed circuit television (CCTV) uses a stand-mounted or hand-held video camera to a larger picture on a monitor or television (TV), can be projected. CCTVSystems can continuously or only when needed to monitor a particular event.
The technology of video surveillance (CCTV) was created in 1950 and consists of two cameras at low resolution black and white. Its main objective was to replace the man for the visual control of security. In 1980, we introduced solid-state cameras and video. The resolution is better, but the images were in black and white. In 1990, he was the processingColor, and, finally, digital video recorders (DVRs) were introduced. Today, there are applications where the black and white cameras are used because they perform much better in low light conditions and application of lighting and infrared cameras in color. And cameras are smaller and smaller. Miniature security cameras today can be installed virtually anywhere (like cameras, infrared lighting, which allows us to be able to see in the dark).
Traditional video transmissionCCTV uses 75 ohm coaxial cable. The video signal is transmitted a composite video signal standard, although some systems use radio frequency signals. The camera is usually operated by low voltage (usually 12V or 24V powered) via a local power source near the camera or a separate power supply to the coaxial cable. There are also some systems that power the camera through the same coaxial cable, which is transported photo.
Some of the most popularApplications for video surveillance are:
Retail
- Monitor for shoplifters and dishonest employees
- Creation recorded evidence against false claims
- Control of merchandising displays in stores, hundreds of miles away
Builders, banks, casinos, hospitals and universities
- Identify visitors and employees
- Theft foiled
- Ensure the security of premises and car parks
Airports and militaryPlants
- Look for a possible high-Jackers and terrorists
Industrial Plant
- The procedures for monitoring, which are removed from a control room
- Monitor hazardous work areas
Sports
- Provision of fans in places of "cheap", a better view of what is happening.
Home Security
- Watch for unwanted visitors with video intercom doorbell
- Observation of child / guardian elders with a cam Nanny
In summary, advances in CCTV --Video surveillance using the technology in one of the most valuable loss prevention, security and management tools now available.
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