What is CCTV?
CCTV stands for closed-circuit television and is commonly known as video surveillance. “Closed-circuit” means broadcasts are usually transmitted to a limited (closed) number of monitors, unlike “regular” TV, which is broadcast to the public at large. CCTV networks are commonly used to detect and deter criminal activities, and record traffic infractions, but they have other uses.
CCTV technology was first developed in 1942 by German scientists to monitor the launch of V2 rockets. It was later used by American scientists during the testing of the atomic bomb.
So how does a modern CCTV system work?
The answer depends on the type of system involved. The systems are best defined by the types of cameras used. There are two common types of cameras in use today: Analog and IP-based cameras.
CCTV systems that use analog cameras have been around for years. They are still the most common type of camera installed in the field, experts say. Picture a camera or series of cameras with a dedicated set of wires fed into a recording device and series of monitors. Video is recorded and stored on site.
IP-based cameras carry out the same function as analog ones, but with a host of extra capabilities. IP cameras typically offer better images with higher resolution and more flexibility, allowing users to e-mail video images for consultation. In a large organization with many facilities, insurance companies often prefer, and in some cases demand, IP systems.
While many people use the term CCTV to refer to both IP and analog cameras, strictly speaking, the term should be limited to describing analog cameras.
Combined with powerful new software known as video analytics, an IP security camera can be programmed to “watch” for suspicious activity. A camera on an air intake, for example, can be programmed to display an alert and record video only when the space around the intake is disturbed.
IP cameras work by using an IP (IP stands for internet protocol) network, often the same data network the rest of a company uses. If bandwidth is a problem, a separate network using category 5 wiring can be used. Either way, video information is recorded on a server, which means video data can be located on site or in a remote location.
Though storing the vast amount of data can be a concern, it’s not unusual for IP CCTV systems to have software that governs how long the video is stored, and at what quality. After a time, video can be compressed to save storage space, for example.