Understanding CCTV Surveillance Devices

Understanding CCTV Surveillance Devices 


Closed Circuit Television, better known by its abbreviation CCTV, is a concealed or closed video system where viewing of its output (videos) is limited to a definite group of individuals. CCTV surveillance devices are available for premises with different architectural plans. They may be fitted within a single building, a group of buildings, large university campuses, corporate offices, supermarkets and malls. Monitoring of such areas is typically done for security and safety reasons.


The optical images generated by a CCTV device can be viewed as an event occurs or is recorded for ‘after-the-fact’ review either on-site or at a different location. VHS videotapes, CDs, DVDs and other tapes or computer based devices enable reviewing of the visual images recorded by CCTV. Review of pre-recorded images and sequences is also feasible with the use of telephone lines, fibre optics, the Internet and a range of other transmission methods. Such systems help to review CCTV footages remotely. The use of such systems for review depends upon the design and complexity of concerned CCTV system.


As a visual surveillance technology, CCTV was devised to simultaneously monitor a variety of environments and activities.  CCTV systems usually have a dedicated communications link between cameras in the concerned area and monitors at one or more control centres. While the older systems were made using analogue cameras and image storing machines, the modern systems use digital cameras and sophisticated storage devices. Some CCTV systems still use a combination of conventional and modern technologies.


Offering real-time or digitally recorded surveillance data CCTV set-ups effectively assist in detecting, reacting to, inspecting and providing evidence for security, safety and related incidents. Businesses and law & order personnel use advanced CCTV systems to avert security threats and incidents of theft, larceny, vandalism and corporate espionage.


Working of CCTV systems


CCTV system typically involves a linked set-up of cameras, the output of which can be viewed and operated from a series of control rooms and/or a central point of operation.


These cameras are available in multiple configurations, but may be categorised under two general groups: stationary and moving.


Stationary cameras are pointed at a particular scene of interest, such as an entry door or corridor, and broadcast that one scene to the control site all the time. Security personnel may adjust stationary cameras as per specific lighting conditions of that scene.

Stationary cameras can be completely exposed, or hidden within any kind of enclosure designed to meet the specific requirements of that site.


Moving cameras, generally referred to as PTZ (Pan, Tilt, Zoom) permit the system operator to change the position of the device by a remote control. This helps to focus and follow a particular object of interest more closely. This is typically done by use of a joystick in the control centre offering sideways (pan), upside and downside (tilt) and zoom in and zoom out control.


PTZ devices can also be manipulated to mechanically focus on areas of interest, such as when a door opens up or when movement is sensed


Since the camera can be aimed at scenes with varying lighting situations, these cameras characteristically have many programmed adjustments, such as auto focus and auto iris to keep the image optimized for accurate viewing.


Other sophisticated CCTV systems incorporate technologies with features such as multiple recording of many cameras, in different locations. At times CCTV is also employed to capture images for a facial recognition biometric system.


Located in Melbourne, Computer Cabling Services offers safe, secure and cost effective CCTV installations at residential as well as commercial premises across North, South, East and West Melbourne.


To know more about CCTV installation services in Melbourne suburbs or for a free quote, Call Computer Cabling Services on 03 9874 2166 or send your enquiry to