Closed-circuit television (CCTV) has become popular in homes, schools, warehouses, sporting events, and various places. These systems have improved state surveillance and helped to reduce the crime rate. As of 2016, there were 350 surveillance cameras around the world with 65% of them installed in Asia. But what is CCTV and how does it work?
What is CCTV?
Closed-circuit television (CCTV) is a video surveillance system that uses video cameras to transmit a signal to a specific place or set of monitors. The signal is not transmitted publicly for security reasons, which is why CCTV differs from broadcast television. Also, these systems do not receive publicly broadcasted content but footage transmitted from cameras installed within premises.
What’s more, CCTV enables you to view what’s happening live and it can store its feed in a hard disk to be accessed at a later time. CCTV systems can operate continuously or based on how long they are needed to monitor events. There are advanced CCTVs, for instance, and these ones employ digital video recorders (DVRs). DVRs enable the system to record for several years. It also offers extra features to the system such as motion detection and email alerts.
How Do CCTVs Work?
There are different types of CCTV and while they all monitor the state of events, these devices are quite unique in how they operate. Some CCTV cameras are:
1. Analog Cameras:
Analogue cameras are the most common types of CCTVs and they have been used for some years now. These cameras come with basic features and help to store video onsite.
2. IP (Internet protocol) Cameras:
IP cameras offer enhanced functionality over analogue cameras. These cameras enable you to view the camera’s footage remotely using a smartphone, computer, or web browser. Therefore, you are alerted when a presence is detected in your home or business premises. IP cameras also have a better image capturing capabilities that makes the images they produce sharper and brighter.
3. Wired Security Cameras:
These cameras rely on cables to transmit their footage and conduct video surveillance. However, the signal gets weaken with an increase in transmission distance especially when it exceeds 300 meters. This problem can be averted with the use of the right networking cables, signal boosters, and switches.
Terms Associated with CCTVS
You’ll find the following terms used when describing CCTVs, they include:
1. Display Unit:
The DVR or NVR must be connected to a display unit such as a TV or monitor to view the camera’s footage. Such as display unit can have a simple monochrome screen or HD screen.
2. Structured Cabling Services
CCTVs whether wired or wireless rely on cables. These cables help to link the different types of equipment that will aid in video recording. The equipment includes monitors, modems, recorded, and wired cameras.
3. Video Recorders
CCTVs can capture events that occur during the day and at night, and as such, its storage might get full easily. And that means previous data may be wiped to input a new one. However, it is possible to program these cameras to record at certain intervals of the day, or generally, when motion or sound is detected. DVR and NVR are some video recording options.
a. Digital Video Recorders (DVRs)
Digital video recorders (DVRs) are the modern versions of analogue recorders that rely on videotapes. These cameras capture footage from an analogue camera in digital format. The capturing is also carried out using the desired resolution and frames per second. Further, new images are recorded over the oldest footage first once the storage is full.
b. Network Video Recorders (NVRs):
NVRs have a mode of operation similar to DVRs, however, they are used with IP cameras. Video cameras and NVR connect using the network switch or router. And the feed of the NVR can be accessed using a smartphone or web browser.
What is CCTV Used for?
There are several uses of CCTV in the real world and some of these include:
1. To Monitor Commercial and Residential Buildings:
CCTV is used in stores, banks, offices, and even homes to monitor the state of things and enhance the level of security of these premises. In homes, for instance, they can monitor the exterior in case an intruder walks in. Inline with that, CCTV equipment can be used in industrial plants to monitor the performance of parts in the central control room. These cameras ensure that processes are still monitored in the plant especially in areas that the temperature is not conducive for humans.
2. Traffic Monitoring:
Several cities around the world employ extensive traffic-monitoring systems that use CCTV to detect accidents and track congestion. For instance, these cameras can be placed at boundaries of and inside the congestion charge zone and the license plates of a driver are captured if they bypass the boundary. Cars that have been reported to missing are also traced using video footage from the cameras.
3. Sporting Events:
The reaction of fans at sporting events can be captured by installing CCTV cameras in the venue. Here, the cameras transfer the feed to a central control centre and the operator makes a choice on the feed that is to be sent to the television monitors. The selection is what is fans view.
CCTVs have become an active part of our lives since they keep us informed of what is happening within and outside our premises. They help law officials to solve crimes, bring criminals to justice, and at the same time, ensure that citizens adhere to regulations. Therefore, CCTVs are useful to individuals, companies, governmental organizations worldwide.