Installing a security camera system is one of the most cost-effective ways to safeguard your properties and discourage residential burglars. The live or recorded footage from these security cameras are of great benefit to help the local authorities track down the criminals and bring them to justice. In the meantime, the significance of surveillance in business cannot be overestimated in the current social climate where financial crimes are flourishing. The real-time video surveillance could lower security-related costs (cheaper than hiring round-the-clock security guards for strategic locations), resolve business disputes (hard evidence to reach a fair resolution), boost productivity within the workplace, and bring any kinds of reprehensible activities to a halt.
Video surveillance has always been a controversial topic looming over our heads when it comes to privacy issues, and thereby it is essential to know the regulations in your state or country before implementing the cameras because privacy violations caused by unauthorized or improper placements will eventually land you in court. But when properly applied, it is still a strong deterrent to avert potential crimes and protect your assets. A well-designed and efficient video surveillance system is composed of three parts: security cameras, monitor or display equipment and recording devices.
The security camera is a video/audio recording device that delivers 24/7 continuous real-time monitoring and transmits the audio and video signals to a recorder, either an NVR or DVR for later review. Security cameras are of great benefit when monitoring your home or business premises at greater distances. Compared with hiring a couple of security officers to safeguard the main entrances or high-risk/traffic areas, installing security cameras is a more cost-effective way to prevent break-ins and vandalism to create a safer living environment and workplace. In businesses of all sizes and from all industries, security cameras are more than a strong deterrent to put a stop to potential thefts or any ill-intentions (i.e. sexual harassment, verbal and physical violence), they are beneficial for monitoring the day-to-day activities to boost the productivity of employees while keeping a constant eye on dishonest employees.
In general, security cameras can be roughly categorized into three types: bullet cameras, dome cameras and Pan-Tilt-Zoom (PTZ) cameras. Long and cylindrical in shape, bullet cameras are probably the most traditional monitoring devices used in the surveillance system. They have a fixed or variable focal lens that is designed to target one specific location with a substantial viewing angle. Compared with other cameras, they are capable of housing larger lenses, which makes them ideal for coverage in large areas (i.e. parking lots, airports, traffic intersections) to provide higher levels of details. Additionally, its distinguishable appearance also serves as an effective visual deterrent to burglars and thieves. On the contrary, dome cameras are more low-profile encapsulated in an inverted dome casing. They can be attached to the ceiling or wall to offer a more discreet way of surveillance. Some dome cameras, albeit stationary, have a tinted encasing to prevent the intruders from knowing which direction the camera is pointing. And they’re vandal-proof as well. Last but not least, the PTZ cameras, as their name implies, are cameras that can pan side-to-side, tilt up and down and zoom in and zoom out via remote control to provide a comprehensive field of view (360°). They are high-resolution cameras with great scalability and flexibility. Equipped with infrared night vision with built-in LEDs, it can function normally in low-light settings.
2. Analog or IP Cameras
Analog cameras are the traditional cameras that transfer the recorded footage to a digital video recorder (DVR) through a coaxial cable and require separate wired connections for power supplies. One of the obvious reasons to stick with your analog system is the price tag. Analog cameras are always kept at a reasonable price range to meet the need of the average population. They show great resilience and durability in long-term use without frequent maintenance or replacement. Typically, analog cameras have a narrower field of view with lower resolution than their digital counterparts. Nevertheless, to ensure better footage quality, the cameras must be placed at a reasonable distance near the DVR, or the reliability will be compromised. They will suffer significant signal degradation and distortion in enlargements.
On the other hand, IP cameras send the footage over the Internet or LAN to a network video recorder (NVR) via a single Ethernet cable (CAT5e/6) for both power and data connections to eliminate unnecessary wiring and expensive installation costs. Greatly advanced, the IP-based cameras have a broader viewing angle with additional smart features such as motion detection, audio recording, object/human recognition. Compared with the analog cameras, the IP cameras have great versatility and flexibility on installations with a maximum deployment distance of 100m/328ft. For long-distance applications, please read PoE Extension Solution Explained and Applications to find the best extension methods. And the cameras allow for freely zooming in or out on an object without reducing the clarity. Encryption is also included in the IP technology to prevent hacking. The potential downside to the digital cameras is that they are more expensive (supporting equipment, i.e. PoE switch, is needed to run the system) than analog cameras. And they have higher bandwidth and storage requirements.
3. Wired or Wireless Cameras
Wired security cameras normally transfer the video footage through wired connections to the recording devices. As previously mentioned, analog cameras depend on the DVR for storage with a coaxial cable (separate wiring for power required), while the IP cameras rely on an Ethernet cable for both power and data transmission. The most advantageous aspect of the wired surveillance system mainly lies in its reliability, for it’s nearly impervious to signal degradation or any type of interference except the damages to cables or the cameras. And in some advanced surveillance systems, if the burglars try to disconnect the cameras by cutting off the cables, the alert system will be automatically activated to deter the unwelcome intruders. Additionally, it will not suffer image degradation caused by bandwidth fluctuations. But the wiring design also puts a damper on its applications in long-distance deployments. And professional installation might be necessary, which increases the costs of investment.
Most residential or business property owners will choose wireless security cameras to keep their premises under surveillance owing to their flexibility in placements. Wireless cameras collect and stream the data over the wireless network and store the data on a cloud server or PC software to enable people to view live or recorded videos on their smartphones or tablets. Compared with that of their wired counterparts, the installation of wireless cameras is less labor-intensive and more straightforward (no complicated wiring involved). And they are relatively cheaper with reduced costs in the initial investment (fewer cables and supporting devices required). Considering that the wireless cameras depend entirely on networks for data transmission, they are more susceptible to signal degradation and bandwidth fluctuations, suffering severe image degradation. And sometimes radio frequency interference (RFI) would occur. Worse still, they are more subject to hacking for the direct connection to the Internet.
Monitor or Display Equipment
The display units are the viewing screens where you can watch the live or recorded videos, working together with DVRs or NVRs, which can be connected to the TV or other HDMI-compatible devices through HDMI connectors. And the video feeds can also be accessed via computers and mobile phones, which offers great convenience to people who want to keep an eye on their properties while they’re away. And the cameras can be directly connected to the PC to eliminate complicated configurations. In businesses, a more professional display unit is adopted, which only allows authorized personnel to check the videos. Traditionally, security officers are required to watch the live feeds on the monitors 24/7. Nowadays, some systems can send instant notifications to the security staffs when the motion detection is triggered so as to set up a highly efficient monitoring system.
The recording devices used in the surveillance system are the digital video recorder (DVR) and the network video recorder (NVR), which capture the footage transmitted from the cameras and store the processed files for later review. The biggest difference between these two devices is how they process the data. And it’s important to note that the DVR is for the wired surveillance system, while the NVR is applicable to wired and wireless systems.
The DVR system processes the data at the recorder by converting the analog signals to digital signals. The cameras used in the DVR system must be analog cameras, and every camera should be connected directly to the recorder via a coaxial cable for signal conversion and data storage (point-to-point connection). Given that the coaxial cables are only designed to carry data, additional wiring is required for power supplies. As such, you’ll have to install the recorder near a power outlet. And the installment is more expensive because coaxial cables cost more than LAN cables. Since standard coaxial cables do not support audio so an extra RCA connection (an electrical connection for video and audio signal transmission) is needed for audio recording. The size and rigidity of these cables also pose great challenges to installation. Furthermore, the image quality will become to deteriorate after 90m/300ft, which highly limits its application in long-range deployments. Because of their limited capacities, the DVR system is more affordable than its counterpart, featuring simple and straightforward operations. Moreover, it shows high interoperability when it comes to mixing analog cameras of different brands, which saves you a large amount of money to replace cameras.
In the NVR system, the footage is processed at the camera where there is a built-in chipset to deal with the processing and transmits that stream to the recorder, while the recorder is only used for storing and viewing the footage. In this manner, the NVR will only suffer less signal distortion and image degradation during data transmission. And it features high-resolution image quality with improved functionalities like remote control and dual-monitor display (HDMI & VGA). Compared with its counterpart, the NVR only works with digital signals, so the majority of NVRs are used together with the IP cameras through a single Ethernet cable for both data (video and audio signals) and power transmission, thus eliminating the need for additional wiring. Compared with the coaxial cables, the Ethernet cables are easier to handle thanks to the simple plug-and-play design. Moreover, the NVR is inherently more convenient because the cameras don’t necessarily have to be connected to the recorder. Instead, they only need to work on the same wireless network. However, it’s relatively more expensive than the comparable DVR system. And since not all cameras are compatible with all NVR systems, you’ll have to buy the cameras and recorder from the same manufacturers to make a perfect match. Additionally, the NVR system will suffer signal loss in overloaded networks.
For more information, check FASTCABLING to create a hazard-free living environment and workplace by setting up an efficient video surveillance system.