Installing video cameras
Conventionally it’s possible to divide the problem into two parts. The first one relates directly to the DVR unit. Modern cameras have gone far ahead from the alarming reports on a trivial signal loss and eventually progressed to image analysis. Nowadays video surveillance system can bring you not only the fact that the signal from the camera is stable, but also whether it is biased, out of focus, painted over with paint or sabotaged in one way or another.
The second part, clearly, refers to the cameras. Correct selection of the installation site, type of the camera, optics and compliance of all the components to the problem will help to significantly reduce the risk of “blinding” of the system. Do not install the camera so that it can be easily knocked down or damaged. Wide Dynamic Range (WDR) will assist in a case of compound lighting of the surveillance area – half of the image will not be marred or, conversely, over-obscured.
Reasonable choice of camera position is very important, since it largely defines the effectiveness of CCTV systems. With a clear understanding of what exactly should be protected (following an analysis of the object), it is possible, for example, to set at some points dummy cameras with stopping effect for violators. Actual devices at the same time can be disguised, making it difficult to analyze the object with the purpose of planning home Invasion by intruders. From my own experience I can say that we have often used dummy cameras in retail and storage facilities, but once in two months the dummies were rearranged to other places, and replaced by working cameras – it helped to fight with unscrupulous staff members. Another thing worth mention is a necessity of quality power supply for the cameras, which is especially important in case of a street location, since a voltage drop on the cable might become an actual problem.
When using IP-cameras there might be another advantage – many of them have a slot for Flash memory, and only a couple of extra hundred rubles for the on-board SD-card will save you in times when communication with the registrar will be lost for some reason. 4-8 GB of IP-camera built-in memory is enough to save high-resolution video lasting from a couple of hours to a couple of days.
And, of course, don’t forget to “eat properly”: the entire system must be uninterrupted. When designing and installing IP-based system it is imperative to use uninterruptible power supply (APC).
Choosing a network
Choose the IP-Surveillance – this will allow you to get rid of several redundant wires. For instance, in a hotel complex “Izmailovo”, 40 km of coaxial cable have been replaced with 1 km of fiber optic and 600 m of twisted pair (UTP5E).
Certainly, IP cameras have their own nuances and requirements, but in our times it is easier to find a network specialist than a decent CCTV adjuster. In addition, due to its characteristics digital networks are more protected from interference, easily expandable and upgradeable. Even higher investment in infrastructure is now easily repaid over time. With a probability of 80%, in the future you will continue to expand or rebuild your system to the IP.
The most versatile option – is to use IP system, which, coupled with the running of the cable magazine, labeled data lines and documented topology allows you to easily and quickly find the location of a breakdown or failure and diagnose the entire system, in most cases with the help of remote access.
Subtleties of Video Camera selection
This could be an endless conversation – it’s much easier to “blind” the camera than vice versa.
Areas of application for video surveillance are wide enough, and each of them has its subtleties. For example, face recognition systems require steady illumination, large number of pixels in the picture frame and surely color. For plate recognition systems, on the contrary, you’ll need video cameras with high resolution, but in black and white mode. Supervision of technological processes has unique requirements and in each field, so they will be different as well.
The simplest thing is to install the camera in the office or shop with constant and normal illumination. But with any other conditions you are going to face different kinds of problems.
Generally speaking, there are specific mistakes committed in this case. They are caused by the fact that the parameters of the camera and the illumination on the subject are not taken into account.
Such a phenomenon as the solar illumination of the camera lens is no longer a problem – the installers have learned to define regular camera direction subject to the movement of the sun. In order to install video cameras against the window they now use cameras with high dynamic range.
Several questions arise quite often: why the cameras begin to distort the color in dim artificial light? Why the black suit has become light-colored? Why there is “snow” on the camera image? The reason is that the camera does not meet the requirements of the site.
Another common problem is the way CCTV cameras operate in the night time. Owners of cameras with IR illumination want to receive a picture as clear as day. None of them takes into account such factors as the power of the IR illuminator, as well as the presence or absence of the IR filter in the camera.
There is another trend – chasing for high sensitivity of video cameras: it is believed that at nighttime it will be able to show a clear picture. Let us consider the behavior of the camera with a sensitivity of 0.00001 lux in the night mode in different cases. At night outside the city, in the moonlight, when the camera is switched to the night mode, free form external light sources the camera shows a picture as clear as day, and this seems to be the solution to all problems. But if you place the same camera in a city, in the middle of a busy street with good lighting, it will start to show rather turbid picture with great flare. This does not mean that the problem cannot be eliminated, but each case requires individual approach. It’s much easier to “blind” the camera than vice versa.
Reliable DVR functionality
With no doubt DVR is the core of video surveillance systems, you can monitor images centrally from all the cameras in real time, securely store and conveniently browse archive recording. When choosing a DVR you should pay attention to such fundamental characteristics as performance and reliability. High performance will connect the number of cameras transmitting high-definition video, and reliability is needed not only for a backup storage, but also for a stable uptime.
There should also be functional, providing convenient video archive search, compatibility with lots of IP-based camera models from different manufacturers and supporting users’ right of access.
Any technical security system, including video surveillance, requires not only qualified service, but also the necessary operating skills of the staff. In fact, it is a tool, and only security staff is responsible for its effective operation.
According to the results of a famous study, in 15 minutes of continuous monitoring the operator’s work efficiency is reduced by half, preventing him from quick reaction to various situations. To a certain extent this problem can be solved by technical means – by use of the video analysis.
In this case intelligent cameras or software programs conduct a primary image processing and according to certain parameters attract the operator’s attention to the screen. In addition, it is necessary to pay attention to the ergonomics of the operator’s working place, the logic of camera grouping on the screen in the situation center. Security trainings with certain required reactions to information received from camera system will be a perfect experience. This will secure the maximum efficiency from the use of video surveillance systems.
Nowadays you don’t have to talk about the maintenance of video surveillance systems, as rare customer prefers spending their money on this article of expenses.
Possibilities for system expansion
Over time, the structure of protected object may undergo certain changes. Commissioning of new areas as well as opening of the new facilities leads to a serious extension of the object. Having provided possibility of expansion of the video surveillance system in advance, you can avoid unpleasant surprises requiring complete or partial replacement of equipment. In this regard, it is worth paying attention to the ease of adding some cameras, whether you’ll need to pay for extra licenses, will it be possible to expand the storage tanks, will it be convenient to copy the archive to external network storage, or it is better to use cloud CCTV (VSaaS).
For IP system the expansion issue is solved much easier: we can connect additional cameras to the existing network hardware, if the switches there have some extra storage space. If not, a switch can be easily replaced by another. However, this is easy on the condition that network bandwidth allows such extension. Therefore, when building a network for IP-surveillance, it is necessary to consider their capacity of expansion.
In this case, we’re back to the cable networks: if under their construction the cheapest cable was used it is no need to talk about their expansion. You can change the active equipment on renew the operating one at high speeds, but if the cable is designed for lower throughput, it will not work.