How to choose a camera for video surveillance

Video camera for video surveillance is an essential attribute of any modern protected object. The need for video recording of what is happening often helps in solving crimes, and also helps prevent them. Most of the modern office and municipal buildings of any city are equipped with such a video camera. It is rather difficult to argue with the demand for this category of equipment, but there are a number of features that must be taken into account when confronted with a camera for video surveillance. In the formats of surveillance cameras, there is a variety that allows you to choose the equipment that is suitable for a particular object as accurately as possible. Let us consider in more detail the main categories and understand the differences.

Differences between analog and digital video camera

Conventionally, the market for video cameras can be divided into two main groups: digital cameras and analog ones. Looking ahead, it should be noted that the main difference between the two types of technology is in the methods of signal transmission, as well as in its subsequent processing.

Analog Video Camera transmits video from the matrix in analog format for observation. The camera, receiving a signal, digitizes it. For further sending you will need to re-encode the data in analog format. Sometimes this type of signal is called composite (CVBS). Through a coaxial cable, the signal enters the display and a special recording device that digitizes, encodes and compresses it for further recording on the hard disk.

Analog RVi Camera

Digital video camera does not convert the signal back to analog to transmit it.In connection with this feature, the task is greatly simplified. The recording device receives a digital signal that has not passed through the recursion of transformations from analog to digital and vice versa.

Digital IP camera Orient IP-33-SH24APSD

Ahd camcorder

The first thing that distinguishes this format from others is it. is open. This is due to its popularity. Many camcorder manufacturers use this standard. Cameras of this type have and other benefits:

• You can achieve high-definition video recording at 720, 960 and 1080p;
• three signals of different types (image, sounds and instructions) are transmitted through one coaxial cable;
• transmission can be carried out at a decent distance - up to 500 meters from the source;
• AHD-camcorder does not require high-quality and expensive cable;
• There is no rigid binding to the recording device of one manufacturer.

The recording device is still necessary for operation, but another obvious advantage is its versatility. The AND-recorder is able to recognize the signal from a conventional, analog camera, as well as from an ip camera.

Transmission is carried out over twisted pair, using transceivers.Unfortunately, the weak point of this type of camera is level of remoteness from the source - it is only 150 meters.

Video camera Optimus AHD-H012.1 (2.8-12)

Ip camera

A modern video surveillance standard, which, unlike analog, transmits an image exclusively in digital mode, also encodes it. Instead of a coaxial cable, either twisted pair or fiber-optic wire is used. There is no link to the registering unit., therefore, the camera can be installed anywhere, as long as the wire reaches out.

IP-based wireless video camera is also not uncommon. IP-cameras with a Wi-Fi receiver are installed in many retail outlets where there is a need to disguise optics as much as possible.

Another advantage is high resolution image. Some models of the described standard have a resolution of up to 12 megapixels and support a full 4K. To such indicators analog equipment is still far away.

Anti-Vandal IP Camera RVi-IPC31

A significant plus is no power wire. From now on, the power is supplied directly over the twisted pair, which saves space when laying communications.This effect is achieved through POE technology for IP-based cameras. A significant drawback is the price: it is much higher than on analog models. In addition, IP cameras are more difficult to configure and integrate into an existing video surveillance system, especially if it is assembled under analog equipment.

HD TVI cameras

At the heart of HD TVI-camcorder is open technologywhich has won high popularity. This type of camera uses Dahua technology, which allows to achieve quite high definition from 720p to 1080p. As in most modern devices, three signals are transmitted over one coaxial cable at once: image, sound and operator commands. The main advantage is the absence of any image delays. Transmission can take place at a distance of up to 0.5 km. In addition, the technology itself allows the use of different recording units, and not just one manufacturer. It is possible to use a twisted pair and audio connectors, but in this case the signal transmission is reduced to 100 m. You can connect any other cameras except IP to the recording unit, which makes this format universal.

On a note! The most popular brand of HD TVI-format is the RVI brand.

Hybrid cameras

This is a format that even suits for tv. Hybrid camcorders are designed to unify different formats. Such devices have several video outputs of the most popular formats and are connected to various recording units. This feature makes them the most accessible for TV connection. Modern and reliable devices that differ from their competitors only by a large number of moves.

Differences between home and street cameras

Types of video cameras for video surveillance vary greatly. For example, some are more suitable for the home, while others can be used in outdoor environments. Home video cameras do not require a high degree of security, optical properties and insulated electrics. More requirements are put forward for equipment that will be operated on the street, because the indoor environment is not so aggressive; there are no strong temperature, humidity or heat fluctuations in the building. The main and significant difference between outdoor cameras and office cameras is the increased security of the first. The case of a conventional camera can be made of ordinary plastic, while the outdoor camera will be covered with a special rubberized coating and protected from moisture to certified standards. Special attention is paid to isolation wiring outdoor cameraswhile the models intended for the room do not require any additional protection for it.

For outdoor video cameras, in contrast to office and home options, there are higher requirements in the field of optics. In particular, it's about the glare. If indoors, especially at night, a beam of bright light does not greatly affect the operation of the device, then in open space at night, bright light may blind the device for some time, thereby disabling it. This weakness can take advantage of attackers, so you should pay attention to this factor in advance.

The more outdoor camera focus distance, especially the most distant objects will look larger, which is very useful when observing in the distance. In total there are three types of models for outdoor use: panoramic, portrait, and with an average approximation.

Building a video surveillance system requires an optimal ratio of all its components. The level of noise and signals is considered optimal if it does not exceed 50 dB (for open space). In the dark, the amount of noise increases significantly.

Glare protection possesses, as a rule, professional equipment. Most often, a special electronic locking mechanism that significantly reduces the exposure time, or an automatically controlled aperture, is responsible for protection. The latter simply narrows the hole through which the excess light passes. In cameras that are used indoors, this technology is practically not required.

Also cameras for streets can vary in design.

1. Dome Camera. This type of apparatus is specially protected from damage (explosion-proof). The body is made in the form of a hemisphere, and inside is a rotating optics. With the help of such cameras, you can get a panoramic (wide-angle) image and easily observe moving targets.
   

   Ergonomic SRD-TWDN700SDL Dome Camera

2. Cabinet. The most common type of cameras. Inexpensive, with good optics and good capabilities.A significant disadvantage is the need to install multiple cameras in one place.
   

   Samsung SCB-2002P Color Video Camera

3. PTZ cameras. A remote server manages such gadgets, which is very convenient for remote monitoring. Most often used on the street.
   

   Speed ​​dome HD camcorder SDMH522A

4. Modular camcorders. Quite a popular type, which is used both indoors and outdoors. The peculiarity is that such a camera can be assembled by yourself, based on your needs. You can design a camera with a microphone, wired or wireless. The modular camera does not have a case, only the motherboard and the lens are included, everything else is purchased independently.
   

   Modular AHD Video Camera MDC-AH2290FTN

CCTV Cameras

Mini surveillance cameras can be distinguished in a separate segment. These are portable video cameras and embedded in the prepared hole. Exist models with motion sensorwhich has flexible settings. Its sensitivity determines how accurately it will react to the movement of an object that is in its field of observation. Most often used in apartments.

Security Camera HRT-607 with Motion Sensor

If the model can interact with a flash drive, then this greatly expands its capabilities. Observation with writing to a memory card allows you to significantly increase the amount of memory, some models support flash cards up to 128 GB, but this is usually professional equipment. The larger the amount of flash drive supported by the camera, the more it can record material.

Standalone battery powered camcorders They do not need wiring, but their essential drawback is the short period of video recording. Most often, such hidden cameras are used in cases where observation is necessary for a short time.

Wireless Security Camera GW-0116415

Little ones camera enclosures they are good because they are easy to hide even in clothes, or simply put behind a small object (photo frame, etc.). The packageless model is the most compact, but its disadvantage is a small autonomy and poor video quality due to the small matrix.

Parameters for choosing a video camera for monitoring

Select a video camera for video surveillance is easy, but there are certain nuancesin which you need to understand to make a successful purchase. The first thing that needs to be understood is the place and circumstances of operation. The second item is the number of devices. For some needs, it is necessary to organize a whole network to get an objective picture that captures an object from all angles, in other cases a single device is enough.

For example, you can install a single camera to monitor a room or an entrance, and you need several cameras to view the corridor comprehensively.

Video camera sensitivity and light level

A very important parameter for the organization of round-the-clock monitoring of the object. Especially useful is the sensitivity parameter. for night surveillance. Night shooting can often cause problems due to a large amount of noise (noise). The higher the sensitivity parameter, the more it will be possible to consider in the dark, the dependence here is direct.

To date, most models come with a backlight. At a specified time, they automatically switch to monochrome. Such cameras are perfect for operation in day-night mode.

Photosensitivity is a parameter of the minimum value of illumination at which optics can see the perimeter.. This parameter is measured in a special unit - "luxury". For round-the-clock surveillance with night shooting, an option with a lux value of 0.01 is perfect.

Focus distance and viewing angles

This parameter is directly related to the functionality of a video surveillance camera, both analog and IP. Most often his can be adjusted or changedusing various nozzles. There are more drastic measures, for example, replacing the lens with the best optical performance. The focus distance and the viewing angle are responsible for the width of the area that is placed in the frame. Most low-end models are deprived of the possibility of adjusting the initially set settings.

It should be remembered that not all cases require a widescreen image. For example, for video surveillance of a small room, you can get by with an inexpensive model.

Image quality and resolution

One of the most important parameters. High-resolution camcorder is capable of delivering a clearer picture. The greater the resolution of the board and its physical parameters, the more accurate the picture will be written to the carrier. there is 4K resolution modelsbut there is not always a need for them.

Of course, it is worth striving for a higher matrix resolution, because the quality of the entire image as a whole depends on it. There is one pattern - a quality matrix is ​​difficult to place in a small case. You should not expect high quality portable devices, and mobility and mobility from expensive professional equipment.

Color or black and white

Color video camera allows you to transfer a more coherent and rich image. Monochrome cameras are more associated with night vision when you want to switch to black and white mode for greater clarity. Black and white picture more resistant to glare, while the advantage of color in greater clarity.Color video cameras are most often used for observation in large stores, since provide a more objective transfer of information, on the rollers, filmed on such a model, it is easier to establish individual signs of objects and objects.

The organization of video surveillance via the smartphone

Recently, a type of video camera is gaining popularity, with which you can monitor an object by contacting it with a smartphone. This requires the corresponding model with Internet access. Best of all, if it will be supported by GSM standard 3g.

A camera with a sim card constantly has a permanent connection to the Internet. For the organization of such video surveillance, in addition to the existing equipment, it is necessary purchase the appropriate softwareusing cloud technology. Communication with the subscriber occurs through the network storage provider. This is where all the information comes from the camera. After saving in the cloud, the picture can be transmitted to the phone with a little late (most cloud providers promise a minimum ping).

There may be problems with the image on the phone.This is a weak point of this technology. To prevent data transmission may, for example, a broken connection.

The organization of video surveillance through the online broadcast on the phone is as follows:

• • Installs a camera connected to the Internet (SIM card or Wi-Fi);
  • appropriate software is installed on the camera and phone;
  • registration on the cloud storage;

• launching a broadcast on the camera, setting up and synchronizing with the cloud;
• connect your smartphone to an active session in the cloud, sync.

This technology has a number of advantages: in particular, it allows the owner to observe an important object, even from a very long distance. The downside of technology is big internet connection. If the session is terminated, it’s far from the fact that after reconnecting the connection, the camera itself can launch a new session in automatic mode, you may need a manual correction. Another disadvantage is paid software. Software for deploying an online surveillance network is usually not distributed free of charge. And if such a program is found, it will be available only with significant limitations.As an option, a limited place in the cloud storage, which, as practice shows, ends very quickly and has to be re-purchased.

Conclusion

Monitor for setting up video cameras It is necessary to make a separate item. This is a test device, without which the work of any electrician can not do. With it, you can adjust the perimeter, as well as diagnose problems and monitor the construction of the network. An important attribute of anyone who, one way or another, is associated with the maintenance of the object by video surveillance.

As you can see, the organization of a network of video surveillance cameras requires some skill. Of course, today in the video equipment market there has been a tendency to massively lower prices for a number of models, but affordable price is not the only determining factor. In order to competently organize the observation of the object, it is important to clearly understand the final goals, and only then plan the budget. As in all other areas of the consumer market, the most expensive is not equivalent to the best.