CCTV cameras: a universal device for all spheres of life
It is difficult to imagine safety in all spheres of life in the modern world without video recording. CCTV cameras convert optical data into an electrical video signal, so that the picture can be seen on the monitor. The quality of the final image depends on the technical parameters of the device. You can learn about what types of cameras exist and how to choose the right equipment for monitoring from this article.
Installation CCTV cameras allows for round-the-clock control over the object
To improve the safety of human life in many areas, a video surveillance system is organized, which is represented by a set of technical means and software.
Outdoor cameras equipped with weather protection
The installation of CCTV cameras, the price of which depends on many criteria, allows for round-the-clock control over the territory or an individual object, which reduces the number of petty thefts, increases the safety of life, and allows you to display the chronology of events in the event of a situation at the facility. Devices are often installed in offices to monitor staff performance.
In case of controversial issues, you can view a certain time period on the video from CCTV cameras, which will allow you to resolve the contradictions. At enterprises, using video surveillance cameras, you can control the quality of work, the safety of property from theft.
Important! Thanks to the video surveillance system, it is possible to respond in time to an emergency, which will save human lives and the integrity of the equipment.
Cameras are often installed on the streets of cities, which makes it possible to ensure security, respect for the rights and freedoms of citizens, reduce the criminal situation, prevent terrorist threats, exercise control over city utilities and infrastructure, and prevent accidents and emergencies.
The video surveillance system will allow you to timely respond to emergencies at the facility
All information is recorded to hard disk or cloud. Some models compress the size of the incoming files, which significantly saves storage space. Cameras have various functionalities that allow you to adjust the brightness, image contrast, size and speed of moving objects. The devices are equipped with protection against weather changes. They can work at any time of the day. Night photography is provided using IR illumination.
Recording can be carried out continuously, according to an ongoing event, according to a set schedule, at the command of a motion detector. The archive is formed by the time and name of the event, which allows you to quickly find the required file, export it to a different format, and write it to external media.
Component elements of a modern video surveillance system
Any video surveillance system includes video cameras, quadrators, multiplexers, video recorders, video monitors and control panels for rotary tracking devices.
The video surveillance system consists of video cameras, quadrators, multiplexers, video recorders, video monitors and consoles
Cameras for video are presented in a wide variety of models, which differ in design, installation location, method of information transmission and other operational characteristics.
Multiplexers and quadrators carry out preliminary analysis and subsequent processing of information for transmission to monitors and recording devices. These devices are relevant for analog CCTV cameras. Using the quad, you can view information on the screen from four devices at the same time.
Important! Connection of the IP camera to the recorder is carried out without using this equipment.
Camcorders are presented in a wide range, they differ in design, installation location, data transfer method, price and other characteristics
A simplex multiplexer outputs images from all cameras, a duplex multiplexer simultaneously records video to the recorder. The triplex device, in addition to the above capabilities, allows you to view the previously recorded information.
To record data, digital, analog or hybrid video recorders are used, which are integrated into a computer and can perform video signal processing functions using PC resources. To display information, video monitors are used, on which the program for video surveillance cameras is installed.
Choosing a video recorder for video surveillance
The choice of the type of video recorder depends on the option of the video surveillance format, the level of image detail, the speed of information recording and other operational parameters.
The video recorder must be selected based on the type of cameras installed
The DVR is primarily selected based on the type of cameras installed. Depending on this, there are analog, digital and hybrid devices. The first option can be said to be a DVR equipment that records a video signal in digital format and connects to the camera via a coaxial cable. CCTV cameras are connected to a computer monitor using an HDMI cable. Such video recorders on the rear panel are additionally equipped with outputs for connecting microphones. Each channel must match the camera channel.
IP recorders work exclusively with digital cameras.NVR type devices support 1-12MP resolution. The rear panel of such devices is more primitive. It contains a network port and a connector for connecting to a monitor. There is no microphone output, since it connects directly to the CCTV camera. Hybrid models can interact with any cameras.
When choosing a recorder for video cameras, you should pay close attention to the recording resolution of the device. The higher this parameter, the better and more detailed the image will be.
Important! For high-resolution recording, you will need enough hard disk space, which will significantly increase the cost of installing video surveillance.
For high-quality and detailed images, you need a high-resolution video recorder
The next criterion is the recording rate, which determines the number of frames per second that the camera captures. The optimal value is 25 fps. Here it should be borne in mind that the higher the resolution, the lower the recording speed. The next parameter is the compression format. Modern models are equipped with the H.265 algorithm.
Useful advice! You should choose a DVR with a large number of video channels, which helps to expand the perspective of the system.
Video cameras for video surveillance: device classification
Existing video cameras for video surveillance can be classified according to the place of installation, image transmission method, data transmission format and color rendering, degree of protection and design.
Outdoor cameras can withstand temperature fluctuations from -40 to +50 ° С
Depending on the place of installation, the devices can be external or internal. Outdoor video cameras are housed in special housings or housings that protect them from adverse environmental influences and weather conditions. A certain temperature and humidity regime is maintained inside the case. Such devices are mainly equipped with infrared illumination and anti-vandal protection.
Important! High quality outdoor cameras are certified for dust and water resistance.
Outdoor outdoor surveillance cameras can withstand temperature fluctuations ranging from -40 to +50 ° C. There are options for hotter climates that have a higher price tag. Surveillance cameras are selected based on the sensitivity value. This parameter determines the likelihood of noise interference and image flare. The outdoor camera provides signal transmission over a long distance, while maintaining the quality at the proper level. Such devices can be cylindrical, domed, or rotary.
Video cameras for indoor surveillance are smaller and are made in a plastic case
Indoor cameras are installed indoors. They, in comparison with street options, are characterized by smaller dimensions, less reliable fastening and the lack of additional protection against adverse environmental influences. Such devices are presented in plastic cases.
Types of CCTV cameras by data transfer method
By the method of data transmission, there are wired and wireless video cameras for video surveillance. The first option is low cost and can be used for indoor and outdoor applications. The signal is transmitted via optical fiber, coaxial cable, or twisted pair. Fiber optic is used for wide area distribution networks. Signal transmission is carried out at a distance of up to 10 km with a frequency of 10 billion bit / s without the use of additional amplification. With the help of such a cable, a large amount of information data is transmitted.
Coaxial cable is the more expensive option. It is characterized by simplicity and reliability. It can be used without an additional amplifier.Signal transmission is carried out at a distance of no more than 400 m.
According to the data transmission method, video cameras for surveillance are divided into wired and wireless
The use of a twisted pair cable provides data transmission using special transmitters and receivers responsible for converting information. This cable is characterized by a high degree of protection. The signal spreads over a distance of up to 200 m.
Wireless cameras transmit signals without the use of cables. This option is typical for digital devices. Data transmission can be performed using Wi-Fi, Wi-Max, GSM and CDMA technologies. The first option is the most affordable. There are external and internal device types. CCTV cameras over Wi-Fi use frequencies in the 5.15-5.35 and 5.75-7.85 GHz bands. Such devices have some limitations on the amount of information that is transmitted.
Wi-Max is a 4th generation data transmission technology that has no problems with limiting the video stream. However, not all operators support this format. Cameras that transmit information in the GSM format are the most complex and costly. They are equipped with an integrated transmitter. To operate the device, you must register and pay for a SIM card of a mobile operator. If there is no Wi-Fi connection, it is advisable to use the Skiling CDMA format.
CCTV Camerastransmitting information in GSM format have a rather high price
Data transfer format, color rendering of cameras
Depending on the data transmission format, a distinction is made between analog and digital video surveillance cameras. The first type of devices perceives the luminous flux, converting it into an optical signal and transmitting data to the video recorder. The image quality is determined by the type of cable used.
A built-in encoder is responsible for signal conversion in digital cameras. Such devices are characterized by a wide range of applications. They can be wired or wireless. Digital cameras provide high-quality, clear images, provide the ability to reproduce a signal in real time, and are characterized by ease of connection. The duration of the image delay is 300 ms. This type of camera is incompatible with analog devices and has a higher cost.
Important! There are expensive models of digital video surveillance cameras with a microphone on sale.
There is a hybrid version of the camera that combines analog and digital devices. The digital signal is not immediately processed, but is transmitted via fiber optic or coaxial cable to the server. Here, in accordance with the specified parameters, the information is encoded. When the question arises, how much does a hybrid camera cost, we can say that it does not cost more than a digital device.
Video cameras are divided into analog and digital by data transmission format.
Depending on the color rendering, cameras are classified into black and white, color and day / night devices. The first version of the technique has the lowest cost. Devices are undemanding to lighting, are characterized by the ability to store more information than color cameras. This is the ideal solution for organizing a security system.
For the implementation of the internal security of the premises and control over the personnel, video cameras that create a color image are most often used. Day / night devices are versatile devices that can operate in both black and white and color. The choice of color rendition occurs automatically depending on the degree of illumination of the area.If the value falls below the required minimum, the camera starts working in black and white.
Construction options for CCTV cameras
Based on the constructive solution, there are models of cylindrical, body, dome, cubic, rotary, modular and so-called “fisheye” cameras. Cylindrical chambers, due to the elongated canonical shape of the body, are similar in appearance to a rifle bullet. Such a compact device is equipped with a universal bracket for mounting. Camcorders can operate in fixed (3.6 mm) or varifocal (2.8-12 mm) modes. The devices are equipped with IR illumination. They are characterized by the level of weather protection IP66 or IP67, as a result of which they are used as outdoor video cameras for video surveillance.
The most common is the box version of video cameras. Such devices are stationary, provide a fixed location shooting. Outdoor cameras are located in a special thermal casing. The devices are equipped with a 2.8-100mm wide-focus lens. Thanks to the zoom lens, you can change the angle of view and focus. The device is equipped with a special bracket for mounting.
Camcorders are cylindrical, dome, box, cubic, rotary and modular types
To organize control over a large area or objects that are in motion, a dome camera is the best option. The structure includes a rotary mechanism located in the dome, the video camera itself, a zoom lens and a receiver. Thanks to the constant rotation of the device, high-quality panoramic shooting is provided. This camera can be mounted on a wall or ceiling.
For indoor video surveillance, cube cameras are often used. Such devices exercise control over a small area. These cameras are available with a microphone, they are characterized by wireless data transmission. Such models are of low cost.
For large-area coverage, remote control PTZ dome cameras are the best option. The device can be rotated, scaled, changed its viewing angle. The device has a high cost.
The fisheye camera is represented by a panoramic lens. One device can cover a huge area. Due to the fact that shooting is performed with a viewing angle of 360 degrees, the resulting image has a spherical image with distorted straight lines. The price of such cameras is very high.
Dome camera is the best option for monitoring a large area
Modular-type devices are open-board devices with an open circuit board equipped with a microcircuit and a lens that can be inserted into any housing.
Important! The modular camera allows you to organize covert shooting.
Based on the degree of protection, there are dust and moisture-proof, anti-vandal and explosion-proof cameras. The first type of device is protected against dust and moisture, which is reflected in the digital IP indicator. The higher the value, the higher the protection level of the device. Anti-vandal cameras are marked with IK with a two-digit code, which indicates the degree of protection of the device from mechanical damage. Explosion-proof devices with EX value are used in gas-polluted environments.
Characteristics of modern analog CCTV cameras
Analog video cameras for video surveillance are represented by an optical system that creates a signal from the light flux that passes through the lens and the light-sensitive lens of the device, falling on the CCD matrix. The optical signal, converted by a television coaxial cable to analog, is transmitted to a DVR or computer. Information comes in its original form, it is not processed by binary code.
To connect analog video cameras use coaxial cable or RG59
By connecting a monitor, you can view the generated image. For such cameras, only coaxial cable is used, since another option will distort the transmitted signal.
Until recently, these devices had a low resolution, which amounted to 700-800 TVL. Today, manufacturers are releasing advanced HD analog color cameras that are 2.5 times better than the legacy format (5 times Full HD). Thanks to such devices, all the details of the situation can be seen in the image, which was impossible in outdated models.
Depending on the format, the following analog video cameras are distinguished: HD-TVI, HD-CVI and AHD. These technologies practically do not differ from each other. However, the best image detail is provided by TVI format devices. HD-CVI analog devices can transmit video and sound simultaneously.
The cameras are characterized by high resolution (720p), simple design and affordable cost. The devices provide good images even in the dark. The signal is transmitted over a coaxial cable over a distance of 500 m.
Depending on the format, analog cameras can be: HD-TVI, HD-CVI and AHD
Important! To get a good image from an analog camera, it is better to use an RG59 cable.
Installation of modern models allows you to upgrade the old system without replacing communications. The equipment is also characterized by compatibility in all respects. Manufacturers are constantly improving the parameters of the device, adding new features. Modern cameras are distinguished by high sensitivity, extended dynamic range, autofocus, adapted IR illumination, IR filters.
The disadvantages of analog cameras include the lack of an encoding function, which does not provide signal protection. Noise may appear in the picture. Cameras are not capable of zooming in or rotating at the desired angle. The devices do not have a motion sensor and built-in video.
Varieties of analog CCTV cameras
Analog cameras can be classified according to their design features and placement. Devices are stationary and rotary. Cameras of the first type are fixed in one position. The image is recorded exclusively in the field of view. The direction and position of the device can be changed by dismantling and installing in another place. Such cameras are often installed in the staircase. Rotary devices are characterized by a wider range of action, which is provided by rotating the body.
To get a high-quality image of an analog video camera, it is better to connect it with an RG59 cable
Analog cameras can be controlled mechanically or from the dispatcher's workplace. By location, devices are divided into indoor and outdoor. Indoor appliances are installed in a room for any purpose. These devices have good light sensitivity, medium to high resolution. Some models may have a built-in fixed aperture lens. These cameras are hidden.
Outdoor surveillance cameras are used for street photography. The device can be installed anywhere. Cameras allow you to record movements well both day and night, both in the sun and in the shade. The devices are equipped with IR illumination, a focal length adjustment option, and have a high resolution. Outdoor devices can be miniature, standard or domed. Miniature devices can be disguised due to their compact size. It uses mainly a black and white image, but there are also options with a color picture.
Standard outdoor surveillance cameras are equipped with weather protection.Cameras can be rotary and non-rotary. Dome models have increased protection against precipitation and vandalism, and can withstand temperatures up to 30 ° C.
Distinctive features of IP surveillance cameras
IP video cameras for video surveillance are very popular today. Such network devices are equipped with matrices necessary for capturing an image and processors that convert it into a digital signal. The integrated network card redirects data to the web server without using a cable. Monitoring can be performed continuously from any remote location where Internet access exists, without affecting the functionality of the device. When deciding how to connect to a surveillance camera, it is enough to know the IP address of the camera and the password.
Digital IP cameras provide high-quality images with high resolution
The digital camera provides a high resolution of the transmitted signal, after processing which you can recognize the smallest details in the image, even in poor lighting conditions. Some models are equipped with an optical zoom in the form of a movable mechanism with lenses on the lens, which provides fine focusing of the image onto the matrix. You can also change the focal length of the device, which makes it possible to fine-tune over the desired area of interest.
The device can be connected to an existing local network, which reduces the cost of video surveillance installation. Some models of digital cameras have a bi-directional digital audio channel, as a result of which the device turns into an interactive communication device. Thanks to the PoE function, the camera is powered via the same cable as the video signal. Information can be saved on a memory card, computer or in the cloud.
Important! Digital IP cameras allow you to get high-quality images in HD format with a resolution of 1920 × 1080 and higher.
The digital IP camera for video surveillance has a built-in motion sensor. Recording of information to a drive or video recorder can be performed in the presence of changes in the frame, which will reduce the volume of video recordings. The digital signal is difficult to decode. It can only be suppressed with a radio transmitter that operates at the frequency of the LAN / Wi-Fi translator.
In most cases, digital IP cameras have a built-in motion sensor
Among the disadvantages of digital cameras, one can single out their high cost, the complexity of installation and commissioning, which requires certain knowledge of network protocols. Each camera will need to be configured. We can also note the low length of the video line from the camera to the server station. To ensure that the transmission speed does not decrease, you will need to install a signal amplifier.
Varieties of digital video cameras for home video surveillance with online mode
The PNZ camera is very popular, which can be presented in a wall version or in a dome version for placement on the ceiling. The device is distinguished by the ability to scale the image and tilt the frame. The cameras are well protected against strong vibrations. The video is characterized by optimal compression, which is carried out without compromising its quality. This feature allows you to save space in the server room video storage. The device is also characterized by the maximum content transfer rate.
This camera has a protective mask that is triggered in case of intentional or accidental change of the angle of view of the device or the rotation of the lens itself with the sensor unit.
Important! PNZ-camera is able to rotate its "eye" to follow the object of movement.
Panoramic cameras consist of 2-4 wide-angle devices, images from which are superimposed on each other and form a circular panorama
Dome models are equipped with a pivot function, which allows you to "mirror" the transmitted image of the space under the device.Thanks to the Auto-Flip option, the outdoor IP camera can turn 180 degrees, while maintaining the angle of the object under observation. The devices have an optimal tracking angle, which allows the devices to be positioned in such a way as to completely cover the field of view using a minimum of elements.
A panoramic camera consists of 2-4 wide-angle devices, the images of which are superimposed on each other, forming a circular panorama. The video modules are placed on one common ring-shaped base. There are models where modules are combined with matrices to obtain a panoramic image.
Such cameras can operate in one of the modes: a single panorama with a viewing angle of 360 °, two incomplete images of 180 ° each, quadratic video recording at 90 ° and a general picture. The latter is typical for fisheye cameras.
An image can be recorded per file, which is represented by several folders, or as a whole - as a single file. In emergency mode, if the DVR is turned off or there is no Internet access, the video from the surveillance camera is recorded on a memory card that is built into the device.
Dome cameras have an optimal tracking angle
Important! The main disadvantage of a panoramic video camera is the lack of targeted image detailing in a specific place.
Features of Hidden CCTV Cameras
Cameras for covert video surveillance systems do not differ in their technical characteristics from conventional devices. The only feature of such devices is their compact size. The differences are significant when answering the question of how much a hidden camera costs, the price of which exceeds the cost of a conventional device. Such cameras can be easily camouflaged or installed in a place where they cannot be detected by visual inspection. Spy devices can resemble various objects in the form of a lighter, a watch, or a fountain pen. They are often placed on clothing or embedded in office equipment.
Thanks to this feature, hidden IP cameras are characterized by a number of advantages. The cameras are invisible to intruders, thus preventing vandalism or theft. Covert video surveillance does not cause discomfort in people due to the fact that they are in the field of view of the device.
Important! Installation of CCTV cameras, according to the law, in public places is strictly limited.
Cameras for covert video surveillance differ from conventional devices only in their compact size
In your own house or apartment, no one can prohibit the establishment of covert surveillance of domestic staff or monitoring of the environment - indoor and outdoor.
Covert surveillance cameras provide video recording of events and transmit information via cable, wireless system or via a GSM network to a recording device in the form of a video recorder, computer or mobile phone. Some devices have a built-in internal storage - a micro SD card. There are hidden IP cameras with a microphone.
Hidden video surveillance cameras can transmit black and white or color images, be unpackaged or disguised as any object, stationary or portable, wired or wireless, analog or digital, regular size, mini or micro, stand-alone or powered from a network. Mini-video cameras for covert shooting with a long operating mode, which are characterized by reliability, durability and high cost, are in special demand today.
How to choose a CCTV camera: the main criteria
When choosing a video surveillance camera, you should pay attention to the key parameters, taking into account which it will be possible to select a device that provides the necessary overview of the object in existing conditions with minimal operating and purchasing costs.
Camcorders with a small angle of view, able to create the highest possible focus with image detail
The first step is to decide on the installation location. An outdoor or indoor unit is selected based on this criterion. It should be borne in mind that outdoor IP video cameras or analog devices must have a sealed case and be equipped with a built-in heating system for the video surveillance device. The camera must operate smoothly in low temperatures and withstand the effects of precipitation and the sun. If the device is installed outdoors in an area with a high probability of damage to the device, you should pay attention to anti-vandal models.
If the camera will be placed in a damp room, it must have a waterproof housing. Under normal internal conditions, the choice is usually stopped on dome models without a protective case.
The next criteria are the optimal viewing angle of the CCTV camera and the focusing of the image. These parameters determine the video surveillance area and the type of the reproduced picture, which can be portrait, medium-close or panoramic. Cameras with a small angle of view are able to create maximum focus with image detail. However, this option will not provide full visibility of the object.
For observing an object that is at a distance of 30-40 m, models with a viewing angle of no more than 45 degrees are suitable. To cover a large area, it is better to choose equipment with a viewing angle of more than 90 degrees. However, such images will show less detail.
Street analog or IP video cameras must have a sealed case and be equipped with a heating system
Useful advice! You can purchase a varifocal device with a specific focal length range of the camera, where the angle of view is set depending on the situation.
How to choose a camcorder: other important parameters
The sensitivity of the device is selected based on the minimum illumination value, which is measured in lux. If the camera will be used exclusively at night without additional lighting, this parameter should not exceed 0.01 lux. However, such a device must be equipped with a powerful backlight and an infrared filter. An outdoor IP video surveillance camera and an analog device for daytime shooting must have a sensitivity level of at least 5000 lux.
If the camera is designed for 24/7 video shooting, when the light level changes several times, the best option would be devices that have auto iris lenses or built-in electronic shutters. In this case, the image will retain high contrast without darkening and flare due to the fact that the same amount of light will fall on the matrix under different lighting modes.
The next important parameter that affects the ability to enlarge and image detail is the device resolution. If the subject will be surveyed at a great distance or if you need to obtain detailed information, you must select the equipment with the maximum value.
If the camera will be used at night without additional lighting, it must have a powerful backlight and an infrared filter.
For analog devices, resolution is measured in television lines, while for digital devices, it is measured in megapixels. The latter option is more common. Devices can have a resolution of 2-12 megapixels.
Obtaining a high-quality uniform image from a CCTV camera with recording under conditions of different light levels and when focusing on various objects in the frame is made possible by the technology of wide dynamic range.For example, when shooting a person who is looking at the camera and is backlit by bright sunlight, a conventional camera will adjust to the background illumination level, darkening the face, or focus on the face, illuminating the background.
To ensure the same level of illumination for the entire object, you should choose devices with WDR technology, which will allow you to get separable objects without overexposure and deep shadows.
Important! The presence of the WDR parameter is typical for expensive, good premium camcorders.
Camcorders for 24-hour video shooting must have lenses with auto iris
How much does a CCTV camera cost: pricing policy
Today the market offers a large number of video cameras with different technical and operational characteristics, areas of use and prices. The installation of CCTV cameras is based on the needs and financial capabilities of a person.
Affordable models with limited functionality are offered by Chinese manufacturers. The more expensive segment with extended functionality is represented by models of European companies. The cost of a video surveillance camera depends on the type of device, focal length, resolution, body material, presence and range of infrared illumination, data transmission method.
Economy-class devices include cameras with a resolution of 1-2 megapixels, which have low light sensitivity and color rendering. Mainly, this is a dome-type indoor video equipment with a focal length of 3.6 mm. How much does a camcorder cost? The price of the devices is 2-6 thousand rubles. Such cameras are offered by Axilium, Rvі, Space Technology, Prime, Novіcаm, Abron, Optіmus, IPEYE, Fazera.
The widest range of products is in the business class category. The rating of video cameras contains models used for shooting office premises, shops and warehouses. The devices have high light sensitivity, good color rendering, clear illumination, resolution from 1920 x 1080 pixels. The focal length does not exceed 100 mm. The infrared illumination range is no more than 800 m.
Camcorders with low light sensitivity and color rendering belong to the segment of the economy class
This category includes outdoor and indoor models in various designs with different degrees of housing protection. The price of the cameras ranges from 6-30 thousand rubles. The equipment is offered by European brands Mіcrodigіtal, Dahua, D-lіnk, EvеrFocus and Russian companies Fаlcon Eye, Divіtec, Etrovіsion, Beward, TBTEC.
The premium-class category includes expensive devices from Bosch, Beward, Hikvіsion, Microdіgital, AXIS, Samsung, Panasonic, Dahua, the cost of which starts from 100 thousand rubles. The price of hidden cameras can reach 500 thousand rubles. These devices are the best in reliability, durability and functionality. Among them, it is worth highlighting devices with maximum resolution, high image quality, involving face recognition and the smallest details. The models are distinguished by advanced functionality, which includes sound recording, a 360-degree viewing angle, and intelligent elimination of distortion.
CCTV cameras are presented in a wide range. The models differ in design, data transmission method, type of power supply, installation location, technical characteristics and functionality. The choice of the device should be treated with great responsibility in order to obtain reliable, durable equipment that meets the stated requirements.
