A properly selected video camera for video surveillance will provide the necessary overview of the perimeter in the room or on the site with low procurement costs. Now many of their varieties are proposed, so as not to get confused in such a variety, it is important to study the technical characteristics of video devices.
Types of video cameras for video surveillance
First we need to map out for what needs the device will be applied, its technical parameters. For example, before choosing an outdoor surveillance camera, it is important to know that the housing of such a device must be sealed, preferably equipped with a warm-up function. To organize tracking inside the room, dome chambers without protective hoods are often installed. In addition, all video detectors are divided into analogue, digital. The main difference between them is in the way the video signal is processed and transferred.
Digital video cameras for video surveillance
The advanced digital IP video camera for video surveillance data from the matrix in digitized form via Wi-Fi, 3G , 4G or wire Internet sends to the cloud server, PC, DVR. Digital video cameras produce a picture as HD (720p), Full HD (1080p), and above - 4K (up to 12Mp). On the video, you can look at the common features of a person, and his face, different small details. If you focus on the quality of the picture (especially when it is detailed), then when deciding which surveillance cameras are best, you should stop at the digital IP model. Advantages of IP technology:
- A high resolution.
- The presence of an IP address, the desired camera can be determined on the Internet.
- Possibility of archiving to the server.
- The processor compresses the data, which reduces the load on the network.
Analog video cameras for video surveillance
Known analog video cameras work with PAL and NTSC signals, connect directly to the display with a cable. If you need to record what is happening, you need to connect to the computer or DVR network. Early devices could not give out a picture with high resolution and lost the quality of the image digitally. Two years ago in the market of analog models there was a breakthrough - the newest standards appeared:
- AHD;
- HD-TVI;
- HD-CVI.
Now, even analog cameras produce a quality corresponding to HD (720p) and Full HD (1080p). In 2017 3 and 4 megapixel models went on sale. So a modern analog video camera for video surveillance is able to compete with IP models. A number of its obvious advantages:
- Infrastructure is not subject to hacker and virus attacks.
- Transmits the picture in real time without delay.
- Low cost, easy installation.
- The interconnection of devices released by different brands.
- An analogue street video camera for video surveillance shows itself perfectly regardless of the illumination.
- It is worth giving them preference when you need to shoot in motion.
What are surveillance cameras?
A modern video camera for video surveillance is an integral part of the security system. This technique performs different types of tasks, depending on the performance characteristics, the price for it can vary significantly. Classification of video cameras for video surveillance in the place of installation:
- Street - are fixed outside the building.
- Internal - it is not supposed to be used outdoors.
By the method of data transmission:
- Wired - signal is sent via fiber, twisted pair, coaxial cord.
- Wireless - the installation of the network is not required, you need power.
By color reproduction:
- Color - shooting is exclusively in color mode.
- Black and white - they can be used in case of lack of lighting or in total darkness with infrared illumination.
- Day / Night - in the dark, the video fader moves from color mode to black and white.
In appearance:
- Cylindrical - made in the form of a cylinder.
- Modular - bare board without case.
- Dome -shell has the form of a hemisphere.
- Fisheye - panoramic devices with ultra-wide view.
Internal video camera for video surveillance
The modern internal video camera for organizing video surveillance for the house is fixed from inside the building, it differs in smaller dimensions and weight. It does not have protection from adverse external influences and should fit organically into the interior. The case of such a device has no claims for tightness, there are no visors on it. For video surveillance of the room, you can use compact video cameras with a small photosensitivity or hidden models equipped with Wi-Fi, a microphone, a motion detector.
Outdoor video camera for video surveillance
The operation of outdoor video cameras for video surveillance is associated with the need to protect the device from low temperatures, rain, sun, dust. Therefore, they are placed in sealed enclosures, inside which there are heaters. The degree of protection of devices is determined by abbreviation. Dust-proof, IPXX, where XX is the degree of protection (the first is from dust, the second is from moisture). For example, the IP65 device is dust-proof, but it is installed under the visor on the street, and IP68 can be immersed even under water.
Outdoor use often involves anti-vandal protection, and night work - infrared illumination. Camcorders for outdoor video surveillance are removed far from the monitor, so they must be able to transmit quality data over long distances. Often for the street use cylindrical, dome or rotary models.
Camcorders for the latent video observation
Organize video surveillance can be a hidden camera. They are let out so that the object did not see, that it remove. A hidden camcorder for video surveillance can be disguised as a subject, for example, a briefcase or a book. There are miniature models, the sizes of which do not exceed the size of the match head. Such a lens is installed in the wall, on the surface there is only a lens. Before choosing a hidden surveillance camera, it is important to know that secret surveillance of an object is illegal.
Video camera with a microphone for video surveillance
With the development of CCTV, the system was improved with the availability of audio. In the market there are many cameras with a built-in microphone with great clarity and sensitivity, which can intelligibly record the speech of the object. Video camera for video surveillance with sound helps to get accurate information about the situation on the protected object, in time to detect the threat. Some models are equipped with speakers that convey the dispatcher's speech to the object.
Wireless video camera for video surveillance
Advantages differ from wired devices in the absence of costs for cable routing wireless analogues. They send a signal using 3G, 4G, Wi Fi technology, while the electricity to the device itself comes through the wire. But the radius of their action is limited and the cost is higher than the wired analogues. Wireless models are divided into several groups:
- Video cameras Wi-Fi for video surveillance, it's IP models that work through the access point.
- WEB - model, it is a set: camera - transmitter - receiver - USB interface converter (plus special software).
- GSM - sends data over the channels of cellular communication (range is limited to the operator's coverage area).
Camcorder for video surveillance with zoom
A modern video camera for video surveillance with zoom is added with a built-in ZOOM lens. It is more flexible to use than a fixed focus. Thanks to the ZOOM-lens, a video camera for indoor or outdoor shooting is capable of approximating or detaching objects. Range of adjustment of distance - from 6: 1 to 50: 1. Camcorders with built-in zoom have high-tech stuffing, are more expensive than analogues, they have large dimensions and power consumption. The purchase of such products should be justified, it is advisable to use them in rotary chambers.
Camcorders with motion sensor for video surveillance
The principle of the camera with a motion sensor is a reaction (programmed in advance) to move an object in the field of view. She can:
- start recording information;
- turn on the siren;
- send a signal to the monitor, highlighting the moving object in the frame.
Motion detectors are activated automatically or manually. They are mainly infrared, differ in range (no more than 6 m), in viewing angle (often 70 °). Before choosing an outdoor surveillance camera for a home with a motion sensor, it is important to know that it is logical to install it where the flow of people is not very intense, so that the recording starts when necessary.
Rotary CCTV Cameras
For shooting in a spacious area it is better to choose a turntable for video surveillance. It is equipped with a mechanism that changes the viewing angle of the device. The swivel camera automatically or the control panel turns the lens and fixes what is happening around. The function helps to reduce the number of video devices on the site, without limiting the area of view. Most rotary cameras are capable of approximating the video being shot. Devices can be programmed for a sequence of rotation of the lens, indicating the angle of rotation and periodicity.
Panoramic CCTV Cameras
Modern panoramic cameras provide a full 360 ° view. They help to see the whole picture on the protected area entirely with a minimum of "blind spots". When deciding which surveillance cameras are best, it is worth considering that panoramic models can replace several fixed and more effective rotary ones. Equipped with a motorized mechanism, the instruments control the objects in a circular view. A popular option is a dome model with a fish eye lens mounted on a ceiling or wall. It is advisable to use it in areas that do not abound with partitions.
Characteristics of a video camera for video surveillance
Choose the camera is recommended taking into account its main characteristics:
- Resolution. Determines the degree of detail of the picture, everything is simple - the more, the better. For analog cameras it is measured in television lines TVL (from 380 (~ 0.3 Mp) to 1000 (~ 2 Mp)), for IP cameras - in megapixels (minimum - 1 Mp, the best video cameras for high-resolution video surveillance have indicators up to 12 Mp, which corresponds to the standard 4K).
- Sensitivity. Determines the minimum level of illumination, measured in lux. For functioning at night without illumination, this parameter should not exceed 0.1 lux. A useful advantage is the presence of an infrared filter.
- Viewing angle and focus. Define the coverage of the tracking zone and the type of image (panoramic, medium-approximate, portrait). Cameras with a viewing angle of 90 ° can cover the entire room more fully, but then when viewing the video you can disassemble less details.
Also, when buying, pay attention to the presence of infrared function, rotation, distance of night shooting, the material of the body, the speed of video recording, the format of the digital video file, the dimensions and weight of the device. Another device can have a built-in microphone (with a different threshold of sensitivity), a memory bar (of different volume and format).