The IP camera transmits video in digital form using the transport capabilities of the Ethernet network. In addition to the camera itself, consisting of a lens, an optical filter, a CCD sensor, as well as electronic conversion and signal compression circuits, it is equipped with a network client that provides a standard connection to obtain a dedicated IP address.
The choice of a specific IP camera model is entirely determined by the intended conditions for its use.
What to look for first
Installation location IP-camera: at home or on the street?
One of the most important moments when choosing an IP camera. Chambers for the street and for rooms differ structurally. If the camera is located at the place of direct sunlight, the most effective method of protecting the CCD from burnout is to install a lens with automatic aperture adjustment. In turn, the performance of this node depends on the external temperature, so the cameras in the street version are equipped with a heating system. Devices for indoor installation are equipped with simpler lenses, and the adjustment of the intensity of light in them is performed electronically.
Camera light sensitivity
This parameter is selected depending on the limits of change in illumination in the area under control. For example, for the organization of video surveillance only in the daytime or in the presence of high-quality lighting, for round-the-clock operation, there is enough equipment with a sensitivity of about 0.1 lux. In general, IP cameras with CCD matrixes are more expensive, but have a higher sensitivity than CMOS. At a minimum, one should be guided by CMOS ACS matrices made using more advanced technology with less noise. In low-light conditions, the sensitivity of cameras transmitting a color image decreases sharply. A clearer and more contrasting picture can only be obtained from devices operating in the "day / night" mode. IP cameras with a black and white video signal give the best quality when there is a lack of lighting.
Resolution
Among the most common formats in which modern network IP cameras are capable of transmitting an image are both purely computer, with a 4: 3 aspect ratio (VGA, UXGA, QXGA) or 16: 9 (HD, Full HD), and television standards (PAL). At the same time, a higher nominal resolution does not guarantee that the resulting image will be clearer than from a matrix with a smaller total number of pixels. The reason for blurring may be a low-quality lens, an increase in resolution by interpolation, or software errors during digitization and compression.
Compression format
The choice of the optimal standard depends on the purpose of the IP camera. If it is supposed to be used for automatic recognition of faces or identification of car numbers, attention should be paid to devices with MJPEG compression. In all other cases, the H.264 compression method is preferred.
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Other important features
- In low light conditions, it will not be superfluous infrared light.
- Increase the coverage area will help swivel mechanism and optical zoom (zoom lens).
- Even if the connection is lost, the cameras with a record on Flash-steel will not idle.
- Do not depend on any network problems only the camera with the module Wi-Fi.
- For technology powered devices Poe no need to look for a power outlet.
- To create a professional video surveillance system, use IP cameras. with automatic return to normal operation after abnormal events.
The most popular manufacturers of ip-cameras
The best acclaim from professionals has products of a well-known company. SONY. Very wide range of IP cameras from the company Axis, and in all price segments. The products of the companies also deserve respect. Hikvision, Vivotek, Arecont Vision, Y-cam Solutions and many others.
To buy not upset
When planning to organize video surveillance in low-light conditions, do not aim at cameras with a color video sequence - their sensitivity in the dark drops dramatically.
When purchasing high-resolution IP cameras, make sure that the network bandwidth and video server performance is sufficient to transmit the total stream and process it in real time.
Consider your climate zone when purchasing equipment for outdoor installation. At very low air temperatures, camera actuators operate with increased load and quickly fail if they are not equipped with a heating system.
