August 17, 2022
There are too many classification standards for security cameras. If the standards are too trivial and the classification is too fine, many cameras will appear in different classifications at the same time, which is not conducive to grasping the entire security camera system as a whole. According to my own experience, combined with the classification standards of industry leaders such as Hikvision, Dahua, Uniview, Axis, etc., the classification is as follows:
01 Video output signal
For security cameras, the light passes through the lens and irradiates on the image sensor sensor inside the camera. At this time, it is still an analog signal, which is converted into a digital signal through A/D, processed by ISP or DSP, and then output video signal. Before output, if D/A conversion is performed again, that is, the digital signal is converted into an analog signal for output. This kind of camera is generally called an analog camera. The common ones are cvbs analog standard definition cameras (basically eliminated), XVI/TVI/CVI/ AHD and other high-definition analog cameras. If the direct output is a digital signal, it is called a digital camera. For example, an SDI camera is a digital camera, which is often used in video conferences. According to the transmission rate, SDI can be divided into SD-SDI, HD-SDI and 3G-SDI. Generally, the SDI camera used for security is HD-SDI or 3G-SDI.
In the third case, in order to reduce the amount of data transmitted, the digital signal is encoded and compressed according to a certain method standard (such as H.264, H.265, H.266) and then output. This camera is a network camera.
According to the shell of the camera, it can be divided into bolts, barrels, hemispheres, balls, PTZs, etc.
The so-called bolt, also called box camera, looks like a box, and can be equipped with a C/CS interface lens without additional fill light. The various interfaces of the camera are generally at the rear. If installed in an outdoor environment, this camera requires an additional protective cover. Tube camera, generally refers to infrared shotgun camera, lens, infrared or white light fill light, the camera itself is combined together, the appearance can reach the protection level of IP66, IP67, the various interfaces of the camera are solved by the tail line at the rear, commonly used in an outdoor environment. Suitable for wall mounting or hoisting, some drum machines come with mounting brackets. In some installation environments, such as the ceiling is not suitable for the installation of gun-type and barrel-type cameras, a dome camera needs to be used at this time to facilitate ceiling or embedded installation on the ceiling. The internal structure of the camera, the function of the dome camera and the barrel camera are exactly the same. Combine the camera, the pan/tilt that controls the camera to rotate up and down, and additional fill lights, etc., and put them into a spherical shell. This kind of camera is generally called a spherical camera. In addition to the functions of general cameras, the dome camera also supports PTZ, that is, horizontal rotation (Pan), vertical rotation (Tilt), lens zoom, focusing (Zoom) and other functions to achieve 360-degree omnidirectional, long-distance No dead angle monitoring. The dome camera is equipped with different mounting brackets, which can support wall mounting, ceiling mounting or embedded mounting. If a camera with PTZ function does not have an additional spherical protective cover, the camera is directly placed on the PT pan/tilt, such a camera is called a pan-tilt camera. Except for the different appearance, the others are exactly the same as the dome camera. The advantage of this appearance of the camera is that it is convenient to be placed on a horizontal platform, such as the roof of a car, and various work consoles.
Whether it is a network, analog, or digital camera, it can be classified according to the pixels and resolutions it supports. From standard definition cameras with hundreds of megapixels to 12 million 4K resolution HD cameras
General standard definition camera, if it is analog, we will call it cvbs or 960H camera directly, not directly named by pixels. If it is a network, it is directly called a standard definition or SD camera. 720 resolution, and those above megapixels are directly named with pixels/resolution. For example, 1 million, 2 million, 3 million, 5 million, 8 million, 12 million, if named after the resolution, it is 720P, 1080P, 4K, or HD, FHD, UHD.
04 Fill light
The camera is a color image during the day. In the environment where the ambient light is very weak or completely dark at night, it needs to use a fill light to image. Of course, some cameras, such as star-level ones, can still present colorful video images as long as there is weak light. According to whether additional fill light is needed, the cameras can be divided into infrared cameras (which can be further divided into 850 nm infrared and 940 nm infrared), white light fill light/warm light cameras, and starlight full-color cameras.
In some explosion-prone occasions and environments, such as oil refineries, pipeline gas transmission, oil and gas exploration, mining, etc., as well as oceans, ships and other highly corrosive environments such as salt, acid and alkali, special The camera made of exterior material is used for explosion-proof and anti-corrosion.
06 Field of use
With the development of chip technology, software technology, network technology, etc., security cameras have gradually moved from the professional field to the ordinary civilian market, and more and more home WiFi cameras have entered thousands of households. According to the different fields of use, security cameras can be divided into professional fields and ordinary households. Ordinary home cameras mainly support WiFi distribution network, TF card or cloud storage, simple AI functions (such as humanoid detection, voice alarm, etc.), mobile APP management, etc.
07 Special scene
For different scenarios and monitoring purposes, we need to choose cameras with different functions. For example, for parking lots, license plate recognition cameras are required. In terms of intelligent transportation, it is necessary to use intelligent transportation cameras with functions such as illegal capture, license plate recognition, and traffic flow statistics. There are also industrial cameras that support machine recognition, cameras that support number and face statistics, video conferencing cameras, thermal imaging cameras, cameras that support wide dynamic/strong light suppression, and mini/pin for special occasions (such as bank ATM machines). Hole cameras, wearable cameras for mobile law enforcement.
08 Video output interface
Cameras can be classified into these types according to the video signal output interface.
Mainly analog cameras, such as cvbs/960H, AHD/CVI/TVI/XVI, etc. SDI cameras generally also use BNC connectors to output digital signals.
RJ45 network port
Usually a webcam.
Digital cameras, such as SDI cameras, can output video signals directly through HDMI. Before encoding, the network camera can also output digital video signals directly through HDMI.
Video signals are output through serial ports, such as RS-485, 232, and TTL interfaces. Generally, this camera is mostly used for docking with other hardware devices, such as industrial control, electrical power, water conservancy environmental monitoring equipment, law enforcement and forensics equipment, etc.
The camera with USB interface is actually a kind of serial camera, which is divided into a separate category here. It is intended to refer to the camera that is connected to the computer through the USB interface and can collect video images in the computer software. It can generally be used for video chat and video conference functions on computer software.
The network camera, with an optical fiber interface, transmits video signals through optical fiber, eliminating the need for additional steps to configure optical fiber transceivers.
This type of camera is mainly used in vehicles. Various cables such as video and power are gathered together to form an independent interface, which is easy to plug and unplug, and is stable and reliable.
According to the type of lens used, the number of lenses can classify the security camera like this: Of course, according to the aperture of the lens, it can also be divided into fixed aperture lens, manual aperture lens, and automatic aperture lens. Auto iris can also be divided into DC drive iris lens, video drive iris lens, P-iris lens, i-CS lens and so on.
10 Signal transmission
According to the transmission method and transmission medium used, security cameras can be divided into coaxial video line transmission, twisted pair transmission, power line transmission, optical fiber transmission, WiFi transmission, 4G transmission, etc.
It should be noted that with the help of some conversion transmission equipment, such as coaxial network transmitters, coaxial video cables can be used to transmit network camera signals. Similarly, with the help of twisted pair transmitters, a pair of 2 mountain-stranded cables can also be used to transmit analog camera signals. With the aid of corresponding power line transmitters, network camera signals or analog camera signals can be transmitted over the power line.
Cameras use different power supplies, commonly used are AC24, DC12, DC5V, etc. According to the different power sources used, solar energy or batteries, 18650 batteries, etc. can also be configured to power the camera.
|Contact Person :||Ms. Elaine|