There are many types of access control intercom systems. In addition to visual intercom and non-visual intercom, they can also be divided into black and white interface and color interface, analog communication and digital communication.
The feature of the visual intercom system is to identify the identity of the visitor, and the features of the visitor can be seen through the intercom screen. In the beginning, some video intercoms were only capable of one-way video, that is, a visiting relationship must be established. Nowadays, the video intercom system can actively send out signals to view the situation at the entrance of the building through the outdoor camera of the unit door.
However, video intercom devices also face a criticism-camera clarity. Let’s not talk about the situation under the light intensity, but based on the normal conditions during the day, the author has discovered such a problem. Take the above picture as an example. This is a video intercom indoor unit in a residential area. Whether it is seen directly from the naked eye or from the effect of the photo remake, the backlight phenomenon is very serious. As for the visitor, it is not clear at all.
The definition of the camera is not enough, and the camera does not have general functions such as noise reduction and light suppression. Of course, this camera cannot be compared with a surveillance camera, but the user also needs to see the image clearly during use, at least within 2 meters of the visitor's gender and outline.
In addition to the fact that the camera is not clear, the screen of the video intercom device will also be disturbed to a certain extent, which is the drawback of the bus system. Occasionally, there will be problems with unclear call sound quality. If large communities want to realize networked management, the transmission distance must be increased, and the long-distance transmission of the bus system needs to increase the video amplifier, and the cost is high.
Therefore, this wired video intercom system has the problems of troublesome construction, inconvenient use, interference and unclear images. Then came the birth of wireless video intercom.
Wireless video intercom doorbell is the second line of defense for home security. The function is similar to the traditional cat's eye, and it is the second line of defense for your home security loyalty. But his function is more comprehensive than cat's eye, and the safety factor is higher. In addition to allowing you to clearly see who the visitor is, you can also automatically and manually take photos and store images, and you can talk to the visitor in two ways, and you can also actively send out signals to check the situation in front of your door. Docking with the electronic lock to realize wireless remote control unlocking. To achieve these functions, any role of the host in the room can be done.