How to solve the problem that the QR code of the rear camera is invalid?

You can take pictures. When scanning a QR code, you can select an album.

Camera or webcam is a kind of video input equipment, which belongs to a kind of closed-circuit television and is widely used in video conferencing, telemedicine, real-time monitoring and other fields. Cameras generally have the basic functions of video shooting, transmission and still image capture. After the image is captured by the lens, the image is processed by the photosensitive element circuit and control element in the camera and converted into a digital signal that can be recognized by the computer. Then it is input into the computer through the parallel port and USB connection, and then the image is restored by software, thus forming a picture. Cameras can be divided into digital cameras and analog cameras. Digital cameras can convert analog video signals generated by video acquisition equipment into digital signals, and then store them in computers. The video signal captured by analog camera must be converted into digital mode by special video acquisition card and compressed before it can be converted into computer. Digital camera can shoot images directly, and then transmit them to computer through serial port, parallel port or USB interface. The cameras in the computer market are mainly digital cameras, and digital cameras are mainly USB digital cameras with new data transmission interfaces, which are mostly visible in the market. In addition, there is another product that works with the video capture card, but it is not the mainstream. Due to the rapid popularization of personal computers, the overall cost of analog cameras is high, and it can not meet the interface of BSV LCD splicing screen. The transmission speed of USB interface is much higher than that of serial port and parallel port, so there are digital cameras with USB interface on the market. Analog camera can be used with video capture card or USB video capture card, which is convenient to connect with computer. The typical application is general video surveillance. Clean area camera, clean area embedded special camera is a special camera for real-time monitoring of key parts of important equipment in clean room. Camera plate, embedded color steel plate, zero sanitary dead angle, convenient cleaning, convenient installation, fast multi-point control, compatible with mainstream video systems.