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.