The monitor is the standard output of the surveillance system. With the monitor we can view the images sent from the front end. The monitor is divided into color, black and white, sizes 9,10,12,14,15,17,21 inches, etc., commonly used is 14 inches. The monitor also has a resolution and is represented by the same number of lines as the camera. In practice, it is generally required that the number of monitor lines matches the camera. In addition, some monitors have audio input, S-video input, RGB component input, etc. In addition to the audio input monitoring system, the rest of the functions are mostly used for image processing work and are not described here.