For starters, your camera’s image resolution must be at least 1080p.Next you must determine the viewing angle. The wider the angle, the more people the camera can detected.Ideally you should look for a camera with a 180° viewing angle.Lastly, you must take into account the distance between the camera and the people you want to detect. This will help you determine the size of the lens.Choose a 4 millimeter lens to detect and recognize visitors up to 6 meters from the camera. Select a 8 millimeter lens when people are up to 12 meters away, and so on. Navori Labs offers cameras that are suitable for distances between 3 and 25 meters away, thanks to an optional telephoto lens.