To specify a person who performs input from an input device attached to a large screen display device, to associate the person with the input from the input device and to manage an object for operation and a user by associating them with each other by an application in a conference application using the large screen display device.

In a conference system utilizing a monitoring system where a plurality of cameras including a rotary camera capable of performing at least pan/tilt/zoom control catch video images of a mobile object in cooperation, entrance/exit of a conference participant to a conference room is recognized and the recognized conference participant is tracked by the cameras. When the conference participant operates the input device in front of the attached large screen display device, an application program which is displayed on the large screen display device is notified of a user ID of the conference participant and the user ID is associated with an operation of the application.