Abstract: A device for the monitoring of a video installation is disclosed which does not need any intervention into the video sets (television set (4), video recorders (2, 3)). Signal pulses are superimposed on the television or the video signals at the antenna connection (1) and/or the video inputs (7, 8, 10). The superimposition is effected synchroneously to the signal appearing at the respective input (1, 7, 8, 10) in the range of the picture information of a preferably invisible picture line under the control of a processor (14). The burst may also be used for the introduction of digital data which characterize the television or video signal. The retrieval of the burst at the television set (4) is effected either at its video output (10) or by means of a probe (19) fastened at the exterior near the picture tube. For determining the programme reproduced by the television set (4), the presence of the burst as such or the data it contains are sufficient.

Abstract: A method and system for determining the television consumption habits of a test population by obtaining data relating to the program being viewed and/or recorded and transmitting the data through telephone connection to a central computer for evaluation. The data is obtained in a manner which enables the elimination of intervention or supervision by specialized person in the data acquisition process. Any data that is not decoded or is decoded with uncertainty can be determined or verified by means of a dialog with the central computer.