Abstract: A method and apparatus are provided to mark an audiovisual record of a sports event, such as an instant replay recording of a football game, with a preferably graphic indication of an official's whistle signal. An audio input device including at least one mobile transmitter to be worn by one or more of the officials picks up the whistle tone together with ambient sounds. The output of a receiver sensitive to an output of the mobile transmitter is discriminated for the official's whistle signal and may be further discriminated, by use of separate channels or by encoding, to determine which individual official blew the whistle. An encoder then produces a marker which is superimposed on the input to the audiovisual recording device such that the marker appears in the audiovisual record.