Methods for decoding auxiliary control information from audio and using same to control an audio appliance. Various arrangements are disclosed. One method correlates a filtered version of the audio with predetermined noise data to discern plural bits of hidden data. The data thereby extracted is used...http://www.google.se/patents/US6587821?utm_source=gb-gplus-sharePatent US6587821 - Methods for decoding watermark data from audio, and controlling audio devices in accordance therewith
