WATERMARKING OF RECORDINGS

摘要

Signals encoded with watermark information are generated and broadcast into a protected area for capture by illicit recording devices along with their intended targets. An illicit recording in which at least a portion of the broadcast watermark signals are recorded is obtained and correlated with a known position of the broadcast watermark signals to yield the location of illicit recording devices. In an alternate embodiment, a surveillance device, being image and time synchronized with a signal broadcasting device, monitors and records the protected area. Illicit recordings containing the broadcast watermark are obtained and correlated with corresponding recordings taken by the surveillance device to identify the location of illicit recording devices. In an alternate embodiment, the surveillance device further monitors the quality of the broadcast watermark signals and adjusts them accordingly to achieve a desired quality level.