Apparatus and method for encoding and decoding information in analog signals

摘要

Apparatus and methods are provided for encoding, storing and decoding auxiliary information on an analog source signal in a way which has minimal impact on the human perception of the source information when the source signal is applied to an appropriate output device, such as a speaker or a display monitor. The autocorrelation function of a host signal is modulated according to the value of an auxiliary information signal by adding a host modifying signal to the host signal. The auxiliary signal is decoded by generating the autocorrelation function of the encoded signal and extracting the auxiliary signal according to well-known signal extraction techniques.