Patent ID: 8358376

Claim:
A method, comprising: deriving a first fingerprint from a segment of a first signal related to a first synchronization time point; deriving a second fingerprint from a segment of a second signal related to a second synchronization time point; transmitting the first and second fingerprints to a synchronization device, along with the first and second synchronization time points, or a relationship between the time points, wherein the first and the second signals are not derived from each other or a common source; and storing the first and second fingerprints in association with the first synchronization time point and the second synchronization time point, respectively, in at least one database such that at least one of the first fingerprint or the second fingerprint is searchable for comparison with a fingerprint stream derived from a third signal, the storing including refraining from embedding the first fingerprint or the second fingerprint into the first signal or the second signal.