Patent ID: 7383184

Claim:
A method for determining a “fingerprint” in the form of a data set which is characteristic of a particular data signal which is present as a function of time, wherein the data signal itself is searched through for characteristic locations and such characteristic locations are used for producing said “fingerprint”, said method comprising the steps of: specifying time intervals i; transforming the data signal in the time intervals i into the frequency domain in order to obtain a plurality of frequency spectra; for each time interval i, averaging the relevant frequency spectrum over each of a plurality of frequency bands n in order to produce a series of discrete values A i,n ; selecting a time period, comprising several time intervals i, as a characteristic location based on information gained from the data signal and/or from the discrete values A i,n ; and, deriving the characteristic data set from the discrete values A i,n , of the time intervals i lying within the selected time period; whereby, in use, said characteristic data set serves as the “fingerprint” capable of differentiating the particular data signal from other data signals.