This invention relates to security for
data objects; more particularly, the present invention relates to improved security based on subliminal and supraliminal channels for
data objects.In one embodiment, a method for protecting a
data signal comprises: providing a
data signal to be encoded; using a first predetermined key to
encode a first set of
independent data into the
data signal imperceptibly; and using a second predetermined key to
encode a second set of
independent data into the data
signal perceptibly.In another embodiment, a method of protecting a data object comprises: steganographically encoding a subset of candidate bits in a digitized sample
stream; perceptibly manipulating data in the digitized sample
stream; and combining the imperceptible and perceptible data changes to create a secure / unique digital sample
stream.In yet another embodiment, a method for securing a data
signal comprises: preanalyzing said data
signal for candidate
watermark / signature bits; steganographically encoding
independent data into the data signal into a subset of the candidate
watermark bits, at least one time; and encoding the data signal subsequently with a perceptible technique.In yet another embodiment, a method of protecting a data signal comprises: imperceptibly embedding data using a watermarking technique; perceptibly signing the data using the
receiver's public key; encrypting the data signal using the
receiver's public key and the private key used to
watermark the signal; and enabling a
receiver to authenticate / verify (separate steps) the data signal while connected to a communications channel.