For embedding binary payload in a carrier signal, which, for example, is
an audio signal, a sequence of time-discrete values of the carrier signal
is converted to the frequency domain by means of an integer transform
algorithm to obtain binary spectral representation values. Bits of the
binary spectral representation values with a valency less than signal
limit valency are determined and set according to the payload. The signal
limit valency for a spectral representation value is less than the
valency of the leading bit of this spectral representation value, so
that, with adequate distance, a psychoacoustic transparent insertion of
information is achieved. Thus a modified spectral representation with
inserted information is generated which is finally converted back to the
time domain using an integer back transform algorithm. For extracting the
payload, the time-discrete signal with the inserted information is again
converted to a spectral representation with the integer forward transform
algorithm. Furthermore, signal limit valency information is determined to
identify the bits of the binary spectral representation values containing
no information regarding the carrier signal, but information regarding
the payload signal, to extract these bits. The inventive concept is
simple in its implementation and may be scaled with respect to the data
rate of the information to be inserted.