Watermark signal provider and method for providing a watermark signal

摘要

A watermark signal provider comprises a time-frequency-domain waveform provider to provide time-domain waveforms for a plurality of frequency subbands. The time-frequency-domain waveform provider is configured to map a given value of a time-frequency-domain representation onto a bit shaping function, a temporal extension of which is longer than a bit interval, such that there is a temporal overlap between bit shaped functions provided for temporally subsequent values of the time-frequency-domain representation of the same frequency subband. A time-domain waveform of a given frequency subband contains a plurality of bit shaped functions provided for temporally subsequent values of the time-frequency-domain representation. The water mark signal provider further has a time-domain waveform combiner.

主权项

1. A watermark signal provider for providing a watermark signal in dependence on a time-frequency-domain representation of watermark data, in which the time-frequency-domain representation comprises values associated to frequency subbands and bit intervals, the watermark signal provider comprising:
a time-frequency-domain waveform provider configured to provide time-domain waveforms for a plurality of frequency subbands, based on the time-frequency-domain representation of the watermark data, wherein the time-frequency-domain waveform provider is configured to map a given value of the time-frequency-domain representation onto a bit shaping function, wherein a temporal extension of the bit shaping function is longer than the bit interval associated to the given value of the time-frequency-domain representation, such that there is a temporal overlap between bit shaped functions provided for temporally subsequent values of the time-frequency-domain representation of the same frequency subband; and wherein the time-frequency-domain waveform provider is further configured such that a time-domain waveform of a given frequency subband comprises a plurality of bit shaped functions provided for temporally subsequent values of the time-frequency-domain representation of the same frequency band; and a time-domain waveform combiner, to combine the provided time-domain waveforms for the plurality of frequencies of the time-frequency-domain provider to derive the watermark signal; wherein the time-frequency domain waveform provider is configured such that a bit shaped function provided for a given value of the time-frequency domain representation is overlapped with a bit shaped function of a temporally preceding value of the same frequency subband as the given value of the time-frequency domain representation and with a bit shaped function of a temporally following value of the same frequency subband as the given value of the time-frequency domain representation, such that a time domain waveform provided by the time-frequency domain waveform provider comprises an overlap between at least three temporally subsequent bit shaped functions of the same frequency subband.