Patent ID: 7346514

Claim:
A method for embedding a watermark in an audio signal, comprising the following steps: providing a spectral representation of the audio signal, wherein the spectral representation of the audio signal has a plurality of audio spectral values; providing a spectral representation of the watermark signal, wherein the spectral representation of the watermark signal has a plurality of watermark spectral values; processing the spectral representation of the watermark signal in response to a psychoacoustic masking threshold of the audio signal to obtain a processed watermark signal such that the interference introduced into the audio signal by the processed watermark signal lies below a predetermined interference threshold which depends on the psychoacoustic masking threshold; and combining the processed watermark signal and the audio signal to obtain a watermark-bearing audio signal in which the watermark is embedded, wherein the step of processing comprises the following substeps: selecting a predetermined watermark initial value, which depends on the spectral representation of the watermark signal; determining the interference introduced into the spectral representation of the audio signal by the predetermined watermark initial value after quantization of the spectral representation of the audio signal; and if the interference introduced by the watermark spectral value exceeds the predetermined interference threshold, modifying the watermark initial value until the interference introduced into the spectral representation of the audio signal by a modified watermark initial value after quantization of the audio signal is smaller than or equal to the predetermined interference threshold, and using the modified watermark initial value as the processed watermark signal.