Watermark signal provision and watermark embedding

US8965547B2 · kind B2 · utility

Assignee

• Fraunhofer-Gesellschaft zur förderung der angewandten Forschung e.V. · DE

Inventors

• Stefan Wabnik · Ilmenau, DE
• Joerg Pickel · Happurg, DE
• Bert Greevenbosch · Rotterdam, NL
• Bernhard Grill · Lautenbächle, DE
• Ernst Eberlein · Erlangen, DE
• Giovanni Del Galdo · Martinroda, DE
• Stefan Kraegeloh · Erlangen, DE
• Reinhard Zitzmann · Effeltrich, DE
• Tobias Bliem · Erlangen, DE
• Marco Breiling · Berlin, DE
• Juliane Borsum · Erlangen, DE

Key dates

• Filing date: Aug 23, 2012
• Grant date: Feb 24, 2015
• Expiry date: May 8, 2033

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04H60/33
• WIPO field: Telecommunications
• WIPO sector: Electrical engineering

Abstract

A watermark signal provider provides a watermark signal suitable for being hidden in an audio signal when the watermark signal is added to the audio signal, such that the watermark signal represents watermark data. The watermark signal provider includes a psychoacoustical processor for determining a masking threshold of the audio signal; and a modulator for generating the watermark signal from a superposition of sample-shaping functions spaced apart from each other at a sample time interval of a time-discrete representation of the watermark data, each sample-shaping function being amplitude-weighted with a respective sample of the time-discrete representation, multiplied by a respective amplitude weight depending on the masking threshold, the modulator being configured such that the sample time interval is shorter than a time extension of the sample-shaping functions; and the respective amplitude weight also depends on samples of the time-discrete representation neighboring the respective sample in time.