Watermark decoder and method for providing binary message data

Patent metadata

Field	Value
Publication number	US-9299356-B2
Application number	US-201213589696-A
Country	US
Kind code	B2
Filing date	Aug 20, 2012
Priority date	Feb 26, 2010
Publication date	Mar 29, 2016
Grant date	Mar 29, 2016

Abstract

A watermark decoder includes a time-frequency-domain representation provider, a memory unit, a synchronization determiner and a watermark extractor. The time-frequency-domain representation provider provides a frequency-domain representation of the watermarked signal for a plurality of time blocks. The memory unit stores the frequency-domain representation of the watermarked signal for a plurality of time blocks. Further, the synchronization determiner identifies an alignment time block based on the frequency-domain representation of the watermarked signal of a plurality of time blocks. The watermark extractor provides binary message data based on stored frequency-domain representations of the watermarked signal of time blocks temporally preceding the identified alignment time block considering a distance to the identified alignment time block.

First claim

The invention claimed is:

1. A watermark decoder for providing binary message data in dependence on a watermarked signal, the watermark decoder comprising:
a time-frequency-domain representation provider that provides a frequency-domain representation of the watermarked signal for a plurality of time blocks;
a memory unit that stores the frequency-domain representation of the watermarked signal for a plurality of time blocks;
a synchronization determiner that identifies an alignment time block based on the frequency-domain representation of the watermarked signal of a plurality of time blocks;
a watermark extractor that provides binary message data based on stored frequency-domain representations of the watermarked signal of time blocks temporally preceding the identified alignment time block considering a distance to the identified alignment time block; and
a redundancy decoder that provides binary message data of an incomplete message of the watermarked signal temporally preceding a message comprising the identified alignment time block using redundant data of the incomplete message.

2. The watermark decoder according to claim 1 , wherein the provided binary message data represents a content of a message of the watermarked signal temporally preceding a message comprising the alignment time block.

3. The watermark decoder according to claim 1 , wherein the watermark extractor provides further binary message data based on frequency-domain representations of the watermarked signal of time blocks temporally following the identified alignment time block considering a distance to the identified alignment time block.

4. The watermark decoder according to claim 1 , wherein the memory unit releases memory space comprising a stored frequency-domain representation of the watermarked signal after a predefined storage time for erasing or overwriting.

5. The watermark decoder according to claim 1 , wherein the memory unit releases memory space comprising a stored frequency-domain representation of the watermarked signal after binary message data was acquired by the watermark extractor from the stored frequency-domain representation of the watermarked signal for erasing or overwriting.

6. A method for providing binary message data in dependence on a watermarked signal, the method comprising:
providing a frequency-domain representation of the watermarked signal for a plurality of time blocks;
storing the frequency-domain representation of the watermarked signal for a plurality of time blocks;
identifying an alignment time block based on the frequency-domain representation of the watermarked signal of a plurality of time blocks; and
providing binary message data based on stored frequency-domain representations of the watermarked signal of time blocks temporally preceding the identified alignment time block considering a distance to the identified alignment time block; wherein
the method further includes providing binary message data of an incomplete message of the watermarked signal that temporally precedes a message including the identified alignment time block, using redundant data of the incomplete message of the watermarked signal.

7. A non-transitory computer-readable medium including a computer program for performing, when the computer program runs on a computer, a method for providing binary message data in dependence on a watermarked signal, the method comprising:
providing a frequency-domain representation of the watermarked signal for a plurality of time blocks;
storing the frequency-domain representation of the watermarked signal for a plurality of time blocks;
identifying an alignment time block based on the frequency-domain representation of the watermarked signal of a plurality of time blocks; and
providing binary message data based on stored frequency-domain representations of the watermarked signal of time blocks temporally preceding the identified alignment time block considering a distance to the identified alignment time block; wherein
the method further includes providing binary message data of an incomplete message of the watermarked signal that temporally precedes a message including the identified alignment time block, using redundant data of the incomplete message of the watermarked signal.

8. A watermark decoder for providing binary message data in dependence on a watermarked signal, the watermark decoder comprising:
a time-frequency-domain representation provider that provides a frequency-domain representation of the watermarked signal for a plurality of time blocks;
a memory unit that stores the frequency-domain representation of the watermarked signal for a plurality of time blocks;
a synchronization determiner that identifies an alignment time block based on the frequency-domain representation of the watermarked signal of a plurality of time blocks, to determine a temporal alignment of encoded watermark data relative to the time-frequency domain representation; and
a watermark extractor that provides binary message data based on stored frequency-domain representations of the watermarked signal of time blocks temporally preceding the identified alignment time block considering a distance to the identified alignment time block, to exploit binary message data of messages received before a synchronization by identifying an alignment time block was available; wherein
the identified alignment time block is used to regain binary message data; and
according to the distance to the identified alignment time block, a correct assignment of time blocks preceding the alignment time block to a message can be determined.

9. A method for providing binary message data in dependence on a watermarked signal, the method comprising:
providing a frequency-domain representation of the watermarked signal for a plurality of time blocks;
storing the frequency-domain representation of the watermarked signal for a plurality of time blocks, to determine a temporal alignment of encoded watermark data relative to the time-frequency domain representation;
identifying an alignment time block based on the frequency-domain representation of the watermarked signal of a plurality of time blocks; and
providing binary message data based on stored frequency-domain representations of the watermarked signal of time blocks temporally preceding the identified alignment time block considering a distance to the identified alignment time block, to exploit binary message data of messages received before a synchronization by identifying an alignment time block was available; wherein
the identified alignment time block is used to regain binary message data; and
according to the distance to the identified alignment time block, a correct assignment of time blocks preceding the alignment time block to a message can be determined.

10. A non-transitory computer-readable medium including a computer program for performing, when the computer program runs on a computer, a method according to claim 9 .

11. A watermark decoder for providing binary message data in dependence on a watermarked signal, the watermarks decoder comprising:
a time-frequency-domain representation provider that provides a frequency-domain representation of the watermarked signal for a plurality of time blocks;
a memory unit that stores the frequency-domain representation of the watermarked signal for a plurality of time blocks;
a synchronization determiner that identifies an alignment time block based on the frequency-domain representation of the watermarked signal of a plurality of time blocks; and
a watermark extractor that provides binary message data based on stored frequency-domain representations of the watermarked signal of time blocks

Assignees

• Wabnik Stefan
• Pickel Joerg
• Greevenbosch Bert
• Grill Bernhard
• Eberlein Ernst
• Del Galdo Giovanni
• Kraegeloh Stefan
• Zitzmann Reinhard
• Bliem Tobias
• Breiling Marco
• Borsum Juliane
• Fraunhofer Ges Forschung

Inventors

• Wabnik Stefan
• Pickel Joerg
• Greevenbosch Bert
• Grill Bernhard
• Eberlein Ernst
• Del Galdo Giovanni
• Kraegeloh Stefan
• Zitzmann Reinhard
• Bliem Tobias
• Breiling Marco
• Borsum Juliane

Classifications

• G10L19/018 Primary

  Audio watermarking, i.e. embedding inaudible data in the audio signal · CPC title

• G10L19/00 Primary

  Speech or audio signals analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals, using source filter models or psychoacoustic analysis (in musical instruments G10H) · CPC title