Method of extracting a watermark

• US 20060117180A1
• Filed: 04/25/2003
• Published: 06/01/2006
• Est. Priority Date: 05/22/2002
• Status: Active Grant

• Current Assignee: Nagravision SA (Kudelski SA)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Kalker, Antonius Adrianus Cornelis Maria
• Granted Patent: US 8,180,098 B2
• Time in Patent Office: Days
• US Class Current: 713/176
• CPC Class Codes: G06T 1/0028 Adaptive watermarking, e.g. Human Visual System [HVS]-based watermarking
• CPC Class Codes: G06T 2201/0065 Extraction of an embedded watermark; Reliable detection
• CPC Class Codes: G06T 2201/0081 whereby both original and watermarked images are required at decoder, e.g. destination-based, non-blind, non-oblivious
• CPC Class Codes: H04N 1/32144 embedded in the image data, i.e. enclosed or integrated in the image, e.g. watermark, super-imposed logo or stamp
• CPC Class Codes: H04N 21/23892 involving embedding information at multiplex stream level, e.g. embedding a watermark at packet level
• CPC Class Codes: H04N 21/8358 involving watermark protecting executable software by watermarking G06F21/16; image watermarking in general G06T1/0021; watermarks inserted in still images for transmission purposes H04N1/32144; inserting watermarks during video coding H04N19/467

Abstract

A monitoring station (200) for monitoring distribution of media content, on basis of a watermark, comprises: receiving means (202) for receiving an information signal representing the media content to which the watermark is added; extracting means (204) for extracting perceptual features, identifying the information signal; first retrieving means (206) for retrieving a supporting signal on basis of the perceptual features; second retrieving means (208) for retrieving the watermark on basis of the supporting signal; and comparing means (210) for comparing the watermark with predetermined information.

Claims

1. A method of extracting a watermark which is embedded in an information signal, representing media content, comprising:

extracting perceptual features, identifying the media content;

retrieving a supporting signal on basis of the perceptual features; and

retrieving the watermark on basis of the supporting signal.

2. A method as claimed in claim 1, wherein the supporting signal comprises a part of an original signal on which the information signal is based.

3. A method as claimed in claim 1, wherein the supporting signal is derived from the original signal on which the information signal is based.

4. A method as claimed in claim 1, wherein the supporting signal comprises watermark parameters which are appropriate for the information signal.

5. A method as claimed in claim 1, wherein the watermark is representative for an originator of an original signal on which the information signal is based.

6. A method of monitoring distribution of media content, the monitoring on basis of a watermark, comprising:

receiving an information signal representing the media content to which the watermark is added;

extracting the watermark as claimed in claim 1;

and

applying information, being exchanged by means of the watermark, for the monitoring.

7. A monitoring station for monitoring distribution of media content, the monitoring on basis of a watermark, comprising:

receiving means for receiving an information signal representing the media content to which the watermark is added;

extracting means for extracting perceptual features, identifying the information signal;

first retrieving means for retrieving a supporting signal on basis of the perceptual features;

second retrieving means for retrieving the watermark on basis of the supporting signal; and

monitoring means being arranged to apply information, being exchanged by means of the watermark, for the monitoring.

8. A monitoring station as claimed in claim 7, characterized in that the monitoring means are arranged to compare the watermark with predetermined information.

9. A monitoring system for monitoring distribution of media content, the monitoring on basis of a watermark, comprising:

the monitoring station as claimed in claim 7;

and

a storage comprising a mapping of the perceptual features to the supporting signal.