Reducing Watermark Perceptibility and Extending Detection Distortion Tolerances

• US 20110216936A1
• Filed: 03/07/2011
• Published: 09/08/2011
• Est. Priority Date: 03/05/2010
• Status: Active Grant

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Reed, Alastair M., Rodriguez, Tony F.
• Granted Patent: US 8,477,990 B2
• Time in Patent Office: Days
• US Class Current: 382/100
• CPC Class Codes: G06T 1/0021 Image watermarking
• CPC Class Codes: G06T 1/0028 Adaptive watermarking, e.g. Human Visual System [HVS]-based watermarking
• CPC Class Codes: G06T 1/005 Robust watermarking, e.g. average attack or collusion attack resistant
• CPC Class Codes: G06T 1/0064 Geometric transfor invariant watermarking, e.g. affine transform invariant
• CPC Class Codes: G06T 2201/0051 Embedding of the watermark in the spatial domain
• CPC Class Codes: G06T 2201/0065 Extraction of an embedded watermark; Reliable detection
• CPC Class Codes: H04N 1/32352 Controlling detectability or arrangements to facilitate detection or retrieval of the embedded information, e.g. using markers for decoding, detection or retrieval operations H04N1/32149 and subgroups take precedence
• 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

The present disclosures relates generally to digital watermarking and data hiding. One claim recites a method comprising: obtaining data representing video; using one or more programmed electronic processors, embedding a first watermark signal in a first portion of the data, the first watermark signal comprising a first signal polarity; using one or more electronic processors, embedding a second watermark signal in a second portion of the data, the second watermark signal comprising a second signal polarity that is inversely related to the first signal polarity; rendering the watermarked video in real time, in which due to temporal averaging of the first watermark signal and second watermark signal over time, the first watermark signal and the second watermark signal are hidden from a human observer of the video. Of course, other claims are provided too.

Claims

1. A method comprising:

receiving data representing video captured from a display rendering such video;

searching the data for hidden indicia, the indicia providing information to allow a determination of video capture distance and video capture perspective;

upon encountering the hidden indicia, using the information to warp the data to compensate for distortion caused by video capture distance or video capture perspective;

provided the warped data to an electronic processor programmed as a steganographic indicia decoder, said decoder analyzes the warped data to decode steganographic indicia hidden in video captured from the video display.

2. A non-transitory computer readable medium comprising instructions stored thereon to cause one or more electronic processors to perform the method of claim 1.

3. A cell phone programmed to perform the method of claim 1.

4. A cell phone running an application to cause the cell phone to perform the method of claim 1.

5. A method comprising:

obtaining data representing video;

using one or more electronic processors, embedding a first watermark signal in a first portion of the data, the first watermark signal comprising a first signal polarity;

using one or more electronic processors, embedding a second watermark signal in a second portion of the data, the second watermark signal comprising a second signal polarity that is inversely related to the first signal polarity;

rendering the watermarked video in real time, in which temporal averaging of the first watermark signal and second watermark signal over time conceals the first watermark signal and the second watermark signal from a human observer of the video.

6. The method of claim 5 in which the first watermark signal and the second watermark signal are embedded in corresponding spatial positions of the video.

7. A non-transitory computer readable medium comprising instructions stored thereon to cause one or more electronic processors to perform the method of claim 5.

8. An electronic computing device programmed to perform the method of claim 5.

9. A method comprising:

obtaining data representing video;

using one or more programmed processors, embedding a watermark signal in a first portion of the data, the embedding using a first embedding bump size;

using one or more electronic programmed processors, embedding a watermark signal in a second portion of the data, the embedding using a second embedding bump size,

in which the first embedding bump size corresponds with a first detection range distance when capturing optical scan data associated with the video as it is being rendered on a display, and the second embedding bump size corresponds with a second, larger detection range distance when capturing optical scan data associated with the video as it is being rendered on the display.

10. The method of claim 9 in which use of both the first embedding bump size and the second embedding bump size extends the detection range distance when capturing optical scan data associated with the rendered video.

11. The method of claim 9 in which the optical scan data comprises video data captured from a display that is rendering the video.

12. The method of claim 9 in which the first portion of the data comprises two or more video frames.

13. The method of claim 12 in which the second portion of the data comprises two or more video frames.

14. A non-transitory computer readable medium comprising instructions stored thereon to cause one or more electronic processors to perform the method of claim 9.

15. An electronic computing device programmed to perform the method of claim 9.

16. A cell phone comprising:

a camera to capture video of a display that is rendering video;

electronic memory for buffering data representing captured video;

one or more electronic processors programmed for;

analyzing the captured video, in which the video comprises a watermark signal embedded in a first portion of the data, the embedding using a first embedding bump size, and a watermark signal embedded in a second portion of the data, the embedding using a second embedding bump size, and in which the first embedding bump size corresponds with a first optimal detection range distance when capturing optical scan data associated with the video, and the second embedding bump size corresponds with a second, larger optimal detection range distance when capturing optical scan data associated with the rendered video.

17. A method comprising:

obtaining a watermark signal;

using one or more programmed electronic processors, embedding a watermark signal in a first portion of a video signal;

preconditioning the watermark signal in a first manner to allow expanded detection of said preconditioned watermark signal in the presence of first distortion;

using one or more programmed electronic processors, embedding the watermark signal preconditioned in the first manner in a second portion of the video signal;

preconditioning the watermark signal in a second manner to allow expanded detection of said preconditioned watermark signal in the presence of second distortion;

using one or more programmed electronic processors, embedding the watermark signal preconditioned in the second manner in a third portion of the video signal.

18. The method of claim 17 in which the first distortion is due to positive image capture perspective angle variance.

19. The method of claim 18 in which the second distortion is due to negative image capture perspective angle variance.

20. The method of claim 18 in which image capture perspective angle variance is introduced by a mobile device capturing imagery of a display that is rendering the watermarked video signal.

21. The method of claim 19 in which image capture perspective angle variance is introduced by a mobile device capturing imagery of a display that is rendering the watermarked video signal.

22. The method of claim 17 in which said embedding the watermark signal preconditioned in the first manner in a second portion of the video signal uses a first embedding bump size;

and in which said embedding the watermark signal preconditioned in the second manner in a third portion of the video signal uses a second embedding bump size; and

in which the first embedding bump size corresponds with a first optimal detection range distance when capturing optical scan data associated with the video signal as it is being rendered on a display, and the second embedding bump size corresponds with a second, larger optimal detection range distance when capturing optical scan data associated with the video signal as it is being rendered on the display.