Method for extracting multiresolution watermark images to determine rightful ownership

• US 6,373,974 B2
• Filed: 09/30/1998
• Issued: 04/16/2002
• Est. Priority Date: 03/16/1998
• Status: Expired due to Term

• Current Assignee: Rakuten, Inc. (Rakuten Group, Inc.)
• Original Assignee: Sharp Laboratories of America Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Zeng, Wenjun
• Primary Examiner(s): Boudreau, Leo
• Assistant Examiner(s): CHOOBIN, BARRY
• Application Number:
  US09/164,231
• Publication Number:
  US 20010016058A1
• Time in Patent Office: 1,294 Days
• Field of Search: 382/135, 382/232, 382/100, 380/4, 209/534, 235/379, 250/200, 356/71, 902/7
• US Class Current: 382/135
• 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

Abstract

A method for embedding and extracting visually imperceptible indicia in an image includes embedding a visually imperceptible indicia in an original image; testing a test image for an embedded visually imperceptible indica; and extracting the visually imperceptible indicia from the test image to determine if the test image is a copy of the original image.

Claims

1. A method for embedding and extracting visually imperceptible indicia in an image, comprising;

embedding a visually imperceptible indicia in an original image;

generating a pseudo random sequence, including using a one-way deterministic function, to a single parameter and using the single parameter as a seed to generate an independent identical distribution pseudo random sequence;

testing a test image for an embedded visually imperceptible indicia; and

extracting the visually imperceptible indicia from the test image to determine if the test image is a copy of the original image, wherein said embedding and said extracting include dividing an image into segments, and wherein said extracting includes making use of neighboring watermark bits to detect the current bit, for an image that has been subject to different levels of signal processing; and

wherein said extracting further includes adaptively selecting a number of segments for watermark detection as a function of the level of signal processing.

2. The method of claim 1 wherein said embedding includes:

designating a visually imperceptible indicia to be embedded in an original image;

selecting a key S₀;

generating a pseudo random sequence S₁ from the key S₀;

modulating the visually imperceptible indicia by the pseudo random sequence to develop a signature; and

inserting the signature into the original image.

3. The method of claim 2 wherein said generating includes mapping S₀, using a one-way deterministic function H, to a single parameter and using the single parameter as a seed to generate an independent identical distribution pseudo random sequence.

4. The method of claim 2 wherein said designating includes designating a one-bit visually imperceptible indicia and wherein said inserting includes implanting a single indicia in the original image.

5. The method of claim 2 wherein said designating includes designating multiple one-bit indicia and wherein said inserting includes dividing the original image into segments and placing a one-bit visually imperceptible indicia into each segment.

6. The method of claim 1 wherein said extracting includes demodulating an image feature set by a pseudo random sequence to determine the presence of the designated visually imperceptible indicia.

7. The method of claim 1 wherein said testing includes:

transforming a test image X into an image feature set X_i;

developing a random sequence S_1i by subjecting a key S₀ to a one-way deterministic function H;

generating a correlating signature S_2i from S_1i and a perceptual model; and

comparing the correlating output to a threshold value to determine the presence of a watermark.

8. The method of claim 1 wherein said embedding includes transforming the original image I into a transformed image I_i.

9. The method of claim 1 wherein said embedding a visually imperceptible image includes embedding a logo image {b_i} and embedding a signature S₀.

10. The method of claim 1 wherein said extracting a visually imperceptible image includes extracting a logo image {b_i} and extracting a signature S₀.

11. A method for embedding and extracting visually imperceptible indicia in an image, comprising:

embedding a visually imperceptible indicia in an original image, including designating a logo image to be embedded in an original image, wherein said designating includes designating multiple one-bit indicia;

selecting a signature S₀;

generating a pseudo random sequence S₁ from the signature S₀, including mapping S₀, using a one-way deterministic function H, to a single parameter and using the single parameter as a seed to generate an independent identical distribution pseudo random sequence;

modulating the logo image by the pseudo random sequence to develop a visually imperceptible indicia; and

inserting the visually imperceptible indicia into the original image;

testing a test image for an embedded visually imperceptible indica; and

extracting the visually imperceptible indicia from the test image to determine if the test image is a copy of the original image including placing a one-bit visually imperceptible indicia into each segment;

wherein said embedding and said extracting include dividing an image into segments and wherein said extracting includes making use of different number of segments associated with neighboring visually imperceptible indicia-bearing bits to detect the current bit, for an image that has been subject to different levels of signal processing, and wherein said extracting further includes adaptively selecting a number of segments for watermark detection as a function of the level of signal processing and of the need for robust detection and degree of resolution.

12. The method of claim 11 wherein said designating includes designating a one-bit visually imperceptible indicia and wherein said inserting includes implanting a single indicia in the original image.

13. The method of claim 11 wherein said extracting includes demodulating an image feature set by a pseudo random sequence to determine the presence of the designated visually imperceptible indicia.

14. The method of claim 11 wherein said testing includes:

transforming a test image X into an image feature set X_i;

developing a random sequence S_1i by subjecting a signature S₀ to a one-way deterministic function H;

generating a correlating signature S_2i from S_1i and a perceptual model; and

comparing the correlating output to a threshold value to determine the presence of a signature.

15. The method of claim 14 which includes comparing the correlating output to a threshold value to determine the presence of a watermark.

16. The method of claim 11 wherein said embedding includes transforming the original image I into a transformed image I_i.

17. A method for embedding and extracting visually imperceptible indicia in an image, comprising:

embedding a visually imperceptible indicia in an original image;

testing a test image for an embedded visually imperceptible indica,

wherein said testing includes transforming a test image X into an image feature set X_i;

developing a random sequence S_1i by subjecting a key S₀ to a one-way deterministic function H;

generating a correlating signature S_2i from S_1i and a perceptual model; and

comparing the correlating output to a threshold value to determine the presence of a watermark; and

extracting the visually imperceptible indicia from the test image to determine if the test image is a copy of the original image;

wherein said embedding and said extracting include dividing an image into segments, and wherein said extracting includes making use of neighboring watermark bits to detect the current bit, for an image that has been subject to different levels of signal processing; and

wherein said extracting further includes adaptively selecting a number of segments for watermark detection as a function of the level of signal processing and of the need for robust detection and degree of resolution, wherein a large number of segments are used to increase robustness and a smaller number of segments are used to increase resolution.