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US6590996B1 Expired / Lapsed US ⏱️ 0.0 years remaining

Color adaptive watermarking

Assignee: Digimarc Corp
•
Filing: 2000-04-19
•
Granted: 2003-07-08
•
Expires: 2020-04-19
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Abstract

Abstract A color mapping process enhances a watermark by computing a change in colors that is less visible for a given watermark strength. The mapping process provides smooth transitions from one color region to another, and may be implemented efficiently with a 3D look up table. A user interface scheme enables the user to control encoding of the watermark in desired color regions.

Inventors

  • 👤 Alastair M. Reed
  • 👤 Geoffrey B. Rhoads

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 18:55
CPC Classifications
G; G06; G06T; G06T1/00; G06T1/0021; G06T1/0028; G06T1/005; G06T1/0064; H; H04; H04N; H04N1/00; H04N1/32; H04N1/32101; H04N1/32144; H04N1/32149; H04N1/32154; H04N1/32203; H04N1/32208; H04N1/32229; H04N1/32251; H04N1/32288; H04N1/32293; H04N1/32309; H04N1/32352; H04N19/00; H04N19/46; H04N19/467; H04N19/60; H04N19/63; H04N19/64; H04N19/645; H04N21/00; H04N21/20; H04N21/23; H04N21/238; H04N21/2389; H04N21/23892; H04N21/40; H04N21/43; H04N21/44; H04N21/44008; H04N21/45; H04N21/462; H04N21/4627; H04N21/80; H04N21/83; H04N21/835; H04N21/8358; H04N7/00; H04N7/16; H04N7/162; H04N7/163; G06T2201/00; G06T2201/005; G06T2201/0051; G06T2201/0052; H04H; H04H20/00; H04H20/28; H04H20/30; H04H20/31; H04N2201/00; H04N2201/32; H04N2201/3201; H04N2201/3225; H04N2201/3233; H04N2201/3269; H04N2201/327; H04N2201/328; H04N2201/3284

Claims Analysis

Total Claims: 24
Claim 1
Independent Claim 101 words
In a watermark encoder, a method of encoding auxiliary information in an image comprising: computing a change in an attribute of an image sample to encode auxiliary information in the image; and changing color values of the image sample to effect the change in the image sample attribute with minimized impact on visibility; wherein the color values are changed in a direction in color space that depends on original color values of the image sample such that the change in color values is adapted to the color of the image sample and the direction is selected to minimize impact on visibility.
Claim 2
Dependent Claim 101 words
In a watermark encoder, a method of encoding auxiliary information in an image comprising: computing a change in an attribute of an image sample to encode auxiliary information in the image; and changing color values of the image sample to effect the change in the image sample attribute with minimized impact on visibility; wherein the color values are changed in a direction in color space that depends on original color values of the image sample such that the change in color values is adapted to the color of the image sample and the direction is selected to minimize impact on visibility.
Claim 3
Dependent Claim 61 words
The method of claim 1 wherein changing the color values includes transforming the change in the image sample attribute to a change in color components of the image sample such that the change in the color components are selected to minimize visibility of the change in the image sample attribute yet be equivalent to the change in the image sample attribute.
Claim 4
Dependent Claim 31 words
The method of claim 2 including: employing a color look up table to map the change in the image sample attribute to changes in one or more of the color components.
Claim 5
Dependent Claim 18 words
The method of claim 3 where the color components of the image sample comprise CMYK data for printing.
Claim 6
Dependent Claim 37 words
The method of claim 1 including selectively scaling color vectors of image samples to white or black to effect an equivalent change in the luminance of image samples while reducing visibility of the changes to the image.
Claim 7
Dependent Claim 52 words
The method of claim 1 wherein the change in the image sample attribute is a change in magnitude of a specified color vector, and the changes in the color components of the image sample are made to have an equivalent change in the magnitude of the specified color vector while reducing visibility.
Claim 8
Dependent Claim 34 words
The method of claim 1 wherein the change in the image sample attribute is a change in luminance, and the changes in the color components are made to have an equivalent change in luminance.
Claim 9
Dependent Claim 14 words
A computer readable medium having software for performing the method of claim 1 .
Claim 10
Dependent Claim 82 words
In a watermark encoder, a method of encoding auxiliary information in an image comprising: computing a change in an attribute of an image sample to encode auxiliary information in the image; and changing color values of the image sample to effect the change in the image sample attribute with minimized impact on visibility; wherein the change in the image sample attribute is a change in chrominance, and the changes in the color components are made to have an equivalent change in chrominance.
Claim 11
Dependent Claim 82 words
In a watermark encoder, a method of encoding auxiliary information in an image comprising: computing a change in an attribute of an image sample to encode auxiliary information in the image; and changing color values of the image sample to effect the change in the image sample attribute with minimized impact on visibility; wherein the change in the image sample attribute is a change in chrominance, and the changes in the color components are made to have an equivalent change in chrominance.
Claim 12
Dependent Claim 151 words
In a watermark encoder, a method of encoding auxiliary information in an image comprising: computing a change in an attribute of an image sample to encode auxiliary information in the image; and changing color values of the image sample to effect the change in the image sample attribute with minimized impact on visibility; wherein the change in the image sample attribute is a change in a first vector in a color space for a first set of colors, and is a change in a second vector in the color space for a second set of colors; and the change in the image sample attribute is mapped to a change in color components of the image sample to effect the change in the first vector for image samples in the first set of colors, and to effect the change in the second vector for image samples in the second set of colors.
Claim 13
Dependent Claim 151 words
In a watermark encoder, a method of encoding auxiliary information in an image comprising: computing a change in an attribute of an image sample to encode auxiliary information in the image; and changing color values of the image sample to effect the change in the image sample attribute with minimized impact on visibility; wherein the change in the image sample attribute is a change in a first vector in a color space for a first set of colors, and is a change in a second vector in the color space for a second set of colors; and the change in the image sample attribute is mapped to a change in color components of the image sample to effect the change in the first vector for image samples in the first set of colors, and to effect the change in the second vector for image samples in the second set of colors.
Claim 14
Dependent Claim 17 words
The method of claim 10 wherein the first vector represents luminance, and the second vector represents chrominance.
Claim 15
Dependent Claim 31 words
The method of claim 10 wherein image sample attribute corresponds to two or more different vectors in the color space, each of the vectors corresponding to a different set of colors.
Claim 16
Independent Claim 79 words
A method for assessing whether a watermark in an image is valid comprising: decoding a watermark using a color key that indicates how an attribute of an image sample is changed in watermark encoding based on color of the image sample, wherein the color key indicates colors in which the watermark is expected to be embedded, and the colors of watermark embedding vary depending on colors of the image; based on the decoding, determining whether the watermark is valid.
Claim 17
Independent Claim 79 words
A method for assessing whether a watermark in an image is valid comprising: decoding a watermark using a color key that indicates how an attribute of an image sample is changed in watermark encoding based on color of the image sample, wherein the color key indicates colors in which the watermark is expected to be embedded, and the colors of watermark embedding vary depending on colors of the image; based on the decoding, determining whether the watermark is valid.
Claim 18
Dependent Claim 17 words
A computer readable medium on which is stored software for performing the method of claim 13 .
Claim 19
Independent Claim 120 words
A method for assessing whether a watermark in an image is valid comprising: decoding a watermark using a color key that indicates how an attribute of an image sample is changed in watermark encoding based on color of the image sample; based on the decoding, determining whether the watermark is valid; for image samples in the image, using the color key to select a color channel or channels in which the watermark signal is expected to be the strongest; measuring a figure of merit of the watermark signal in the selected color channel or channels; and assessing validity of the watermark signal based on the measured figure of merit of the watermark signal in the selected color channel or channels.
Claim 20
Independent Claim 120 words
A method for assessing whether a watermark in an image is valid comprising: decoding a watermark using a color key that indicates how an attribute of an image sample is changed in watermark encoding based on color of the image sample; based on the decoding, determining whether the watermark is valid; for image samples in the image, using the color key to select a color channel or channels in which the watermark signal is expected to be the strongest; measuring a figure of merit of the watermark signal in the selected color channel or channels; and assessing validity of the watermark signal based on the measured figure of merit of the watermark signal in the selected color channel or channels.
Claim 21
Dependent Claim 20 words
The method of claim 15 wherein the watermark signal is a known watermark signal expected to be in the image.
Claim 22
Dependent Claim 35 words
The method of claim 16 wherein the known watermark signal is a watermark orientation signal having attributes enabling calculation of an orientation of the known watermark signal in an image suspected of containing a watermark.
Claim 23
Independent Claim 79 words
A method for encoding auxiliary data into an image comprising: transforming blocks of the image into transform coefficients; altering the transform coefficients to encode the auxiliary data; determining a characteristic color of the blocks; wherein the transform coefficients are altered such that the auxiliary data is embedded in each block depending on the characteristic color of the block and the auxiliary data is embedded in a selected color that has reduced visibility for the characteristic color of the block.
Claim 24
Independent Claim 79 words
A method for encoding auxiliary data into an image comprising: transforming blocks of the image into transform coefficients; altering the transform coefficients to encode the auxiliary data; determining a characteristic color of the blocks; wherein the transform coefficients are altered such that the auxiliary data is embedded in each block depending on the characteristic color of the block and the auxiliary data is embedded in a selected color that has reduced visibility for the characteristic color of the block.

References Cited (Backward Citations)

US3569619A Cited
US4944036A Cited
US3984624A Cited
US4297729A Cited
US4238849A Cited
US4379947A Cited
US4296326A Cited
US4230990A Cited
US4230990C1 Cited
US4313197A Cited
US4528588A Cited
US4395600A Cited
US4380027A Cited
US4367488A Cited
US4425642A Cited
US4547804A Cited
US4908873A Cited
US4675746A Cited
US4618257A Cited
US4672605A Cited
US4888798A Cited
US4750173A Cited
US5053956A Cited
US4739377A Cited
US4977594A Cited
US4855827A Cited
US5040059A Cited
US4807031A Cited
US4879747A Cited
US5321470A Cited
US5213337A Cited
US4947028B1 Cited
US4947028A Cited
US5146457A Cited
US4969041A Cited
US5023907A Cited
US4908836A Cited
US5095196A Cited
US5216724A Cited
US4972476A Cited
US5181786A Cited
US5521722A Cited
US5062666A Cited
US5817205A Cited
US5790697A Cited
US5790693A Cited
US5905810A Cited
US5719939A Cited
US5103459A Cited
US5103459B1 Cited
US5027401A Cited
US5113445A Cited
US5905248A Cited
US5963916A Cited
US5374976A Cited
US5315098A Cited
US5200822A Cited
US5288976A Cited
US5280537A Cited
US5243423A Cited
US6166750A Cited
US5495581A Cited
US5838458A Cited
US5295203A Cited
US5259025A Cited
US5721788A Cited
US5809160A Cited
US5502576A Cited
US5735547A Cited
US5659164A Cited
US5469222A Cited
US5809317A Cited
US5379345A Cited
US5291243A Cited
US5740244A Cited
US5428731A Cited
US5857038A Cited
US5496071A Cited
US5416307A Cited
EP0642060B1 Cited
US5652626A Cited
US5862260A Cited
US6266430B1 Cited
US5768426A Cited
US5745604A Cited
US5841978A Cited
US5905251A Cited
US5463209A Cited
US5428607A Cited
US5872589A Cited
US5932863A Cited
US5493677A Cited
US5893101A Cited
US5617119A Cited
US5871615A Cited
US5469506A Cited
US5594226A Cited
US5825871A Cited
US5640193A Cited
US5869819A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2006-07-07 2007-01-06 2007-07-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2010-07-07 2011-01-06 2011-07-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2014-07-07 2015-01-06 2015-07-08 $7700.00 Window Closed / Lapsed

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