Patent US6940993B2 successfully refreshed from Google Patents.
← Back to Patent Explorer
US6940993B2 Expired / Lapsed US ⏱️ 0.0 years remaining

System and method for embedding a watermark signal that contains message data in a digital image

Assignee: Monument Peak Ventures LLC
•
Filing: 2000-12-13
•
Granted: 2005-09-06
•
Expires: 2020-12-13
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A method for embedding a watermark signal that contains message data in a digital image represented as a two-dimensional array of pixel values, includes the steps of: providing a dispersed message image having pixel values representative of the message data; modifying each pixel value of the dispersed message image as a function of the corresponding pixel value in the digital image; and combining the modified dispersed message image with the digital image to produce a watermarked image.

Inventors

  • 👤 Paul W. Jones
  • 👤 Chris W. Honsinger

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 11:02
CPC Classifications
G; G06; G06T; G06T1/00; G06T1/0021; G06T1/0028; G06T2201/00; G06T2201/005; G06T2201/0051

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 131 words
A method for embedding a visually perceptible watermark representing message data in an image having a plurality of pixels to produce a watermarked image, wherein the visually perceptible watermark is perceptible to a human observer when the watermarked image is displayed, but the visually perceptible watermark is not objectionable because the visually perceptible watermark emulates an appearance of noise of an imaging system, comprising the steps of: a) providing a Fourier amplitude spectrum that is representative of the imaging system noise; b) producing a watermark carrier with an Fourier amplitude spectrum that matches the Fourier amplitude spectrum of the imaging system noise; c) producing the visually perceptible watermark using the watermark carrier and the message data; and d) combining the visually perceptible watermark with the image to produce a watermarked image.
Claim 2
Independent Claim 131 words
A method for embedding a visually perceptible watermark representing message data in an image having a plurality of pixels to produce a watermarked image, wherein the visually perceptible watermark is perceptible to a human observer when the watermarked image is displayed, but the visually perceptible watermark is not objectionable because the visually perceptible watermark emulates an appearance of noise of an imaging system, comprising the steps of: a) providing a Fourier amplitude spectrum that is representative of the imaging system noise; b) producing a watermark carrier with an Fourier amplitude spectrum that matches the Fourier amplitude spectrum of the imaging system noise; c) producing the visually perceptible watermark using the watermark carrier and the message data; and d) combining the visually perceptible watermark with the image to produce a watermarked image.
Claim 3
Dependent Claim 30 words
The method of claim 1 , wherein the watermark amplitude for each pixel is proportional to a noise standard deviation that corresponds to a signal level at the pixel location.
Claim 4
Dependent Claim 29 words
The method of claim 1 , further comprising the step of removing existing imaging system noise from the image prior to combining the visually perceptible watermark with the image.
Claim 5
Dependent Claim 16 words
The method of claim 1 , wherein the noise of the imaging system is film grain.
Claim 6
Dependent Claim 38 words
The method of claim 1 , wherein the watermark carrier has a Fourier amplitude spectrum that matches high frequencies of the Fourier amplitude spectrum of the imaging system noise and contains a ramp from zero for low frequencies.
Claim 7
Dependent Claim 30 words
The method of claim 5 further comprising the step of adding low frequency noise to the visually perceptible watermark to match the Fourier amplitude spectrum of the imaging system noise.
Claim 8
Dependent Claim 28 words
The method according to claim 6 further comprising the step of extracting the message data from the watermarked image by correlating the watermarked image with the watermark carrier.
Claim 9
Dependent Claim 28 words
The method according to claim 5 further comprising the step of extracting the message data from the watermarked image by correlating the watermarked image with the watermark carrier.
Claim 10
Dependent Claim 28 words
The method according to claim 1 further comprising the step of extracting the message data from the watermarked image by correlating the watermarked image with the watermark carrier.
Claim 11
Dependent Claim 56 words
The method according to claim 1 further comprising the step of extracting the message data from the watermarked image by correlating the watermarked image with a second carrier having a Fourier amplitude spectrum that matches high frequencies of the Fourier amplitude spectrum of the imaging system noise and contains a ramp from zero for low frequencies.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2008-09-05 2009-03-07 2009-09-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2012-09-05 2013-03-07 2013-09-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2016-09-05 2017-03-07 2017-09-06 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag