Patent EP0777197A2 successfully refreshed from Google Patents.
EP0777197A2
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Method for embedding digital information in an image
Assignee: Eastman Kodak Co
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Filing: 1996-11-25
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Granted: —
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Expires: 2016-11-25
Abstract
Abstract A method of embedding digital data in a source image includes the steps of: a) generating a multi-level data image representing the digital data; b) convolving the multi-level data image with an encoding carrier image to produce a frequency dispersed data image; and c) adding the frequency dispersed data image to the source image to produce a source image containing embedded data. The data is recovered from the image by: a) cross correlating the source image containing embedded data with a decoding carrier image to recover the data image; and b) extracting the digital data from the recovered data image. <IMAGE>
Inventors
- 👤 Scott J. Daly
- 👤 John R. Squilla
- 👤 Michel Denber
- 👤 Chris W. Honsinger
- 👤 John Hamilton
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 15:05
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; H04N1/32203; H04N1/32208; H04N1/32251; G06T2201/00; G06T2201/005; G06T2201/0051; G06T2201/0052; G06T2201/0061; G06T2201/0081; G06T2201/0083; H04N2201/00; H04N2201/32; H04N2201/3201; H04N2201/3204; H04N2201/3205; H04N2201/3225; H04N2201/3226; H04N2201/3233; H04N2201/3269; H04N2201/327; H04N2201/328
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
62 words
A method of embedding digital data in a source image, comprising the steps of: a) generating a multi-level data image representing the digital data; b) convolving the multi-level data image with an encoding carrier image to produce a frequency dispersed data image; and c) adding the frequency dispersed data image to the source image to produce a source image containing embedded data.
Claim 2
Dependent Claim
41 words
The method claimed in claim 1, further comprising the steps of: a) cross correlating the source image containing embedded data with a decoding carrier image to recover the data image; and b) extracting the digital data from the recovered data image.
Claim 3
Dependent Claim
76 words
The method claimed in claim 1, wherein the step of generating the multi-level data image, comprises the steps of: a) appending an identification code to the digital data; b) arranging the digital data in a 2-dimensional array; c) generating a multi-level image having data centers representing the bits in the 2-dimensional data array; and d) expanding the multi-level image and filling in the spaces between the data centers with null level values in the multi-level image.
Claim 4
Dependent Claim
19 words
The method claimed in claim 3, further comprising the step of adding error correction bits to the digital data.
Claim 5
Dependent Claim
24 words
The method claimed in claim 3, wherein the data centers are convolved with a shaping kernel to facilitate subsequent detection of the data centers.
Claim 6
Dependent Claim
39 words
The method claimed in claim 1, wherein the encoding carrier image is generated by the steps of: a) providing a 1-dimensional carrier signal; and b) converting the 1-dimensional carrier signal to a 2-dimensional carrier signal using a rotational sweep.
Claim 7
Dependent Claim
78 words
The method claimed in claim 6, wherein the 1-dimensional carrier signal is a linear chirp signal defined by: chirp linear (r) = sin 2π r · f min+ r 2 ·(f max -f min ) 2L , where r is the distance in units of pixels, f min is the minimum frequency of the chirp, f max is the maximum frequency of the chirp, and L is the total length of the chirp in the units of pixels.
Claim 8
Dependent Claim
59 words
The method claimed in claim 6, wherein the 1-dimensional carrier signal is a logarithmic chirp signal defined by: where r is the distance in units of pixels, f min is the minimum frequency of the chirp, f max is the maximum frequency of the chirp, and L is the total length of the chirp in the units of pixels.
Claim 9
Dependent Claim
18 words
The method claimed in claim 2, wherein the decoding carrier image is identical to the encoding carrier image.
Claim 10
Dependent Claim
64 words
The method claimed in claim 2, wherein: a) the decoding carrier image is generated by the steps of: i) providing a 1-dimensional carrier signal, and ii) converting the 1-dimensional carrier signal to a 2-dimensional carrier signal using a rotational sweep; and b) the encoding carrier image is generated similarly by employing a subset of the rotational sweep used to generate the decoder carrier image.
Claim 11
Dependent Claim
16 words
The method claimed in claim 1, wherein the step of convolving employs a periodic 2-D convolution.
Claim 12
Dependent Claim
13 words
The method claimed in claim 1, wherein the adding step is performed optically
Claim 13
Dependent Claim
15 words
The method claimed in claim 2, wherein the steps are performed on a digital computer.
Claim 14
Dependent Claim
26 words
The method claimed in claim 1, further comprising the step of repeating the frequency dispersed data image in a tiled fashion prior to the adding step.
Claim 15
Dependent Claim
37 words
The method claimed in claim 2, further comprising the step of locating a subset of the source image containing embedded data having the lowest high-frequency component variance and cross correlating the subset with the decoding carrier image.
Claim 16
Dependent Claim
15 words
The method claimed in claim 2, wherein the cross correlation step is periodic cross correlation.
Claim 17
Dependent Claim
14 words
An image having embedded digital data produced according to the method of claim 1.
Claim 18
Dependent Claim
16 words
The method claimed in claim 1, wherein the step of adding is performed by optical techniques.
Claim 19
Dependent Claim
38 words
The method claimed in claim 18, wherein the frequency dispersed data image is added to the source image in a photographic printer by placing a transparency having the frequency dispersed image in the film gate of the printer.
Claim 20
Dependent Claim
35 words
The method claimed in claim 18, wherein the frequency dispersed data image is added to the source image in a photographic printer by pre-exposing photographic paper used in the printer with the frequency dispersed image.
Claim 21
Dependent Claim
11 words
A photographic paper having exposed thereon a frequency dispersed data image.
Claim 22
Dependent Claim
35 words
The method claimed in claim 18, wherein the frequency dispersed data image is added to the source image in a photographic camera by pre-exposing photographic film used in the camera with the frequency dispersed image.
Claim 23
Dependent Claim
11 words
A photographic film having exposed thereon a frequency dispersed data image.
Claim 24
Dependent Claim
15 words
The method claimed in claim 6, wherein the 1-dimensional carrier signal is a noise sequence.
Claim 25
Dependent Claim
20 words
The method claimed in claim 6, further comprising the step of applying a tapered weighting function to the carrier signal.
Claim 26
Dependent Claim
28 words
The method claimed in claim 12, wherein the step of adding the frequency dispersed data image to the source image utilizes a scaling factor dependent on film characteristics.
Claim 27
Dependent Claim
20 words
The method claimed in claim 12, wherein the adding step is performed in the film plane of a photographic camera.
Claim 28
Dependent Claim
26 words
The method claimed in claim 12, wherein the adding step is performed by contact exposing a transparency bearing the frequency dispersed data image onto photographic paper.
Claim 29
Dependent Claim
30 words
The method claimed in claim 12, wherein the adding step is performed by simultaneously exposing the source image and the frequency dispersed data image onto photographic paper in photographic printer.
Claim 30
Dependent Claim
26 words
The method claimed in claim 12, wherein the adding step is performed by affixing a transparency bearing the frequency dispersed data image onto the source image.
Claim 31
Dependent Claim
94 words
The method claimed in claim 3, further comprising the steps of: a) cross correlating the source image containing embedded data with a decoding carrier image to recover the data image; and b) extracting the digital data from the recovered data image by: i) converting the recovered data image into a two dimensional data array; ii) periodically tiling the two dimensional data array to produce a tiled two dimensional data array; and iii) searching the tiled two dimensional data array for the identification code to determine the starting location of the two dimensional data array.
Claim 32
Dependent Claim
143 words
The method claimed in claim 2, wherein the recovered data image has rows and columns of values, further comprising the steps of: a) finding the difference between the minimum and maximum values for each row of the recovered data image to produce row difference values; b) finding the difference between the minimum and maximum values for each column of the recovered data image to produce column difference values; c) finding the n highest difference values for the rows and saving the indices of these rows, where n is determined from the size of the multi-level data message; d) finding the n highest difference values for the columns and saving the indices of these columns, where n is determined from the size of the multi-level data message; and e) locating data centers in the recovered data image by intersecting the saved rows and columns.
References Cited (Backward Citations)
US4939515A
Cited
US4972471A
Cited
US5091966A
Cited
US5128525A
Cited
US5168147A
Cited
US5221833A
Cited
US5245165A
Cited
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