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US6205249B1 Expired / Lapsed US ⏱️ 0.0 years remaining

Multiple transform utilization and applications for secure digital watermarking

Assignee: Wistaria Trading Ltd
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Filing: 1998-04-02
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Granted: 2001-03-20
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Expires: 2018-04-02
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Abstract

Abstract Multiple transform utilization and applications for secure digital watermarking. In one embodiment of the present invention, digital blocks in digital information to be protected are transformed into the frequency domain using a fast Fourier transform. A plurality of frequencies and associated amplitudes are identified for each of the transformed digital blocks and a subset of the identified amplitudes is selected for each of the digital blocks using a primary mask from a key. Message information is selected from a message using a transformation table generated with a convolution mask. The chosen message information is encoded into each of the transformed digital blocks by altering the selected amplitudes based on the selected message information.

Inventors

  • 👤 Scott A. Moskowitz

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 11:52
CPC Classifications
G; G06; G06T; G06T1/00; G06T1/0021; G06T1/0028; H; H04; H04L; H04L9/00; H04L9/14; G06T1/005; G06T1/0057; G06T1/0064; H04L9/08; H04L9/0816; H04L9/0819; H04N; H04N1/00; H04N1/32; H04N1/32101; H04N1/32144; H04N1/32149; H04N1/32154; H04N1/3216; H04N1/32187; H04N1/32309; G06T2201/00; G06T2201/005; G06T2201/0051; G06T2201/0052; G06T2201/0053; G06T2201/0061; G06T2201/0063; G06T2201/0065; G06T2201/0083; H04L2209/00; H04L2209/04; H04L2209/043; H04L2209/046; H04N2201/00; H04N2201/32; H04N2201/3201; H04N2201/3225; H04N2201/3233; H04N2201/324

Claims Analysis

Total Claims: 25
Claim 1
Independent Claim 111 words
A method for encoding a message into digital information, the digital information including a plurality of digital blocks, comprising the steps of: transforming each of the digital blocks into the frequency domain using a fast Fourier transform; identifying a plurality of frequencies and associated amplitudes for each of the transformed digital blocks; selecting a subset of the identified amplitudes for each of the digital blocks using a primary mask from a key; choosing message information from the message using a transformation table generated with a convolution mask; and encoding the chosen message information into each of said transformed digital blocks by altering the selected amplitudes based on the chosen message information.
Claim 2
Independent Claim 111 words
A method for encoding a message into digital information, the digital information including a plurality of digital blocks, comprising the steps of: transforming each of the digital blocks into the frequency domain using a fast Fourier transform; identifying a plurality of frequencies and associated amplitudes for each of the transformed digital blocks; selecting a subset of the identified amplitudes for each of the digital blocks using a primary mask from a key; choosing message information from the message using a transformation table generated with a convolution mask; and encoding the chosen message information into each of said transformed digital blocks by altering the selected amplitudes based on the chosen message information.
Claim 3
Dependent Claim 37 words
The method of claim 1 , wherein the digital information contains pixels in a plurality of color channels forming an image, and each of the digital blocks represents a pixel region in one of the color channels.
Claim 4
Dependent Claim 29 words
The method of claim 1 , wherein said step of identifying comprises: identifying a predetermined number of amplitudes having the largest values for each of the transformed digital blocks.
Claim 5
Dependent Claim 64 words
The method of claim 1 , wherein the chosen message information is a message bit and wherein said step of encoding comprises the step of: encoding the chosen message bit into each of said transformed digital blocks by reducing the selected amplitudes using a strength fraction if the message bit is true, and not reducing the selected amplitudes if the message bit is false.
Claim 6
Dependent Claim 13 words
The method of claim 4 , wherein the strength fraction is user defined.
Claim 7
Dependent Claim 23 words
The method of claim 1 , further comprising the step of storing each of the selected amplitudes and associated frequencies in the key.
Claim 8
Dependent Claim 24 words
The method of claim 6 , wherein the image is a rectangle and the reference subset of pixels form a diagonal of the rectangle.
Claim 9
Dependent Claim 22 words
The method of claim 7 , wherein said steps of padding and re-comparing are performed until a satisfactory fit value is obtained.
Claim 10
Dependent Claim 22 words
The method of claim 1 , further comprising the step of storing a reference subset of the digital information into the key.
Claim 11
Dependent Claim 40 words
The method of claim 1 , wherein the digital information contains pixels forming an image, further comprising the steps of: saving a reference subset of the pixels in the key; and storing original dimensions of the image in the key.
Claim 12
Dependent Claim 20 words
The method of claim 10 , wherein the reference subset of pixels form a line of pixels in the image.
Claim 13
Dependent Claim 21 words
The method of claim 1 , further comprising the step of: requiring a predetermined key to decode the encoded message information.
Claim 14
Dependent Claim 22 words
The method of claim 1 , further comprising the step of: requiring a public key pair to decode the encoded message information.
Claim 15
Dependent Claim 28 words
The method of claim 1 , further comprising the steps of: calculating an original hash value for the message; and storing the original hash value in the key.
Claim 16
Independent Claim 110 words
A method for encoding a message into digital information, the digital information including a plurality of digital blocks, comprising the steps of: transforming each of the digital blocks into the frequency domain using a spectral transform; identifying a plurality of frequencies and associated amplitudes for each of the transformed digital blocks; selecting a subset of the identified amplitudes for each of the digital blocks using a primary mask from a key; choosing message information from the message using a transformation table generated with a convolution mask; and encoding the chosen message information into each of said transformed digital blocks by altering the selected amplitudes based on the chosen message information.
Claim 17
Independent Claim 110 words
A method for encoding a message into digital information, the digital information including a plurality of digital blocks, comprising the steps of: transforming each of the digital blocks into the frequency domain using a spectral transform; identifying a plurality of frequencies and associated amplitudes for each of the transformed digital blocks; selecting a subset of the identified amplitudes for each of the digital blocks using a primary mask from a key; choosing message information from the message using a transformation table generated with a convolution mask; and encoding the chosen message information into each of said transformed digital blocks by altering the selected amplitudes based on the chosen message information.
Claim 18
Dependent Claim 13 words
The method of claim 15 , wherein the digital information contains audio information.
Claim 19
Dependent Claim 39 words
The method of claim 15 , wherein the digital information contains audio information, further comprising the steps of: saving a reference subset of audio information in the key; and storing original dimensions of the audio signal in the key.
Claim 20
Dependent Claim 17 words
The method of claim 17 , wherein the reference subset of audio information includes an amplitude setting.
Claim 21
Independent Claim 121 words
A method of extracting a message from encoded digital information using a predetermined key, comprising the steps of: decoding the encoded digital information into digital information, including a plurality of digital blocks, using the predetermined key; transforming each of the digital blocks into the frequency domain using a fast Fourier transform; identifying a plurality of frequencies and associated amplitudes for each of the transformed digital blocks; selecting a subset of the identified amplitudes for each of the transformed digital blocks using a primary mask from the key; comparing the selected amplitudes with original amplitudes stored in the predetermined key to determine the position of encoded message information; and assembling the message using the encoded message information and a reverse transformation table.
Claim 22
Independent Claim 121 words
A method of extracting a message from encoded digital information using a predetermined key, comprising the steps of: decoding the encoded digital information into digital information, including a plurality of digital blocks, using the predetermined key; transforming each of the digital blocks into the frequency domain using a fast Fourier transform; identifying a plurality of frequencies and associated amplitudes for each of the transformed digital blocks; selecting a subset of the identified amplitudes for each of the transformed digital blocks using a primary mask from the key; comparing the selected amplitudes with original amplitudes stored in the predetermined key to determine the position of encoded message information; and assembling the message using the encoded message information and a reverse transformation table.
Claim 23
Dependent Claim 34 words
The method of claim 19 , further comprising the steps of: calculating a hash value for the assembled message; and comparing the calculated hash value with an original hash value in the predetermined key.
Claim 24
Independent Claim 120 words
A method of extracting a message from encoded digital information using a predetermined key, comprising the steps of: decoding the encoded digital information into digital information, including a plurality of digital blocks, using the predetermined key; transforming each of the digital blocks into the frequency domain using a spectral transform; identifying a plurality of frequencies and associated amplitudes for each of the transformed digital blocks; selecting a subset of the identified amplitudes for each of the transformed digital blocks using a primary mask from the key; comparing the selected amplitudes with original amplitudes stored in the predetermined key to determine the position of encoded message information; and assembling the message using the encoded message information and a reverse transformation table.
Claim 25
Independent Claim 120 words
A method of extracting a message from encoded digital information using a predetermined key, comprising the steps of: decoding the encoded digital information into digital information, including a plurality of digital blocks, using the predetermined key; transforming each of the digital blocks into the frequency domain using a spectral transform; identifying a plurality of frequencies and associated amplitudes for each of the transformed digital blocks; selecting a subset of the identified amplitudes for each of the transformed digital blocks using a primary mask from the key; comparing the selected amplitudes with original amplitudes stored in the predetermined key to determine the position of encoded message information; and assembling the message using the encoded message information and a reverse transformation table.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2004-03-19 2004-09-18 2005-03-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2008-03-19 2008-09-18 2009-03-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2012-03-19 2012-09-18 2013-03-20 $7700.00 Window Closed / Lapsed

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