Multiple transform utilization and application for secure digital watermarking

• US 20140226811A1
• Filed: 04/22/2014
• Published: 08/14/2014
• Est. Priority Date: 01/17/1996
• Status: Active Grant

• Current Assignee: Wistaria Trading Inc.
• Original Assignee: Wistaria Trading Inc.
• Inventors: Moskowitz, Scott A.
• Granted Patent: US 9,191,206 B2
• Time in Patent Office: Days
• US Class Current: 380/28
• CPC Class Codes: G06T 1/0028 Adaptive watermarking, e.g. Human Visual System [HVS]-based watermarking
• CPC Class Codes: G06T 1/005 Robust watermarking, e.g. average attack or collusion attack resistant
• CPC Class Codes: G06T 1/0057 Compression invariant watermarking
• CPC Class Codes: G06T 1/0064 Geometric transfor invariant watermarking, e.g. affine transform invariant
• CPC Class Codes: G06T 2201/0051 Embedding of the watermark in the spatial domain
• CPC Class Codes: G06T 2201/0052 Embedding of the watermark in the frequency domain
• CPC Class Codes: G06T 2201/0053 Embedding of the watermark in the coding stream, possibly without decoding; Embedding of the watermark in the compressed domain
• CPC Class Codes: G06T 2201/0061 Embedding of the watermark in each block of the image, e.g. segmented watermarking
• CPC Class Codes: G06T 2201/0063 in relation to collusion attacks, e.g. collusion attack resistant
• CPC Class Codes: G06T 2201/0065 Extraction of an embedded watermark; Reliable detection
• CPC Class Codes: G06T 2201/0083 whereby only watermarked image required at decoder, e.g. source-based, blind, oblivious
• CPC Class Codes: H04L 2209/04 Masking or blinding
• CPC Class Codes: H04L 2209/043 of tables, e.g. lookup, substitution or mapping
• CPC Class Codes: H04L 2209/046 of operations, operands or results of the operations
• CPC Class Codes: H04L 9/0819 Key transport or distribution, i.e. key establishment techniques where one party creates or otherwise obtains a secret value, and securely transfers it to the other(s) network architectures or network communication protocols for key distribution in a packet data network H04L63/062
• CPC Class Codes: H04L 9/14 using a plurality of keys or algorithms
• CPC Class Codes: H04N 1/3216 using Fourier transforms
• CPC Class Codes: H04N 1/32187 with selective or adaptive application of the additional information, e.g. in selected frequency coefficients
• CPC Class Codes: H04N 1/32309 in colour image data
• CPC Class Codes: H04N 2201/3233 of authentication information, e.g. digital signature, watermark
• CPC Class Codes: H04N 2201/324 : Selecting a particular authentication information from amongst a plurality of different authentication information

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.

Claims

1. A method for encoding a message into digital information, the digital information including a plurality of digital blocks, comprising the steps of:

transforming, using a processor, each of the digital blocks, into a frequency domain using a transform function that transforms from time or space to temporal or spatial frequency;

identifying a subset of resulting frequencies using amplitudes associated with the resulting frequencies and a primary mask;

for each one of said digital blocks, selecting from said message, based upon said message and a convolution mask, selected message information and;

encoding, using said processor, the selected message information for each digital block into a corresponding transform of that digital block by altering the amplitudes associated with said subset of resulting frequencies, depending upon a value associated with the corresponding selected message information.

2-60. -60. (canceled)

61. A method of encoding content with message information, comprising:

receiving, in an encoder, data defining content;

said encoder, using a processor and applying a transform function, that transforms from a time or space domain to a temporal or a spatial frequency domain, to a first contiguous subset of said content in the time or space domain, which results in a first transform having first transform values in the frequency domain, and first transform amplitudes associated with said first transform values;

said encoder selecting, based upon said first transform amplitudes, a first transform values first subset of said first transform values;

said encoder using a primary mask and said first transform values first subset to select a first transform values second subset of said first transform values, wherein said first transform values second subset is a subset of said first transform values first subset; and

said encoder manipulating, depending upon the value of a first bit of said message information, the first transform amplitudes associated with said first transform values second subset of said first transform values.

62. The method of claim 61, further comprising:

said encoder applying said transform function, that transforms from a time or a space domain to a temporal or a spatial frequency domain, to a second contiguous subset of said content in the time or space domain, which results in a second transform having second transform values in the frequency domain, and second transform amplitudes associated with said second transform values;

said encoder selecting, based upon said second transform amplitudes, a second transform values first subset of said second transform values;

said encoder using a primary mask and said second transform values first subset to select a second transform values second subset of said second transform values, wherein said second transform values second subset is a subset of said second transform values first subset; and

said encoder manipulating, depending upon the value of a second bit of said message information, the second transform amplitudes associated with said second transform values second subset of said second transform values.

63. The method of claim 61 wherein said encoder comprises a processor and memory for storing data in non transient form, said memory storing said primary mask and said message information, and at least one transform function, and said encoder using said processor in said applying and said manipulating.

64. The method of claim 61 wherein said transform function is a fast Fourier transform.

65. The method of claim 61 wherein said content is one of audio, still image, video, and multimedia.

66. The method of claim 61 wherein said selecting, based upon said first transform amplitudes, selects based upon magnitudes of said first transform amplitudes so that the first transform values first subset are those first transform values having first transfer amplitudes that are larger than first transfer amplitudes associated with first transform values not in said first transform values first subset.

67. The method of claim 61:

wherein said first bit of said message information has either a first logical value or a second logical value; and

wherein said manipulating changes the first transform amplitudes associated with said first transform values second subset if said first bit of said message information has said first logical value, and does not change the first transform amplitudes associated with said first transform values second subset if said first bit of said message information has said second logical value.

68. The method of claim 67, wherein said manipulation is a fractional change to each one of the first transform amplitudes associated with said first transform values second subset, and the fractional change is the same fraction for each one of said first transform amplitudes associated with said first transform values second subset.

69. The method of claim 61, wherein:

said content comprises image data;

said first contiguous subset of said content defines a spatially contiguous two dimensional block of image data; and

said encoder applying said transform function applies said transform function to a color channel of said two dimensional block of image data.

70. The method of claim 61, wherein:

said content comprises image data;

said first contiguous subset of said content defines a spatially contiguous two dimensional block of image data; and

said encoder applying said transform function applies said transform function to said two dimensional block of image data.

71. A system for encoding content with message information, comprising:

a processor; and

memory for storing data in non transient form;

an encoder for encoding said content with said message information;

wherein said memory stores a primary mask, said message information, and at least one transform function;

wherein said encoder is configured to use said processor for applying a transform function to said content and for manipulating said content with said message information;

wherein said encoder is configured to receive data defining said content;

wherein said encoder is configured to apply said transform function, that transforms from a time or a space domain to temporal or spatial frequency domain, to a first contiguous subset of said content in the time or space domain, which results in a first transform having first transform values in the frequency domain, and first transform amplitudes associated with said first transform values;

wherein said encoder is configured to select, based upon said first transform amplitudes, a first transform values first subset of said first transform values;

wherein said encoder is configured to use said primary mask and said first transform values first subset to select a first transform values second subset of said first transform values, wherein said first transform values second subset is a subset of said first transform values first subset; and

said encoder is configured to manipulate, depending upon the value of a first bit of said message information, the first transform amplitudes associated with said first transform values second subset of said first transform values.

72. The system of claim 71:

wherein said encoder is configured to apply said transform function, that transforms from a time or a space domain to a temporal or a spatial frequency domain, to a second contiguous subset of said content in the time or space domain, which results in a second transform having second transform values in the frequency domain, and second transform amplitudes associated with said second transform values;

wherein said encoder is configured to select, based upon said second transform amplitudes, a second transform values first subset of said second transform values;

wherein said encoder is configured to use said primary mask and said second transform values first subset to select a second transform values second subset of said second transform values, wherein said second transform values second subset is a subset of said second transform values first subset; and

wherein said encoder is configured to manipulate, depending upon the value of a second bit of said message information, the second transform amplitudes associated with said second transform values second subset of said second transform values.

73. The system of claim 71 wherein said transform function is a fast Fourier transform.

74. The system of claim 71 wherein said content is one of audio, still image, video, and multimedia.

75. The system of claim 71 wherein said encoder configured to select, based upon said first transform amplitudes, selects based upon magnitudes of said first transform amplitudes so that the first transform values first subset are those first transform values having first transfer amplitudes that are larger than first transfer amplitudes associated with first transform values not in said first transform values first subset.

76. The system of claim 71:

wherein said first bit of said message information has either a first logical value or a second logical value; and

wherein said encoder configured to manipulate, comprises said encoder configured to (1) change the first transform amplitudes associated with said first transform values second subset if said first bit of said message information has said first logical value and (2) to not change the first transform amplitudes associated with said first transform values second subset if said first bit of said message information has said second logical value.

77. The system of claim 76, wherein the manipulation is a fractional change to each one of the first transform amplitudes associated with said first transform values second subset, and the fractional change is the same fraction for each one of said first transform amplitudes associated with said first transform values second subset.

78. The system of claim 71, wherein:

said content comprises image data;

said first contiguous subset of said content defines a spatially contiguous two dimensional block of image data; and

said encoder applying said transform function applies said transform function to a color channel of said two dimensional block of image data.