Authenticating identification and security documents and other objects
First Claim
1. A method of digital watermarking a digital image to convey auxiliary data, in which the digital image includes a plurality of line elements, the method comprises:
- determining a dominate angle associated with the line elements; and
in a digital space, and using an electronic processor, varying line angles of at least a set of the plurality of line elements relative to the dominate angle, in which the varying line angles conveys the auxiliary data including a plural-bit message.
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Accused Products
Abstract
The application discloses identification and security documents and methods and systems for authenticating such identification and security documents. In one implementation, a document includes a first surface; and a second surface. The first surface comprises a first set of print structures and a second set of print structures. The first set of print structures and the second set of print structures cooperate to obscure the location on the first surface of the second set of print structures. The second set of print structures is arranged on the first surface so as to provide a reflection pattern. In one example, the reflection pattern includes a diffraction grating. The second set of print structures is preferably provided on the first surface with metallic ink. Of course, other claims and combinations are provided too.
112 Citations
31 Claims
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1. A method of digital watermarking a digital image to convey auxiliary data, in which the digital image includes a plurality of line elements, the method comprises:
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determining a dominate angle associated with the line elements; and in a digital space, and using an electronic processor, varying line angles of at least a set of the plurality of line elements relative to the dominate angle, in which the varying line angles conveys the auxiliary data including a plural-bit message. - View Dependent Claims (4, 6, 7)
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2. A document comprising:
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a first surface; and a second surface, in which the first surface comprises a first set of print structures and a second set of print structures, and in which the first set of print structures and the second set of print structures cooperate to obscure a location on the first surface of the second set of print structures, and in which the second set of print structures are arranged on the first surface so as to provide a reflection pattern. - View Dependent Claims (3, 5, 8, 9, 10, 11, 12, 13, 16, 17, 18, 19)
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14. A method to authenticate a document comprising a first surface and a second surface, in which the first surface comprises a first set of print structures and a second set of print structures, and in which the first set of print structures and the second set of print structures cooperate to obscure a location on the first surface of the second set of print structures, and in which the second set of print structures are arranged on the first surface so as to provide a reflection pattern, said method comprising:
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illuminating the document with energy having a frequency in the range of 50-80 GHz; receiving a reflected pattern from the document; comparing the reflected pattern or attributes of the reflected pattern to an expected pattern or expected attributes; and based at least in part on the comparing, determining whether the document is authentic. - View Dependent Claims (15)
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20. An apparatus comprising:
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an optical imager for capturing image or video data associated with a physical object, the physical object comprising a plurality of randomly or pseudo-randomly occurring features, the physical object further comprising indicia provided thereon, the indicia conveying expected characteristics of the features including expected spatial positioning information relative to the physical object; a display; an electronic processor programmed for; analyzing image or video data captured by the optical imager to obtain actual characteristics of the features, the actual characteristics of the features comprising spatial positioning information for the features on the object; analyzing the image or video data to obtain the expected characteristics of the features; based at least on the expected characteristics and the actual characteristics of the features, providing user feedback via the display corresponding to an expected spatial positioning of the features relative to the object, the user feedback also corresponding to an actual spatial positioning of the features. - View Dependent Claims (21, 22, 23, 24, 25, 26)
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27. A cell phone comprising:
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a camera for capturing image or video data associated with a physical object, the physical object comprising a plurality of randomly or pseudo-randomly occurring features, the physical object further comprising indicia provided thereon, the indicia conveying expected characteristics of the features including expected spatial positioning information relative to the physical object; a display; an electronic processor programmed for; analyzing image or video data captured by the camera to obtain actual characteristics of the features, the actual characteristics of the features comprising spatial positioning information for the features on the object; analyzing the image or video data to obtain the expected characteristics of the features; based at least on the expected characteristics and the actual characteristics of the features, providing user feedback via the display corresponding to an expected spatial positioning of the features relative to the object, the user feedback also corresponding to an actual spatial positioning of the features. - View Dependent Claims (28, 29, 30, 31)
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Specification