Visible authentication patterns for printed document
First Claim
1. A method of determining whether an analog form of an object is an original analog form, the method comprising the steps of:
- comparing a portion of a digital recording made from the analog form with an original digital representation of the portion to determine a degree of dissimilarity between the recorded portion and the original digital representation of the portion; and
using the degree of dissimilarity to determine whether the analog form is an original analog form.
4 Assignments
0 Petitions
Accused Products
Abstract
Techniques for determining authenticity of analog forms such as packaging or documents (117). One of the techniques determines whether the analog form has been made directly from a digital representation (903) or by photocopying or scanning an analog form. The technique makes the determination by comparing (911) an original digital representation of a portion of the analog form with a digital recording (203) of the portion from the analog form and measuring differences in features that are affected by the operations of photocopying or scanning. The original digital representation (105) and the analog form may have a “noisy”, i.e., random or pseudo random pattern. Such noisy patterns may further be used for other authentication purposes, such as determining whether the portion of the analog form that has the noisy pattern has been altered and to carry hidden messages. The noisy pattern may carry a logo or may be part or all of a barcode.
-
Citations
20 Claims
-
1. A method of determining whether an analog form of an object is an original analog form,
the method comprising the steps of: -
comparing a portion of a digital recording made from the analog form with an original digital representation of the portion to determine a degree of dissimilarity between the recorded portion and the original digital representation of the portion; and
using the degree of dissimilarity to determine whether the analog form is an original analog form. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
-
-
14. A method of performing an authenticity check on an analog form, the method comprising the steps of:
-
comparing a digital recording of a noisy pattern in the analog form and an original digital representation of the noisy pattern; and
using the result of the comparison to perform the authenticity check. - View Dependent Claims (15, 16, 17, 18, 19)
-
-
20. A method of hiding a message in an analog form,
the method comprising the steps of: -
making a digital representation of a perceptible noisy pattern in which the message has been hidden; and
including the noisy pattern in the analog form.
-
Specification