Patent US6766045B2 successfully refreshed from Google Patents.
US6766045B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Currency verification
Assignee: Digital Verification Ltd
•
Filing: 2002-03-11
•
Granted: 2004-07-20
•
Expires: 2022-03-11
Abstract
Abstract A method for verifying authenticity of a certificate under test, wherein an authentic version of the certificate has a known watermark in a predetermined watermark region thereof. The method includes capturing an image of at least a portion of the watermark region of the certificate under test. A correlation is found between the image of the watermark region and the known watermark. Responsive to the correlation, a portion of the image of the watermark region is registered with the known watermark, and a range of intensity values in the registered portion of the image is measured. A vector is defined in a decision space, the vector having coordinates given by the range of the intensity values and by a value of the correlation between the image of the watermark region and the known watermark. The certificate under test is determined to be authentic if the vector falls within a predefined area of the decision space.
Inventors
- 👤 Edward Slepyan
- 👤 Alexander Kugel
- 👤 Julia Eisenberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 11:23
CPC Classifications
G; G06; G06T; G06T1/00; G06T1/0021; G06T1/005; G07; G07D; G07D7/00; G07D7/003; G07D7/0034; G06T2201/00; G06T2201/005; G06T2201/0051; G06T2201/0065
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
146 words
A method for verifying authenticity of a certificate under test, wherein an authentic version of the certificate has a known watermark, the method comprising: capturing an image of at least a portion of a predetermined watermark region of the certificate under test; finding a correlation between the image of the watermark region and a template of the known watermark; responsive to the correlation, registering a portion of the image of the watermark region with the template; measuring a range of intensity values in the registered portion of the image; defining a vector in a decision space, the vector having coordinates given by the range of the intensity values and by a value of the correlation between the image of the watermark region and the template; and determining the certificate under test to be authentic if the vector falls within a predefined area of the decision space.
Claim 2
Independent Claim
146 words
A method for verifying authenticity of a certificate under test, wherein an authentic version of the certificate has a known watermark, the method comprising: capturing an image of at least a portion of a predetermined watermark region of the certificate under test; finding a correlation between the image of the watermark region and a template of the known watermark; responsive to the correlation, registering a portion of the image of the watermark region with the template; measuring a range of intensity values in the registered portion of the image; defining a vector in a decision space, the vector having coordinates given by the range of the intensity values and by a value of the correlation between the image of the watermark region and the template; and determining the certificate under test to be authentic if the vector falls within a predefined area of the decision space.
Claim 3
Dependent Claim
25 words
A method according to claim 1 , wherein capturing the image comprises capturing a transmission image by detecting light transmitted through the certificate under test.
Claim 4
Dependent Claim
27 words
A method according to claim 2 , wherein capturing the image further comprises capturing a reflection image by detecting further light reflected from the certificate under test.
Claim 5
Dependent Claim
88 words
A method according to claim 3 , wherein capturing the transmission image comprises illuminating the certificate using a first light source located on a first side of the certificate, and capturing the transmitted light using a detector on a second side of the certificate, opposite the first side, and wherein capturing the reflection image comprises illuminating the certificate using a second light source located on the second side of the certificate, and capturing the reflected light using the same detector that is used to capture the transmitted light.
Claim 6
Dependent Claim
63 words
A method according to claim 1 , wherein capturing the image comprises illuminating the certificate using first and second light source respectively located on opposing first and second sides of the certificate, and receiving light both from the first source transmitted through the certificate and from the second source reflected from the certificate using a detector on the second side of the certificate.
Claim 7
Dependent Claim
36 words
A method according to claim 5 , wherein illuminating the certificate comprises operating the first and second light sources simultaneously, so that the image captured by the detector comprises both the transmitted and the reflected light.
Claim 8
Dependent Claim
41 words
A method according to claim 6 , wherein operating the first and second light sources comprises operating one of the sources substantially continuously and the other of the sources intermittently, while the detector is receiving the transmitted and the reflected light.
Claim 9
Dependent Claim
14 words
A method according to claim 1 , wherein the certificate comprises a currency bill.
Claim 10
Dependent Claim
44 words
A method according to claim 8 , wherein finding the correlation comprises determining a denomination of the bill, and choosing the template with which the correlation is to be found from among a set of templates of such known watermarks, responsive to the denomination.
Claim 11
Dependent Claim
31 words
A method according to claim 9 , wherein finding the correlation further comprises identifying a manufacturer of the bill, and choosing the template from among the set depending on the manufacturer.
Claim 12
Dependent Claim
42 words
A method according to claim 1 , wherein finding the correlation comprises identifying an interfering image element, not belonging to the watermark, in the image of the watermark region, and computing the correlation while excluding the interfering image element from the correlation.
Claim 13
Dependent Claim
32 words
A method according to claim 11 , wherein measuring the range of the intensity values comprises determining the range of the intensity values in the region exclusive of the interfering image element.
Claim 14
Dependent Claim
36 words
A method according to claim 11 , wherein identifying the interfering image element comprises finding pixels in the image of the watermark region having intensity values outside a predetermined range that is associated with the template.
Claim 15
Dependent Claim
34 words
A method according to claim 13 , and comprising counting a number of the pixels whose intensity values are outside the predetermined range, and rejecting the certificate if the number exceeds a predefined threshold.
Claim 16
Dependent Claim
40 words
A method according to claim 13 , and comprising counting a number of the pixels whose intensity values are within the predetermined range, wherein defining the vector comprises defining a further vector coordinate responsive to the number of the pixels.
Claim 17
Dependent Claim
44 words
A method according to claim 1 , wherein defining the vector comprises defining one of the coordinates to be an intensity scaling factor that maps the range of intensity values in the registered portion of the image to the intensity values in the template.
Claim 18
Dependent Claim
190 words
Apparatus for verifying authenticity of a certificate under test, wherein an authentic version of the certificate has a known watermark, the apparatus comprising: an image sensor, which is adapted to capture an image of at least a portion of a predetermined watermark region of the certificate under test and to generate an output signal responsive thereto; and an image processor, coupled to receive the output signal, and adapted to process the signal so as to find a correlation between the image of the watermark region and a template of the known watermark and, responsive to the correlation, to register a portion of the image of the watermark region with the template, the image processor being further adapted to measure a range of intensity values in the registered portion of the image, to define a vector in a decision space, the vector having coordinates given by the range of the intensity values and by a value of the correlation between the image of the watermark region and the template, and to determine the certificate under test to be authentic if the vector falls within a predefined area of the decision space.
Claim 19
Dependent Claim
190 words
Apparatus for verifying authenticity of a certificate under test, wherein an authentic version of the certificate has a known watermark, the apparatus comprising: an image sensor, which is adapted to capture an image of at least a portion of a predetermined watermark region of the certificate under test and to generate an output signal responsive thereto; and an image processor, coupled to receive the output signal, and adapted to process the signal so as to find a correlation between the image of the watermark region and a template of the known watermark and, responsive to the correlation, to register a portion of the image of the watermark region with the template, the image processor being further adapted to measure a range of intensity values in the registered portion of the image, to define a vector in a decision space, the vector having coordinates given by the range of the intensity values and by a value of the correlation between the image of the watermark region and the template, and to determine the certificate under test to be authentic if the vector falls within a predefined area of the decision space.
Claim 20
Dependent Claim
34 words
Apparatus according to claim 17 , wherein the image comprises a transmission image, and wherein the image sensor is arranged to capture the transmission image by detecting light transmitted through the certificate under test.
Claim 21
Dependent Claim
36 words
Apparatus according to claim 18 , wherein the image further comprises a reflection image, and wherein the image sensor is arranged to capture the transmission image by detecting further light reflected from the certificate under test.
Claim 22
Dependent Claim
95 words
Apparatus according to claim 19 , and comprising a first light source located on a first side of the certificate and a second light source located on a second side of the certificate, opposite the first side, both of which light sources are arranged to illuminate the certificate, and wherein the image sensor is located on the second side of the certificate, so as to capture the transmission image while the certificate is illuminated by the first light source, and to capture the reflection image while the certificate is illuminated by the second light source.
Claim 23
Dependent Claim
72 words
Apparatus according to claim 17 , and comprising first and second light sources respectively located on opposing first and second sides of the certificate, both of which light sources are arranged to illuminate the certificate, and wherein the image sensor is located on the second side of the certificate, so as to receive light both from the first source transmitted through the certificate and from the second source reflected from the certificate.
Claim 24
Dependent Claim
33 words
Apparatus according to claim 21 , wherein the first and second light sources are operative simultaneously, so that the image captured by the image sensor comprises both the transmitted and the reflected light.
Claim 25
Dependent Claim
36 words
Apparatus according to claim 22 , wherein one of the sources is operative substantially continuously, while the other of the sources is operative intermittently, while the image sensor is receiving the transmitted and the reflected light.
Claim 26
Dependent Claim
13 words
Apparatus according to claim 17 , wherein the certificate comprises a currency bill.
Claim 27
Dependent Claim
46 words
Apparatus according to claim 24 , wherein the image processor is adapted to determine a denomination of the bill, and to choose the template with which the correlation is to be found from among a set of templates of such known watermarks, responsive to the denomination.
Claim 28
Dependent Claim
33 words
Apparatus according to claim 25 , wherein the image processor is further adapted to identify a manufacturer of the bill, and to choose the template from among the set depending on the manufacturer.
Claim 29
Dependent Claim
44 words
Apparatus according to claim 17 , wherein the image processor is adapted to identify an interfering image element, not belonging to the watermark, in the image of the watermark region, and to compute the correlation while excluding the interfering image element from the correlation.
Claim 30
Dependent Claim
29 words
Apparatus according to claim 27 , wherein the image processor is adapted to determine the range of the intensity values in the region exclusive of the interfering image element.
Claim 31
Dependent Claim
41 words
Apparatus according to claim 27 , wherein the image processor is adapted to identify the interfering image element by finding pixels in the image of the watermark region having intensity values outside a predetermined range that is associated with the template.
Claim 32
Dependent Claim
39 words
Apparatus according to claim 29 , wherein the image processor is adapted to count a number of the pixels whose intensity values are outside the predetermined range, and to reject the certificate if the number exceeds a predefined threshold.
Claim 33
Dependent Claim
43 words
Apparatus according to claim 29 , wherein the image processor is adapted to count a number of the pixels whose intensity values are within the predetermined range, and to define a further coordinate of the vector responsive to the number of the pixels.
Claim 34
Dependent Claim
45 words
Apparatus according to claim 17 , wherein the image processor is adapted to define one of the coordinates to be an intensity scaling factor that maps the range of intensity values in the registered portion of the image to the intensity values in the template.
References Cited (Backward Citations)
US3496370A
Cited
US3683943A
Cited
US3679314A
Cited
US3806710A
Cited
US3782543A
Cited
US3977785A
Cited
US4058194A
Cited
US4296326A
Cited
US4337864A
Cited
US4542829A
Cited
US4553846A
Cited
EP0101115A1
Cited
US4723072A
Cited
US4645936A
Cited
US4881268A
Cited
US5367577A
Cited
US6381354B1
Cited
US5295196A
Cited
US5875259A
Cited
US5467405A
Cited
US5867589A
Cited
US5815592A
Cited
US5790697A
Cited
US5652802A
Cited
US6028951A
Cited
US6241069B1
Cited
WO1993010511A1
Cited
US5533627A
Cited
US5260582A
Cited
US5678863A
Cited
US5483069A
Cited
US6220419B1
Cited
US5607040A
Cited
US5966465A
Cited
US5640463A
Cited
GB2309781A
Cited
WO1996018978A1
Cited
US5854673A
Cited
EP0797815A1
Cited
US5704491A
Cited
US5992601A
Cited
US5938044A
Cited
US5757001A
Cited
US5909502A
Cited
US6026175A
Cited
US5923413A
Cited
US6021883A
Cited
US6012565A
Cited
US6415040B1
Cited
US6104036A
Cited
US6256407B1
Cited
US6060108A
Cited
JP2000113269A
Cited
US6318537B1
Cited
WO2001025127A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2007-07-20 | 2008-01-19 | 2008-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-07-20 | 2012-01-19 | 2012-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-07-20 | 2016-01-19 | 2016-07-20 | $7700.00 | Window Closed / Lapsed |