US4581760A
Expired / Lapsed
US
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Fingerprint verification method
Assignee: Fingermatrix Inc
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Filing: 1983-09-13
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Granted: 1986-04-08
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Expires: 2003-09-13
Abstract
Abstract An input fingerprint image consists of ones and zeros pixels representing light and dark pixels which in turn correspond to ridge and valley formations. This image is compared with a reference file fingerprint to verify the identity of the input fingerprint. The reference file has two relatively small segments which are subfields of the entire field of pixels that constituted the original fingerprint image for the individual involved. Two substantially larger domain subfields are extracted from the input fingerprint image. The center of each segment corresponds to the center of a respective one of the domains. Each segment is scanned over its corresponding domain to determine the position of maximum ones correlation and maximum zeros correlation between each segment and its corresponding domain. These four positions together with the correlation values associated with each of these four positions are subjected to various criteria to provide positive or negative verification of the input image relative to the reference file. These criteria include (a) positional closenes to one another, (b) exclusion of the positions from a predetermined border of the domain, (c) closeness of the correlation values of certain of the positions, and (d) magnitude of the sum of the ones correlations and zeros correlation for certain of the positions.
Inventors
- 👤 Michael Schiller
- 👤 Emmily S. Ginsberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:43
CPC Classifications
G; G07; G07C; G07C9/00; G07C9/30; G07C9/32; G07C9/33; G06; G06V; G06V40/00; G06V40/10; G06V40/12; G06V40/1365; G07C9/37
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
189 words
The method of fingerprint verification by comparison of a reference fingerprint image against an input fingerprint image wherein each image is composed of a field of pixels having first and second values representing respectively fingerprint ridge and valley pixels comprising the steps of: providing at least first and second reference segment images representing subfields from a reference fingerprint, providing at least first and second domain images representing subfields from an input fingerprint, said domain images being substantially larger than said reference segment images, scanning said first reference segment image across said first domain image and scanning said second reference segment image across said second domain image to determine significant positions, said significant positions constituting locations of maximum correlation for each reference segment image/domain image pair between pixels having said first value and also locations of maximum correlation for each reference segment image/domain image pair between pixels having said second value, and verifying the input fingerprint from which said domain images are extracted as corresponding to the reference fingerprint from which said reference segment images are extracted by subjecting at least one of said significant locations to pre-determined positional criteria.
Claim 2
Independent Claim
189 words
The method of fingerprint verification by comparison of a reference fingerprint image against an input fingerprint image wherein each image is composed of a field of pixels having first and second values representing respectively fingerprint ridge and valley pixels comprising the steps of: providing at least first and second reference segment images representing subfields from a reference fingerprint, providing at least first and second domain images representing subfields from an input fingerprint, said domain images being substantially larger than said reference segment images, scanning said first reference segment image across said first domain image and scanning said second reference segment image across said second domain image to determine significant positions, said significant positions constituting locations of maximum correlation for each reference segment image/domain image pair between pixels having said first value and also locations of maximum correlation for each reference segment image/domain image pair between pixels having said second value, and verifying the input fingerprint from which said domain images are extracted as corresponding to the reference fingerprint from which said reference segment images are extracted by subjecting at least one of said significant locations to pre-determined positional criteria.
Claim 3
Dependent Claim
127 words
The method of claim 1 wherein said significant positions include: a first position being the position of said first reference segment image in said first domain image where the maximum correlation is found between pixels having said first value, a second position being the position of said first reference segment image in said first domain image where the maximum correlation is found between pixels having said second value, a third position being the position of said second reference segment image in said second domain image where the maximum correlation is found between pixels having said first value, and, a fourth position being the position or said second reference segment image in said second domain image where the maximum correlation is found between pixels having said second value.
Claim 4
Dependent Claim
44 words
The method of claim 2 wherein: the centers of said first and second reference segment images have substantially the same positional location relative to the reference fingerprint as do the centers of said first and second domain images to the input fingerprint being verified.
Claim 5
Dependent Claim
80 words
The method of claim 2 wherein said step of determining said four significant positions is performed by the steps of: systematically scanning each reference segment image across the corresponding domain image in a series of predetermined overlapping test locations, determining in each test location a score of ones pixel correlation and a score of zeros pixel correlation, and storing for reference the positions of maximum ones pixel correlation and maximum zeros pixel correlation for each reference segment image/domain image pair.
Claim 6
Dependent Claim
38 words
The method of claim 4 wherein said four significant positions are given x and y coordinates in terms of their locations within their respective domain images, said four sets of coordinates being referenced to the same coordinate plane.
Claim 7
Dependent Claim
31 words
The method of claim 5 further comprising the step of: storing for reference the magnitudes of the ones correlation values and the zeros correlation values at each of said four positions.
Claim 8
Dependent Claim
31 words
The method of claim 5 wherein said step of verifying requires that three of said four significant positions be positioned in said coordinate plane within a pre-determined distance of one another.
Claim 9
Dependent Claim
39 words
The method of claim 7 wherein each step of verifying further requires that said three closely associated significant positions be a predetermined distance away from the border of said coordinate plane based on the dimension of said domain images.
Claim 10
Dependent Claim
50 words
The method of claim 7 wherein said step of verifying further requires that said maximum correlation value of said fourth significant position be within a predetermined magnitude or ratio of the correlation value of the same pixel value of the other significant position in the domain of said fourth position.
Claim 11
Dependent Claim
50 words
The method of claim 8 wherein said step of verifying further requires that said maximum correlation value of said fourth significant position be within a predetermined magnitude or ratio of the correlation value of the same pixel value of the other significant position in the domain of said fourth position.
Claim 12
Dependent Claim
63 words
The method of claim 7 wherein said step of verifying further requires that one of said three of said significant positions within said predetermined distance which is in said first domain has a correlation sum that exceed a first threshold and that one of said three significant locations within said predetermined distance that is in said second domain also exceeds said first threshold.
Claim 13
Dependent Claim
63 words
The method of claim 8 wherein said step of verifying further requires that one of said three of said significant positions within said predetermined distance which is in said first domain has a correlation sum that exceed a first threshold and that one of said three significant locations within said predetermined distance that is in said second domain also exceeds said first threshold.
Claim 14
Dependent Claim
63 words
The method of claim 9 wherein said step of verifying further requires that one of said three of said significant positions within said predetermined distance which is in said first domain has a correlation sum that exceed a first threshold and that one of said three significant locations within said predetermined distance that is in said second domain also exceeds said first threshold.
Claim 15
Dependent Claim
63 words
The method of claim 10 wherein said step of verifying further requires that one of said three of said significant positions within said predetermined distance which is in said first domain has a correlation sum that exceed a first threshold and that one of said three significant locations within said predetermined distance that is in said second domain also exceeds said first threshold.
Claim 16
Dependent Claim
37 words
The method of claim 11 where said step of verifying further requires that the correlation value of one of the two positions that exceeds said first threshold also exceeds a second threshold greater than said first threshold.
Claim 17
Dependent Claim
37 words
The method of claim 13 wherein said step of verifying further requires that the correlation value of one of the two positions that exceeds said first threshold also exceeds a second threshold greater than said first threshold.
Claim 18
Dependent Claim
37 words
The method of claim 14 where said step of verifying further requires that the correlation value of one of the two positions that exceeds said first threshold also exceeds a second threshold greater than said first threshold.
Claim 19
Dependent Claim
29 words
The method of claim 1 wherein the subfield of the domain image is approximately an order of magnitude greater in area than the subfield of the reference segment image.
Claim 20
Dependent Claim
29 words
The method of claim 7 wherein the subfield of the domain image is approximately an order of magnitude greater in area than the subfield of the reference segment image.
Claim 21
Dependent Claim
13 words
The method of claim 1 wherein said first and second domain images overlap.
Claim 22
Dependent Claim
13 words
The method of claim 7 wherein said first and second domain image overlap.
Claim 23
Dependent Claim
44 words
The method of claim 4 wherein each of said reference segment image is scanned across the respective domain image in a predetermined pattern and in case of coincident maximum correlation values, the last in sequence is deemed to be one of said significant locations.
Claim 24
Dependent Claim
44 words
The method of claim 7 wherein each of said reference segment images is scanned across the respective domain image in a predetermined pattern and in case of coincident maximum correlation values, the last in sequence is deemed to be one of said significant locations.
Claim 25
Dependent Claim
68 words
The method of claim 1 further comprising the steps of: establishing said reference segment images by first establishing an initial set of reference segment images for a subject finger, then verifying repeated applications of said subject finger in accordance with the method of claim 1, and retaining said initial set in a reference file only if positive verification is obtained in a predetermined number of said repeated applications.
Claim 26
Dependent Claim
67 words
The method of claim 7 further comprising the steps of: establishing said reference segment images by first establishing an initial set of reference segment images for a subject finger, then verifying repeated applications of subject finger in accordance with the method of claim 1, and retaining said initial set in a reference file only if positive verification is obtained in a predetermined number of said repeated applications.
Claim 27
Dependent Claim
62 words
The method of claim 1 further comprising the steps of: applying the steps of claim 1 to verification of first and second input fingerprints taken from different first and second fingers, and providing identification of the subject having said first and second fingerprints if and only if said step of verifying is successfully completed in connection with both of the fingerprint images.
Claim 28
Dependent Claim
62 words
The method of claim 7 further comprising the steps of: applying the steps of claim 7 to verification of first and second input fingerprints taken from different first and second fingers, and providing identification of the subject having said first and second fingerprints if and only if said step of verifying is successfully completed in connection with both of the fingerprint images.
Claim 29
Dependent Claim
40 words
The method of claim 1 further comprising the steps of: applying the steps of claim 1 to separate applications of the subject's input fingerprint, and providing identification if any one of the applications is verified by said step of verifying.
Claim 30
Dependent Claim
40 words
The method of claim 7 further comprising the steps of: applying the steps of claim 1 to separate applications of the subject's input fingerprint, and providing identification if any one of the applications is verified by said step of verifying.
Claim 31
Independent Claim
198 words
The system of verifying an input fingerprint image by comparison of a reference fingerprint image against an input fingerprint image wherein each image is composed of a field of pixels having first and second values representing respectively fingerprint ridge and valley pixels comprising: means to establish at least first and second reference segment images representing subfields from a reference fingerprint, means to establish at least first and second domain images representing subfields from an input fingerprint, said domain images being substantially larger than said reference segment images, scanning means for scanning said first reference segment image across said first domain image and scanning said second reference segment image across said second domain image to determine significant positions, said significant positions constituting locations of maximum correlation for each reference segment image/domain image pair between pixels having said first value and also locations of maximum correlation for each reference segment image/domain image pair between pixels having said second value, and means to verify the input fingerprint from which said domain images are extracted as corresponding to the reference fingerprint from which said reference segment images are extracted by subjecting at least one of said significant locations to pre-determined positional criteria.
Claim 32
Independent Claim
198 words
The system of verifying an input fingerprint image by comparison of a reference fingerprint image against an input fingerprint image wherein each image is composed of a field of pixels having first and second values representing respectively fingerprint ridge and valley pixels comprising: means to establish at least first and second reference segment images representing subfields from a reference fingerprint, means to establish at least first and second domain images representing subfields from an input fingerprint, said domain images being substantially larger than said reference segment images, scanning means for scanning said first reference segment image across said first domain image and scanning said second reference segment image across said second domain image to determine significant positions, said significant positions constituting locations of maximum correlation for each reference segment image/domain image pair between pixels having said first value and also locations of maximum correlation for each reference segment image/domain image pair between pixels having said second value, and means to verify the input fingerprint from which said domain images are extracted as corresponding to the reference fingerprint from which said reference segment images are extracted by subjecting at least one of said significant locations to pre-determined positional criteria.
Claim 33
Dependent Claim
31 words
The combination of claim 30 further comprising: first storage means for storing the maximum ones correlation position and maximum zeros correlation position for each of said reference segment image/domain image pair.
Claim 34
Dependent Claim
27 words
The combination of claim 31 further comprising: second storage means for storing the magnitude of the correlation values for each position stored in said first storage means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-04-07 | 1989-10-07 | 1990-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-04-07 | 1993-10-07 | 1994-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-04-07 | 1997-10-07 | 1998-04-08 | $7700.00 | Window Closed / Lapsed |