Image analysis – Histogram processing – For setting a threshold
Patent
1986-12-18
1989-02-14
Boudreau, Leo H.
Image analysis
Histogram processing
For setting a threshold
382 52, G06K 900
Patent
active
048052230
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
This invention relates to a method for establishing the authenticity of a person presenting oneself to a recognition station. The invention relies on an arrangement for capturing a skin-pattern which is unique to the person in question (e.g. a toe, finger or palm print) and presenting this in digital form so that it can be compared with a memory-stored digitised skin pattern characteristic of the person.
The invention is expected to find applications in a number of different areas. An important one is to verify the identity of a person presenting a credit or bankers card at a point-of-sale location.
Alternatively a skin-pattern authentication method according to the invention can form the basis for an electronic lock, limiting access to a secure location only to individuals authorised to enjoy such access.
A skin-pattern authentication method according to the invention can form the basis for an identity confirmation device to enable secure computer and information access at isolated stations in an electronic or optical network
Discussion of Prior Art
The objective of individual recognition by fingerprints is not unique to this invention. Other approaches have been disclosed in GB-A-1509095, GB-A-1583386, US-A-4015240 and US-A-4310827 and in published literature. Those most frequently cited involve a preliminary analysis of the image to determine the location of minutiae identified with ridge endings, bifurcations, etc.. The pattern of the minutiae is then matched against a reference pattern. The process described in this specification is not related to these forms of recognition; it is not based on any special analysis or property of the minutiae.
The use of a prism to reveal the image of a fingerprint is not unique to this invention (see for example U.S. Pat. No. 4,015,240).
SUMMARY OF THE INVENTION
According to one aspect of the invention, a method of authenticating a person by comparing information from a currently taken skin-pattern with stored information from a previously taken skin-pattern is characterised in that the currently taken skin-pattern is produced on a contact surface, an image of the print of the skin pattern on the contact surface is projected onto a photodetector device, the intensity variations of the print image in at least one region thereof impinging on the photo-detector device is assessed in digital form in a multiplicity of different sub-regions of the or each said region to create a first digital signal train, a second digital signal train is derived from the stored skin pattern information and the first and second signal trains are compared to determine the degree of coincidence therebetween, an assessment of the determined degree being used to decide whether the currently-taken and stored skin patterns are sufficiently similar to authenticate the person.
The process of direct correlation which is utilised in the carrying out of the method of this invention, is conventionally discarded as impractical on the grounds of image variation and distortion. The method disclosed here overcomes the difficulties associated with direct correlation and offers a unique practical solution for speedy and economical recognition hardware.
Suitably the image of the skin pattern is created by making the contact surface, the hypotenuse face of a right angled prism and projecting an image of this pattern-contacted face onto a surface of the photodetector device which is divided into a multiplicity of separate photon-sensitive areas, each representing one pixel of the projected image.
Preferably the degree of coincidence between the first and second signal trains is assessed on the basis of direct correlation and desirably by direct binary correlation.
Conveniently the direct correlation is effected using, as the stored information, a reference template representing less than 10% of the full image of the currently-taken skin pattern.
Suitably only determinate samples of the image which can clearly be categorised as a binary "1" or a binary "0" are used for the correlation, all
REFERENCES:
patent: 3200701 (1965-08-01), White
patent: 3944978 (1976-03-01), Jensen
patent: 3975711 (1976-08-01), McMahon
patent: 4015240 (1977-03-01), Swonger et al.
patent: 4151512 (1979-04-01), Riganati et al.
patent: 4186378 (1980-01-01), Moulton
patent: 4210899 (1980-07-01), Swonger
patent: 4246568 (1981-01-01), Peterson
patent: 4310827 (1982-01-01), Asai
patent: 4322163 (1982-03-01), Schiller
patent: 4414684 (1983-11-01), Blonder
patent: 4468809 (1984-08-01), Grabowski et al.
patent: 4581760 (1986-04-01), Schiller et al.
patent: 4618988 (1986-10-01), Schiller
patent: 4641350 (1987-02-01), Bunn
Deerhake et al., "Fingerprint Verification Method", IBM Tech. Disclosure Bull., vol. 18, No. 3, Aug. 1975, pp. 888-889.
IBM TDB, (vol. 17, No. 12, May 1975).
Boudreau Leo H.
Free Albert L.
The Quantum Fund Limited
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