Vector based topological fingerprint matching
Patent 5631971 Issued on May 20, 1997. Estimated Expiration Date: 
July 15, 2014. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
July 15, 2014. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesFingerprint recognition and retrieval system Identification system employing verification of fingerprints Method and apparatus for matching fingerprints Patent #: 4947442 InventorApplicationNo. 276155 filed on 07/15/1994US Classes:382/125, Extracting minutia such as ridge endings and bifurcations382/209Template matching (e.g., specific devices that determine the best match)ExaminersPrimary: Boudreau, Leo H.Assistant: Tran, Phuoc Attorney, Agent or FirmInternational ClassG06K 009/00AbstractA fingerprint recognition and retrieval system in which the positions of fingerprint minutiae points and an index number for each minutiae point are recorded in a storage medium. The local ridge flow direction in the vicinity of each minutiae point defined by ridge endings and ridge bifurcations is determined and a generating line is projected at an angle to the local ridge flow direction. The generating line has a length sufficient to span a predetermined number of ridges to each side of each of the minutiae points. Each ridge is traced, in two directions, from the point of crossing of the projected generating line along any crossed ridge line. The first occurring topological event is assigned a type code (T) to the topological event. A topological event code vector is generated for each minutiae comprising an ordered sequence of topological type codes encountered during the tracing and any associated minutiae reference numbers and sets of the vectors are stored in a machine searchable database. The matching algorithm systematically develops connected cluster of minutiae points within an unknown one of the fingerprints for which there exists a matching cluster of minutiae points within the fingerprint under comparison and wherein the topological relationships among the set of minutiae within the matching clusters are substantially identical.Other References
Field of SearchUsing a fingerprintExtracting minutia such as ridge endings and bifurcations With a guiding mechanism for positioning finger With a prism Directional codes and vectors (e.g., Freeman chains, compasslike codes) Line thinning or thickening Skeletonizing Template matching (e.g., specific devices that determine the best match) Image storage or retrieval | |
