| 摘要 |
Techniques and apparatuses for detecting false accepts in biometric authentication systems are provided. According to an aspect of the invention, a sequence of threshold tests are performed on measured biological data after it is compared to valid stored data. According to one embodiment, the threshold tests comprise a distance test (612), a rotational angle test (616), and, optionally, an alternate rotation angle test (636). In a fingerprint sensing environment, the distance test (612) examines the separation between selected minutiae in a measured fingerprint and corresponding minutiae in a stored constellation (300). In the rotational angle test (616), a total angle difference between selected minutiae in the measured fingerprint and corresponding minutiae in the stored constellation (300) is examined. In the alternate rotation angle test (636), a Gestalt rotational difference between selected minutiae in the measured fingerprint and in the stored constellation (300) is calculated. Thus, two independent calculations of the rotation angle between the sensed and valid constellations can be reconciled. In each of the tests, threshold parameters provide a cutoff for rejecting one or more matched minutia that are actually "false accepts". |
