US 7,623,685 B2 · Biometric signatures and identification through the use of projective invariants

Abstract

Techniques, systems and methods for obtaining biometric signatures and identification are described. Broadly stated, embodiments of the present invention utilize specified geometric principles to provide means for accurate biometric identification using projective invariant features of a subregion of the human body. The present invention provides a means for computing biometric signatures and identification that are projective invariant and hence are not impacted by the viewing angle of the subregion of the human body containing the biometric data. This novel invention removes the restriction, often implicit in the previous work, of the imaging or sensing system being in a fixed repeatable (and generally orthogonal) viewing position. This invention can be applied across a wide range of biometrics, although it is most easily applicable to features that are approximately co-planar. A plurality of such projective invariant features can be used to define a biometric signature to either verify an individual's identity, or recognize an individual from a database of already known persons.

Claims17

Dependent claims

A method of generating biometric signatures by a biometric signature system having a processor that executes the following steps, comprising the steps of:

a) capturing an image of a hand;
b) detecting a plurality of image features of a sub-region of the image, wherein the image features are points on creases of fingers of the hand;
c) computing a quasi projective invariant based on a subset of the plurality of image features using cross-ratios, wherein the quasi projective invariant is a property or measurement that is resilient to rotation, translation, uniform scaling, non-uniform scaling, shear and perspective projection;
and
d) determining a similarity between the quasi projective invariant and a stored quasi projective invariant.

2 more elements

Dependencies are inferred from the claim text.

Biometric signatures and identification through the use of projective invariants

Life of this patent

Biometric signatures and identification through the use of projective invariants

Life of this patent

Abstract

Claims17