Method and device for the automated authentication of a set of points
AssigneeGemalto SA
InventorClaude Barral
Life of this patent
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Abstract
The invention relates to a method and to an automated device for the authentication of a set of candidate points relative to a set of reference points. The present invention is insensitive to unavoidable translation, rotation and scaling occurring upon successive but independent acquisitions of, for example, of fingerprints.
Claims20
An authentication method implementing a scatter plot, and a set of characteristic points of said scatter plot, said characteristic points being called minutiae, said method including an extraction operation that extracts a signature from the set of characteristic points, wherein said extraction operation includes the operations steps of:
- grouping the minutiae 3 by 3 so as to form non flat triangles having 3 of the minutiae as apexes.
- associating with each selected triangle one ones of the triangles with a piece of information DIAM on the diameter of a corresponding circumscribed circle;
- defining, for each selected triangle, two pieces of angle information, Angle1 and Angle2, respectively representing two ratios involving the three angles of said triangles taken two by two.
An authentication device including at least acquisition means that forms a digitalized bi-dimensional image of a set of characteristic points, said device comprising:
- automatic recognition means for identifying in the bi-dimensional picture, a bi-dimensional distribution of points, each of which corresponds to the location of a minutia;
- calculation means programmed for:
- selecting, from this distribution of points, a plurality of non flat triangles each of which has 3 points of the distribution as apexes,
- associating to each selected triangle a piece of information DIAM on the diameter of the circumscribed circle;
- defining, for each selected triangle, two pieces of information, Angle1 and Angle2, respectively representing two ratios involving the angles of said triangle, taken two by two;
- and
- a non volatile memory for storing, as a representation of said set of characteristic points, a list of triplets formed of at least Diam, Angle1, Angle2 for each selected triangle.
Dependencies are inferred from the claim text.