Patent ID: 8873818

Claim:
A method of generating characteristic curves, wherein the characteristic curves are representative of ridges in an image, the method comprising: generating a gradient magnitude image and gradient vector data based at least in part upon the image, the gradient magnitude image comprising a plurality of points, the plurality of points comprising a set of points having respective non-zero intensities; identifying from amongst the set of points a plurality of seed points, the plurality of seed points being a predefined percentage of highest intensity points in the set of points; and building characteristic curves, wherein building each characteristic curve comprises; identifying, from amongst the plurality of seed points, a highest intensity seed point not yet associated with a characteristic curve selecting as a selected point, a first curve point based at least in part upon the identified seed point; examining points at least one unit orthogonal to a gradient vector of the selected point; selecting a subsequent point based at least in part upon the examining of the points; and determining whether an indication of a terminating event has been received; when the indication has not been received, iterating the examining of points, the selecting of a subsequent point and the determining, wherein the subsequent point of an iteration is the selected point of a subsequent iteration; and when the indication has been received, recording the characteristic curve based at least in part upon the selected points.