Method and device for acquiring latent fingerprint orientation

摘要

A method and device for acquiring latent fingerprint orientation. The method includes: extracting a valid area in a latent fingerprint image; acquiring an orientation field of the valid area and a confidence of coordinate points in the valid area; dividing the orientation field into a first area with a high confidence and a second area with a low confidence; collecting control points in the first area, performing triangulation on control points in the first area and determining differences between control points to determine a set of control points; manually marking control points in the second area, adding control points marked to the set, performing triangulation on control points in the set and determining whether a new manually marked control point is to be added in the set according to a difference determination; and establishing a model for control points in the set to obtain an orientation field of the image.

主权项

1. A method for acquiring latent fingerprint orientation, comprising steps of:
A: extracting a valid area in a latent fingerprint image; B: acquiring an orientation field of the valid area and a confidence of each coordinate point in the valid area; C: dividing the orientation field of the valid area into at least one first area with a high confidence and at least one second area with a low confidence by comparing the confidence of each coordinate point with a predefined confidence threshold; D: collecting control points in the at least one first area, performing triangulation to the control points collected in the at least one first area and determining differences between the control points to determine a set of control points; E: manually marking the control points in the at least one second area, adding the control points marked to the set, performing triangulation on all control points in the set and determining whether a new manually marked control point is to be added in the set according to a difference determination; and F: establishing a model for the control points in the set to obtain an orientation field of the latent fingerprint image.