Fingerprint Ridge Distance Estimation Based on Ridge Search

Fingerprint ridge distance is a very useful parameter in AFIS (automatic fingerprint identification system), it can be used for fingerprint enhancement, identification or classification. In this paper, a new ridge distance estimation method based on the ridge search is presented. Firstly, we use the IPL(initial points line) to select the initial-points line. Then, we follow ridges with the search function to fill the direction window. Finally we compute the ridge distance in the direction window with a transform model. This method estimates ridge distance using the original image directly and does not need the information of ridge direction. Experimental results show that the proposed method can estimate ridge distances effectively.