Abstract: A method for automatic fingerprint classification is dependent on the number of core points and the ridge flow direction around the core points. The speed of the classification process is improved by pre-processing the fingerprint image to identify the background blocks and the fingerprint blocks, so that the process only deal with the fingerprint blocks. A block directional image is constructed for the fingerprint blocks. The block directional image is then used to determine the core point(s) of the fingerprint. Based on the number of core point and the trend of the ridge direction around each core point, fingerprints can be classified into 8 classes based on a set of predetermined rules.

Abstract: A fingerprint recognizing apparatus includes: a prism, an electroluminescent device secured or adhered on an incident surface of the prism for emitting a uniform light towards a finger-laying surface of the prism with the light beam reflected at the valleys of the fingerprint, a photosensor selected from a charge-coupled-device (CCD) sensing camera for picking up the image as reflected from the prism for converting the image signal to be a voltage signal, and an image processing and recognizing circuit for processing the voltage signal for fingerprint identification, wherein the energizing of the ELD is synchronized with the image processing and recognizing for a reliable fingerprint recognization.