1. A mobile communication device for performing touchless fingerprint authentication, comprising: memory for storing a plurality of templates indicative of images of a fingerprint at different depths of field, each of the templates defining feature descriptors for a plurality of key points within one of the images of the fingerprint at a respective depth of field; a camera; and at least one processor programmed to control the camera to capture an image of a fingerprint, the at least one processor further programmed to extract key point data from the captured image by identifying a plurality of key points in the captured image and characterizing each of the plurality of key points in the captured image with a respective feature descriptor that includes a plurality of intensity values for adjacent pixels around the key point being characterized, the at least one processor further programmed to perform comparisons between the feature descriptors characterizing the plurality of key points in the captured image and feature descriptors for each of the templates and to authenticate a user for accessing a resource of the mobile communication device based on the comparisons.