Patent Document ID: 20120300988
Application ID: 13480122
Patent Status: 0

Claim One:
1. A method for authenticating scanners, including fingerprint area scanners, said method comprising: using an electronic processing circuit configured to perform the following, (a) acquiring at least one enrolled image for comparison to at least one query image subsequently input to said scanner; (b) decomposing said at least one enrolled image and said at least one query image using wavelets to, respectively, compute enrolled wavelet coefficients and query wavelet coefficients; (c) performing wavelet reconstruction by, respectively, setting to zero at least the LL-subband coefficients of said enrolled wavelet coefficients to compute enrolled residuals and at least the LL-subband coefficients of said query wavelet coefficients to compute query residuals; (d) masking useful pixels of said enrolled residuals and said query residuals; (e) computing a similarity score between common pixels of said useful pixels from said enrolled residuals and said query residuals; and (f) comparing said similarity score with a threshold value to determine whether said at least one query image inputted to the scanner was acquired by the same scanner that acquired said at least one enrolled image.