Patent Document ID: 20030169899
Application ID: 10094941
Patent Status: 0

Claim One:
1. A method for verifying authenticity of a certificate under test, wherein an authentic version of the certificate has a known watermark in a predetermined watermark region thereof, the method comprising: capturing an image of at least a portion of the watermark region of the certificate under test; finding a correlation between the image of the watermark region and the known watermark; responsive to the correlation, registering a portion of the image of the watermark region with the known watermark; measuring a range of intensity values in the registered portion of the image; defining a vector in a decision space, the vector having coordinates given by the range of the intensity values and by a value of the correlation between the image of the watermark region and the known watermark; and determining the certificate under test to be authentic if the vector falls within a predefined area of the decision space.