US 9,390,345 B2
Means for using microstructure of materials surface as a unique identifier
Celine Di Venuto Dayer, V, Les Paccots (CH); Martin Kutter, Remaufens (CH); and Frederic Jordan, Les Paccots (CH)
Assigned to ALPVISION S.A., Vevey (CH)
Filed by ALPVISION, S.A., Vevey (CH)
Filed on Dec. 4, 2015, as Appl. No. 14/959,803.
Application 14/959,803 is a continuation of application No. 13/471,185, filed on May 14, 2012, granted, now 9,208,394.
Application 13/471,185 is a continuation in part of application No. 12/041,790, filed on Mar. 4, 2008, granted, now 8,180,174, issued on May 15, 2012.
Application 12/041,790 is a continuation in part of application No. PCT/EP2006/066043, filed on Sep. 5, 2006.
Claims priority of application No. 05108123 (EP), filed on Sep. 5, 2005.
Prior Publication US 2016/0140420 A1, May 19, 2016
Int. Cl. G06K 9/00 (2006.01); G06K 9/62 (2006.01); H04N 5/225 (2006.01); G06K 9/46 (2006.01); G06K 9/68 (2006.01); G06K 9/78 (2006.01)
CPC G06K 9/6204 (2013.01) [G06K 9/00093 (2013.01); G06K 9/00577 (2013.01); G06K 9/4604 (2013.01); G06K 9/6857 (2013.01); G06K 9/78 (2013.01); H04N 5/2256 (2013.01); G06K 2009/6213 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method to authenticate a product comprising a parameter settings phase, an acquisition phase and an identification phase;
the parameter setting phase comprising:
selecting an imaging lighting orientation, an imaging resolution and a region of interest on the reference product surface;
the acquisition phase comprising the steps of:
lighting, with an imaging device, the surface of a first reference product item with the imaging lighting orientation;
capturing, with the imaging device, an image of a microstructure of the region of interest on the reference product surface, wherein the image has sufficient resolution to show a least one product surface microstructure feature at the pixel level;
computing, with the imaging device, an image feature to characterize the captured image; and
storing, with the imaging device, the image feature in a database;
the identification phase comprising the steps of:
lighting, with an imaging device, the surface of a product to authenticate with the imaging lighting orientation;
capturing, with the imaging device, an image of a microstructure of the region of interest on the surface of the product to authenticate, wherein the image has sufficient resolution to show a least one microstructure feature at the pixel level;
computing, with the imaging device, an initial image feature to characterize the captured image of the region of interest on the surface of the product to authenticate;
querying, with the imaging device, for a reference product item, a reference image feature in the database;
comparing the initial image feature and the reference image feature, with an image matching technique;
responsive to the comparison, computing, with the imaging device, a refined image feature to characterize the captured image;
measuring a correlation metric between the refined image feature and the reference image feature; and
identifying a match between the product to authenticate and the reference product item when the correlation metric is above a predefined threshold.