US 11,954,931 B1
Methods and systems for detecting tampering of an IR security mark
Rajasekar Kanagasabai, Chennai (IN); Haripriya Chandran, Kulathur Chal (IN); Vignesh Doss, Palanichettipatti (IN); and Sainarayanan Gopalakrishnan, Chennai (IN)
Assigned to Xerox Corporation, Norwalk, CT (US)
Filed by XEROX CORPORATION, Norwalk, CT (US)
Filed on Oct. 4, 2022, as Appl. No. 17/937,794.
Int. Cl. G06K 9/00 (2022.01); G06V 10/28 (2022.01); G06V 20/00 (2022.01); G06V 30/413 (2022.01); G06V 30/414 (2022.01); G06V 30/418 (2022.01)
CPC G06V 30/413 (2022.01) [G06V 10/28 (2022.01); G06V 20/95 (2022.01); G06V 30/414 (2022.01); G06V 30/418 (2022.01); G06V 2201/13 (2022.01)] 20 Claims
OG exemplary drawing
 
1. A method for detecting a tampered infrared (IR) security mark in documents, the method comprising:
receiving a document comprising the IR security mark, wherein the IR security mark further comprises one or more security texts and/or images;
scanning the document to generate scanned data;
segmenting a portion of the scanned data comprising the IR security mark into a plurality of blocks;
calculating a ratio of white to black pixels for each block;
comparing the calculated ratio with a known threshold for each block; and
upon comparison, detecting the IR security mark as a tampered security mark.