Patent ID: 11954931
Assignee: XEROX CORPORATION
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 16:
17. A method for detecting tampering of an infrared (IR) security mark in a document, 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 in a RGB format;
converting the scanned data from the RGB format to a binary format;
segmenting a portion of the scanned data in the binary format, 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 to classify the block either as a tampered block or a non-tampered block; and
comparing the number of tampered blocks with the number of non-tampered blocks to confirm whether the IR security mark is tampered or not.