Embedding positional-independent hidden data into hardcopy
Ilya V. Kurilin, Ilia V. Safonov, Michael N. Rychagov, Ho‐Keun Lee, Sangho Kim, Don-Chul Choi · Pattern Recognition and Image Analysis · 2011
We propose an approach for embedding of imperceptible hidden data into printed text document with ability to extract this data during scanning. Our approach is based on intrusion of cluster of small black dots (patterns) with predefined positional-independent structure into the document. Such intrusion will not visibly deteriorate document itself. Proposed multiple duplications of embedded information and statistical approach during hidden message extraction provide method with high immunity against document modification or noise.