Information embedding and extraction for electrophotographic printing processes

In today’s digital world securing different forms of content is very important in terms of protecting copyright and verifying authenticity. One example is watermarking of digital audio and images. We believe that a marking scheme analogous to digital watermarking but for documents is very important. In this paper we describe the use of laser amplitude modulation in electrophotographic printers to embed information in a text document. In particular we describe an embedding and detection process which allows the embedding of 1 bit in a single line of text. For a typical 12 point document, 33 bits can be embedded per page.