ENVELOPES AND PRINTED DOCUMENTS EMPLOYING DIGITAL WATERMARKS, AND RELATED METHODS

摘要

Digital watermarks are encoded on envelopes to serve a variety of purposes related to postage (franking), anti-counterfeiting, addressing, and linking to associated internet sites. Digital watermarks can also be formed on blank paper stock so that printed documents formed therewith have desired properties, including the ability to distinguish photocopies from originals, to link to corporate web sites, and to permit document serialization for tracing and other purposes.