Method and apparatus for editing and reading edited invisible encodements on media

摘要

A print media has a visible image and a plurality of invisible encodements comprising data printed over it in a hierarchy order, wherein the encodement of the highest order represents a replacement or edited version of the data of lower order encodements. Apparatus and methods provide effectively editing of an existing invisible encodement printed on media with a material sensitive to a first light wavelength by printing an edited or replacement encodement over it with a material sensitive to a second light wavelength of higher order in the hierarchy. Apparatus and methods also provide for selectively reading the highest order encodement, all of the encodements or selected ones of the encodements.