Printed page tag encoder

Abstract

A tag encoder for producing tags to be incorporated into a printed page is disclosed. The tag encoder has an input to receive a tag structure template, an input to receive fixed data bits, an input to receive variable data bit records and a tag generator outputting single bits depending on the position in the tag defined by the tag structure template and the fixed and variable data bits. The encoder has a redundancy encoder which utilizes Reed-Solomon encoding. The tag encoder is present in a printer. In addition to the tag encoder, the printer has a contone image decoder to decode compressed continuous tone image planes and a bi-level decoder to decode any compressed bi-level image plane in the compressed data. These decoded image planes are combined with the output of the tag encoder in a halftoner/compositor to produce a printed page carrying tagged areas. The tags are printed in ink which is invisible to the human eye. Such inks, could be IR or UV absorptive.

Dependencies are inferred from the claim text.