1. A method for embedding human readable information in images, said method comprising the steps of inputting tone value data defining an image including human readable information to a halftone generator for embedding said information in a halftone pattern, said halftone pattern being composed of halftone half tone cells, with each of said cells containing a fill pattern that is symmetrical about a central axis of the cell; and selectively modulating the tone value of selected portions of said data for visually offsetting said human readable information from non-human readable portions of said image.