2. A method comprising: providing at least one computer system; embedding, using the at least one computer system, information into at least one page of a document copy and subsequently detecting whether said information had been embedded into at least one page of a suspect document copy, said document copy being in a rasterized format, herein called a digitized page image, said information being embedded through steps of: providing, using the at least one computer system, the digitized page image having at least one image plane, each said image plane being represented by an image array having brightness data for a plurality of pixels, each of said pixels having at least one color component and having a pixel position; computing, using the at least one computer system, a first set of candidate positions for embedding black speckles into the page image based on said information to be embedded; computing, using the at least one computer system, a second set of candidate positions for embedding ghost speckles into the page image based on said information to be embedded, wherein the second set of candidate positions are white areas of the original document and the ghost speckles are left white and act as a credibility control during subsequent specklemark detection; and embedding, using the at least one computer system, black speckles into the page image at positions where they are not near the edges of the page image's text.
5. The method of claim 2 , the subsequent detection of said information in a suspect page of a document copy being accomplished through steps of: providing a digitized suspect page image having at least one image plane, each said image plane being represented by an image array having brightness data for a plurality of pixels, each of said pixels having at least one color component and having a pixel position; recomputing the first set of candidate positions for embedding speckles into the page image based on said information to be embedded; recomputing the second set of candidate positions for embedding ghost speckles into the page image based on said information to be embedded; geometrically aligning said suspect page image with the page image; determining at each black speckle position whether the suspect page image had a nearby black speckle; computing the number of black speckle positions for which that suspect page image had a black speckle nearby; determining at each ghost speckle position whether the suspect page image had a nearby black speckle; computing the number of ghost speckle positions for which that suspect page image had a black speckle nearby; and determining whether the suspect printed page possessed said information to be embedded.