Patent ID: 6086706
Filing Date: 2000-07-11
Classification: G03G,G07D,G07F,H04N,Y10S

Abstract:
A method of deterring illicit copying of electronically published documents, which comprises:(a) utilizing a computer system to electronically publish a plurality of copies of a document having electronically created material thereon for distribution to a plurality of subscribers;(b) operating programming within said computer system so as to perform the following steps:(i) encoding said plurality of copies each with a separate, unique identification code, said identification code being based on a unique arrangement of the electronically created material on each such copy based on line-shift coding, wherein said line-shift coding includes altering a bitmap image of the document to shift locations of at least one line of text relative to other lines of text contained in the document to uniquely encode each copy of the document; and(ii) creating a codebook of a plurality of identification codes to correlate each such identification code to a particular subscriber, whereby illicit copies of a document can be traced to the particular subscriber associated with the identification code within the document.