A processor is provided with a first set of digital information that includes a first, resolution-independent structured representation of a document. This first representation is one from which various image collections (e.g., sets of page images) can be obtained, each such image in each such collection...http://www.google.com.au/patents/US5884014?utm_source=gb-gplus-sharePatent US5884014 - Fontless structured document image representations for efficient rendering
