| 摘要 |
The invention describes a method for processing printed pages using a contone map (item delta list), which characterises the items on the printed sheet (pictures, graphics, text). The printed pages that are to be processed are formed as compressed, overlap-free contone maps (delta lists), which are generated, using little memory space, by interpreting the page description data (PostScript) of the printed pages. For every pixel on the printed page, the item delta list contains an item-specific identification code, enabling the items on the printed pages to be classified. By using this information when processing each specific item on the printed page (picture replacement, trapping), it is determined which pixels on the printed sheet are to be processed. In this way, a printed sheet can be subsequently processed without changing or interpreting again the original PostScript data. |
