Abstract: Methods and apparatus include scaling imaging of an electrophotographic (EP) device, such as a laser printer or copy machine, to obtain various media output speeds (in pages per minute). A scanning unit has a substantially fixed scan rate during printing and reflects a laser beam onto a photoconductor to create a latent image at a first resolution. A media is advanced into contact with the latent image at a predetermined printing process speed to obtain a printed image output of the latent image at a size corresponding to a size (job resolution) of the image input data, but at a resolution different than the resolution of the image data input. A controller alters data used to create the latent image. Techniques for altering resolution include processing relative to a raster image processor to stretch one resolution dimension of the bitmap into a larger resolution dimension.

Abstract: Methods and systems for estimating single or multi-colored toner coverage on a printed page. One method includes generating color plane bitmaps corresponding to each color in a contone bitmap and calculating pixel coverage values for each of the color plane contone bitmaps. Another method includes receiving image data to be printed, generating color separations for the image data corresponding to available toner colors, printing each color separation on a printed page, scanning each printed page comprising the color separation and calculating toner coverage on each of the scanned printed pages.

Abstract: The present invention is directed a method of color trapping. In one embodiment, the color trapping is performed during the rasterization process. The color trapping comprises identifying page objects into a variety of different categories. Color trapping for each of the page objects is then performed based on specific procedures for the category. In one embodiment, the categories include identifying the page objects as rectangles, characters, and non-rectangular shapes. In one embodiment, specific page objects may be identified as being of a type that color trapping is not to be performed.

Abstract: The present invention is directed a method of color trapping. In one embodiment, the color trapping is performed during the rasterization process. The color trapping comprises identifying page objects into a variety of different categories. Color trapping for each of the page objects is then performed based on specific procedures for the category. In one embodiment, the categories include identifying the page objects as rectangles, characters, and non-rectangular shapes. In one embodiment, specific page objects may be identified as being of a type that color trapping is not to be performed.

Abstract: A print quality enhancement arrangement for a dot matrix printer such as a thermal ink jet printer. The arrangement includes a buffer for receiving 300 dots per inch (dpi) resolution data in the horizontal (print head movement) direction and creates 600 dpi resolution data using image enhancement techniques. The arrangement further includes correction of the higher resolution data to remove pels which are unprintable due to the frequency response of the print elements in the print head. The correction is performed using knowledge of the history of printed pels and the original 300 dpi data. The creation of the higher resolution data and its correction occur "on-the-fly" as data is being fed to the print head, rather than through the creation of a 300 by 600 dpi bitmap.