Abstract: A print engine includes a printer module for printing image data in a plurality of different print modes, wherein each print mode has an associated line print time. A data interface receives image data and associated metadata for a print job from a pre-processing system, the metadata including print mode metadata. A digital memory stores a plurality of pulse timing functions, each pulse timing function corresponding to one of the line print times associated with the plurality of print modes. A metadata interpreter interprets the metadata and determines the print mode to be used to print the image data. A printer module controller controls the printer module to print the image data using the pulse timing function corresponding to the line print time associated with the print mode, wherein each light source is activated for a pulse count corresponding to a pixel code value of an associated image pixel.

Abstract: A print engine includes a printer module for printing image data in a plurality of different print modes, wherein each print mode has an associated line print time. A data interface receives image data and associated metadata for a print job from a pre-processing system, the metadata including print mode metadata. A digital memory stores a plurality of pulse timing functions, each pulse timing function corresponding to one of the line print times associated with the plurality of print modes. A metadata interpreter interprets the metadata and determines the print mode to be used to print the image data. A printer module controller controls the printer module to print the image data using the pulse timing function corresponding to the line print time associated with the print mode, wherein each light source is activated for a pulse count corresponding to a pixel code value of an associated image pixel.

Abstract: A print engine is adapted to print image data from a plurality of pre-processing systems that supply image data at different image resolutions and halftoning states. A data interface receives the image data and associated metadata including an image resolution parameter and a halftone state parameter. A metadata interpreter interprets the metadata and determines image processing operations that are required to prepare the image data for printing using a printer module. A resolution modification processor module processes the image data to modify its resolution if the metadata interpreter determines that the image resolution of the image data does not match the printer resolution. A halftone processor module processes the image data by applying a halftoning operation if the metadata interpreter determines that the image data is not in an appropriate halftoning state.

Abstract: A method is described for controlling a printhead including an array of light sources. An aim exposure function is provided which gives an aim exposure as a function of an integer pulse count. An initial pulse timing function is also provided which defines an exposure time as a function of pulse count. A light output function for the light sources is determined responsive to the pulse timing function, wherein the light output function gives a light output of the light sources as a function of exposure time. The pulse timing function is updated responsive to the light output function and the aim exposure function. The process is repeated until a predefined iteration termination criterion is satisfied. The determined pulse timing function is used to control the printhead, wherein each light source is activated for a pulse count corresponding to a pixel code value of an associated image pixel.

Abstract: Image descriptions described using an image description language are provided for a plurality of images. Image bitmaps are determined by processing the image descriptions, each image bitmap including an array of image pixels. The image bitmaps are stored in an array of digital storage devices, with different portions of the image bitmaps being stored in different digital storage devices, where an allocation table is used to indicate where each portion is stored. When one of the digital storage devices fails, the allocation table is analyzed to determine which portions of the image bitmaps were stored in the failed digital storage device. The lost portions are re-rendered by processing corresponding portions of the image descriptions, and the re-rendered portions are stored in the array of digital storage devices.

Abstract: Image descriptions described using an image description language are provided for a plurality of images. Image bitmaps are determined by processing the image descriptions, each image bitmap including an array of image pixels. The image bitmaps are stored in an array of digital storage devices, with different portions of the image bitmaps being stored in different digital storage devices, where an allocation table is used to indicate where each portion is stored. When one of the digital storage devices fails, the allocation table is analyzed to determine which portions of the image bitmaps were stored in the failed digital storage device. The lost portions are re-rendered by processing corresponding portions of the image descriptions, and the re-rendered portions are stored in the array of digital storage devices.

Abstract: A print engine is adapted to print image data from a plurality of pre-processing systems that supply image data at different image resolutions and halftoning states. A data interface receives the image data and associated metadata including an image resolution parameter and a halftone state parameter. A metadata interpreter interprets the metadata and determines image processing operations that are required to prepare the image data for printing using a printer module. A resolution modification processor module processes the image data to modify its resolution if the metadata interpreter determines that the image resolution of the image data does not match the printer resolution. A halftone processor module processes the image data by applying a halftoning operation if the metadata interpreter determines that the image data is not in an appropriate halftoning state.

Abstract: A computational halftoning process determines a halftoned image having halftoned pixel values by processing an array of input pixels. For each input pixel, an array of high-resolution printer coordinates is defined at a higher spatial resolution than the printer resolution, and a coordinate transformation is applied to determine a corresponding array of high-resolution dot coordinates. An array of high-resolution halftoned pixel values is then determined responsive to the code value of the input pixel by addressing a halftone dot function using the array of high-resolution dot coordinates. A halftoned pixel value is then determined by averaging the high-resolution halftoned pixel values.