Abstract: An image processing method includes a step of converting halftoned pixels of an image to be printed represented at a first lower tonal resolution into pixels represented at a second higher tonal resolution. Image processing is used on the pixels having a higher tonal resolution to reduce image quality artifacts when the pixels are printed at the first lower tonal resolution. In a preferred embodiment, the image processing includes error diffusion of a sigma delta modulation.

Abstract: A system and a method for synchronizing printing of images on both sides of a web in a double-sided web printer includes a method including printing a first image on a first side of the web by a first printing device; printing a second image on a second side of the web, opposite the first side, by a second printing device; sensing a position of the web, relative to the second printing device, by a web position measuring device; real-time communicating an electronic printing position signal, representative for the printing position of the first image on the web, between the first printing device and the second printing device; and printing the second image synchronized to the first image based on the electronic printing position signal and the position of the web relative to the second printing device.

Abstract: A method for printing more than one print job on a web based printer divides the web into logical print zones. Print jobs are assigned to different print zones by a multiplexer. The width and length of the print zones can vary during the printing as function of the print jobs. The method reduces the waste of unprinted substrate.

Abstract: An image processing method includes a step of converting halftoned pixels of an image to be printed represented at a first lower tonal resolution into pixels represented at a second higher tonal resolution. Image processing is used on the pixels having a higher tonal resolution to reduce image quality artifacts when the pixels are printed at the first lower tonal resolution. In a preferred embodiment, the image processing includes error diffusion of a sigma delta modulation.

Abstract: A method and a device for converting a color defined in a first n-dimensiontal device dependent color space to a corresponding color defined in a second m-dimensional (m.gtoreq.n; n.gtoreq.p; m>p; p.gtoreq.3) device dependent color space, wherein for each (m-p).sup.th color dimension from the second device dependent color space there is each time defined a color value and said color coordinate set of the second device dependent color space is determined on the basis of said color value.