Printable image data generation in large-scale printing

A printer for large-scale printing comprising:

• a printing processor for printing images on a printing medium, the printing processor being configured to:
• receive image data for each image of a list of images to be printed on said printing medium;
• split up the received image data of the list of images into N successive sequences corresponding to N printing steps, N being an integer greater or equal to 1, of M groups of image data of individual images, M being an integer greater than 1, each group of image data of a printing step comprising image data of at least one individual image, the number of individual images in the M groups of a given printing step corresponding to the total number of images to be printed at this printing step;
• sequentially for each printing step, distribute the M groups of image data to, respectively, M distinct processing units, each processing unit sequentially processing image data of each individual image data from a received group of image data to generate a corresponding set of printable individual image data;
• upon all said M processing units having each completed generation of a set of printable individual image data from a corresponding group of said corresponding printing step, authorize the printer to print the corresponding individual images on the printing medium, thereby the printer is operable to execute printing action as soon as a set of printable individual image data has been generated from M groups of image data by the M processing units, and continue printing action without interruption until the list of images is printed;
• receive printing arrangement data for printing individual images according to corresponding printing arrangement on the printing medium at each printing step;
• and
• index each individual image data of each group according to said printing arrangement data corresponding to said printing step, when all said M processing units have each completed generation of a set of printable individual image data from a corresponding group of said corresponding printing step, wherein the indexing further spans over one or more said M groups of image data corresponding to one printing step;
• wherein at each printing step the individual image data from the set of printable individual image data are printed on the printing medium in order according to said indexing, where each indexed individual image data of the set of printable individual image data is provided to the printer separately from the other indexed individual image data,
• wherein the printer is configured to perform the large-scale printing such that the arrangement of the individual images on the printing medium is independent from the actual grouping of the corresponding printable individual image data in the M groups.