Printing using pre-defined bitmaps

摘要

Apparatus including a print head (11) with an array of printing elements which are selectively operable to print pixels of an image to be printed on a substrate (14) includes a computer controller (22) which is operably connected to a data source (25) which provides data to the computer controller (22) relating to the nature of an image to be printed. A memory (30) includes a plurality of pre-defined bitmaps of parts of an image which may be printed, and provides image data to the controller (22) where the image data contains an image part for which a pre-defined bitmap exists in the memory (30). The pre-defined bitmap is retrieved from the memory (30) and provided to the print head 11 for printing. The pre-defined bitmaps may represent digits (36,37) or words e.g. month names (38). Image data comprising pre-defined components e.g. a label (40) indicating a "sell-by" date may thus be printed more efficiently, without the need to render the pre-defined parts of an image.