Sub-banding of display list and video buffer for page rendering in a digital signal processor

Abstract

A print method converts page description data specifying a print document into pixel data. The print system includes a central processing unit, a first memory and a second memory that is smaller but faster than the first memory. The method extracts a display list from the page description data (), allocates space within the first memory to serve as a page buffer and divides the page buffer within the first memory into a plurality of sub-bands. Each sub-band is smaller than the second memory. For each sub-band the method renders pixels of a current sub-band into the second memory (). When the sub-band is completely rendered, the method transfers pixel data from the second memory to the current sub-band of the page buffer (). When all sub-bands are rendered, the page is printed by transfer of data from the page buffer to a print engine (). The central processing unit and the second memory are preferably disposed on the same integrated circuit.