Patent ID: 8665458
Filing Date: 2014-03-04
Classification: G06F,G06K,H04N

Abstract:
1. An image forming apparatus which generates print data based on control data for printing a page, which is received from an external device, and which forms an image based on the print data, comprising: a control unit including a plurality of arithmetic processing units, wherein the control unit is configured to perform the following operations with respect to a predetermined page based on the control data for printing the page: an image forming unit which forms an image based on the generated print data outputted from the control unit, wherein the control unit is configured to determine whether generation of print data based on the display list generated for each band can be completed within the output interval for all of the bands in one page, if the control unit determines that generation of print data can be completed within the output interval for all of the bands in one page: if the control unit determines that generation of print data based on the display list generated for each band can not to be completed within the output interval for any one band in one page: output the generated print data at the output timing corresponding to each band; and the control unit is configured to designate at least one arithmetic processing unit which is not executing a rasterizing process among the plurality of arithmetic processing units to carry out dividing a page in units of a band and generating a display list for each band with respect to a page that comes after the predetermined page in parallel with the rasterizing process; wherein the control unit is configured to determine which arithmetic processing units are available to execute a rasterizing process among the plurality of arithmetic processing units, and the control unit is configured to execute a first processing mode in which rasterizing processes of one or a plurality of bands are executed in parallel by at least two arithmetic processing units among the arithmetic processing units which are determined as being available to execute a rasterizing process, a second processing mode in which, while a rasterizing process of another band is executed in one arithmetic processing unit, a rasterizing process is executed for a band which is determined that the rasterizing process can not be completed within the output interval in parallel by another one or more arithmetic processing units, and a third processing mode in which a rasterizing process of any one band in the page is executed before a rasterizing process of a first band, and when the control unit determines that generation of print data can not be completed within the output interval, the control unit is configured to determine whether generation of print data can be completed within the output interval by executing the first processing mode, when the control unit determines that generation of print data can not be completed within the output interval even if the first processing mode is executed, the control unit is configured to determine whether generation of print data can be completed within the output interval by executing the second processing mode, and when the control unit determines that generation of print data can not be completed within the output interval even when the second processing mode is executed, the control unit is configured to execute the third processing mode.