US Patent 7502130 Control method of a host computer

In a host computer connected to a printer, a determination is made as to whether data should be transmitted to the printer in a printer language or expanded into bit map image data before transmission, and the data in the printer language, or the expanded bit map image data, is transmitted to the printer. The determination of whether to transmit data in a printer language or expand into a bit map image before transmission is made based on an estimate of the time required for expansion by both the printer and by the host computer. If the printer can expand a first page of data into a bit map image in parallel with expansion by the host computer of a second page of data into bit map data, then the first page of data is transmitted in the printer language and the second page of data is expanded into pit map image data before transmission.