A printhead controller controls printing of a page by at least one printhead. The printhead controller, in use, receives data, in a compressed format relating to the page to be printed, the data including a page description comprising a bi-level black layer and a contone color layer. The printhead controller extracts from the compressed data relating to the bi-level black layer the contone color layer. Memory is provided for temporary storage of the expanded data. A dithering/compositing unit produces a ditherer page from the data temporally stored in the memory and feeds its out put to the printhead.
CROSS REFERENCE TO RELATED APPLICATION
The present application is a continuation of U.S. application Ser. No. 09/505,008 filed Feb. 15, 2000, now issued as U.S. Pat. No. 6,559,969, the entire contents of which are herein incorporated by reference.
Where the bandwidth of a data link between a printer and a computer is limited it may be desirable to transmit compressed page layout data over the data link.A printer controller chip is provided that processes compressed page layout data corresponding to a page layout having a bi-level black layer and a continuous tone graphics layer. The printer controller includes a number of functional modules including an edge delta runlength (EDRL) expander to derive bi-level black layer data from the compressed data. The controller also incorporates a JPEG decoder to derive continuous tone layer data from the compressed data. A halftoner and compositer module is provided to halftone the continuous tone data to bi-level CMYK data and to composite the bi-level layout data over the bi-level CMYK data to produce page layout print data. A printhead interface processes the page layout print data to generate signals to drive a pagewidth printhead.
An inkjet printer includes a body defining a print media path along which print media can pass. A disposable printhead assembly is arranged within the body and is configured to print upon print media passing along the print media path. A print media input tray is pivotally mounted with respect to the body for locating the print media in register with the print media path. A print media feed arrangement is configured to feed the print media from the input tray and along the print media path. Printer controller circuitry is arranged in the body and is operatively connected to the printhead assembly and print media feed arrangement to control operation of those components.
