Image creation method and apparatus (ART77)

摘要

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.