Speed-up method and apparatus for two-dimensional facsimile coding and decoding

摘要

A method and device for speeding the transmission and reception of documents by digital facsimile systems employing two-dimensional coding. Information regarding a reference line of a document need not be reaccessed from memory during the processing of the scan line next-following a uni-color reference line. A user-accessible paper-width register utilized in conjunction with a comparator according to the speed-up method permits ready detection of uni-color lines and permits encoding and decoding according to either of two international standards. Utilization of the paper-width register affords ready availability of the accumulated run-length of picture elements within uni-color lines without the need to accumulate the run length or reaccess the uni-color reference line.