Patent ID: RE38732

Claim:
A printing system for printing from a source of drawing instructions a two dimensional image reducible to pixels arranged in a plurality of ranked image lines, comprising: a storage means having a compressed region and an uncompressed region, each having a designated capacity and each being arranged to store pixels of one or more of said plurality of image lines; drawing means coupled to said storage means and adapted to be coupled to said source of drawing instructions for responding thereto, said drawing means being operable to store new pixels in said storage means for successively selected ones of said image lines, said drawing means including: (a) conditional means for compressively encoding and moving from said uncompressed region to said compressed region a remote one of said image lines, if (i) the selected one of said image lines is in said compressed region and (ii) said uncompressed region has reached its designated capacity; (b) decompression means for expansively decoding said selected one of said image lines, if located in said compressed region; and (c) insertion means for inserting one or more new pixels according to said drawing instructions into said selected one of said image lines by storing said selected one in said uncompressed region; and printing means coupled to said storage means for printing said plurality of image lines in rank order, decompressing compressed ones of said image lines from said compressed region before printing.