DOT PICTURE PROCESSOR

PURPOSE:To generate a dot threshold level pattern with a large size and to allow the processing unit to cope with an optional rectangular size by not calculating a dot pattern data time by time but expanding repetitively the pattern one after another based on a prepared dot threshold level block in advance. CONSTITUTION:A dot pattern block data of a rectangular area is stored in a storage memory 107 based on a dot line number l, a dot angle theta and a dot recording density (k) designated in advance. Moreover, a link address map of a succeeding dot pattern linked to a dot pattern located at each border of longitudinal and lateral sides of the rectangular area is stored in a storage memory 108 and read and expanded repetitively based on the production of addresses. Thus, the generation of the dot pattern data is not calculated time by time and a dot pattern of a large size is generated by write/read control to/from the two storage memories 107,108. Thus, it is not required to calculate a dot pattern time by time and lots of kinds of dot patterns are generated flexibly.