HALF-TONE GENERATOR AND HALF-TONE GENERATING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a configuration that attains high speed processing in the generator that generates half-tone data from multilevel image data. SOLUTION: Registers 23, 25 receive all threshold data that are applied to processing threshold data read from a threshold matrix memory 21 in a reuse enable way till end of a processing scanning line, output the data to a plurality of comparison means selectively to execute parallel comparison processing. The threshold value data set to the registers are sequentially shifted and used repetitively. Furthermore, the registers 23, 25 receive the threshold data of a next scanning line for the comparison processing and the comparison processing for the succeeding scanning line is executed as a pipeline processing when the processing of one scanning line is finished. Reading of the threshold data from the memory is conducted once enough for each processed scanning line and reading of the data during generation of the half tone data of the preceding line is read.