IMAGE PROCESSING METHOD, PROGRAM, IMAGE PROCESSOR, IMAGE FORMING APPARATUS, AND IMAGE FORMING SYSTEM

摘要

PROBLEM TO BE SOLVED: To reduce design man-hours of a gamma correction table and the capacity of a memory in use and to improve a processing speed by carrying out a plurality of halftone processing providing the same gradation characteristic and executing gamma correction processing using gamma correction parameters common to each halftone processing. SOLUTION: A halftone processing section 802 adopting the image processing method includes a first halftone processing section 811 for carrying out halftone processing by the dither method and a second halftone processing section 812 for carrying out halftone processing by the error diffusion method. The second medium tone processing section 812 carrying out the error diffusion processing includes: a multi-bit conversion table 821 for converting an 8-bit input image into a 14-bit image; and a multi-bit error diffusion processing section 823 for applying the halftone processing to the 14-bit image data 822 from the multi-bit conversion table 821 by means of the multi-bit error diffusion method to output 2-bit image data, and a gamma correction processing section 814 applies gamma correction processing using common gamma correction parameters to processing results of the halftone processing sections 811, 812. COPYRIGHT: (C)2007,JPO&INPIT