Patent ID: 8432579
Filing Date: 2013-04-30
Classification: B41J,G03G,G06K,H04N

Abstract:
1. An image forming apparatus comprising: an image forming station for forming a pattern image on a recording material; an image reading station for reading a pattern image formed by said image forming station; and a tone gradation corrector for calculating a tone gradation property indicative of a density value property of an input image signal, converting the tone gradation property to a halftone dot area property indicative of a halftone dot area percentage of the input image signal, calculating the halftone dot area property on the basis of a density of the pattern image read by said image reading station, and executing tone gradation correction of said image forming station on the basis of the halftone dot area property, wherein said tone gradation corrector executes the tone gradation correction such that a dot gain property, which is a difference between an input halftone dot area percentage and an output halftone dot area percentage, is within a predetermined range, and wherein the output halftone dot area percentage is determined according to: where: