PIXEL NUMBER CHANGING TECHNOLOGY OF HALFTONE DOT USING DOT EDGE DETECTION SCHEME

摘要

PPROBLEM TO BE SOLVED: To provide a picture calibration method free from influence of rounding error. PSOLUTION: The picture calibration method corrects a halftone bitmap original image with a considered color correction function, and it is the method of forming the halftone bitmapped image by which the color correction is carried out. The method comprises a step which provides a halftone bitmap original image, a step which estimates the dot area rate of the halftone bitmap original image in a set of accessory image block, a step which calculates the dot area rate used as a target based on the considered color calibration, a step which calculates the pixel number (N) of the halftone bitmapped image converting to on-state or off-state about each accessory image block, and a step which changes N pixels in the halftone bitmap original image about each accessory image block respectively into either on- or off-state and forms the improved halftone bitmapped image which includes the dot rea rate used as a target. PCOPYRIGHT: (C)2004,JPO