Patent ID: 7298525

Claim:
An image processing device, comprising: an inputting portion receiving input data indicative of a density value of one color component for one pixel in a desired image; a judging unit judging whether or not the density value of the input data is near to a reference value, wherein the density value of the input data is judged to be near to the reference value when a difference between the density value and the reference value is within a predetermined range; a threshold storing portion previously storing therein a predetermined threshold; a noise adding portion adding a noise to either one of the density value of the input data and the threshold when it is judged that the density value of the input data is near to the reference value; a correcting portion correcting the input data by a correction amount that is determined dependently on an error value which is determined at at least one pixel that has been already-processed and that is located adjacent to the subject pixel, thereby converting the input data into corrected data; a comparing portion comparing the corrected data with the threshold; an outputting portion outputting output data based on the compared results, thereby converting the corrected data into the output data; a relative density setting portion setting a relative density value that corresponds to the output data; and an error calculating portion calculating an error value for the subject pixel based on a difference between the corrected data and the relative density value.