1. A method for evaluating an interference moiré that is likely to be occurred in a halftone dot image when the object image is printed using halftone dots, the method comprising the steps of: (a) performing halftone dot meshing of object image data representing the object image to produce halftone dot image data representing a halftone dot image composed of halftone dots; (b) smoothing both the object image data and the halftone dot image data to produce smoothed object image data and smoothed halftone dot image data; and (c) obtaining a difference between the smoothed object image data and the smoothed halftone dot image data to produce interference moiré image data representing an interference moiré image.