Halftone dot image discrimination method and image processing device

摘要

A device and a method for detecting isolated points in image data by the application of an isolated point detection filter, and discriminating whether or not the image data are a halftone dot image by the number of isolated point detected within a predetermined area. The size of the isolated points is reduced so as to be smaller than the isolated point detection filter by culling the image. In this way isolated points can be detected using the same isolated point detection filter regardless of the resolution of the image data.