APPARATUS FOR DETECTING IMAGES, METHOD FOR SEARCHING BLACK PIXEL, AND METHOD FOR DETECTING BLANK SHEETS OF PAPERS

摘要

PURPOSE: An apparatus for detecting images, a method for searching a black pixel, and a method for detecting blank sheets of papers are provided to detect blank sheets of the papers efficiently with improved accuracy. CONSTITUTION: An apparatus for detecting images includes a line density discriminator(14), a memory(9), and a selector(15). The line density discriminator(14) discriminates the line density of the paper. The memory(9) stores the threshold value corresponding to the line density. The selector(15) selects the threshold value corresponding to the line density discriminated by the discriminator. The blank sheets of the paper is detected by adjusting the threshold values. The apparatus for detecting images determines whether the paper is blank sheet on the comparison of the number of black pixels and the threshold value.