PERFECTING PRESS DEVICE

摘要

It is possible to perform perfecting press capable of preventing "strike through" and not giving uncomfortable feeling to a user. An image signal of two pages, i.e., a front page and a back page of an original (1) is read by an image reading section (10) and output to a control section (90) (see Fig. 2). The image signal which has been input is subjected to A/D conversion and then to normal image processing so as to generate image data, which is stored in an image memory (92). Image data on an area of 100 lines is successively read out and an image concentration detection section (94) calculates the percentage of number of black data with respect to the total number of data as an image concentration A. When the image concentrations A of the image data on the front page and the back page stored in the image memory (92) are all 30% or below, the image data is judged to mostly consist of characters and printing is performed with a normal printing concentration. When the image concentration A of at least one area exceeds 30%, the image data is judged to include a solid portion and the image data on the front page and the back page is subjected to a thinning process which is a printing concentration reduction process when generating mimeograph data, thereby reducing the printing concentration.