| 摘要 |
PURPOSE:To stably evaluate the quality of printed matters without a malfunction in evaluating the quality by comparing the entire image data, into which two or more vertical and horizontal pixels in optional areas are grouped, with each other when a displacement of the margin of a sheet of printed paper is detected. CONSTITUTION:Image data for every pixel of a sheet of printed paper detected by a sensor 2 are digitized by an A/D converter 19 and compared with sample data based on address date from a bus 11 by a comparison circuit 20. In the case the difference between the image data and the sample data is out of a threshold value, it is determined as an abnormal printing and a NG is issued and stored in a NG position memory 21. On the other hand, a grouped image comparison circuit 28 is connected to the comparison circuit 20 and two or more vertical and horizontal pixels are grouped into 32X32 pixel data, for example. The grouped image data are stored in a grouped data exclusive memory in the circuit 28 and differences between the sample date and the grouped image data which are input successively are calculated. When the difference exceeds the threshold value, the data are stored in a grouped image NG position memory 29. |
