Symmetry detecting method and system of printing matter

Abstract

The invention provides symmetry detecting method and system of a printing matter. The method comprises the following steps: preprocessing an image on real time; determining the paper side of the image; determining the distance from the boundary of a marking area to the paper side and the width of the marking area; determining the whole cycle starting positions of the upper left and right lower marking characteristics; performing symmetry analysis for the interested areas in the left side and the right side, including calculating the symmetry measuring degree and determining the symmetry defect. According to the method and system, the real-time detection scheme is provided for the overprinting product, one of the characteristics is that the speed is fast, and the real-time processing effect can be realized, and another characteristic is that the robustness is high; on the basis of the two characteristics above, the method and system can be applied to real-time detecting in the actual production process in order to timely screen out unqualified products, and as a result, the detecting efficiency and the economic benefit are increased.

Description

technical field [0001] The method belongs to the technical field of image processing and recognition, and in particular relates to a method and system for detecting the symmetry of a printed matter. Background technique [0002] Due to the imperfect printing technology and some unavoidable random factors, defects such as blurred text, missing printing, scratches, and inaccurate registration often appear during the printing process. Taking tipping paper overprinting as an example, the hot stamping edge and hot stamping characters of tipping paper are sequential processes, and machine or human factors may cause overprint deviation, which is specifically manifested as the deviation of the upper, lower, left, and right positions between the gold edge and the paper edge, and the text and the gold edge; In the tipping paper, there are often defects such as missing printing of gold edges, false bronzing of text, lack of pens and strokes, and blurred text printing. For such defects...

AI Technical Summary

Problems solved by technology

[0004] In order to make full use of digital image processing and recognition technology, fully tap its practical value, and make it effectively serve the printing industry, this invention provides a technical solution for printing symmetry detection, which aims to solve the current situation where there are no measurement and control conditions at home and abroad Under the current situation, it is not possible to automatically and real-time detect and control the defects such as inaccurate registration of printed matter

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