ImageXpert印刷图文分析系统检验印刷文件灰度值初探

A Preliminary Study on the Gray Value of Printed Documents with the ImageXpert Analytic System

目的探索打印与复印文件灰度值特征及其对打印与复印文件鉴别的应用。方法使用ImageXpert印刷图文分析系统测量打印复印文件相似区域的灰度平均值,并以此为切入点研究、总结印刷文件相关区域灰度平均值的变化规律。结果同设备的打印与复印文件相同区域内灰度平均值互有高低,而同一印刷文件上不同区域内灰度平均值差异有规律可循。结论利用印刷文件上相同区域内灰度平均值鉴别打印与复印文件的可行性不高,但通过其他印刷文件的灰度平均值规律分析、鉴别打印与复印文件则有待进一步研究。

Objective To analyze the gray value of printed documents and evaluate its application in the discrimination between printed and photocopied documents. Method The ImageXpert analytic system for printed graphics and texts was used to measure the average gray value in the similarity regions of printed documents, and the regular change were explored and summarized. Results The gray values of printed and photocopied files produced by the same machine were different. But with a high deviation of the values among different machines, there was no regularity in a large scale. However, the average values in different regions of the same page were different. Conclusion To distinguish printed documents from photocopied ones based on the average of gray value is not applicable, but the convergence of gray values in different regions of the same page is worth further study.