An Experimental Study On The Feature Change Of In Iterative Copying Of Common Copiers

Copy files as an important part of the documents examination.Since it requires not only the knowledge of traditional morphology,but also the principle of copying documents of various devices,it is difficult to verify the identification.Therefore,it has always been a major difficulty in the field of document examination.Among them,iterative copying as a new problem is seldom studied by experts and scholars.Although there are lot of literatures about copying documents at home and abroad,it is seldom applied to the test of iterative copying.At the same time,with the rapid development of printing equipment,a combination of printing,copying,scanning,faxing gradually gets the favor of more people,it also broke the limit to copy with digital composite mechanism,and increased more ways for copy.This is also a challenge for documents examination.So,I choose the seals as sample,use a variety of common copier to do iterative copying,aims to study the feature changes of iterative copying of different copiers and the different times iterative copying of the same copier,and carried out a statistical analysis on the feature changes,find out if there is a rule.This study is divided into four chapters.The first chapter explains the concept of iterative copying,by checking the relevant literature to analyze the research status ofiterative copying at home and abroad,explain the significance of the research on the feature changes of iterative copying,and also shows its complexity.The second chapter is the basic content of this study,including the principle and purpose of the experiment,the design and the preparation of the experiment,and the production process of the experimental samples.The third chapter is the core chapter of this article.The main contents of it is to use software like Photoshop,Excel,and IPP,to do counting,analyzing and studying on the detail changes of seal's iterative copying,the change of the displacement data,the change of the ink-point characteristics of the printed text,etc.And try to found the relevant rules.The fourth chapter analyzes the iterative copying from two aspects of document examination specification and practical application,and expounds how to apply the research of iterative copying to the daily identification practice.In a word,this study takes the seal as an example,through the experimental study of the feature changes in iterative copying which made by common copying equipments,to get the data of three aspects: the detail changes of seal's iterative copying,the change of seal's displacement,the change of the ink-point characteristics of the printed text.Hope to provide some help for the practical application of iterative copying examination.