The Applied Research Of The Digital Watermarking Of Color Laser Printing Machine In The Forensic Document Examination

Color laser printing machines make it possible to forge or alter various bills or colorful documents. They also challenge document examinations in related fields. However, the emergence of the digital watermarking technology has made a major breakthrough in this problem. Through the identification and research of the "digital watermark", we can identify the identity and the formation time of the color mechanism file more accurately. So as to provide more identification methods and the enlightenment of the document identification work in the future.The first chapter of this paper introduces the concept, background, application principle, research and application of digital watermarking technology and the technology of digital watermarking for color laser printing machines.Mainly Analyzes the application conditions and basic testing fields in the Nondestructive identification briefly from the aspect of the origin.In chapter two,it mainly evalates and analyzes, the digital watermarking technology used upon color laser printing machines in the process of the Forensic Document Examination from the perspective of dialectics, illustrating the importance of the application of this technology to the inspection and its current problems from the advantages and disadvantages. It further demonstrates the significance of the Digital Watermarking of Common Color Laser Printing Machine.In chapter three, the author maked various experimental researches on digital watermarking lattice of particular color laser printer based on marketing research. In order to observe and summarize such lattice’s distribute discipline and its intrinsic characteristic.This conclusion solves some difficulties in identification area, such as the identical cognizance of machine-made color files type and attribute distinguish, formation time, formation sequence, addition and debasement.In chapter four, the author forecasts the development and improvement direction of digital watermarking of color laser printer in document retrieval; meanwhile, further thoughts and tactics are raised in its future application system and technical innovation.