采用平板扫描仪、数码相机等图像捕捉设备,将印刷文件转化为数字图像加以检验目前是文书鉴定领域研究的热点,这种方法与页面经扫描后成为图像的数字印刷有相似之处,对数字印刷图像质量的评估方法或可适用于分析文件.本综述从标准内容、度量方式、与国内标准比较及在印刷文件检验中的应用性四个方面,对含有较为完备的印刷质量评估方法的国际印刷质量评估标准ISO/IEC 24790进行详细解读,重点介绍了ISO/IEC 24790中大面积图形图像质量属性、字符和线条图像质量属性评估方法,并对引入基于ISO/IEC 24790标准的新方法在鉴定领域未来发展方向作出了展望.
With the widespread application of printing equipment,such as office equipment,and the development of printing technology,the conventional inspection methods,which take substantive paper documents as the analysis object and take morphological characteristics and chemical properties as the analysis points,have been unable to meet all the needs of printing document identification.At present,the method of transforming printed documents into digital images by using image capture devices such as flat-panel scanners and digital cameras has become a hot spot in the field of document identification.In many cases,files are either actively or passively converted into images for storage,and the domestic inspection standards for paper carriers cannot be applied to the inspection of such files based on digital images.The ISO/IEC 24790 standard comprehensively covers the quality inspection methods of images printed by office imaging systems,which may enrich the inspection methods of digital printed documents in China and promote the construction of digital inspection standards.This paper interprets the international standard ISO/IEC 24790,identifies the reference modes for domestic standards,and elaborates the applicability of the evaluation methods for large area graphic image quality attributes,character and line image quality attributes introduced in international standards.However,the road of quantification is still in the early stage for China.At this stage,it is necessary to consider the correlation between attributes and document inspection and the measurement accuracy of the instrument when introducing the physical indicators in the standard into document identification.Undeniably,the introduction of the international standard ISO/IEC 24790 and the establishment of a comprehensive evaluation method that reflects the relationship between the perceptual characteristics of human visual system and the physical properties of images have provided new impetus for quantitative construction.