Abstract: Objective To study the time information contained in the print files of some models of Konica Minolta printers, find out the distribution period of the tracking dots, summarize the time code of the tracking dots, and decipher the time information of the tracking dots. Methods Using Digital SLR camera and image processing software to extract and mark the distribution period of the tracking dots, compare and analyze a large number of samples printed at different times, summarize the distribution period of the tracking dots, and decipher the time information of the tracking dots. Results It was found that the distribution period of the tracking dots on the printed documents of the Konica Minolta color laser printer was arranged in a stepped manner, totaling 16 columns and 24 rows; The time code of the tracking code follows the basic rules of base-six; The information of the year, month, day, and time corresponding to the tracking dots area is found, and the time information is deciphered. Conclusions The research shows that this method can solve the printing time of some models of Konica Minolta printers, which provides a new reference for printing document inspection.

Key words: Konica Minolta, tracking dots, comparison analysis, time information

摘要： 目的 针对柯尼卡美能达部分型号打印机打印文件中所包含的时间信息进行研究，找出暗记点阵分布周期，总结暗记点阵的时间编码规律，破译并解码时间信息。方法 借助单反数码相机和图像处理软件提取并标示打印暗记点阵，对大量不同时间打印的样本进行比对分析，归纳暗记点阵的分布周期、找出时间编码规律。结果 发现用于实验的柯尼卡美能达彩色激光打印机打印文件上的暗记点阵周期呈阶梯状排列，共计16列24行；实验对象的暗记在时间编码上均遵循六进制的基本规则；区分出了年、月、日、时在打印文件中所对应的暗记区域，破译并解码了该时间信息。结论 研究表明，该方法可以解出柯尼卡美能达部分型号彩色激光打印机打印文件的形成时间，为打印文件检验提供了新的参考。

关键词: 柯尼卡美能达, 暗记, 比对分析, 时间信息