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Study of Color Laser Printer and Photocopier Class Using a Pattern Location Measurement Method
Jiang-Chun Li1, Biao Li2, Xing-Zhou Han3
1Hubie Key Laboratory of Forensic Science, Department of Forensic science and Intelligence, Hubei University of Police, No. 99 NanNiWang Road, Qiaokou District, Wuhan, Hubei, 430035, China.
Abstract:
A trace code pattern location measurement approach is proposed. It includes a method that can precisely extract the trace code pattern to identify the color laser printer or photocopier class. In this study, we collected 379 samples from 15 brands, including 129 models and 196 printers or photocopiers. The trace code pattern class is identified. Four class characteristics are used to identify the print source: (i) the relation between the pattern and print output direction; (ii) observation of the shape features from among the trace code pattern units; (iii) the feature arrangement from among the trace code pattern units; and (iv) the arrangement relation of the trace code pattern. Blind testing shows that the accuracy of the proposed method is approximately 96.9% for the Questioned Document Examiners, and 84.3% in the non-Questioned Document Examiners. It is thus an effective technique for determining a print's color laser printer or photocopier source class.
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