Source Printer Classification Using Printer Specific Local Texture Descriptor

The knowledge of the source printer can help in printed text document authentication, copyright ownership, and provide important clues about the author of a fraudulent document along with his/her potential means and motives. The development of automated systems for classifying printed documents based on their source printer, using image processing techniques, is gaining a lot of attention in multimedia forensics. Currently, the state-of-the-art systems require that the font of letters present in the test documents of unknown origin must be available in those used for training the classifier. In this paper, we attempt to take the first step toward overcoming this limitation. Specifically, we introduce a novel printer specific local texture descriptor. The highlight of our technique is the use of encoding and regrouping strategy based on small linear-shaped structures composed of pixels having similar intensity and gradient. The results of experiments performed on two separate datasets show that: 1) on a publicly available dataset, the proposed method outperforms state-of-the-art algorithms for characters printed in the same font and reduces the confusion between the printers of same brand and model on another dataset having documents printed in four different fonts, the proposed method outperforms state-of-the-art methods for cross font experiments.