Automatic Authentication of Handwritten Documents via Low Density Pixel Measurements

We introduce an effective approach for automatic offline au- thentication of handwritten samples where the forgeries are skillfully done, i.e., the true and forgery sample appearances are almost alike. Subtle details of temporal information used in online verification are not available offline and are also hard to recover robustly. Thus the spatial dynamic information like the pen-tip pressure characteristics are considered, emphasizing on the extraction of low density pixels. The points result from the ballistic rhythm of a genuine signature which a forgery, however skillful that may be, always lacks. Ten effective features, including these low density points and den- sity ratio, are proposed to make the distinction between a true and a forgery sample. An adaptive decision criteria is also derived for better verification judgements.

Authors:

• Abhijit Mitra
• Pranab Kumar Banerjee
• C. Ardil

Keywords:

• Handwritten document verification
• Skilled forgeries
• Low density pixels
• Adaptive decision boundary.

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