Automatic Line Orientation Measurement for Questioned Document Examination

In questioned document examination many different problems arise: documents can be forged or altered, signatures can be counterfeited, etc. When experts attempt to identify such forgeries manually, they use among others line orientation as a feature. This paper describes an automatic mean for measuring the line justification and helping the specialist to find suspicious lines. The goal is to use this method as one of several screening tools for scanning large document collections for the potential presence of forgeries. This method extracts the text-lines, measures their orientation angle and decides the validity of these measured angles based on previously trained parameters.