Printed Document Authentication Using Watermarking Technique

Forgeries related with official printed documents can easily be performed with the aid of today's advanced electronic devices such as scanners and computers. The forged documents are usually undetectable by human eyes and it is with this regard that there is an urgent need to find solutions to the threat of counterfeiting of such documents. With watermarking technique, information that is used to determine the validity of printed document can be embedded in the document. The embedded information can be imperceptible to human eyes, thus the process of forgery is made harder for the attackers. To authenticate the owner of the document, the embedded watermark is extracted from the watermarked document. However, in the verification process the printed document may suffer from printing and scanning (PS) distortion and as such it is necessary to resolve the noise and unwanted rotation as well as any degradation made by printing and scanning. This study proposed a watermarking technique to address this issue.