The goal of this application is to detect any alterations and modifications made to an image.
The three pictures below illustrate this application.
But it would also be hidden as an invisible watermark in the passport photo.
If anyone tries to tamper with the passport by replacing the photo, it would be possible to detect the change by scanning the passport and verifying the name hidden in the photo.
On the left is an example of a protected identity card.
The identity number "123456789" is written in clear text on the card and hidden as a digital watermark in the identity photo.
Such applications are especially of interest for official documents, such as contracts.
For example, the digital watermark can be used to embed the name of the lawyer or other key monetary amounts.
The picture on the left shows a printing machine from Intercard for various types of plastic cards (Courtesy of Intercard, Switzerland).
Another application is the authentication of image content.