# Watermark Applet

This applet demonstrates the watermarking approach of the Kutter-Jordan-Bossen mentioned in the book as a spatial domain watermarking technology. You can watermark your images and save your image on your computer.
First open the orginal image, it will appear on the left side of the screen. Then embed the watermark, input parameters are your watermarking string (max. 7 characters) and your secret key (PIN). The watermarked image will appear on the right side of the screen. To have a better view to the changes done by the watermarking scheme, you can choose the difference view. You see blue areas, where the watermarking information is embedded.
You can now save your watermarked image. If you want to retrieve the watermarking information, either you have already the watermarked image on the left screen or you can load any watermarked image from your computer, then select retrieve. Enter your secret key (PIN) as parameter.

To handle geometric distortions you can apply some selected media operations within the watermark applet to the watermarked image in the setup. You can then try to retrieve the watermarking information. Please select the distortion parameter additionally to your secret key (PIN) during the retrieval process to increase the search performance. For the retrieval you do not need the orginal image.

In the setup you can also edit the watermarking parameter density, ???? and enhancement factor. The latter increases the difference view to see the changes more intensively. The density and ??? parameter determine how the watermarking information is spread of the image, see the literature.

The service will be Supported only with Netscape version greater 4.04 and Java 1.12
or Internet Explorer version 4.0 or greater.

Click Here to start Applet

If you have any question please contact Jana Dittmann