Posted by Duncan Hill on 12/05/05 18:56

On Monday 05 December 2005 16:36, Chirantan Ghosh wrote:
> As you suggested, I really would love to get a watermark which is invisible
> with initial viewing but activated once a copying/printing command ( Can be
> Ctrl+C or Alt+Printscreen) is used.

Once the browser has the content, it's out of PHP's hands. It's on the disk
of the remote client, and they can do what they like with it. To print an
image or web page that's in my disk cache, I don't need to use my web browser
- I can just go to the cache in my file manager and print it.

Unless you write a dedicated viewing application that must be used to view the
content, you're not going to have much luck.

If you want a watermark on print, just watermark the image anyway.

Steganography might help, but only in the digital world.

Are you sure you're tackling the right problem from the right angle?

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