Digital Watermark

Financial Times, 22 Feb 96

Digital watermark protects copyright

Scientists at the NEC Research Institute in Princeton
believe they have developed "a fundamental enabling
technology" for protecting the copyright of images and
music on the Internet.

They have developed a secure method of producing a
digital watermark, an invisible code that identifies the
owner, which is permanently embedded in the multimedia
data.

Attempts to remove the watermark would be virtually
impossible without degrading the image quality. Moreover,
counterfeiting would be almost impossible, says NEC. the
Japanese electronics company.

The digital watermark is designed to be used in
conjunction with cryptography, which limits access to
encrypted data to legitimate users.

NEC Research Institute:
US, tel 609-520-1555
fax 609-951-2481.

Creating watermarks that can't be removed without degrading
image quality is not especially difficult.  The two tricky bits are
durability and collusion protection.

	Durability involves ensuring enough of a watermark remains
after the image is converted to a JPEG.  Colusion protection is making
sure that users can't compare images and remove the watermark without
a large number of users being involved.

Adam


| Financial Times, 22 Feb 96

| Attempts to remove the watermark would be virtually
| impossible without degrading the image quality. Moreover,
| counterfeiting would be almost impossible, says NEC. the
| Japanese electronics company.

-- 
"It is seldom that liberty of any kind is lost all at once."
					               -Hume

Does anyone know if the source code for this is
available?

I have a bunch of photos of myself modeling clear plastic
raincoats that I want to put on the net, but I would like
to try to tag them before I do.

Mark