Handcuff Digital Thieves

Digital artists turn to sophisticated labeling systems to help protect their work

Philip Chudy

When Leonardo da Vinci died, he knew of 12 copies of The Last Supper -- works of former apprentices. The genuine work consumed two years of his life, but da Vinci could gain consolation in the fact that, without lots of talent and hours (or years) of labor, no one would be able to truly copy his paintings.

In contrast, today's imaging and desktop publishing tools let virtually anyone easily and inexpensively duplicate, manipulate, or reprint the works of an artist. Each copy of a digital work of art is identical to its original.

Digital copying is, of course, not restricted to still images; it includes video, music, and mult imedia. CD-ROMs, digital video, audio broadcasting, and the worldwide availability of the Internet make it impossible for an artist or an on-line publisher to track digital material.

Outdated Copyright Laws

"Copyright law has not kept pace with technological and economic changes," says Francois Boisson, coordinator of the European Information Technology for Information Science (EURITIS) initiative of the European Commission (EC). Within the Esprit 2 program, the EC started the Copyright in Transmitted Elec

Digital Copyright

"Copyright labels must be difficult to remove, must survive all kinds of data-compression techniques and, of course, must not reduce the aesthetic value of the image," explains Zhao. Obviously, the embedding of a label in the least significant bits of an image file does not satisfy these requirements.

Embedding Hidden Codes

Techniques that allow for the embedding of hidden codes in image, video, or audio data are called steganographic or digital fingerprints . Fingerprinting systems can be based on statistical algorithms that modulate the noise signal in an image or sound file and add the modulated signal to the original data. In this way, the encoded identification is distributed throughout the entire work as subliminal noise and can't be fully eliminated from the file.

g the retrieval software.

All three systems can survive any format conversions, data compression, and cropping mechanisms, and the identification code is still retrievable, despite conversion to analog or print form. The core algorithms behind these systems are not revolutionary, but many artists believe they are of real help in protecting their work.

SysCOP embeds robust labels into gray-scaled color or binary images, PostScript files, and digital video. It supports JPEG, TIFF, PPM, and MPEG and runs under Unix V/BSD and Sun Solaris 2.3. A version for the Mac is under development.

Frauenhofer Institute recently launched on the Web a free image-labeling service ( http://sagittarius.igd.fhg.de:64325 ) based on SysCOP. It includes registration, labeling, and verification of labeled data. The software can also be downloaded freely from the company's Web site.

Highwater FBI offers its program as a plug-in for Adobe Photoshop and as a stand-alone application for the Mac. It sells for about 250 pounds UK. The company also plans to license its technology to be implemented in multimedia applications and even in such devices as scanners and cameras.

For high-volume picture users, such as stock-photo li braries, picture agencies, and information providers, Highwater FBI is developing FBI Pro -- a stand-alone batch-processing application that should be shipping by the time you read this. The license price of FBI Pro varies, according to installation and throughput. "As a rough guide, we would estimate the cost of a site license for a medium-size library/agency handling around 15,000 images per year to be about 7000 Pounds UK," says company spokesman Alan Bartlett.

The FBI program refuses to sign an image that already has an FBI signature. This might cause some inconvenience in certain legitimate circumstances, and it might not be more than a token hindrance for the truly determined thief, but the notion of disabling a user's ability to re-sign already-defined third-party property is music to the ears of digitally phobic artists.

Digimarc is presently not marketed as a product: The company is selling the technology for integration. Expect products incorporating Digimarc's technology to appear durin g the first half of this year.

No Human Intervention

The next challenge that image-signing and fingerprinting systems face is finding a way to embed signals within works optimized to machine interpretations. The idea is to permit automated tracking devices to operate without human intervention.

Central to this idea is the application of multiple overlaid markings. Some of these can be overtly soft, which means they are open to public access without special keys. Today, royalty-collection agencies employ human staffers who tune in and track the use of video and music material. In the future, they might operate more economically -- and perhaps more accurately -- by using computer-based fingerprint-retrieval systems. Programs and commercials would each be tagged with a public-access signal that a computer would check and use to identify the material.

Digimarc and Highwater FBI are trying to establish escrow database services for users of their technology. The FBI detector softwar e directs identification codes back to a main database, where author identity and more data can be given out.

Digimarc envisions multiple advantages for artists with such a scheme. Escrowing would alsozzz mean advertising, since prospective buyers of images could be given browsing privileges in the database. Artists would then pay fees for escrow services, but at the same time they would have a good chance to manage and promote their artwork without needing costly agents.

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WHERE TO FIND

Digimarc

Portland, OR
Phone:
    (503) 626-8811
Fax:      (503) 626-8844
E-Mail:   
info@digimarc.com


EURITIS

Montigny-le-Bretonneux, France
Phone:    +33 1 30 12 00 71
Fax:      +33 1 30 60 04 61

Frauenhofer Institute for Computer Graphics

Darmstadt, Germany
Phone:    +49 6151 155412
Fax:      +49 6151 155444
E-Mail:   
zhao@igd.fhd.de

Internet: 
http://sagittarius.igd.fhg.de:64325


Highwater FBI

Cheltenham, U.K.
Phone:    +44 1242 221390
Fax:      +44 1242 251600
E-Mail:   
fbi@hwuk.demon.co.uk

Internet: 
http://www.demon.co.uk/highwater


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Philip Chudy is a digital artist and freelance writer in Bingen, Germany. You can reach him by sending E-mail to chudy@tap.de .