Museums and the Web 2000

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Museums and the Web?

Archives & Museum Informatics
158 Lee Avenue
Toronto, Ontario
M4E 2P3 Canada

Protecting a museum's digital stock through watermarks

Torsten Bissel, GMD - German National Research Center for Information Technology, Germany
Manfred Bogen, GMD - German National Research Center for Information, Germany
Claus Riemann, GMD - German National Research Center for Information Technology, Germany
Volker Hadamschek, GMD - German National Research Center for Information Technology, Germany

Session: Mini-workshops 1

Basically, museums have only limited possibilities to ensure their existence and to secure their funding: by sponsors, by donations, by visitors, and by selling copies of their collection in form of copyrights. While the first two (external) are almost completely out of their control, they have major influence on the visitors' acceptance by keeping their collection together, by enlarging it, and by making it attractive (internal funding). This is well understood since years. By granting copyrights to other parties and by publishing parts of their collection in the Web, museums touch the essence of their stock and they have to enter a new technology realm at the same time. Granting copyrights based on secure technology will become more and more crucial in the near future as unallowed duplication will be facilitated which will harm the museums' funding essentially.

This paper is not about intellectual property rights in general, copyright policies, or about copyright laws. We will talk about copyright technology based on watermarking. Ideally, all scans should have an integrated header information and information including author/ creator of the object, title, date, owner, copyright owner, and some usage patterns (sale or license agreements). This information has to be protected against manipulation and destruction.

Our paper starts with a description of the different approaches for embedding a visible or non-visible digital watermark into multimedia objects with focus on pictures. The feasibility of the different approaches in respect to the needs of a common museum is evaluated. After that a detailed description of various 'attacks' follows and the 'robustness' of the various kinds of digital watermarks against the forgery efforts are compared. An evaluation on currently available systems on the market and on related research projects is done next.

The ability to embed robust watermarks in digital images does not necessarily imply the ability to establish ownership. Nevertheless it is crucial for fingerprinting. Robust watermarks must be combined with hash functions and time stamping mechanisms and be embedded in a framework of trusted third parties for registration. In this third part we analyse the different demands of a copyright protection infrastructure, identify needed components and their interrelationship, and describe a system that fits a museum's needs.