Digital Copyright Protection

Citation

Pang, R. (1998), "Digital Copyright Protection", Asian Libraries, Vol. 7 No. 6, pp. 147-149. https://doi.org/10.1108/al.1998.7.6.147.11

This monograph describes various technical alternatives for protecting digital copyright material from data pirates. Although its primary audience is programmers and cryptographers needing a thorough understanding of different algorithms, it will be of some interest to information managers seeking a high level overview of relevant issues.

Commencing with two pages of preface and book notes, the core text comprises eleven chapters in three main classes: general cryptography techniques, specific approaches to copyright protection and commercial products. Chapters 1‐3 explore the notion of defending copyright in an age of cheap and easy digital copying, cryptography, and subliminal signatures. Chapters 4 to 11 examine compression, error‐correcting and tamper‐resistant codes, software and hardware solutions for locking data, white space, mimic functions, modification of image pixels, grouping selected bits to hide them, and wave technologies (for manipulating audio and visual data). Chapter 12 describes four commercial products: Digimarc (an image watermarking system), Stego and EzStego (for hiding image information on a Macintosh), and Stools (for hiding bits of audio and image files).

In consideration of some of the legal ramifications of the ease of replication, there is a discussion of the need to balance the freedom of artistic creativity with technological protection measures (Chapter 13), then in Appendix A (Permission) a fascinating 14‐page Question and Answer session with two intellectual property lawyers from New York (but those readers seeking more should consult Bernard Galler’s Software and Intellectual Property Protection). Appendix B contains a list of 14 short but relevant patent descriptions selected from IBM’s free patent search site on the Internet (all but three concerning video copy protection). Appendix C, a highly focussed 61‐entry bibliography, recognises that for a more in‐depth understanding of cryptography, and especially in respect of error‐correcting codes and compression algorithms, other resources must be consulted. Finally, there is a five‐page, two‐column index.

Comprehensive in subject scope, well structured and in parts extremely detailed, this work avoids becoming a totally abstruse technical exegesis by commencing each chapter with a humorous anecdote. Clear language in single‐column text is interspersed with relevant diagrams, formulae and charts (albeit in monochrome), and there are frequent asides in smaller italicised text in the outer margin.

In terms of limitations the most significant are that the assessment of commercial products is restricted to image software, and that there is minimal discussion of the Internet and emerging encryption key ownership issues. Furthermore, there is an implicit overwhelming presupposition that the protection of individual intellectual property is valued worldwide ‐ a situation which is certainly not the case in all societies. Despite these drawbacks, Wayner is a welcome resource for students seeking to understand fundamental data protection techniques. It is certainly a convenient guide for programmers contemplating the responsibility of defending copyright digital material. However, it is of limited use for information managers wanting to evaluate specific tools to protect their digital software products or for librarians interested in the wider sociological issues of copyright protection.