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The Long-term accessibility of packaged digital publications (NDL Research Report No.6)

Recording media and suitable playback equipment are needed to use digital information. However, the lifespan of most recording media is said to be about 20-30 years even if they are preserved in a proper environment. It is also said that the lifespan of playback equipment is much shorter. Furthermore, standards for playback equipment and media change so frequently that it can be difficult to obtain items whose standards have become obsolete. Packaged digital publications typified by CD-ROMs are records of digital information on recording media, and various problems arise when using them.

This report is a summary of results of studies conducted in FY2003 and FY2004 in which the usability of packaged digital publications, such as CD-ROMs, was investigated. In FY2003, a study was conducted to test the usability of digital publications in what was then the latest PC environment (Chapter 2). In order to solve the usability problems revealed in the FY2003 study, two methods which have been thought to be solutions to long-term preservation, namely migration and emulation, were tested, and the results were evaluated in FY2004 (Chapter 3).


  1. Introduction
  2. Results of FY2003 Study
    • 2.1: Stock survey of packaged digital publications
    • 2.2: Usability study
    • 2.3: Analysis of test results
    • 2.4: Detailed analysis of factors preventing use
  3. FY2004 Study
    • 3.1: Purpose
    • 3.2: Outline of Study
    • 3.3: Migration to hard disk
      • 3.3.1: Migration trial
      • 3.3.2: Time required for migration
      • 3.3.3: The effects of technological factors on migration time
      • 3.3.4: Discussion
    • 3.4: Playback testing
      • 3.4.1: Emulation and file format conversion
      • 3.4.2: Emulation playback tests
      • 3.4.3: Playback tests using file format conversion and a multi-file viewer
      • 3.4.4: Review
    • 3.5: Copy protection and metadata
      • 3.5.1: Copy protection
      • 3.5.2: Metadata
  4. Conclution
  • Appendix 1 Examples of emulators
  • Appendix 2 Examples of conversion programs

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