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Studies FY2004

The themes of studies FY2004 are as follows:

(1) Migration of packaged digital publications

As digital media become obsolete, it becomes difficult to access recorded data. To avoid this problem, periodical data transfer to other media (migration) is needed.
We attempted to transfer the sample CD-ROMs held by the NDL to hard disks using a commercially available migration program. Though virtually all the materials were converted successfully, some were not because of copy protection. As the file formats created on a hard disk are specific to the migration program, problems can occur with the long-term usability of digital materials after migration.

(2) Emulation of packaged digital publications

Even if a digital material has been preserved in a proper way, it is unusable on a new PC when the structure of the data depends on obsolete PC or OS. To use software designed for an old PC on a new one, an application called “emulator” which can artificially recreate the operating environment of an old PC (“emulation”) is needed.
Playback tests on a PC with a new operating system were conducted on the samples from the digital materials that were created as a result of the migration described above (1), using a commercially available emulator. Only about 30 percent of the materials tested could be played perfectly.

(3) File format conversion and ensuring long-term accessibility

Obsolescence of file formats, as well as that of digital media, makes it difficult to read the data.
100 digital materials were selected as samples from those containing only data. For 15 of them, whose file format can easily become obsolete, we tried to convert the format to a commonly-used one. However, only two materials were playable in this way.
There were some materials whose application program necessary to reproduce the data was already generally unobtainable.

Results of the studies are summarized in the “Study Report on Ensuring Long-term Preservation and Accessibility of Digital Information”.

“Study Report on Ensuring Long-term Preservation and Accessibility of Digital Information”, March 2005


  1. Introduction
  2. Study report
    • 2.1: Purpose
    • 2.2: Outline
    • 2.3: Migration to hard disk
    • 2.4: Playback testing
    • 2.5: Discussion
  3. Conclusion

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