Tuesday, April 16, 2019

International Federation of Film Archives: Survey on Long-term Digital Storage and Preservation

Digital Statement PartV Survey on Long-term Digital Storage and Preservation. CĂ©line Ruivo and Anne Gant. FIAF Technical Commission, International Federation of Film Archives. April 2019.
    The sustainability of digital files and formats for long-term preservation has been a major concern in this field for almost two decades now. The FIAF Digital Preservation Principles, published in 2016, use the OAIS (Open Archival Information System) Model. Increasingly, film archives are publishing their own technical specifications online. Digitizing a film includes not only archiving a final result (the master), but also archiving the “raw files” which are uncompressed. Some of the results of the survey of 16 institutions who responded:
  • DPX is the main format used for preservation: 14 archives
  • TIFF is used as a second preservation format: 4 archives
  • Most use 4K resolution when they scan 35mm negatives for preservation 
  • Few have written technical specifications for the deposit of new digital acquisitions, which are mostly born-digital films.
  • Some archives use lossless compression for long-term preservation of a master to reduce storage space 
  • Some archives are considering implementing the FFV1 format this year for storing files. 
  • A checksum called framemd5 is integrated with the files MKV/FFV1.
  • The recording back to film of restorations is applied by 8 archives

Sound
    In terms of sound, digital formats are more variable than image formats, depending upon their
final distribution (cinema or TV broadcast). RAW formats are usually the same as the restored
files.
  • Most of the archives use a tape system for long-term conservation. 
  • They generally wait for 2 generations to migrate their data to reduce the cost 
  • Access storage is by a server that allows direct access to the files.
  • Most of the archives store and manage their files in their own facility. 

Conclusion
     This initial survey of the current digital landscape shows there is much more work to be done to get a global view of digital film archiving, and to hear from more archives at all stages in the development of digital workflows. Some conclusions that can be drawn from the current set of responses:
  1. There is a stabilization in language and a conceptual clarity emerging about the stages of a digital workflow within archives. The terms are becoming clear and are recognized as necessary parts of daily archival practice. This will allow for better information exchange and better comparison of workflows.
  2. There are some choices which seem to be predominant, such as 10 bit Log DPX, for example, or the use of ProRes, LTO, .wav files, etc. It is helpful to detail the reasons why certain archives chose uncommon formats or processes.
  3. There are reasons behind each archive’s choices, which make sense at the given moment. But it would be useful to revisit this survey in 5-10 years (or sooner), and see how digital film practices and archiving are progressing.