Motion Picture Film Guidance: Sustaining Moving Image Files
How Do I Best Ensure That My Digital Files Will Be Usable In The Future?
Digital preservation for any type of file involves many components, such as:
Choosing a sustainable digital format.
- A sustainable format is one that is lossless and uncompressed. Some examples for motion pictures include DPX, TIFF, Motion JPEG 2000, and WAV for audio.
Choosing a sustainable storage media.
- Sustainability may look different for institutions or individuals based on needs and available resources. Some examples of longer term storage media include Linear Tape Open (LTO), Cloud Storage, and Redundant Array of Independent Disks (RAID). Whichever storage media is decided upon will require maintenance, monitoring, will continue to incur costs for support.
Identifying recordings that you want to preserve.
- There are many factors that go into deciding what recordings to preserve. Points of consideration may take deterioration, age, uniqueness, content value, and format obsolescence into account.
Organizing files using proper file naming conventions, embedded metadata, and structured directories.
- Organized file directory structures should be consistent and make sense organizationally as well as to someone who may not be familiar with your recordings.
- File names should aim to be less than 25 characters in length, be human readable, be unique, and have a file extension that matches the file format (i.e. 342-usaf-12345.mp4). The file name should not include non-alphanumeric characters (!@#$%^&*) or spaces. (i.e. 342%usaf*12345!.mp4)
- There are a variety of open source tools that one can use to embed metadata into video files. HTML files with metadata information can also be included in a folder with the file of your recording.
Protecting your files by backing up your data, monitoring files by comparing checksums at regular intervals, and storing multiple copies (three is recommended) on different media types, and in different geographical locations if possible.
- Monitoring data regularly includes running backups.
- Monitor the integrity of your files on a regular, ongoing basis by checking fixity and comparing checksums. It is important to run a checksum when your files are first created to have accurate record to compare against.
- Keeping a copy in the cloud can be part of your strategy, but do not rely solely on the cloud as the only storage solution.
Migrating data as formats and carriers improve and/ or evolve.
- File formats evolve and change over time. This can mean that it’s easier to access and work with the files, or that it will become difficult, or impossible, to work with your files (however, choosing a robust format as noted above will help). You should investigate changes in formats on a regular basis.
- Storage devices and carriers also change with the market. For example, LTO tapes and drives are backwards compatible for two generations, so every other generation will need to be migrated to the latest iteration of tape to be retrievable.
- Be aware of the terms and conditions if working with a cloud provider and any changes that they may make to their policies.
Managing the data by utilizing an asset management system that also allows you to easily export content.
- If you have a large volume of data an asset management system can assist with the retrieval, cataloging, exporting, and transcoding of files for review and delivery. Some programs may even assist with monitoring functions and fixity checks.
Where can I find more information?
- Preserving Your Digital Memories From the The National Digital Information Infrastructure and Preservation Program, A Collaborative Initiative of the Library of Congress
- Sustainability of Digital Formats From the Library of Congress
- Keeping Personal Digital Video From the Library of Congress
- Selecting Storage Media for Long-Term Preservation From The National Archives (UK)
- Best Practices for File Naming and Organizing Files From The Smithsonian
- Metadata editing: