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Downloading DROID Format Records
 | NOTE that this page dates from around the DROID 5 release. There's some useful info, but needs updating. |
Droid and Pronom
Many of us have used Droid
or Pronom in our work. This page includes some ideas and resources that may be of use to understand them better - or even make better use of them.
- Service to retrieve the current signature file: http://www.nationalarchives.gov.uk/pronom/service.asmx
- When you run Droid, it will place a copy of the current signature file in ~/.droid/signature-files
- The signature file contains information on all of the formats that Pronom knows. The signatures, however, have been compiled into a format that makes it easy to apply, but hard to understand. The following script will fetch the full XML documents for each format and place them in a subdirectory called xml.
The result of executing this Bash script is attached below.
Thoughts
- Droid 5 is much faster than its predecessor, but it appears to slow down with each file it scans. After a couple of thousand, it can get quite slow. I believe that this is because the GUI does not scale well.
- Droid 5 has a command-line mode, but unfortunately, the implementation intertwines the GUI with the command-line tool. As a result, the command-line version is slow to start and exit. This can be OK when using it to process a large number of files, but it means that it can't be used as part of a script or automated process.
- The core routine to match a file against a signature appears to be unchanged from Droid 4.
- It should almost be easy to implement an efficient command-line matcher.
- There has been a lot of effort put into developing the GUI and less into developing the signatures. Pronom lists over 700 file formats, but has signatures for only 245 of them.