I am investigating/experimenting with PREMIS and I am trying to
automatically generate xml documents as items pass through our
workflows via python scripts. I work in the Irish Film Archive, so we
generally handle self-digitised moving image material as well as born
digital files. I hope that you can help me with some questions.
As we handle very large image sequences (approx 150,000 TIFF/DPX files
per film), I'm curious as to how to document these in PREMIS.
1. My main question is if these sequences need to be documented as a
representation object for the whole image sequence, and then perhaps
each image in the sequence requires their own file object? This would
lead to a gigantic xml file, but I see the value in recording this
information on a file level. I notice that something similar happens
in your 'Animal Antics' example in the v3 documentation. Are there
any examples available of an image sequence documented like this? On
our regular database, we would view the whole sequence as one
object/package, and it would have one database record per sequence.
2. I also notice that objectCharacteristics is not applicable to
Representations, so I'm not sure how to document the overall file size
of the image sequence?
3. As for events, environments, agents, It would seem to make sense to
link all these to the single Representation object. I'd hate the
thought of having linking identifiers for all 150k files to a
'capture' event, or even multiple fixity check events over time.
Hopefully linking such events to the Representation object is
4. Initially I was wondering how to document fixity, as it makes most
sense to me to just include a separate checksum manifest within the
SIP/AIP. There does not appear to be a method within PREMIS to point
to an external file like this for fixity, such as 'fixityExtension'? I
suppose that this is only an issue when documenting a representation
object that contains multiple files, rather than documenting fixity
for a single file.
Any help on one or all of the questions would be greatly appreciated.