Conformance to PDF flavours stated in XMP metadata attached to parts of the PDF

[Bertrand Caron]

Dear All,

We've come across a couple PDFs that result from a merge of other PDF files, in particular PDF/A files. As a consequence, XMP metadata containing a conformance statement to a PDF/A flavour are attached to other objects than the root object catalogue - in the case we found, to an outline item or even to individual images.

As PRONOM is searching patterns for PDF/A at a variable offset, it will pick every conformance statement in any XMP metadata section, no matter where it is attached to.

In both cases, my conclusion is that these conformance statements are irrelevant because they are attached to only some parts of the PDF. I will then resolve the issue by assigning a PUID corresponding to the version of PDF, not to PDF/A.

I don't think there is any way of improving PRONOM or DROID's behavior here, but the case was interesting and I wanted to share it with you!

Kind regards, 

Bertrand