[XeTeX] XMP and XeTeX

[Gareth Hughes]

Dear friends,

A few people have been asking about tagging PDFs with XMP metadata.
Currently, this seems not to be all that straightforward with XeTeX.
There are a couple of packages that assist with the task under PDFTeX:
hyperxmp and xmpincl. Of these, I think hyperxmp is the more elegant, as
it doesn't require the user creation of a separate file for the
metadata, but gleans it from the PDF strings passed to hyperref.

I've had a message back from Scott Pakin, who created and manages
hyperxmp, who believes that it would be possible to get hyperxmp working
from XeTeX, but only so that the XMP tags would be visible to PDF-aware
readers. To be able to make XMP tags available to generic XMP metadata
displayers, there would have to be a way to allow xdvipdfmx to generate
an uncompressed and unencoded PDF stream.

I think it might be useful for hyperxmp to be able to work with XeTeX,
but, if it's only making metadata available to PDF readers, it is doing
little more than hyperref already does (except it would encode copyright
licensing material for the document). Further than this, what do the
more technically minded among us think about the possibility, or lack
thereof, of more fundamental support for XMP metadata?

Thanks,

Gareth.