A) Three IIM fields 2:10 Urgency, 2:15 Category, and 2:20
Supplemental Category are represented in, and synchronized with,
photoshop:Urgency, photoshop:Category, and
photoshop:SupplementalCategories by Adobe today, even though they
were not adopted in the approved IPTC Core schema for XMP. They are
listed as deprecated. But they are "still synchronized with the XMP
property", ... "hence available for future use -- but outside the
IPTC Core."

If the IPTC use definitions are consistent with these photoshop
fields, then might it be prudent to specify the photoshop namespace
fields instead of defining three new Iptc4xmpIIM namespace fields?

At least the implementation note for each should make reference to
this past assignment in the photoshop namespace.


B) Content Location - Since alignment of Code and Name is required in
the IIM implementation, I suggest that this dictates an XMP bag array
structure to maintain the alignment.

Iptc4xmpIIM:ContentLocation bag ContentLocationDetails (structure)

ContentLocationDetails (structure)
Code Text
Name Text


C) Reference - 2:45, 47, and 50 are repeatable in "sequential
triplets" in IIM. I suggest that this dictates an XMP seq array
structure to maintain the alignment of the triplets.

Iptc4xmpIIM:Reference seq ReferenceDetails (structure)

ReferenceDetails (structure)
Service Text
Date Date
Number Text


D) XMP property id choices - The cryptic XMP property id "IIM2-003"
for "2:003 Object Type Reference" , for example, runs counter to the
practice used in IPTC Core where the XMP property id "SubjectCode"
was used for "2:012 Subject Reference". I suggest that the property
id be formulated from the property name, not its IIM encoding
assignment.


E) 1:90 Coded Character Set -- IIM has a rich set of choices for
this property. Unfortunately, the (typical) absence of this metadata
property means "default system character set" which varies on
different platforms. XMP is only implemented in UTF-8. The platform
interoperability benefit that XMP offers is an important motivation
for defining this schema. It warrants mention in the introduction.

F) Appendix: Mapping of all IIM properties -- It would be useful if
the twenty IPTC IIM properties that are missing from this table were
added with "Not mapped, not relevant"