Single keywords not in sync on 'Get IPTC Photo Metadata' website

[Eve2]

I've generated a new image and added tags.

When I add a single keyword to both XMP-dc:Subject and IPTC:Keywords
e.g.
exiftool test.jpg -XMP-dc:Subject=keyword1 -IPTC:Keywords=keyword1
Then the Keywords field is shown not in sync [NOTsync1] on 'Get IPTC Photo Metadata' / https://getpmd.iptc.org/getiptcpmd.html


When I add multiple keywords
e.g.
exiftool test.jpg -XMP-dc:Subject=keyword1 -XMP-dc:Subject=keyword2 -IPTC:Keywords=keyword1 -IPTC:Keywords=keyword2
Then the Keywords field on https://getpmd.iptc.org/getiptcpmd.html is shown in sync [sync1].


I'm using exiftool 12.58 on Linux to generate the tags.

Since https://getpmd.iptc.org/getiptcpmd.html is powered by exiftool (version 12.5) i think this forum is the appropriate place to ask questions.

Why is single keyword shown as not in sync, and are multiple keywords shown in sync?
Is this bug in the reporting of https://getpmd.iptc.org/getiptcpmd.html of a bug in generating the tags?

Regards,

Eve2

[Phil Harvey]

I don't know what "NOTsync1" and "sync1" means, so I can't help here.

- Phil

[Eve2]

Thank you for your reply.

The IPTC standard requires/recommends for some tags that both the XMP and IIM tags have the same value.
Then they are in sync.
e.g.
exiftool '-XMP-photoshop:Headline=my headline' '-IPTC:Headline=my headline' 'test.jpg'


If they don't have the same value they are not in sync.
e.g.
exiftool '-XMP-photoshop:Headline=my headline' '-IPTC:Headline=a different headline' 'test.jpg'


This works well for all tags I have tried, except for single Keywords.
Single Keywords are detected not in sync regardless if they have the same value in XMP-dc:Subject and IPTC:Keywords or not.

[Phil Harvey]

OK. I have a theory (seeing the array index in the "Field Value" entries was a clue).  Perhaps they are using the -struct option, which would show this:

Code Select Expand

> exiftool a.jpg -XMP-dc:Subject=keyword1 -IPTC:Keywords=keyword1
    1 image files updated
> exiftool a.jpg -subject -keywords -struct
Subject                         : [keyword1]
Keywords                        : keyword1
> exiftool a.jpg -XMP-dc:Subject=keyword1 -XMP-dc:Subject=keyword2 -IPTC:Keywords=keyword1 -IPTC:Keywords=keyword2
    1 image files updated
> exiftool a.jpg -subject -keywords -struct
Subject                         : [keyword1,keyword2]
Keywords                        : [keyword1,keyword2]
In the first case (1 keyword), the entries are sync'd properly, and a single-element XMP list should be considered the same as a single IPTC value.

- Phil

[Eve2]

Good theory.

I've viewed the ExifTool documentation and I see that the -struct option works for XMP information and this explains the difference between XMP-dc:Subject and IPTC:Keywords.

Thank you.