Custom XMP field created by Adobe Premiere "not defined" when writing

[abarnwell]

I have a .mp4 file that I'm trying to write to a field which was created in Adobe Premiere as part of a custom metadata schema. This XMP field allows me to read it by the TAG, but won't let me write to it by the same TAG - even when I precede it with the -XMP: group name. (Hope I'm saying this all correctly as I'm a newbie)

I'm able to write to other XMP fields in this same file, and able to read this field individually using "exiftool -TAG filename.mp4". Is there some reason a field from a custom metadata schema created in Adobe Premiere's metadata panel would return "Tag 'tagname" is not defined" when trying to write to it?

[StarGeek]

Exiftool doesn't know how to write it.  As you said, it's custom.  You have to create a definition for it.  See the example config file for details.

[abarnwell]

So that explanation helped me understand the need for a custom user configuration file (which I've now created). Thank you.

While I'm now able to define a custom namespace, I'm having trouble figuring out how to exactly match the custom namespace created by Adobe Premiere in my custom configuration file so that I can write to that custom tag created by Premiere.

If the tag created by Adobe Premiere is called "AdobeTag", for instance, and that Tag (or 'Property' - as Adobe calls it in Premiere) is created under a custom Metadata Schema inside Premiere called "AdobeCustomSchema", then how do I figure out what to name the namespace in my custom configuration file so that I can address that original tag and not accidentally create a new one by the same name?

I've tried using the metadata schema name "AdobeCustomSchema" for the name of my namespace, but it creates a duplicate "AdobeTag" in the file. I can't seem to get at the original custom Tag Premiere created.

I must be misunderstanding something about the structure of namespaces and tags.

[Phil Harvey]

1. Use Adobe Premiere to write the tag.

2. Run exiftool -xmp -b FILE to extract the raw XMP

3. Look at the raw XMP to see what namespace prefix and URL are used.  And the exact tag name for the tag you want to write.

- Phil

[abarnwell]

Thanks so much!

Right before seeing your reply I accidentally discovered that if I ran 'exiftool -G1 filename.mp4' it would show me the namespaces after the groups and I was able to find the correct namespace that way. I added the namespace to my config file and was able to write to it successfully.

I'm sure your way is better - but let me know why what I did worked if you don't mind just so I know when to use it properly.

Thanks again!

[Phil Harvey]

You also need to get the correct URI (sorry, I said URL in my earlier post, but I meant URI).  You can only get this by looking at the raw XMP.

- Phil