My digital photos have been spread out over numerous devices in a completely disorganised mess, and I'd like to finally organise them. However, I am struggling to determine what the best way to go about this would be without tying myself to a particular app or service. (I.e. I can open my library with any gallery / viewer app and it would be organised with whatever albums, tags, faces etc that I had set up previously. Similar to how I can with my music library)
I know of XMP files, but I'm not sure what fields they accept, or what applications will actually read each field. Trying to read a list of fields it seems like each app uses its own set of fields, and albums don't even seem to be a feature.
Is there something I'm missing? Or are photos and videos not like music files with relatively universal metadata?