macOS: When moving files (in MBP), how does target directory "know" it's a media directory?

I already asked this on a couple of macOS forums but no-one seems to know. I now ask here because when MBP moves files to another directory, that directory somehow “knows” it’s a media directory.

Some directories seem to “know” they contain media files, others don’t. I am not using iTunes/Music (app) btw.

For some directories, in Finder, List-view, when I click on the headings, I can add extra columns such as Album and Genre - let’s call those “media columns”.

However when I created a new (test) directory and placed some mp3 files inside it, then right-clicked that directory’s headings, no options to add media columns were given. These mp3 files did contain ID3v2 metadata btw (I don’t know if that’s relevant).

What is it that distinguishes / determines these two types of “add column” behaviour? Different kinds of directories? If so, how does one change it?

Again, I ask here because nsomething that MBP does when moving files seems to make the target directory “know” it’s a media directory. And no-one on two macOS forums seemed to know.

Apologies for the blasphemy by mentioning “the others” but when a Microsoft OS does this it is just looking and taking a guess based on files it see. If lots of MP3s, then music columns. If lots of JPGs, then picture columns, if mixed, then normal columns.

In the Microsoft world a poke at the Properties of a folder reveals a Customise tab that lets it swap the type of folder. So have a poke in your Mac’s folder properties as the systems can sometimes be more alike that we release.

This is nothing MBP does. It is all down to Black Magic in the host OS.

If you like hacking the hidden black magic - turn on hidden system files and look for the .DS_Store files as these are part of the answer…


Actually Picard does nothing special here, it just moves files and creates ordinary directories on demand.

I also don’t know how macOS decides this. Maybe based on the file types inside the folders? As macOS itself has limited support for media files maybe only specifically supported file types trigger this behavior?


Thanks for those replies. So it’s OS black magic then.
The suggestion of looking at [.DS_Store] files hadn’t occurred to me - though I’m not clear what to do with them - a whole other layer or two of studying required.

I have one folder with about 350 mp3 files, most with ID3 tags, some without, also has folders with further mp3’s. One of the folders below it has six mp3’s (and nothing else). Neither of these folders offers music-type columns.

In another folder (on same disk) is a folder with 16 mp3 files, no ID3 tags, but here the music-type columns are available.

Bemusing! I will have to go back to various macOS etc. forums then.
I’ll report back to here if I ever find the answer.


Special Apple magics. :mage:

Identification could be biased by the bitrates of your MP3s or what they were ripped by (i.e. if you dare to have non-Apple rips they may be treated different to iTunes rips).

Or when the folder is made the first items into it may set its personality.

I’ve never watched the Microsoft Magics that close as I know it is easy to change. The parent folder will often bias things. Just like on the Apple where there are set Music and Pictures folders within the OS, make a sub folder in that tree and it follows the parents.

I bet if you copy that folder with 16 mp3 files to a new location and change the music in it the columns will stay as music. I’d expect the style to follow the folder, especially after having a quick read of what the .DS_Store file is.


The pragmatic explanation/solution seems to be that the folder name has to start with "Music’.
Doesn’t matter where it’s located. In my case my music is on an HFS+ formatted external disk.

So e.g. it works for “Music”, “Music Test”, “Musicbhuexnihuewc” or whatever.
But it’s case-sensitive, so e.g. doesn’t work for “music” or “MUsic”