Tagging Flac Files and Field-Name Letter Casing

Greetings, all, I am new here, and am glad I have found place where I hope I can get some help.

I have been using mp3 tag a while now to edit and tag my flac files.

I have two questions about this;


I noticed and this has always kind of bugged me, but have not known how to deal with it. Whenever I edit a tag for a song such as a the title of a track on a flac album, I find that the field-names seem to be converted to all caps. So if I had edited the title of a song from a flac album, then the filed-name for the track title changes to all caps.

When I hover my pointer over the individual flac files or songs in flac format, in windows, I will see the capitalized field-names after I had edited the tags.

To work around this, I would do all my editing to individual songs or tracks, then do my edits for the whole album. Then I would run a case conversion to Mixed capital letters to undo any capitalization of filed-names after my edits.

Is there a way to stop mp3 tag from doing this? since that extra step is quite tedious when I have hundreds of albums to edit.


In addition, there are times where I want some field-names in all caps, such as for an album's UPC code, When I do my whole album case conversion to mixed cap letters, I would like to l keep the UPC, and IRSC field-names in all caps while keeping all the other filed-names in mixed caps or the first letter in caps, if that makes sense.

There are several threads about this questions, just have a look at the search in the upper right corner.

One of them includes an answer from the developer from Mp3tag:


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Just noting in case that is not known: The field names for Vorbis tags (as used by FLAC) are by definition case-insensitive, so "artist", "Artist", "ARTIST" or even "aRtIsT" should be considered all the same field.

But as not all software handled this properly it has become kind of the standard for tools to write the tags all uppercase. If you want best compatibility I'd recommend staying with uppercase field names. Or if you don't at least remember that this might be the issue if some software or device has trouble reading the tags in your files :wink:

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Ok, I saw the link to a previous thread, and tried it.

I went into the view tab > Customize Columns, from here I do not see a field-name among all the others, so do I add a new column and then add in; %Fieldname% to get it to show how I want it to?

Edit, I tried this, and it did not work, is there something I am missing here?

If you want to see a new column with the content of the field with the name "Upc", you have to add it in exact the same way you want to write it back into your files.

For example, if you want to write back the tag field name (not the content!) in all UPPERCASE letters, you would define the new column with the value and field: %UPC%

A new added UPPPERCASE tag field name ISRC would look like this:

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Thank you for this, this helps somewhat. But how do I get mp3 tag to not capitalize all the rest of the field names?

Do I go through all the rest of the tag elements in those columns, and specify what case I want them in with the percent signs on either side for them all? like in the screenshot just shared?

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There are two different cases:

a) If you look at the tag field names with ALT + T you will always see them in UPPERCASE. There is no hint, how these tags are currently written in the files

b) If you define your columns by yourself, you can specify the syntax as you want.

But - as @phw already wrote - the definition is case-INsensitive. If you change it, probably 3rd party software can not read it properly anymore. So please be careful changing them.

Ok, thank you for taking the time with the screen shots. Maybe I will just leave the rest alone and just ad in the UPC and IRSC as shown here, and leave the rest alone. I will then just have to do a case conversion of everything after I edit like I have done.

If I just do those column elements, will that make them less readable?

My main concern is the ability of different things being able to ply back my files, and if it means just handling the tags like I have been doing, I will, I do not want to break anything.

So far, I have the filed names of all my flac albums set to mixed capital case, with some things like the UPC in caps. Will this affect the compatibility of my files?

I have hundreds of albums in flac set up like this, should I go back and change the filed names of them all to all caps? that would be a huge and tedious project.

Mp3tag does not touch the audio part of the files. As long as you do your changes inside Mp3tag, you can not break the song (audio part) itself.

If you try to change the Letter Casing of tag field names, Mp3tag will still read them. For other software I would not guarantee it.

If you don't have a very specific need to change the tag field names - we still don't speak about the content, right? - then I would leave them unchanged.

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Should I go back to all my other flac albums and change the filed-names of them to all upper caps? or just leave them as I had set them up, which was with mixed or capital case lettering, with UPC in caps?

If you don't have any problems displaying the existing metadata in your applications and devices, I would not change the tag field names.

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@missmusic I agree with this approach suggested by @LyricsLover . There are far more issues that could arise from attempting to change the case of the field names than it may be worth. These are purely cosmetic and have no bearing whatsoever on the actual content, which of course is far more important. As you have noted, different programs that write the information handle the field case in their own way. And even if you use mp3tag to update these once, there is no guarantee that they will stay that way if you use any other program afterwards.

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Ok, thanks all, yeah, it will be too much work for me, I will continue as I have going forward with maybe adding in the new things I was shown a little earlier in this thread. My main concern is that the songs and albums are as compatible with as many playback devices as possible.

This is exactly right. None of the field names ever appear on any player anyhow, only the contents.