When ripping an album in multiple formats, it's convenient to add metadata on one version of the album, and then copy/paste the tags to the others. This works very well as long as all the formats have the same channel layout. However, if I copy tags from a 5.1 album to a stereo album, the stereo files get marked "Channel layout: L R C LFE Lb Rb" in MediaInfo. How can I prevent this from happening?
Is the channel layout information from the file header or a user-defined field in the tag data?
I have no idea, it's automatically there when converting with a FLAC tool. Here's an example 4.0 file: Gofile - Free Unlimited File Sharing and Storage
I see a tag field
WAVEFORMATEXTENSIBLE_CHANNEL_MASK
in the extedned tags dialogue.
that Foobar does not show - but it shows channels:
and after I copied the tags from the flac file to an mp3 file, the tag fields stayed the same in MP3tag:
But the technical description in Foobar changed:
so that Channels are now 2.
but Foobar now also shows the extra tag field as MP3tag.
So: I would just delete the field WAVEFORMATEXTENSIBLE_CHANNEL_MASK.
I don't know if this is something that should be dealt with in the program as special information as apparently some programs evaluate this special field to be technical information and not a user-defined field.
Deleting the field works when copying metadata from 5.1 to stereo, but not the other way around, as I'd like to keep the layout consistent in case it matters for playback. Ideally Mp3tag would just ignore this field entirely when copying, but at least now I know how to fix it. Thanks.
Thanks for posting this, as it helped me resolve the problem I was having when copying tags among mono FLACs: Mp3tag was copying channel layout data I actually wanted to get rid of. However, I can see how sometimes you might want Mp3tag to preserve that data, so I don't consider the default behavior undesirable.
To better explain:
WAVEFORMATEXTENSIBLE_CHANNEL_MASK is typically used in lossless multichannel files to say what channels are present. I often find it in mono files, too, depending on how they were made. The mask values are defined by Microsoft, with
0x1 = Left
0x2 = Right
0x4 = Center
and so on; you add the values for each channel that's present, e.g. a stereo file could have 0x3.
If the value is not given for a single-channel file, players should default to center. That's what I want for my mono FLACs, so I just deleted WAVEFORMATEXTENSIBLE_CHANNEL_MASK entirely from the extended tag panel in Mp3tag. Alternatively, I could've set the value to 4.