How do I export CD Markers so players can see it?

I have a recording of a monk chanting the Buddhist Monk Rules so pronunciation can be mastered.
The original is 1hr 15m and the shrunk one which came out great at 55 minutes.
To navigate, I have 5 or 6 cd track markers which I created and labeled.
I did the export, but I don’t see these markers in the resultant file.

Do I need to export the ranges as separate files?

I left the world in the late 90’s I’m not sure how music works after the CD age.
What I envisioned would be a single 50mb file (medium) mp3, and somehow there would be markers showing up in vlc.

I looked at the Ardour manual for making CD Markers and I made them… but I’m left with “Now what do I do with those markers?”
I saw another post here which seems really technical. It might just be easier to manually export separate mp3 files from ranges based on what I read.

Perhaps I’m dreaming and that is just not how things work?.
I want a single file with subfiles inside. Tracks are ambiguous for ardour and searching because it means well… tracks as in multi-track… not “chapters” or “songs”.

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So CD Markers are generally used for burning a CD, don’t think there is an easy way to incorporate them from Ardour into chapter markers for MP* playing at this time. So yes you are probably best served by just creating a couple of MP3 exports (If that is your final destination) at this time. There is probably a couple of tools you could use to convert the TOC or CUE files into the metadata to embed in the MP3 file for chapters after export, but I don’t personally know of one off hand, just not something i have had to deal with.


It looks like no matter how you slice it, I need to make separate files and then work from there. I’m not really sure what CD markers does for anyone, other than being bookmarks.

It would be good if there was an exporter that could do this all at once.
(or am I missing something). Audacity seems like it can do this… but I will probably do this manually in ardour or ffmpeg (see below) since there are maybe 8 or 9 chapters to make.

It seems that the keyword that I need to search is “make chapters for audiobooks mp3” even though this is not really an audio book, but it sort of is a “rule book”.

After searching a bit… I decided I was not getting anywhere and asked chatgpt.
I will try to follow this instruction this weekend.

If the Ardour team is looking for new features to implement and attract new market share, audio books and larger file management might be useful. I stay away from audacity as a recording medium because you cannot change things “after the fact”. (that was how I found ardour after I realized I couldn’t change something in audacity).

In short… it seems like audacity can do this for me. But I will check later this weekend and report back. There is also a way with vlc but I have not had much luck using it as an encoder in the past.

They are extremely useful for making CDs! I have used them frequently.
The markers go into a separate TOC or CUE file during export. They are not embedded in the audio file, because tools for making CD masters or burning CDRs don’t work that way.

Don’t expect them to be useful use for any other purpose.

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There are two separate issues in this topic, related but not intrinsically tied together.

The first is whether the file format supports any kind of marker in the metadata.
The MP3 file format is very ancient and does not support markers (nor gapless playback and other features that modern codec/container combinations do support).

I believe that the mpeg4 audio files which are usually labeled as .mp4, .m4a, or .aac files support markers. For use with free/libre software solutions the Ogg container format which is typically used with Vorbis or Opus audio data supports chapter markers.
Chapter extention for VorbisComment tags

The second issue is how to get track markers within Ardour exported as metadata markers in your format of choice.
That is not something I have personally done, but according to this page of the manual it looks like if you export with the checkmark for chapter markers for MP4 files created, it should do what you want:
Ardour manual export format profile page

I do not have access to a machine with Ardour at this minute, so I cannot check whether that forces you to use Apple Music export profile, or if you can use other codecs. I would expect that it would be specific to MP4 files based on the name of the option, although also based on the name it seems that it makes a file with chapter marks, so it is not clear how you make use of that file.

What type of file you use may depend on how many different types of playback devices or software you wish to use. You mentioned VLC, which supports nearly every file format, so should no be a problem no matter which codec and container you choose.

If the export dialog does not have options for creating the appropriate metadata, my first inclination would be to generate a WAV file and CUE file from the CD export setting, then make a script to convert the CUE file track entries into chapter entries in a comment file for an ogg or opus file, and call oggenc or opusenc as appropriate to encode.
That is basically what Ardour does behind the scenes (although probably using ffmpeg), so a lot of the pieces probably already exist to do what you want.

I would start by looking through the options for generating mp4 files, there may be a combination which already does what you want.

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Great answer. I will try later this weekend.

I tried a quick test tonight, and it appears that none of the existing output formats indicate in an easily seen way whether a cue or chapter file will be created.
You can select an export preset and use the “Edit” button to see what options are selected, and strangely even the CD export preset does not generate a cue file to use for creating a CD with track markers.

So you can select the “New” button to save your own export preset, pick the file format you want (uncompressed WAV file, Ogg/Vorbis, Opus, FLAC, etc.), and select to generate a cue file, an MP4 chapter file, or both. The files will not be automatically tagged with the metadata, you will need to use an external program to merge the data regarding marker location with the audio file metadata.

The chapters file format is very simple, and is this form:
00:00:00.000 Intro
00:00:00.000 mark1
00:00:05.045 mark2

The cue file format is more verbose and has this form:
REM Cue file generated by Ardour
TITLE “session”
FILE “test_export_session.opus” Ogg OPUS
TITLE “mark1”
INDEX 01 00:00:00
TITLE “mark2”
INDEX 01 00:05:03

This was from a session where I added two markers to the CD Markers area, then moved the Start location marker to coincide with the position of the mark1 marker. I think if I had not manually moved the start marker, the postion of mark1 would not be at 00:00:00 but would be at some amount of time after 0.

So not a complete solution (i.e. directly generates a file with chapter markers) yet, but hopefully enough to get you started.

I also did a test as well with flac and red cd and it does not work with any format… or … vlc does not show chapters that exist. But I doubt anything is there.

I guess the format that I want to export to is m4b, although I did not download that format from vox , etc to test just yet. There is a program called m4b baker, but you need python qt 4 in order to build and run it and av linux has qt5 (hint)… There is a script somewhere that can merge with ffmpeg.
chatgpt swears on the holy bible that I should be able to select export chapters while making m4a. It says I have something wrongly installed, but that is not true.

I use the CD markers when exporting to Red Book format all the time. After that, a GUI tool like k3b, or CLI tool like shnsplit, makes quick work of converting the WAV/CUE pair into multiple audio files.

I’d be really surprised if you could find audio players that make use of BWF cue / cart chunk metadata anyway - they’re in common usage in broadcast automation systems, but very rare anywhere else. I wasn’t aware of any other standards for cue metadata within audio files, but Chris’s suggestions around mp4 look great.

What exactly did you test, and what do you mean by “does not work with any format?”

You either left out a lot of steps that you performed, or you completely misunderstood what I wrote earlier and did not perform the necessary steps.
Did you create a new preset which generates a cue file and/or an MP4 chapter file?
Did you then convert the markers from one of those files to appropriate VorbisComment chapter markers?
Did you then use metaflac (or some other tagging tool) to embed the comment metadata into the FLAC file?

I just made a test file to check, and VLC does no seem to parse VorbisComment metadata in FLAC files. That surprises me a little, VLC usually has pretty thorough file support, but maybe that extension never became widely used.
I will try to check using faac and fmpeg to create an mp4 audio file later, that format should be more likely to have chapter support.

My file has the cd markers (8 or 9).
The only other work I did was export different files and then try to run it on vlc.
It would be useful to download a vox and see if chapters are really showing in vlc.
They should show up.
I’ll probably use an ffmpeg script . I might redo the markers in audacity and then ask to split them, or go direct with ardour. Perhaps everything is indeed working but vlc. So best to find a small audiobook with 4 chapters as a test.

VLC does observe chapter markers in MP4 audio files.
This is the MP4 chapter file exported by Ardour:
00:00:00.000 Intro
00:00:00.000 mark1
00:00:05.045 mark2

I assume “Intro” is a default entry, it did not correspond to any marker I manually set in the Ardour timeline.

The format which ffmpeg expects is a general metadata file, you can find in the ffmpeg documentation about using the beginning of the file to set a title, probably author information and similar.
The file requires ending values for chapters, and I found a page which stated that the ending must be before the beginning of the next chapter, so I just manually made end times which were the start time of the next chapter minus 1 millisecond:


title=Chapter 1

title=Chapter 2

I then encoded the file and added the chapter information with this command:
ffmpeg -i test_export_session.wav -i test_export_session_metadata.txt test_export_session.m4a

When I played the test_export_session.m4a file in VLC I could jump to the beginning of a chapter using the Playback/Chapter menu entry.

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