Labels to id3v2 mp3 chapters spec

[vxm]

When I export to MP3, I would like labels to generate id3v2 chapters. Podcast listening applications like Overcast use these for listeners to skip to topics within a podcast they wish to listen to.

http://id3.org/id3v2-chapters-1.0 is the link to the spec.

There are apps which allow the import of a cue sheet and convert them to id3v2 mp3 chapters, such as https://chaptersapp.com/index.html - but it would be much more useful to be able to create the labels in Audacity while editing and have the chapters created as a part of the export to MP3.

[steve]

Are there any players that support ID3v2 chapters?

[vxm]

Are there any players that support ID3v2 chapters?

Yes, there are.

MP3 chapter markers are supported by most podcast clients, including Apple Podcasts on iOS (provided you're on iOS 12)

Under iOS and OS X, chapter marks in MP4 files (with URLs and images) are generally well supported by most podcast players, for example in Apple's Podcast app. MP3 chapters can be displayed with Instacast, Overcast, Castro, Downcast, Podcat, Pocket Casts and iCatcher!.

On Android you can use Podcast Addict, which supports chapters in all file formats (MP3, M4A/MP4, Opus, Ogg, etc.), uPod to display chapter marks with URLs and images in MP3 and MP4 files, the open source AntennaPod supports chapter titles with URLs in MP3, Opus and Ogg Vorbis files and Pocket Casts supports MP3 chapters.

[steve]

I don't have a smartphone. Any PC apps support ID3v2 chapters?

[vxm]

Chapter image and title in Ubuntu's media player



QuickTime player supports previous and next chapter based on these markers. It used to give a list of the chapters with their names, but Apple removed that interface at some point.

Chapter overview in iTunes


VLC is reported to, although I haven't tried.

[vxm]

https://github.com/podlove/podlove-publisher has a web interface which also supports id3v2 mp3 chapters.

[vxm]

It also works in https://www.podigee.com/en/podcast-player/ Podigee's web player (there's a chapter marker button that reveals them in their interface, the button to the left of the cloud icon)

[steve]

It also works in https://www.podigee.com/en/podcast-player/ Podigee's web player (there's a chapter marker button that reveals them in their interface, the button to the left of the cloud icon)

I downloaded the MP3 from there, but I don't see any chapters in the downloaded version. I've checked with MediaInfo and VLC. Do you see chapters in the downloaded MP3?

While it's encouraging to see that some apps are taking up id3v2 chapter tags, it still seems a long way from being "mainstream", especially on Windows (our main user base by a long way). If we did add support for writing chapters, we run the risk of being flooded by users complaining that it doesn't work (on their media player).

I can certainly log your "vote" for adding this feature, but I also have concerns about how useful/frustrating it will be to the majority of our users.

[vxm]

Is a screen grab of mp3 chapters in VLC on Windows, taken from the Internet. I'm still working out how to view them in VLC on Mac OS.

I'm led to believe that VLC, Windows Media Player (supports chapter images) and also Ubuntu's default video player (supports chapter images and titles) all should work. I'm trying to confirm that.

But I wonder: the Windows user base of Audacity creates files for -their- audience, and focusing only on what Windows support exists may be in error. What are their users using, and who are they producing for? It's probably more diverse, consisting of mobile (iOS, Android) if they're producing podcasts.

It's been a part of the spec since 2005. Enough clients support it, especially on mobile, that I'm getting asked regularly by the listeners of the podcast that I produce to adopt chapters. They allow listeners to find specific parts in a media file they are interested in and make my podcasts more likely to be discovered by new listeners. Some tell me that they don't want to listen to podcasts that don't adopt chapters, having experienced them.

I can't speak to the podigree file, but I produced this one last night which does work in Overcast, and should work in other players that implement the spec. http://www.podtrac.com/pts/redirect.mp3 ... destri.mp3 - I edited the file in Audacity, created the labels in Audacity, exported the labels as txt, and then paid for credits to Auphonic.com to use their tool to take the txt file and add the labels as chapters to the mp3 file. (Auphonic does a lot of other things, like level gain, noise reduce, and so on - but all I needed it for in this case was embedding the labels as chapters, because Audacity doesn't.

ffmpeg -i FILENAME should confirm the file has added chapters. I downloaded MediaInfo to see what you're seeing - MediaInfo does not appear to display the chapters, but I have verified that I can see them using FFmpeg.

In the file linked above, the FFmpeg -i output is:

Code: Select all

Input #0, mp3, from '/Users/vmarks/Downloads/ai pod/05092019 ai podcast.mp3':
  Metadata:
    title           : Blondie, Steve Jobs, Jimmy Iovine & Jimmy Destri
    encoded_by      : auphonic.com
    artist          : AppleInsider Podcast
    date            : 2019
  Duration: 00:32:35.71, start: 0.025056, bitrate: 112 kb/s
    Chapter #0:0: start 6.919000, end 63.220000
    Metadata:
      title           : Opener
    Chapter #0:1: start 63.220000, end 642.801000
    Metadata:
      title           : Introduction: Jimmy Destri
    Chapter #0:2: start 642.801000, end 725.750000
    Metadata:
      title           : I know music, and I know addiction
    Chapter #0:3: start 725.750000, end 839.764000
    Metadata:
      title           : Analog synths to digital and laptops
    Chapter #0:4: start 839.764000, end 896.441000
    Metadata:
      title           : Garageband
    Chapter #0:5: start 896.441000, end 963.603000
    Metadata:
      title           : Today, anybody can make a record
    Chapter #0:6: start 963.603000, end 1057.966000
    Metadata:
      title           : iTunes really covered our asses
    Chapter #0:7: start 1057.966000, end 1128.453000
    Metadata:
      title           : Spotify
    Chapter #0:8: start 1128.453000, end 1149.962000
    Metadata:
      title           : You trust Apple...
    Chapter #0:9: start 1149.962000, end 1333.264000
    Metadata:
      title           : What is Facebook's responsibility to their users
    Chapter #0:10: start 1333.264000, end 1498.773000
    Metadata:
      title           : Apple News
    Chapter #0:11: start 1498.773000, end 1700.850000
    Metadata:
      title           : Who's going to be Apple's competitor in the future?
    Chapter #0:12: start 1700.850000, end 1744.183000
    Metadata:
      title           : Steve Jobs parked anywhere he wants
    Chapter #0:13: start 1744.183000, end 1955.677000
    Metadata:
      title           : Jimmy Iovine told me some Steve Jobs stories
    Stream #0:0: Audio: mp3, 44100 Hz, stereo, fltp, 112 kb/s
    Metadata:
      encoder         : LAME3.99r
    Side data:
      replaygain: track gain - -6.100000, track peak - unknown, album gain - unknown, album peak - unknown, 
    Stream #0:1: Video: mjpeg (Baseline), yuvj420p(pc, bt470bg/unknown/unknown), 900x900 [SAR 1:1 DAR 1:1], 90k tbr, 90k tbn, 90k tbc
    Metadata:
      comment         : Cover (front)

This matches up well with my label track.txt file (Auphonic appears to round the numbers):

Code: Select all

6.919116	6.919116	Opener
63.220385	63.220385	Introduction: Jimmy Destri
642.801768	642.801768	I know music, and I know addiction
725.750799	725.750799	Analog synths to digital and laptops
839.764525	839.764525	Garageband
896.441869	896.441869	Today, anybody can make a record
963.603922	963.603922	iTunes really covered our asses
1057.966303	1057.966303	Spotify
1128.453512	1128.453512	You trust Apple...
1149.962145	1149.962145	What is Facebook's responsibility to their users
1333.264823	1333.264823	Apple News
1498.773451	1498.773451	Who's going to be Apple's competitor in the future?
1700.850295	1700.850295	Steve Jobs drove himself
1744.183697	1744.183697	Jimmy Iovine told me some Steve Jobs stories

I wonder if something that works like https://github.com/jcs/mp3chap could be used here to make it easier to integrate it into Audacity- the output of the labels txt file piped to it as a part of exporting the file to mp3?

Thanks for logging my vote and having read this far. I'm trying to figure out how to satisfy my listener's requests for this feature, and being able to do it all within Audacity is very desirable for me.

[ve4jhj]

Is a screen grab of mp3 chapters in VLC on Windows, taken from the Internet.

According to the Auphonic website where that image comes from, the image is showing Mp4 chapter marks, rather than MP3. MP3 Chapters are not supported in VLC on Windows based on my own testing using the files supplied by you, as well as the mp4 file supplied by Auphonic.