mp3-chapters.md

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+Source: https://forum.audacityteam.org/viewtopic.php?f=20&t=104991&sid=0d7eadb4db3640283f6a33ac22307825&start=20
+
+First of you need to install the following as a plugin in audacity:
+
+```
+;nyquist plug-in
+;version 4
+;type tool
+;codetype lisp
+;name "Labels to Chapters"
+;author "Steve Daulton"
+;release 2.3.2
+;copyright "Released under terms of the GNU General Public License version 2"
+
+;control timebase "Time base" int "" 1000 100 2000
+;control title "Title" string "" ""
+;control encodedby "Encoded by" string "" ""
+;control artist "Artist" string "" ""
+;control date "Date" string "" "2020"
+;control filename "Save file as" file "" "*default*/metadata.txt" "Text file|*.txt;*.TXT|All files|*.*;*" "save,overwrite"
+
+
+(setf metadata
+  (format nil ";FFMETADATA1~%~
+              title=~a~%~
+              encoded_by=~a~%~
+              artist=~a~%~
+              date=~a~%~
+              encoder=Lavf58.27.103~%"
+              title
+              encodedby
+              artist
+              date))
+
+;;  Get label data from first label track
+(setf labels (second (first (aud-get-info "Labels"))))
+
+
+(dolist (label labels)
+  (setf chapter
+    (format nil "[CHAPTER]~%~
+                TIMEBASE=1/~a~%~
+                START=~a~%~
+                END=~a~%~
+                title=~a~%"
+                timebase
+                (round (* timebase (first label)))
+                (round (* timebase (second label)))
+                (third label)))
+  (string-append metadata chapter))
+
+
+(setf fp (open filename :direction :output))
+(format fp metadata)
+(close fp)
+(format nil "File written to~%~a" filename)
+```
+
+This is the code that converts your label track into an ffmpeg-metadata file.
+
+1. Save the code as a `.ny` whereever you want to keep it or where you usually save your audacity plugins.
+2. Open Audacity
+3. Go to "Tools" -> "Nyquist Plug-in Installer..."
+4. Choose the file you saved in step one and confirm
+5. Under "Tools" -> "Add / Remove Plug-ins..." make sure the new plugin was successfully added and is enabled
+6. Create your audio file with the first label track serving as chapter marks
+7. When you are done, go to "Tools" and run the newly installed plug-in, saving the `metadata.txt` somewhere
+8. Export the audio as an mp3 file
+9. Open a terminal
+10. Run `ffmpeg -i audio.mp3 -i metadata.txt -map_metadata 1 -codec copy -id3v2_version 3 -write_id3v1 1 audio-with-chapters.mp3`
+
+Don't simply copy the command, the file paths will differ ;)
+
+While this solution isn't the most straightforward, you can at least edit your chapter marks in a GUI.
+
+
+