If you followed the ordering example above, the 'enumeration separator' would be ' - ' (enter into the command without quotes) Supply the audiobook directory that your mp3s are in.

Save the below python script to a file then execute it.

FFMPEG ( brew install ffmpeg if you don't have it).Python3 ( brew install python if you dont have it).Order your mp3 files in a directory for just that audiobook (ex.Combine the m4a and FFMETADATA file into an m4b.Generate an FFMETADATA file ( more info) using a python script ( inspired by this) to facilitate the conversion of an m4a to m4b and preserve chapters.Note that there is still some file size bloat because the command I used to turn the caf > m4a drops the -u pgcm 2 parameter because it resulted in errors ( Couldn't set audio converter property ('prop')).Convert the combined mp3 into an m4a using afconvert (AFAIK mac-only) to reduce the amount of filesize increase from converting the mp3's to an m4a by utilizing the itunes plus commands ( stackexchange topic apple docs) (my attempts at using ffmpeg for this part resulted in huge file size bloat or long processing times).Combine the separate mp3s into a single mp3.I still use the python script to generate chapters.txt to be used with m4b-tool's merge script.Īfter a lot of research, I found a CLI solution and wanted to share my findings here (if you're looking for an app to handle this for you, I've had really good luck with Audiobook Binder, which can merge mp3s, m4as, and m4bs into a single m4b with very high efficiency). I'm going to be switching over to use their solution instead of my custom ffmpeg/afconvert. It's also possible your file is corrupt or contains unconvertible data.EDIT: Whelp, looks like m4b-tool is a great CLI tool for just this.

Encoding isįaster on desktop computers than mobile phones. This app may not work on older browsers or certain mobile phones since it uses newer browser technology. Yes! After your first download, the encoding software should cache to your browser making this an offline MP3 converter. We securely convert audio files right in your browser using codecs so you don't have to share your personal audioįiles. The MP3 file should automatically save to your device.Click the 'Convert' button to convert your file to MP3 format.After seeing the selected file appear in the file selector, you can customize your output conversion settings including bitrate, sample rate and channels.Using the file selector above, select a MP3 file from your computer or phone.

Itunes to mp3 converter multiple files