Convert M4B Audiobook to MP3

Convert an .m4b audiobook to .mp3 while keeping its metadata and dropping the embedded cover-art video stream.

Quick reference

ffmpeg -i input.m4b -map_metadata 0 -vn -c:a libmp3lame -qscale:a 2 output.mp3

Flags

• -i input.m4b - the source file
• -map_metadata 0 - copy metadata (title, author, chapters tags) from the first input
• -vn - drop the video stream, which on an .m4b is the embedded cover art
• -c:a libmp3lame - encode audio with the LAME MP3 encoder
• -qscale:a 2 - variable bitrate quality, roughly 190 kbps (lower number is higher quality)