Convert M4B to MP2

Turn M4B recordings into MP2. Re-encoded as MPEG-1 Audio Layer II at 192 kbit/s or the allowed rate nearest audio.bitrate and at 32, 44.1 or 48 kHz in mono or stereo, unless audio.sample_rate or audio.channels say otherwise, which loses a little more than the AAC already did.

Converted in an isolated sandbox on our serversDeleted after 24 hours

Drop M4B files on the dialor turn it to pick what to do

M4B and MP2

From

M4B Audiobook

AAC audiobooks in an MP4 container with chapters. What Apple Books and most audiobook apps play.

Extensions: .m4b
MIME type: audio/mp4
Kind: Audio

To

MP2 Audio

MPEG audio layer II, the sound of DVDs, DAB radio and broadcast.

Extensions: .mp2
MIME type: audio/mpeg
Kind: Audio

Options for M4B to MP2

audio.bitrate: Audio bitrate in kbit/s.
audio.channels: Number of audio channels. 1 is mono, 2 is stereo.
audio.denoise: Reduce steady background noise.
audio.normalize: Normalize loudness to -16 LUFS as streaming services do.
audio.sample_rate: Audio sample rate in Hz.
speed: Playback speed multiplier. 2 plays twice as fast.
trim_end: Second at which the audio or video stops.
trim_start: Seconds to cut from the start of audio or video.