How to convert raw multi-channel audio (MLP/TrueHD) to multi-channel compressed FLAC ?

[laniciffo]

Hello,

I would like to compress some multi-channel audio files using the lossless FLAC codec, but I just can't find the right options to do so.
First : is it feasible ?
Next : is it feasible with VLC ?
Next : is there a significant file size reduction ?

The input files are HUGE : 450 MB for a 10 minutes track (no video included !), so I really want to compress them as much as possible.

Could someone kindly guide me to achieve this rather rare conversion ?

OS : Win 11
VLC version : 3.0.16 Vetinari

Source file :
Extension : .mlp
Codec : MLP/TrueHD Audio (mlp)
Type : Audio
Channels : 3F2R/LFE
Sampling F : 96000 Hz
Bits per sample : 32 (but the original recording reported only 24)

Desired output file :
Extension : .flac
Codec : compressed multi-channel FLAC (don't know VLC's exact name for this format)
Type : Audio
Channels : 3F2R/LFE
Sampling F : 96000 Hz
Bits per sample : 24 (or 32 ?)

Changing the container type to FLAC while keeping the audio track unchanged works fine. VLC can play the new file without a problem.
But I do not know what options I should select to store in the FLAC container COMPRESSED multi-channel audio.

Can anyone help ?

Many thanks to all developers and contributors !

Diego Coste from France