I want to encode some multichannel 5.1 FLAC files to m4a with QAAC.
I don't know the commands.
Right now I'm using this:
--ignorelength -s --no-optimize -V 127 -o %d -
I'm pretty sure this commands are for STEREO encoding.
What should I add to this command ?
The VBR setting you appear to be using would be quality based, which scales depending on the channel count.
I'm pretty sure this commands are for STEREO encoding.
Have you given it a try as-is and seen what the output looks like? https://github.com/nu774/qaac/wiki/Multichannel--handling (https://github.com/nu774/qaac/wiki/Multichannel--handling) . Also from qaac command line options:
--chanmap Rearrange input channels to the specified order.
Example:
--chanmap 2,1 -> swap L and R.
--chanmap 2,3,1 -> C+L+R -> L+R+C.
--chanmask Force input channel mask(bitmap).
Either decimal or hex number with 0x prefix
can be used.
When 0 is given, qaac works as if no channel mask is
present in the source and picks default layout.
And as kode54 indicated: "True Variable Bitrate gives you a specific quality. The bitrate is free to vary as much as necessary, and generally the more channels, the higher the bitrate, as you're specifying a quality regardless of the channel count. All the other encoding modes let you control the bitrate in some way, but the selected bitrate is not directly related to quality." (https://forum.videohelp.com/threads/378450-Best-settings-for-QAAC#post2444452 (https://forum.videohelp.com/threads/378450-Best-settings-for-QAAC#post2444452))
Chanmask should be handled automatically under foobar2000 anyway, as foobar emits WAVEFORMATEXTENSIBLE with a channel mask field.