Commit Graph

3 Commits

Author SHA1 Message Date
wm4 ecc6e379b2 audio/out: channel map selection
Make all AOs use what has been introduced in the previous commit.

Note that even AOs which can handle all possible layouts (like ao_null)
use the new functions. This might be important if in the future
ao_select_champ() possibly honors global user options about downmixing
and so on.
2013-05-12 21:24:57 +02:00
wm4 ab8f28a672 audio: add channel map selection function
The point is selecting a minimal fallback. The AOs will call this
through the AO API, so it will be possible to add options affecting
the general channel layout selection.

It provides the following mechanism to AOs:
- forcing the correct channel order
- downmixing to stereo if no layout is available
- allow 5.1 <-> 5.1(side) fallback
- handling "unknown" channel layouts

This is quite weak and lots of code/complexity for little gain. All AOs
already made sure the channel order was correct, and the fallback is of
little value, and could perhaps be done in the frontend instead, like
stereo downmixing with --channels=2 is handled. But I'm not really sure
how this stuff should _really_ work, and the new code will hopefully
provides enough flexibility to make radical changes to channel layout
negotiation easier.
2013-05-12 21:24:57 +02:00
wm4 0042735d7a audio: add channel map API
Unused, will be used in the following commits.

Let chmap.h define the number of maximum channels, because that is most
convenient.
2013-05-12 21:24:54 +02:00