15.05.2015 10:53, Alexander E. Patrakov wrote:
15.05.2015 07:07, sylvain.bertrand@gmail.com wrote:
On Wed, May 13, 2015 at 11:32:15AM +0000, sylvain.bertrand@gmail.com wrote:
On Wed, May 13, 2015 at 11:24:32AM +0200, Clemens Ladisch wrote:
I linked the surround51 and surround71 pcms with the 'disable-able' dmix section from the default pcm.
These devices are not supposed to use plug or dmix.
Ok. Then, there is no pcm to output 5.1 sound with dmix.
Does it mean that the application is in charge to build a alsa-lib pipeline with dmix pcm and surround51 pcm, in order to let other applications output 5.1 sound at the same time?
Then what is the "Right"(tm) way to do that?
[this is my personal opinion, in no way official]
The right way seems to be to use PulseAudio. Pure ALSA, in its default configuration, just does not support mixing 5.1 audio, on any card. This default cannot really be changed, because there are many people who use 5.1 cards for output to stereo headphones only, i.e. who need automatic downmixing if an app (such as VLC) starts a 5.1 stream. The default plug/dmix setup provides such downmixing.
I need to test things before posting. This is wrong, plug/dmix does not include the extra channels in the stereo mix.
As an application developer, just tell your users "your default device needs to support 5.1, see you there", as mpv developers did. This will be the case either with PulseAudio or with a hacked .asoundrc.
This is still my position.