[vlc-devel] [PATCH] auhal setMute (refs #7329)

[Rémi Denis-Courmont]

   Hello,

On Sunday 26 August 2012, Felix Paul Kühne wrote:
> Why does every audio output module need to save its volume (if requested by
> the user) on its own?

We have already had the same discussion on the ML for VLC 2.0 volumes. 
Practically all output back-ends with volumes save the volume internally. At 
least PulseAudio, WASAPI do, and DirectSound does it on some versions of 
Windows.

> Why isn't there a generic cross-platform implementation for this?

As already noted, there is a generic common implementation for all outputs 
with software volume.

> The bloat isn't huge, but looks like we will need
> "wasapi-volume", "auhal-volume", etc,

There is no wasapi-volume.

> while a single "volume" config would be sufficient like in 2.0.

I don't know about "sufficient", but it was buggy. The UI control was often 
unsynchronized, see Trac.

Also different outputs use different scales. ALSA would explode the eardrums if 
it used a volume saved by PulseAudio.

> For hardware volume outputs, there seems to be no way to set the volume if
> no audio output is present. This sounds logical on a technical level, but
> isn't obvious for the user.

It would be obvious if the volume control were greyed out.

> People like to change the volume prior to
> starting a clip, so this value needs to go somewhere, so it is picked up
> when the aout is created.

That would need a massive redesign of the audio output core/plugin interface, 
so that the audio output plugin runs regardless without audio track. Even then 
I am not sure it would work.

That is someone else's itch. I am not going to scratch it for the time being.

-- 
Rémi Denis-Courmont
http://www.remlab.info