[MPlayer-users] Getting audio out of mplayer on Android

[Reimar Döffinger]

On Sun, Oct 26, 2014 at 08:55:43PM -0400, Stefan Monnier wrote:
> I'm trying to get mplayer to play DVDs on my Android "TV stick".
> 
> I have mplayer's video output working (outputting to fbdev), but can't
> get a sound.  The problem seems to be that when mplayer tries to open
> the audio device (using ALSA) it gets told that the device is busy
> because it's already used by the Android "mediaserver" process.

Some people seem to have managed to compile ALSA with dmix support
on Android. That would fix that, but that is not a really good solution
for a few reasons.

> So to get sounds, I need mplayer to send its audio samples to Android's
> mediaserver (which apparently uses an API called AudioFlinger).

The AudioFlinger API to my knowledge is only supported "Java" side.
>From C code, the supported one is OpenSL.

> Is there a corresponding "audio output" plugin for it?
> If not, does anyone know of some potentially round-about way to get it
> working (e.g. using some network audio protocol)?

Supposedly the openal-soft (or so) library exists and will translate
OpenAL calls to OpenSL. MPlayer has an OpenAL backend.
The better solution would be to write an OpenSL audio output module.
Which shouldn't be hard, except that the only implementation(s) of
OpenSL seem to exist in Android, which makes implementing and
testing a huge pain.