[pulseaudio-discuss] module-role-cork and mp3s

[Georg Chini]

On 14.08.2015 09:33, Mikhail Morfikov wrote:
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> On 2015-08-14 01:14, Georg Chini wrote:
>> On 13.08.2015 23:29, Mikhail Morfikov wrote:
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>>> On 2015-08-13 18:49, Georg Chini wrote:
>>>> On 13.08.2015 14:58, Tanu Kaskinen wrote:
>>>>> On Thu, 2015-08-13 at 10:50 +0200, Mikhail Morfikov wrote:
>>>>>> I have two streams one phone and one video/audio, and when I set the
>>>>>> following:
>>>>>>
>>>>>> load-module module-role-ducking trigger_roles=phone
>>>>>> ducking_roles=music,video volume=60%
>>>>>>
>>>>>> and I start playing an mp3, the volume is lowered to 60% and that's
>>>>>> fine. Each time a new mp3 is being played the volume doesn't change,
>>>>>> which is also a good thing.
>>>>>>
>>>>>> There's another module module-role-cork and when it's enabled (also
>>>>>> commenting out the line above), it acts a little bit strange. When I
>>>>>> start the phone stream, the mp3 is muted, and that's expected, but
>>>>>> when
>>>>>> another mp3 starts to play, the sound appears.
>>>>>>
>>>>>> Should that happen?
>>>>> Ideally that shouldn't happen, but currently we have a bit limited
>>>>> support for managing corking. Currently applications are required to
>>>>> cooperate when we want to cork them. module-role-cork sends a cork
>>>>> request to an application, and the application will then obey that
>>>>> request (or not, but in your case not obeying the request is not the
>>>>> problem). To make this work on new streams too, module-role-cork should
>>>>> send the cork request also when a new stream appears, which it
>>>>> currently doesn't do. It could very well do that, so patches welcome!
>>>>>
>>>>> Sending a cork request after a new stream has appeared isn't quite
>>>>> optimal, since the beginning of the stream may already hit the speakers
>>>>> before the corking happens, but that would still be better than the
>>>>> current behaviour.
>>>>>
>>>>> It would be good to have "server-side corking" that wouldn't require
>>>>> cooperation from applications. That's a bit more complicated to
>>>>> implement.
>>>>>
>>>> Hi,
>>>>
>>>> you could try if my patches
>>>> http://thread.gmane.org/gmane.comp.audio.pulseaudio.general/23189
>>>> solve the problem because the patches combine module-role-cork
>>>> and module-role-ducking (and I believe they should mute/cork a stream
>>>> when it appears).
>>>>
>>>> Regards
>>>>               Georg
>>>> _______________________________________________
>>>> pulseaudio-discuss mailing list
>>>> pulseaudio-discuss at lists.freedesktop.org
>>>> http://lists.freedesktop.org/mailman/listinfo/pulseaudio-discuss
>>> I've tested the patches, but nothing has changed.
>>>
>> That's strange because with the patches both modules share the
>> same code. So I would have expected that they behave equally.
>> Can you check if there is any difference between the two cases by
>> running pulseaudio with debugging? There should be a line in the
>> log each time the module interacts with a stream.
>>
>> Georg
>>
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> I've compared the debug logs in both cases (with and without patches)
> and checked whether they're different in any point. There are 3
> occurrences of stream-interaction.c in the log with patches:
>
> D: [pulseaudio] stream-interaction.c: Using role 'phone' as trigger role.
> D: [pulseaudio] stream-interaction.c: Using roles 'music' and 'video' as cork roles.
> ...
> D: [pulseaudio] stream-interaction.c: Found a 'phone' stream that corks/mutes a 'video' stream.
>
> And there's also:
>
> D: [pulseaudio] sink-input.c: The mute of sink input 0 changed from no to yes.
>
> And that's it. I can provide you with the full logs if you needed them.
>

I was rather thinking about a comparison between module-role-cork
and module-role-ducking with the patches because they behave differently
even though the code is exactly the same. I would expect, that when you
compare the log messages there should be no difference except that it
says "cork" for one module and "duck" for the other.

One reason I can think of why there is a problem with role-cork but not with
role-ducking is that the new stream might still be corked when the 
sink_input
is put. So role-cork sees the stream as corked and does nothing but the
application uncorks the stream at a later time.

Regards
              Georg