[pulseaudio-discuss] bluetooth latencies

[Alexander E. Patrakov]

I meant that these are latencies that are related to different parts
of the path.

Please send the patch, but I don't have the expertise to review it.

2017-01-30 22:46 GMT+05:00 Georg Chini <georg at chini.tk>:
> On 30.01.2017 18:37, Alexander E. Patrakov wrote:
>>
>> I am not a bluetooth expert, but: is this a different latency? Maybe
>> the situation is that the headset has its own 28-ms buffer, and
>> PulseAudio adds 25 or 125 ms on top of that?
>
>
> What do you mean by different latency? The values are passed
> to pulse via pa_{sink, source}_set_fixed_latency_within_thread()
> (plus one write block size). So pulse reports 128 ms fixed latency
> for the SCO sink, while the current latency is around 28 ms.
>
>
>>
>> 2017-01-30 21:35 GMT+05:00 Georg Chini <georg at chini.tk>:
>>>
>>> Hello,
>>>
>>> in module-bluez5-device.c and module-bluez4-device.c, latencies for
>>> bluetooth are defined as follows:
>>>
>>> #define FIXED_LATENCY_PLAYBACK_A2DP (25 * PA_USEC_PER_MSEC)
>>> #define FIXED_LATENCY_PLAYBACK_SCO (125 * PA_USEC_PER_MSEC)
>>> #define FIXED_LATENCY_RECORD_A2DP   (25 * PA_USEC_PER_MSEC)
>>> #define FIXED_LATENCY_RECORD_SCO    (25 * PA_USEC_PER_MSEC)
>>>
>>> Is the fixed latency for SCO playback a mistake? Both headsets I own
>>> report around 28 ms actual latency for the SCO sink, so I cannot
>>> understand why the fixed latency is set to 125 ms. Should I send a
>>> patch to correct it?
>>>
>>> Regards
>>>               Georg
>>>
>>> _______________________________________________
>>> pulseaudio-discuss mailing list
>>> pulseaudio-discuss at lists.freedesktop.org
>>> https://lists.freedesktop.org/mailman/listinfo/pulseaudio-discuss
>>
>>
>>
>
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-- 
Alexander E. Patrakov