On Fri, 2017-09-29 at 11:46 +0200, Ludovic Guégan wrote: > Hi everyone, > > First, i am new to PulseAudio and the mailing list, so let me say it: Thank > you all ! > > In the context of my application, it is important to accurately estimate > the audio latency in order to synchronize the speaker output with some > motor movements. > > I used to query the audio latency using pa_stream_get_latency(), but the > returned information does not seems to correspond to observed latency in > the following situation: > > When my application stops sending data (after the underflow event), the > value returned by pa_stream_get_latency() stays constant and does not > decrease. > > When writing again data into the stream (long after the underflow event and > without any cork/uncork operation), the sound is outputted to the speaker > without the latency delay advertised by pa_stream_get_latency(). > > Since this is the first time i use the PulseAudio API, i might not > understand correctly the purpose of pa_stream_get_latency() and I wonder > what is the correct way to obtain the most accurate estimation of the > latency ? During an underrun you can't get exact latency information. When you resume playing audio, a part of the device buffer may or may not get rewritten, and it's not known in advance how much will be rewritten. I recommend playing silence instead of playing nothing in your application. -- Tanu https://www.patreon.com/tanuk
