PA/CoreAudio reported streamInfo->input/ouputLatency may not take driver latency into account
According to the report here:
http://music.columbia.edu/pipermail/portaudio/2009-June/009205.html
Yann writes:
I'm not familiar with the details of CoreAudio but from a quick code
inspection, it looks like the CoreAudio latency calculation for
streamRepresentation.streamInfo.inputLatency / outputLatency doesn't
take into account the latency portion attributable to the driver (i.e.
at minimum I would have thought it would include the capture/playback
buffer latency). There are some comments in the code which question
the way the latency is calculated.
For more info about computing CoreAudio latency values see the comments in ticket #175 PA/CoreAudio recommended deviceInfo->default*Latency is 0
META TICKET: #181 [META] ensure reported streamInfo->input/ouputLatency values are correct
http://music.columbia.edu/pipermail/portaudio/2009-June/009205.html
Yann writes:
I'm not familiar with the details of CoreAudio but from a quick code
inspection, it looks like the CoreAudio latency calculation for
streamRepresentation.streamInfo.inputLatency / outputLatency doesn't
take into account the latency portion attributable to the driver (i.e.
at minimum I would have thought it would include the capture/playback
buffer latency). There are some comments in the code which question
the way the latency is calculated.
For more info about computing CoreAudio latency values see the comments in ticket #175 PA/CoreAudio recommended deviceInfo->default*Latency is 0
META TICKET: #181 [META] ensure reported streamInfo->input/ouputLatency values are correct
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