On 6/7/16 2:44 AM, Alan Young wrote:
On 06/06/16 15:53, Pierre-Louis Bossart wrote:
I probably need more coffee but how is this patch helping track audio
v. wallclock drift? The additional precision is based on wallclock
deltas...
Of course, it wouldn't, due to being buggy. I think I needed more coffee
too.
But the basic point is that if the difference between tstamp and
(trigger_tstamp + audio_tstamp) varies over time, this will be the drift
between the audio output and wallclock time.
You want to track (tstamp - trigger_tstamp) v. (audio_tstamp -
trigger_tstamp)
Depending upon the specific goal, a calculation based on tstamp + delay
may be appropriate.
This is true today with a granularity of about period time. The idea
behind my change is to make the granularity much smaller, preferably < ~1ms.
I'll work on developing and testing a patch for consideration before
coming back to the last. It will be easier to discuss the merits or
otherwise of my proposal with a concrete, working patch to consider.
Alan.
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