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.
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.