1653350 - Add a profiler marker that exposes jitter in video frame timestamps

Status: RESOLVED FIXED

(Core :: Gecko Profiler, task, P3)

Description

[Markus Stange [:mstange]]

When ImageComposite::SetImages gets called, it contains the upcoming ~10 video frames. It gets called quite frequently, so most of the time, 8-10 of those frames are the same; usually one gets added at the end and one dropped from the beginning.
In a perfect world, for a given video frame (frameID,producerID), that frame's timestamp would stay fixed across multiple SetImages calls.
However, we adjust video frame timestamps based on audio playback. If we have bugs in that system (bug 1649859), or if the audio clock drifts compared to the system clock, then the timestamp for a video frame can change.
We can detect those timestamp changes and put the delta into a Gecko Profiler marker.

Comment 1

[Markus Stange [:mstange]]

Attachment: Bug 1653350 - Add a marker that shows variations in video frame timestamps. r=jrmuizel

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/63782470c325
Add a marker that shows variations in video frame timestamps. r=jrmuizel

Comment 3

[Cristina Coroiu [:ccoroiu]]

https://hg.mozilla.org/mozilla-central/rev/63782470c325