Stuttering every few seconds causing more latency

[Fritzwald]

Hi all!
What has been happening to me is that the video stream from the hololens on PC will stutter every few seconds, causing a 1-2 second freeze in the video (audio is fine), which then causes the stream after to be delayed by that many more seconds. So every time a stutter happens latency gets even worse.
Do you know what could be causing this?

[jamescadd]

Hello - I think you may be hitting a known issue with the H.264 decoder that causes intermittent freezes. You could try switching to VP8 to see if it resolves the issue (though CPU utilization would be higher). There is some work going on next week to attempt to resolve this, will update the issue after that.

[Fritzwald]

Hi James, yes I assumed it was due to the decoder, because I had tried the VP8 which however has a little bit of a different problem for: small consistent stutters every 2 or so seconds, which don't cause a large delay, but it results in a not smooth stream.

[devhed]

Bumping this thread. Has there been any progress on tracking down a fix for this issue?

[jamescadd]

Sadly this was postponed until the end of October due to a fire needing to be put out. I'll update the thread then (or sooner if we can address it earlier). Apologies for the delay.

[devhed]

Thanks for the prompt update @jamescadd 👍

[shaddadjr]

Hi guys, just following up to see if there are any updates on this in regards to fixing the stuttering issue. Thanks!

[jamescadd]

Checking on this now but due to some necessary people being out of office I likely won't have an answer until Monday. Will make a note to check again then and see if we can agree on a plan to resolve it with a more firm timeline. Thanks for your patience, this is something we see as necessary to resolve but has been delayed by a couple of updates to the core WebRTC UWP codebase (M66 and now M71 mergers) along with a shift in Unity from the .NET Scripting Backend to IL2CPP.

[JR06410]

Hi James, any updates on a plan to resolve HoloLens H.264 freezes? We are using VP8 currently but CPU utilization is very high. We would like to switch to H.264 and use hardware encode/decoders but this suffers from freezes. Any assistance appreciated.