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Issue 604051 link

Starred by 2 users

Issue metadata

Status: WontFix
Owner:
Closed: May 2016
Components:
EstimatedDays: ----
NextAction: ----
OS: ----
Pri: 3
Type: Bug



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A/V sync lost while playing 4K 60FPS vp9 videos in Desktop mode of Chrome browser.

Reported by matth...@nvidia.com, Apr 15 2016

Issue description

Chrome Version       : 49
URLs                 : https://www.youtube.com/watch?v=aqz-KE-bpKQ
OS version           : Marshmallow
Network              : wifi
Audio/Video format   : vp9 4k 60hz video


This is a video issue using Chrome app on Android (mainly tablet and phones such as Pixel C, Samsung s7 and Nexus 6p) using Desktop mode playing a 4k 60hz video. The video plays back on most devices but the video slows down behind the audio and is not synchronized. Chrome version does not seem to affect playback.


What steps will reproduce the problem?
(1) Open chrome and go to url https://www.youtube.com/watch?v=aqz-KE-bpKQ 
(2) Go to settings and turn on desktop mode
(3) Change the quality of the video to 4k60fps
(4) Seek to 6:30 and watch about 2 minutes of the video with audio

What is the expected result?
Expected to play normally, no A/V sync lost.

What is the actual result?
Immediately or soon the audio is desynced with video and video lags behind audio.


 
Owner: dalecur...@chromium.org
Status: Assigned (was: Unconfirmed)
Fix in progress already here: https://codereview.chromium.org/1863373002
Status: Fixed (was: Assigned)
Should be fixed on M52, are you able to retest?

Comment 3 by matth...@nvidia.com, May 10 2016

Would this be chrome dev on the playstore? I tested this 2 weeks ago (chrome dev) and the video was a lot slower and almost unplayable.
Status: WontFix (was: Fixed)
Oh, nevermind, I just realized this is 4k60 vp9, there's no way these devices can play that quality. Even if I open a raw 4k60 vp9 stream in VLC it can't play. Now instead of av sync drifting forever we'll pause instantly.
Just checked on an S6 w/ hardware vp9 and it can't keep up either. I don't think current gen mobile/tablet devices are capable of playing this smoothly yet.
did find https://codereview.chromium.org/1963413002/ which should resolve slowness on more recent builds where the software decoder was getting invoked instead of the hardware one.

My s6 is not capable of 4k60, but maybe pixel c + s7 are.
 issue 610892  raised the hw decode limits, so we'll at least try the hardware decoder now if it's available on the device.

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