Open Bug 1601297 Opened 4 years ago Updated 2 years ago

Slight stuttering on 8K 60 fps YouTube videos on NVidia cards

Categories

(Core :: Graphics: Layers, defect, P3)

Product:
Core
Component:
Graphics: Layers
Version:
72 Branch
Type:
defect

Tracking

()

Project Flags:
Webcompat Priority P2
Tracking Flags:
Tracking Status
firefox98 --- affected
firefox99 - affected

People

(Reporter: dmitriy-muraviov, Unassigned)

References

(Blocks 1 open bug)

Details

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Firefox/68.0

Expected results:

Hardware-accelerated playback of 8K 60 fps videos on YouTube is inferior to Chrome, it exhibits slight periodic stutters. I have Nvidia GTX 1050 Ti.

Additional info:
On Chrome, all videos play perfectly smoothly, without stutters.
On Firefox, there are periodically repeating series of slight stutters on all 8K 60 fps videos on YouTube, which are not so easy to see clearly, but feeling of fluid motion noticeably suffers. There are no dropped frames indiicated in “Stats for nerds”.

My specs are:
Windows 10 1909 x64, Firefox Developer 72.0b2 x64 with new clean profile, latest drivers, Intel Core i5-760 (Lynnfield, old one), Nvidia GTX 1050 Ti (4 GB VRAM) on PCI-E 2.0 x16, 8 GB RAM, SSD, I was comparing with Chrome 78 x64.

Example 1: https://www.youtube.com/watch?v=1La4QzGeaaQ
Stuttering is especially visible on jittery movement of background trees at 1:48.

To demonstrate exactly what the issue looks like, I recorded my monitor with high-speed camera in 120 fps: https://yadi.sk/i/Nt9Z2816wOuFlA
In this video, first I test Chrome, then Firefox Developer, then try Firefox ESR (ignore ESR).

You can use MPC BE and execute menu command “Play-> Decrease Rate” or press Ctrl+Down to slow recording down to 0,5x or, even better, 0,25x speed to see stuttering more clearly.

Example 2: https://www.youtube.com/watch?v=hVvEISFw9w0
This is a better test video overall, because there are more shots with moving camera.

Because the issue is pretty difficult to see, especially on recording, I recorded playbacks of the entire video with steadily positioned camera (the right corner of the screen to see more rapid motion), first on Firefox, then on Chrome: https://yadi.sk/i/5mKWRj18daI58g

Stutters on Firefox seem to be periodic - they are not in every scene. On Chrome, there are no stutters in any scene.

Bugbug thinks this bug should belong to this component, but please revert this change in case of error.

Component: Untriaged → Audio/Video: Playback
Product: Firefox → Core

I took a look at this before it was spun off from bug 1599878 and my current suspicion is that the issue is taking place after the decoding pipeline based on that the reporter is not seeing any dropped frames in the stats for nerds.

I'm going to move this to gfx; could someone from gfx please advise how best to identify if this is taking place during composition?

Component: Audio/Video: Playback → Graphics: Layers

Dmitriy, can you attach a copy of your about:support, or at least the Graphics subsection?

Sotaro, this sounds like a video playback issue, but might be a compositing issue too. What do you think?

Flags: needinfo?(sotaro.ikeda.g)
Priority: -- → P3

My about:support - https://yadi.sk/d/_xESzDygUtt6Og

What I described above, I tested on Firefox Developer 72.

I should also note that on ESR 68.3.0 stuttering is much, much worse - it is constant through the entire video, feels like it is 20 fps with constant jitter. Here's my about:support from ESR, in case it might help https://yadi.sk/d/hV5f79PpDpZoZA . So, something that helped a lot with that issue, has been done recently, between versions 68 and 72.

(In reply to Dmitriy from comment #4)

My about:support - https://yadi.sk/d/_xESzDygUtt6Og

It used WebRender, and ESR 68.3.0 used Direct3D 11 (Advanced Layers). ESR still disable WebRender, then Direct3D 11 compositor was used instead. It mean that WebRender usage provices better FPS than Direct3D 11 compositor.

On WebRender, Bug 1460499 and Bug 1579235 are going to make better video support.

Depends on: 1460499, 1579235

OK, thank you

Flags: needinfo?(sotaro.ikeda.g)

Hello. I just wanted to add that the problem is still relevant after all these years. Theres still a slight but noticeable stuttering. Unlike many other issues this one does not seem to be fixed by itself with the new browser additions, alterations. The links above do not provide 8k 60fps option now so heres a new link
https://www.youtube.com/watch?v=YhffMf0149E.
First 10 seconds are enough to see it.
Chrome does not show this behavior, gpu is not loaded to 100% and in both browsers (chrome and firefox) the video from the link can be accelerated to 1.25 without frame skipping
Windows 10 x64 20h2, ryzen 3600, Nvidia GTX gtx 1070, 89.0 (64-bit) stable

[Tracking Requested - why for this release]: YouTube is an important website for webcompat.
see https://webcompat.com/issues/98354

status-firefox98: --- → affected
status-firefox99: --- → affected
tracking-firefox99: --- → ?
Webcompat Priority: --- → P2
See Also: → 1508017, https://webcompat.com/issues/98354

fwiw my graphic card is Intel Iris Plus Graphics 1536 Mo and I get jankiness on https://www.youtube.com/watch?v=linlz7-Pnvw

The bug has a release status flag that shows some version of Firefox is affected, thus it will be considered confirmed.

Status: UNCONFIRMED → NEW
Ever confirmed: true
Severity: normal normal → S3 S3
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