1767185 - On Youtube, while playing a VP9 video, scrolling is stuttery (on 48/60fps videos)

Status: RESOLVED WORKSFORME

(Core :: Graphics: WebRender, defect, P2)

Description

[Mayank Bansal]

Go to https://www.youtube.com/watch?v=ySx38NqLe6E
Choose 1440p60 as the video resolution. Make sure that the video being served is VP9
forward the video a bit to make sure you are seeing the 1440p60 stream
pinch-zoom the page to make sure that the video fills the entirety of the screen
Scroll

ER: smooth scroll
AR: stuttery scroll

Profile: https://share.firefox.dev/3FbXAYs

pushes?changeset=b3c753122e8d894d2765fecc5e99c7ff49bdaec2&full=1 HTTP/1.1" 200 None
2022-05-01T15:43:15.564000: DEBUG : Found commit message:
Bug 1758601 - Enable YUV video overlay on Window on nightly r=gfx-reviewers,lsalzman

Differential Revision: https://phabricator.services.mozilla.com/D140593

2022-05-01T15:43:15.564000: DEBUG : Did not find a branch, checking all integration branches
2022-05-01T15:43:15.580000: INFO : The bisection is done.
2022-05-01T15:43:15.580000: INFO : Stopped

Comment 1

[Mayank Bansal]

Attachment: about:support

Comment 2

[Mayank Bansal]

If i set gfx.webrender.dcomp-video-overlay-win = False the bug doesnt repro.

Profile with gfx.webrender.dcomp-video-overlay-win= False : https://share.firefox.dev/3vVAYHj

Edited

Comment 3

[Mayank Bansal]

Video ID / sCPN
ySx38NqLe6E / WVME MY5A ZJDD
Viewport / Frames
1019x573*1.50 / 9 dropped of 8984
Current / Optimal Res
2560x1440@60 / 2560x1440@60
Volume / Normalized
27% / 27% (content loudness -5.3dB)
Codecs
vp09.00.51.08.01.01.01.01.00 (308) / opus (251)
Color
bt709 / bt709
Connection Speed
15477 Kbps
Network Activity
0 KB
Buffer Health
36.11 s
Mystery Text
s:4 t:152.91 b:27.111-189.023 P
Date
Sun May 01 2022 16:21:11 GMT+0530 (India Standard Time)

Comment 4

[Mayank Bansal]

Edit:
This bug repros only with VP9 videos. If I change Youtube settings to serve me AV1 video only, there is no stuttering at 1440p or even 4k video.
With VP9 video, there is stuttering even at 720p resolution.

Comment 5

[Mayank Bansal]

New finding :
The stutter doesnt repro on other videos. Example : https://www.youtube.com/watch?v=RAenE7hx2Lc&t=967s
Use 1440p resolution and VP9 video.
There is no stutter.

Video ID / sCPN
RAenE7hx2Lc / V6FD V3JH PYZF
Viewport / Frames
1019x573*1.50 / 0 dropped of 2357
Current / Optimal Res
2560x1440@24 / 2560x1440@24
Volume / Normalized
75% / 75% (content loudness -2.6dB)
Codecs
vp09.00.51.08.01.01.01.01.00 (271) / opus (251)
Color
bt709 / bt709
Connection Speed
78567 Kbps
Network Activity
0 KB
Buffer Health
49.30 s
Mystery Text
s:8 t:1221.47 b:930.001-970.387,971.637-1010.001,1190.001-1270.603
Date
Tue May 03 2022 21:39:24 GMT+0530 (India Standard Time)

Comment 6

[Mayank Bansal]

I think this may be related to 48fps or 60fps VP9 videos. Example : On https://www.youtube.com/watch?v=_q288SbISzc, i get stutters.

Comment 7

[BugBot [:suhaib / :marco/ :calixte]]

Set release status flags based on info from the regressing bug 1758601

Comment 8

[Stefano Moioli]

Hello, I am also experiencing a similar issue.
When playing back a VP9 video, the video appears to be shaking either up/down or left/right.
It seems to depend on the window size vs video size (scale factor), and it also seems to not happen when the video is not completely in view.
It definitely doesn't happen with the AV1 codec, and it is no longer reproducible on VP9 when setting the following flag, mentioned above:

gfx.webrender.dcomp-video-overlay-win = False

I took a recording of the issue, here: https://drive.google.com/uc?export=view&id=17GXUyQwggn9CDdo8HVu0kAmurd6VjOLy
I made the window smaller to maximize the effect

I'm using Firefox 100.0 (64 bit) on Windows 10 (1909) with an Intel HD630 (driver version 30.0.101.1631)
The problem started happening in Firefox 100.

Comment 9

[Sotaro Ikeda [:sotaro]]

Mayank Bansal, can you check if the problem happens with pref "gfx.webrender.dcomp-video-vp-scaling-win = false"? I wonder if the problem is related to video scaling.

Comment 10

[Sotaro Ikeda [:sotaro]]

smxdev4, can you check if the problem happens with pref "gfx.webrender.dcomp-video-vp-scaling-win = false"?

Comment 11

[Mayank Bansal]

(In reply to Sotaro Ikeda [:sotaro] from comment #9)

Mayank Bansal, can you check if the problem happens with pref "gfx.webrender.dcomp-video-vp-scaling-win = false"? I wonder if the problem is related to video scaling.

The problem still repros
https://share.firefox.dev/3vVC9b5
(Edited for more clarity)

Comment 12

[Stefano Moioli]

(In reply to Sotaro Ikeda [:sotaro] from comment #10)

smxdev4, can you check if the problem happens with pref "gfx.webrender.dcomp-video-vp-scaling-win = false"?

Thanks! I confirm that it doesn't happen with

gfx.webrender.dcomp-video-vp-scaling-win = false

(I also re-enabled "gfx.webrender.dcomp-video-overlay-win", and it keeps on working fine)

Comment 13

[Stefano Moioli]

Sorry, i was too quick. It still happens with vp-scaling-win, but it is less noticeable at higher resolutions.
I can confirm that it is related to video scaling. Here is a recording of the issue at various resolutions (vp-scaling-win=false, overlay-win=true)
https://drive.google.com/file/d/1WTYuccBBjFFQfX4c4HcUSskNoxlvvWSq/view?usp=sharing

Comment 14

[Sotaro Ikeda [:sotaro]]

Stefano Moioli, is there a reason why Windows 10 version was 1909? It seemed that support of Windows 10 (1909) was already ended.

Comment 15

[Mayank Bansal]

Attachment: about:support with overlay information

Comment 16

[Sotaro Ikeda [:sotaro]]

Mayank Bansal, can you check if the problem still happen with latest nightly? I wonder if Bug 1767212 might address the problem.

Comment 17

[Mayank Bansal]

(In reply to Sotaro Ikeda [:sotaro] from comment #16)

Mayank Bansal, can you check if the problem still happen with latest nightly? I wonder if Bug 1767212 might address the problem.

It doesnt fix the problem. The video will still stutter while scrolling on the page.
https://share.firefox.dev/3NxP60r

Comment 18

[Sotaro Ikeda [:sotaro]]

(In reply to Mayank Bansal from comment #17)

It doesnt fix the problem. The video will still stutter while scrolling on the page.
https://share.firefox.dev/3NxP60r

Wait happened at DirectComposition::CDevice::Commit(). It seemed that DirectComposition was very busy.

Comment 19

[Mayank Bansal]

Profile with latest AMD drivers and VP9 codec from Windows Store : https://share.firefox.dev/3mill8k

Comment 20

[randomreporter]

I have a similar problem on Nvidia hardware that is reproducable on both VP9 and AVC videos without need to pinch-zoom the page, scrolling fps drops on youtube/twitch when video is playing:
https://bugzilla.mozilla.org/show_bug.cgi?id=1773872
gfx.webrender.dcomp-video-overlay-win false gets rid of the issue.

Comment 21

[Pascal Chevrel:pascalc (PTO until April 26)]

Glenn, this is marked as P2/S2 but the bug is not owned and we shipped several releases with it, could we get this assigned? Thanks

Comment 22

[Glenn Watson [:gw]]

Sotaro, is this something that you're able to investigate further? Or perhaps we should drop it to S3?

Comment 23

[BugBot [:suhaib / :marco/ :calixte]]

Redirect needinfos that are pending on inactive users to the triage owner.
:gw, since the bug has high priority, high severity and recent activity, could you have a look please?

For more information, please visit auto_nag documentation.

Comment 24

[Glenn Watson [:gw]]

Sotaro, is this something that you're able to investigate further? Or perhaps we should drop it to S3?

Comment 25

[Sotaro Ikeda [:sotaro]]

(In reply to Glenn Watson [:gw] from comment #24)

Sotaro, is this something that you're able to investigate further? Or perhaps we should drop it to S3?

The problem seems to happen when video overlay is used on non-Intel GPUs. On non-Intel GPUs, video overlay is enabled only on nightly. Then Only nightly seems to be affected. From comment 18, it seems that direct composition is very busy.

Bug 1780815 is going to disable yuv video overlay. It might affect to the problem.
Bug 1773596 is going to reduce direct composition tasks. It might address the problem. But it could take a time until addressed.

If Bug 1773596 does not address it, we need to block video overlay for the GPU.

Or perhaps we should drop it to S3?

It seems better to drop it to S3.

Comment 26

[Mayank Bansal]

Bug 1780815 fixed the stuttering for me.

Comment 27

[Dianna Smith [:diannaS]]

Based on comment 26, is there any work left to do here?

Comment 28

[Sotaro Ikeda [:sotaro]]

No more work for this bug. Thank you.