1891672 - Embedded figures in WEBM videos overcompressed/blurred to illegibility in Firefox 125

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, defect)

Description

[kastner.karl]

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:124.0) Gecko/20100101 Firefox/124.0

Steps to reproduce:

Played WEBM videos generated by Blue Button: https://bbb.b-tu.de/playback/presentation/2.3/9075468b3c082d2770a1fa94683c861e0b7dfe45-1713248898538

In Firefox 125.0+build1-0ubuntu0.22.04.1~mt1 on Ubuntu 22.04.3 LTS Jammy.

Actual results:

Embedded figures are not displayed correctly, but blurred due to overcompression so that the content cannot be recognized. This is the case mostly to JPEG images, but sometimes affects PNGs.

Expected results:

The video and figures should be displayed correctly with at most acceptable compression that does not render the content illegible. The figures in the WEBM videos are correctly displayed in Chrome and Firefox 124 on the same machine.

Comment 1

[Alice0775 White]

I can reproduce the issue on Nightly127.0a1 Windows11.

Regression window:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=56a1fce20849e569b75856301c801f89a0d6e0b9&tochange=3fe9e1643aafa1f8f5ba19b012b90b0d39a422b5

Comment 2

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

:aosmond, since you are the author of the regressor, bug 1711061, could you take a look? Also, could you set the severity field?

For more information, please visit BugBot documentation.

Comment 3

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

Set release status flags based on info from the regressing bug 1711061

Comment 4

[Andrew Osmond [:aosmond] (he/him)]

Are you sure about that regression window? Bug 1711061 landed in Firefox 96, while you said it works in Firefox 124?

Comment 5

[Andrew Osmond [:aosmond] (he/him)]

Oh I sorry, I see the regression window was from Alice0775 White. Would you be able to generate a different regression window given Firefox 124 works? You can use mozregression to hopefully do this easily:
https://mozilla.github.io/mozregression/quickstart.html

Comment 6

[Timothy Nikkel (:tnikkel)]

I get a regression range that agrees with Alice0775's comment 1. The issue doesn't always reproduce, I think we request the wrong size decoded image, and if we have the correctly sized image decoded we will use it, so that could explain why 124 seemed to work.

I've been working with this code for other bugs recently, I can look into this.

Comment 7

[Timothy Nikkel (:tnikkel)]

The patch in bug 1805599 fixes this for me.

I just need to create a test before landing that. This page might be useful to construct a reasonable testcase from.

Comment 8

[kastner.karl]

I reproduced this in FF 124 in Windows meanwhile. The problem occurs only sometimes, that's why it worked for me when I tested it in FF 124 at first. I also noticed that the images are properly displayed after refreshing the page. The problem might be caused by the browser sometimes displaying the thumbnails from the bottom bar instead of the image.

Comment 9

[Timothy Nikkel (:tnikkel)]

Bug 1805599 landed on nightly. Could you re-test on nightly (127)?

Comment 10

[Liz Henry (:lizzard) (relman/hg->git project)]

Tagging this for QA to verify, since the bug reporter has not responded.

Comment 11

[Paul Oiegas [:poiegas], PM for (Ecosystem QA, Services QA, WebCompat QA, Ads QA, and Solo QA teams)]

Managed to reproduce the issue on Fx125.0.1 and no longer reproduced it on Nightly 129 (2024-07-01).
I've also checked Fx 128.0b1 and Fx 127 (release) and it seems to be fixed there also. Ryan also confirmed that the fix was entered in Fx 127. I'll update the flags.