Bug 774513 – www-client/firefox-86.0 fails to play video when 'system-av1' use flag is enabled

• Product: Gentoo Linux
• Status: RESOLVED OBSOLETE

[Description Egor 2021-03-06 18:58:49 UTC]

After updating to Firefox 86 - it fails to play any video.

dmesg output has a lot of following messages:
[92413.623157] MediaPD~oder #2[16222]: segfault at 7f24e05ac5d0 ip 00007f24efb419cd sp 00007f24e05ac5d0 error 6 in libxul.so[7f24ed0aa000+4e1a000]
[92413.623164] Code: 00 00 00 4c 01 b5 68 ff ff ff 4c 01 b5 60 ff ff ff 48 63 c1 48 89 e7 48 01 c0 48 83 c0 0f 48 83 e0 f0 48 29 c7 48 39 e7 7c 14 <48> c7 04 24 00 00 00 00 48 81 ec 00 10 00 00 48 39 e7 7d ec 48 89
[92413.700085] MediaPD~oder #2[16236]: segfault at 7fa29206b5d0 ip 00007fa2a15f09cd sp 00007fa29206b5d0 error 6 in libxul.so[7fa29eb59000+4e1a000]
[92413.700091] Code: 00 00 00 4c 01 b5 68 ff ff ff 4c 01 b5 60 ff ff ff 48 63 c1 48 89 e7 48 01 c0 48 83 c0 0f 48 83 e0 f0 48 29 c7 48 39 e7 7c 14 <48> c7 04 24 00 00 00 00 48 81 ec 00 10 00 00 48 39 e7 7d ec 48 89

Running firefox with gbd produces following message:
[Child 31220, MediaDecoderStateMachine #1] WARNING: Decoder=7fffb2430400 Decode error: NS_ERROR_DOM_MEDIA_FATAL_ERR (0x806e0005) - auto mozilla::MediaChangeMonitor::CreateDecoderAndInit(mozilla::MediaRawData *)::(anonymous class)::operator()()::(anonymous class)::operator()(const mozilla::MediaResult &) const: Unable to initialize decoder: file /var/tmp/portage/www-client/firefox-86.0/work/firefox-86.0/dom/media/MediaDecoderStateMachine.cpp:3474

Firefox use flags:
Installed versions:  86.0(0/86)(22:54:02 04.03.2021)(clang dbus gmp-autoupdate hwaccel openh264 pulseaudio screencast system-av1 system-harfbuzz system-icu system-jpeg system-libevent system-libvpx system-webp wayland wifi -debug -eme-free -geckodriver -hardened -jack -lto -pgo -selinux CPU_FLAGS_ARM="-neon" L10N="de ru -ach -af -an -ar -ast -az -be -bg -bn -br -bs -ca -ca-valencia -cak -cs -cy -da -dsb -el -en-CA -en-GB -eo -es-AR -es-CL -es-ES -es-MX -et -eu -fa -ff -fi -fr -fy -ga -gd -gl -gn -gu -he -hi -hr -hsb -hu -hy -ia -id -is -it -ja -ka -kab -kk -km -kn -ko -lij -lt -lv -mk -mr -ms -my -nb -ne -nl -nn -oc -pa -pl -pt-BR -pt-PT -rm -ro -si -sk -sl -son -sq -sr -sv -ta -te -th -tl -tr -trs -uk -ur -uz -vi -xh -zh-CN -zh-TW") 

Fixed video playback issue after disabling 'system-av1' use flag.

My system has:
- dav1d 0.8.0 version
- libaom 2.0.0 version

Originally posted on Gentoo forum here: https://forums.gentoo.org/viewtopic.php?p=8583390#8583390

[Comment 1 Geoff Leach 2021-03-15 02:04:03 UTC]

I'm using firefox with system-av1. Works for me. However, I did find at one  point a few revs ago a problem with no audio. Now on firefox-86.1, dav1d-0.8.2, libaom-2.0.1

Sorry, probably doesnt help reporter much.

[Comment 2 Geoff Leach 2021-03-15 02:16:30 UTC]

Sorry, correction. Seems firefox is playing VP9 not AV1 - as reported by 'stats for nerds'

[Comment 3 Geoff Leach 2021-03-15 03:02:07 UTC]

Ok, looked in to it some more.

My firefox can play AV1. I downloaded

https://tools.woolyss.com/html5-audio-video-tester/?u=https://woolyss.com/f/caminandes-1-llama-drama-av1-opus.webm&m=video/webm;%20codecs=%22av01.0.04M.08.0.110,opus%22

and saved locally then played with firefox worked fine. VLC also (no audio though).

But I cant get youtube to present any AV1, only VP9, even after changing AV1 setting to 'always prefer AV1'. Does YT have AV1 examples on it?

[Comment 4 Egor 2021-04-18 11:56:28 UTC]

With Firefox 87.0-r1 everything is working again when system-av1 use flag is enabled.