MPV not preventing blank screen while watching a video

[zakora]

mpv version and platform

> mpv --version
mpv 0.28.0 (C) 2000-2017 mpv/MPlayer/mplayer2 projects
 built on UNKNOWN
ffmpeg library versions:
   libavutil       56.7.100
   libavcodec      58.9.100
   libavformat     58.3.100
   libswscale      5.0.101
   libavfilter     7.11.101
   libswresample   3.0.101
ffmpeg version: git-2018-01-15-93028f4

OS: Fedora 27
Gnome 3.26.2 on Wayland

Reproduction steps

1. In Gnome, configure blank screen to 1 min.
2. mpv --no-config TalkativeCat2012.mp4 or mpv --fullscreen --no-config TalkativeCat2012.mp4

Expected behavior

Video playing without getting a blank screen after 1 min.

Actual behavior

After 1 min, the blank screen appears.

Log file

https://gist.github.com/zakora/4474d0e31996a9befda59336d8774750#file-mpv-log

Sample files

https://ia800609.us.archive.org/26/items/TheTalkativeCat/TalkativeCat2012.mp4

[zakora]

After some testing I found that if I run mpv under a "Gnome on X.org" session then the blank screen doesn't appear during video playback, which solves the problem.

I also tested the --stop-screensaver option under a Wayland session but it doesn't work.

[zakora]

Maybe a duplicate of #5015 .

Also, running mpv with gnome-session-inhibit solves the problem, although I find it a bit hacky and would prefer that mpv does inhibit idle by itself:

gnome-session-inhibit mpv TalkativeCat2012.mp4

[orbea]

If I understand correctly mpv uses xdg-screensaverand if gnome 3 does not respect that the possible reasons are: A gnome bug, missing dependencies (I have seen missing xprop result with similar issues in other programs) and/or a misconfiguration. Is it possible to bring this up with gnome devs and so that it can be ensured that gnome3 is properly respecting xdg-screensaver?

[glaubersm]

is your mpv running under wayland or xwayland?
https://bugzilla.gnome.org/show_bug.cgi?id=709500

[zakora]

@orbea Sure, I'll try to find a way to check that Gnome 3 respects xdg-screensaver. All I can tell for now is that running xdg-screensaver lock in my normal session (Gnome 3 on Wayland) actually locks the screen.

@glaubersm my mpv is running under Wayland. I will follow the Gnome bug thread you mentioned. It is not exactly the same issue that I have though, since the screen blanking during playback is only happening with mpv (Firefox and VLC are fine).

[zakora]

After some testing I can say that Gnome 3 seems to respect xdg-screensaver. Running xdg-screensaver suspend WINDOW_ID (with WINDOW_ID being the mpv window ID given by xwininfo) actually works: the screen blanking is inhibited during video playback for mpv.

Note for Fedora users: xdg-utils, which provides xdg-screensaver, appears to be missing some dependencies and the previous suspend command might not work out of the box. In this case you need to install perl-Net-DBus and perl-X11-Protocol, see https://bugzilla.redhat.com/show_bug.cgi?id=1541980.

Digging deeper into mpv, I found that it doesn't use the wayland code though my Gnome session runs on Wayland.
In fact, looking at the verbose mpv logs when playing a video shows two lines related to screensaver

[ 0.114][v][vo/gpu/x11] Disabling screensaver.

and

[ 2.616][v][vo/gpu/x11] Enabling screensaver.

See https://gist.github.com/zakora/8f004063d2d32b39bdcd706fdc4481fe#file-mpv-log-L747 (lines 747 and 762).

I would have expected to see the logging strings Enabling idle inhibitor and Disabling the idle inhibitor, from the wayland_common.c file.
Instead it prints the Disabling screensaver and Enabling screensaver logging strings from x11_common.c.

The git history shows that there was a lot of work done on Wayland recently by @atomnuker . Maybe he could give us some insights?

[CounterPillow]

Can you try with --gpu-backend=wayland?

[zakora]

This option is not available in mpv 0.28.0:

> mpv --gpu-backend=wayland --no-config -v TalkativeCat2012.mp4 
[cplayer] Command line options: '--gpu-backend=wayland' '--no-config' '-v' 'TalkativeCat2012.mp4'
[cplayer] mpv 0.28.0 (C) 2000-2017 mpv/MPlayer/mplayer2 projects
[cplayer]  built on UNKNOWN
[cplayer] ffmpeg library versions:
[cplayer]    libavutil       56.7.100
[cplayer]    libavcodec      58.9.100
[cplayer]    libavformat     58.3.100
[cplayer]    libswscale      5.0.101
[cplayer]    libavfilter     7.11.101
[cplayer]    libswresample   3.0.101
[cplayer] ffmpeg version: git-2018-01-15-93028f4
[cplayer] 
[cplayer] Configuration: ./waf configure --prefix=/usr --bindir=/usr/bin --libdir=/usr/lib64 --mandir=/usr/share/man --docdir=/usr/share/doc/mpv --confdir=/etc/mpv --disable-build-date --enable-libmpv-shared --enable-sdl2 --enable-dvdread --enable-dvdnav --enable-cdda --enable-dvb --enable-libarchive --enable-zsh-comp --disable-lgpl --enable-encoding
[cplayer] List of enabled features: 51fbsd alsa asm atomics cdda cplayer cplugins cuda-hwaccel debug-build drm dvbin dvdnav dvdread dvdread-common egl-drm egl-helpers egl-x11 encoding fchmod ffmpeg gbm gbm.h gl gl-x11 glibc-thread-name glob glob-posix gnuc gpl iconv jack jpeg lcms2 libaf libarchive libass libass-osd libav-any libavcodec libavdevice libbluray libdl libm libmpv-shared librt linux-fstatfs lua optimize oss-audio plain-gl posix posix-or-mingw posix-spawn posix-spawn-native pthreads pulse rubberband sdl2 stdatomic uchardet vaapi vaapi-drm vaapi-egl vaapi-glx vaapi-x-egl vaapi-x11 vdpau vdpau-gl-x11 vt.h x11 xv zlib zsh-comp
[cplayer] Error parsing option gpu-backend (option not found)
[cplayer] Setting commandline option --gpu-backend=wayland failed.
[cplayer] 
[cplayer] Exiting... (Fatal error)

Also, wayland is not listed as a GPU context:

> mpv --gpu-context=help
GPU contexts (APIs):
    auto (autodetect)
    x11probe (opengl)
    x11egl (opengl)
    x11 (opengl)
    drm (opengl)
    vdpauglx (opengl)

[mia-0]

Your mpv is built without Wayland support.

[glaubersm]

I just tested mpv 0.27 in Gnome 3.26.2, Wayland session, Arch Linux
mpv -opengl-backend=wayland video.mp4
A borderless mpv window plays the video and my screen turns off during playback.
This problem also happens under KDE Plasma Wayland session. It's very annoying and there is no precise explanation or solution so far.

[mia-0]

0.27.0 is too old and lacks many bugfixes for Wayland support. Also, the lack of window decorations is a Wayland protocol/compositor issue, not our problem. We won’t implement client-side decorations in the foreseeable future.

[glaubersm]

installed 0.28 from AUR some minutes ago.
Same problem.

[zakora]

@lachs0r Indeed, my mpv was not build with Wayland support. I'll try to build it manually or ask the package maintainer to enable wayland support.

@glaubersm Could you check mpv -v with mpv 0.28.0 and check that wayland is in "[cplayer] List of enabled features"?
If you used the mpv-full PKGBUILD, then mpv should be compiled with Wayland support according to https://aur.archlinux.org/cgit/aur.git/tree/PKGBUILD?h=mpv-full#n100

[glaubersm]

I installed mpv-full. Wayland support is enabled.

[CounterPillow]

installed 0.28 from AUR some minutes ago.
Same problem.

Probably using a GTK/Gnome version without the server side decoration protocol then. I'm fairly sure atomnuker implemented it.

[mc4man]

As far as gnome that bug report does seem relevant. Doesn't matter if mpv builds with support for the protocol as the current compositor doesn't support it. Ex.
$ strings /usr/bin/mpv |grep inhibit
Enabling idle inhibitor
Disabling the idle inhibitor
zwp_idle_inhibit_manager_v1
zwp_idle_inhibitor_v1
create_inhibitor

0.024][v][vo/gpu/opengl] Initializing GPU context 'wayland'
[ 0.024][v][vo/gpu] Enabling event driven renderloop!
[ 0.024][v][vo/gpu/wayland] Registered for protocol wl_compositor
[ 0.024][v][vo/gpu/wayland] Registered for protocol wl_shm
[ 0.024][v][vo/gpu/wayland] Registered for protocol wl_output
[ 0.024][v][vo/gpu/wayland] Registered for protocol wl_data_device_manager
[ 0.024][v][vo/gpu/wayland] Registered for protocol zxdg_shell_v6
[ 0.024][v][vo/gpu/wayland] Registered for protocol wl_seat
[ 0.024][v][vo/gpu/wayland] Compositor doesn't support the org_kde_kwin_server_decoration_manager protocol!
[ 0.024][v][vo/gpu/wayland] Compositor doesn't support the zwp_idle_inhibit_manager_v1 protocol!

[CounterPillow]

So to summarise:

1. make sure you're using the wayland gpu backend (and have actually built with wayland support)
2. make sure your compositor is up-to-date enough to support both of these protocols
3. make sure your mpv version is up-to-date enough to support both of these protocols (i.e. 0.28 or newer)
4. if all of these 3 points are fulfilled, post a log generated with --log-file.

If points 1 through 3 are not applicable, it's not upstream mpv's issue.

[glaubersm]

Both Gnome and mpv 0.28 use Wayland backend on my system.
My compositor (mutter) is updated.
My mpv is updated (0.28)

Monitor turns off during video playback anyway.

[CounterPillow]

Where's the full debug log then, @glaubersm ?

[glaubersm]

See attachment. Thanks.
mpvlog.txt

[CounterPillow]

[   0.385][v][vo/gpu/wayland] Compositor doesn't support the org_kde_kwin_server_decoration_manager protocol!
[   0.385][v][vo/gpu/wayland] Compositor doesn't support the zwp_idle_inhibit_manager_v1 protocol!

Well there's your problem.

[glaubersm]

Which Wayland compositor currently supports any of these protocols?

[CounterPillow]

KWin supports both of them. Sway supports the decorations protocol. GNOME should be supporting the decorations protocol too in an upcoming release of Gtk, if I remember correctly.

[glaubersm]

Thanks. I will test mpv 0.28 under KDE Plasma 5.12 Wayland later.

[glaubersm]

Just tested... mpv 0.28 keeps my monitor active under KDE Plasma Wayland.

[zakora]

To sum up, in order to circumvent the screen blanking under a Wayland session:

• users need at least mpv 0.28, since there was a lot of work done for Wayland since 0.27
• users need an mpv version compiled with Wayland support (not the case currently for Fedora 27)
• users need a compositor that respects the zwp_idle_inhibit_manager_v1 protocol (so if I understand correctly, mpv will not use xdg-screensaver under Wayland)

If this is correct we should close the issue, as mpv is not at fault.

[glaubersm]

I can be wrong, but I think Gnome currently does not support screensavers.

[emersion]

Sway supports the decorations protocol.

The idle-inhibit protocol is being implemented.

GNOME should be supporting the decorations protocol too in an upcoming release of Gtk, if I remember correctly.

GTK supports it, but GNOME (aka Mutter) doesn't. It means mpv won't be able to use the decorations protocol in a GNOME session.

[zakora]

Closing for now, as the original screen blanking issue is solved by having the latest mpv and capable environment.
I will reopen if I have the issue when I can test mpv 0.28 with Wayland support under Gnome Wayland.

[mc4man]

On 02/07/2018 08:27 AM, zakora wrote: Closing for now, as the original screen blanking issue is solved by having the latest mpv and capable environment. I will reopen if I have the issue when I can test mpv 0.28 with Wayland support under Gnome Wayland. — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#5459 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AFr3We8LWmgQPG5_nYUF5DuLyKbEq4xrks5tSaTLgaJpZM4RwWVW>.

wayland support for mpv 0.28+ in gnome won't solve your issue, I believe you'll also need support for the inhibit protocol in mutter. If that's so you may check here on occasion. https://gitlab.gnome.org/GNOME/mutter/issues/20

[zakora]

Thanks for the valuable info @mc4man , I'll keep on eye on the Gnome issue.

[MrMagne]

I know this issue is closed, but on gnome it works to set up an inhibitor. It works with the dbus API of 'org.gnome.SessionManager'. I made a small example in python for inhibiting when mpd is playing, code is very simple: https://github.com/MrMagne/mpdIdleInhibitor/blob/master/mpdIdleInhibitor.py

[All3xJ]

Bug still present. To fix: https://wiki.archlinux.org/title/Mpv#GNOME_Blank_screen_(Wayland)

[RevAngel7]

Same issue under ubuntu 22.04 (20.04 was fine), wayland, mpv 2.0.33-focal1

[HubKing]

Bug still present.

Well, I had the same problem in almost 2023, and that is why I came here in the first place. But it may not be a "bug". Installing this solved the problem, and its author says:

This is needed because neither mpv supports GNOME's inhibition protocol, nor GNOME supports the standard inhibition protocol (yet).

I do not know well about Linux, but if Gnome's way is not "the standard", then maybe it is Gnome's fault that it does not follow the standard.