Hi,
I have this problem too since I bought a 4k monitor.
Now I finally found a way of playing 4k videos from youtube full screen on the 4k monitor with no framedrop at all !
My Hardware
- CPU : Xeon E5-1650 v4 3.6GHz (6 cores)
- 64GB RAM
- Graphic card > Radeon Pro WX 4100
- 2 Monitors : 1 x 4k +1 x FHD
My way
Not sure if everything is really needed, but this way it works for me.
- My untrusted qube is based on debian-13-xfce template
- untrusted has access to 6 cores (might not be necessary, mpv uses 300% cpu while playing) and 10GB of RAM (might also work with far less, mpv +Xorg use around 1GB RAM while playing). untrusted is allowed to fullscreen in the qubes settings
- Install freetube from https://freetubeapp.io/ (I only use it because it integrates a button to play on external player directly)
- Install smplayer :
apt install smplayer(but it looks like it uses mpv in the background) - In the freetube settings, configure external Player to smplayer
- Open smplayer, go to the settings and change the following :
- General → Video → output driver → x11
- I enabled direct rendering Not sure if it really brings something
- Performance → I checked Allow frame drop (so I can get the statistics of frame dropped with Shift + I)
- Performance → Threads for decoding : I set to 6 (numbers of cores I have)
- Network → Youtube → support for video sites = Internal Youtube support
- Options for youtube : Playback quality = 4K + use adaptive streams + use 60fps if available + allow av1 codec
For some reasons, smplayer only goes real full screen with Alt+F11 and then f
shift + I shows the stats and on my setup it works with 30 fps with no frame drop.
If I choose in the youtube options of smplayer to use mpv instead of Internal Youtube support it is laggy with frame drops. So It might be something there to check