Pi4: poor video performance (kodi, youtube)

Lebkoungcity

Howdy mates!
(To quote a colleague :lol:

)

I have a annoying problem with video performance on my Pi4. It was about one year ago I emerged almost all I needed and then didn't touch it because of a rather troublesome time... But now I managed to have it up-to-date again and began to use it as it was intended: attached to the TV via HDMI to watch stuff with kodi and sometimes fire up xfce4 to watch stuff on youtube (because the add-on for youtube within kodi requires an API-key which I refuse to accquire). Unfortunatly there are framedrops/tearing/or such when watching youtube in epiphany to a degree that makes it quite unusable, no matter which quality-setting is used (I tried to give firefox or chromium a chance but both fail to emerge...). It's almost all the same amount of framedrops/tearing. (144 and 240 don't play at all - strange!) Kodi works fine most of the time but some videos stutter (audio is fluent). I tend to say it's mostly HD - h265 or such material.
The Pi4 is a 8GB and because it should play netflix (we want video performance to be OK before we get a netflix account and pay for it) it's 32bit userland with 64bit kernel. (For some ebuilds I have to boot the 32bit kernel to emerge successfully - is this to be expected? I think so but I don't know how to get around that. But that would be another question.)

I tried some stuff I found here and in other places but without much success. Is this the best one could get? Or did I something wrong?

I'd be happy to provide any information that's needed and because I don't know where to start, here are '/boot/config.txt', '/var/lib/portage/world' and 'emerge --info'.

Thanks a lot for looking into it!
Andy

alamahant · Advocate Joined: 23 Mar 2019 Posts: 3879

Lebkoungcity · Posted: Sun Feb 20, 2022 12:23 pm Post subject:

alamahant,

I checked the points you mentioned so nicely in a list:

1. sys-apps/rng-tools was already there:

Lebkoungcity · Posted: Sat Mar 05, 2022 11:16 pm Post subject:

Hello,

it's been a while for there are far more important things than me and the RP4. But nevertheless yesterday I took a screenshot within kodi which shows that there is no hardware decoding in use. It's all the same no matter what kind of video. But those with lower resolutions than 1080p play fine - the CPU seems to be powerful enough to master this task. When playing 1080p or more it's stuttering more and more. See also the CPU load in the picture.

antonlacon · Apprentice Joined: 27 Jun 2004 Posts: 257

Gentoo Wiki's RPi VC4 article is out of date. A VC4 64-bit driver has been available for a couple of years now (RPi even has a 64-bit distro...) As an aside, I'm pretty sure the fkms device tree isn't as well maintained as the regular kms one at this point.

I'm not sure why you're expecting mesa to report VC4. RPi4 has a videocore VI gpu. This uses the mesa v3d driver to run it. VC4 is for videocore 4 (earlier RPi's).

Having said that, hardware video decoding on the RPi4 is done using V4L2-mem2mem. This is under development at the kernel and ffmpeg level. Your setup isn't wrong; the work you need just isn't upstream (and hence available in Gentoo proper).

If this is just a machine you plug into your TV, I would look at LibreElec if you have a spare sd-card laying around to try as it is one of the environments the necessary work is tested in. You can try the Tubed kodi addon for youtube, which I don't believe requires an api key setup.

If you need more general purpose, Raspberry Pi OS (formerly raspbian) should have the necessary work too. I don't know about other distros.