Transcoding seems to be an issue on my Raspberry Pi 400

[changemewtf]

Hi there Jellyfins. I finally snagged a RPi400 from Adafruit, where they specifically advertise it as having " 4kp60 HEVC decode ". On the Raspberry Pi site itself, it just says "4k video playback".

However, I am getting some serious stuttering and quality issues across various videos. My clients are an LG TV with the Jellyfin app, a Samsung Galaxy Note 20 Ultra using the integrated player, and the web player in Firefox on Windows 10. They all share the same behavior: On certain videos there will be very degraded quality. On others, the video will play for 3 - 5 seconds, freeze for 3 - 5 seconds, then repeat.

I used mediainfo to interrogate some of the problem files. The most egregious is a 8GB copy of Nausicaa of the Valley of the Wind, filename "Nausicaa of the Valley of the Wind (1984) [1080p x265 HEVC 10bit BluRay Dual Audio AAC] [Prof]". When I try to play, it does the play/freeze/play/freeze/etc. thing. I observed the system performance through htop and all four cores hover at 80 - 100% when trying to play these problematic videos.

Hardware acceleration is enabled on the Jellyfin Pi. I started following this guide from 4 years ago, but stopped when I realized that OpenMAX is no longer supported on the Pi. So I went to the official docs. I do see all the warnings on that page, so maybe I'm just barking up the wrong tree. But for what it's worth, I went through the motions of adding the Jellyfin user to the video group and selecting V4L2 from the dropdown.

I also tried using Handbrake to pre-transcode the video file, but honestly, I have no idea what I'm doing with that. I don't mind if I have to pre-transcode chunks of my library, Handbrake has a good batch interface and I can just leave it running for a few hours or days on my workstation if needed (I download files to my desktop so I can vet them for quality and subtitles before synchronizing them to my libraries on the Pi). But the problem is that it didn't seem to make much of a difference.

Assuming there's nothing else I can do to squeeze the necessary performance for transcoding out of my Pi, can anyone recommend some good settings to properly configure Handbrake to pre-transcode video files that the Pi can digest more easily?

Thanks, everyone! I love Jellyfin!!

[TheDreadPirate]

Hardware acceleration is pretty much broken on the RPi. Your best option if you are going to stick with a RPi as the server is to re-encode everything with H264 Main, 8-bit video, AAC audio, and burned in subtitles. This should pretty much eliminate the need for transcoding for most devices.