I installed LibreELEC on a Raspberry Pi 4 yesterday and it's working really well, except for AV1 playback. The thing is, it's almost fast enough but the video stutters every few seconds and is a little slower than it should be. Is there a way to make it faster, by switching the decoder or enabling multi-core decode or something like that?
I found this decoder which might be what I'm searching for but I don't know how to make it work in LibreELEC.
It's the usage of all 4 cores added together, so the maximum is 400%
Oh, makes sense now 😂.
Wow, that is a lot. All 4 cores are at almost max... and not even passive cooling... that can be a problem.
Hm, have you tried compiling it natively? Like for best optmization. Maybe add some hardware switches to make/cmake/whatever-it-uses-for-building?
I'll probably buy the Flirc case so it has some passive cooling. Temperatures are fine tho, it's at around 82-83°C.
Does compiling natively with extra optimizations make a noticable difference? Might try that.
+80C is just asking for trouble if you ask me... I wouldn't be comfortable with anything above 70C.
But, than again, I don't own a Pi, so I wouldn't know. Maybe working in the middle of the second half of the 100C mark is normal for a Pi 🤷.
In some cases, yes. Codecs are known to greatly increase performace if adequate CPU optimizations are used. Don't know what ARM uses, but AVX, AVX2, SSE3, etc. on Intel CPUs does significantly increase performance in codecs. It's mostly noticable when encoding, but it helps decoding as well (not to the extent that it helps in encoding though, but adequate switches when building can reduce CPU usage when decoding by about 10 to 20%... which should help a lot in your case).
But, you have to compile the software with those switches, otherwise, it won't use the optimizations 🤷.
If you can, also have a look at the build scripts of the AV1 binary/library, see if they used CPU specific optimizations or not. Maybe they did, maybe they didn't 🤷.
I want to try compiling it with those optimizations and I found this Reddit post, which explains how to do it. I'm not sure if just compiling and installing it is enough to make LibreELEC use it tho.
If it needs that library to work, then yes, compiling it and installing it is all it takes. Also, make sure it's installed in the right place. If it isn't, symlink it to where LibreELEC wants it to be.
Make a package of the library after compiling it... or if you can't make one, make a snapshot of the OS before installing it, so you can bring everything back the way it was in case something goes wrong.