Question regarding VP9 capabilities

Hi everyone,

I hope hope you had a great start into the new year.

I have a question regarding the capabilities of the Vero 4K/4K+ regarding the VP9 codec. I noticed while watching Youtube that some videos seem to continiously skip frames. I think I have narrowed it down videos with a 4K resolution playing at 59.94 fps (or higher?).

Is the Vero 4k to underpowered for VP9 4K 60 upwards?

Searching for a youtube test clip I used this

I can reproduce the behaviour outside of youtube with VP9 Profile 2 HDR 59.94fps The World in HDR Sample from the Kodi Wiki sample page (Kodi Samples #25)

The Vero is connected to a LG CX through a Denon X2400H.

Log: https://paste.osmc.tv/guwolejuje

Cheers,
NoDruid

Yes, I’m getting skips with VP9 4k60 files, even when played from a local SSD. I haven’t noticed this before so don’t know if it’s a recent thing.

A certain amount of frame skipping on 4K 60fps stuff (including VP9.2) has been happening for a long time. I think it may have got worse with the move to the 4.9 kernel, but it’s not a recent thing.

@NoDruid Make sure subtitles are turned off, and that you’re not displaying any sort of overlay (such as the display for how many frames have been skipped!) - that helps a bit.

You’re right. I can’t actually see any skips if I turn the OSD off.

FWIW: negligible skips on Vero V :smiley:

It’s in spec

If you play through the whole video with no overlay, pause it at the end, then bring up the “frames skipped” display, it will show a few missing frames (and they’re visible to the naked eye at the time!). YouTube stuff isn’t as skippy as 4K 60fps h.265 is, but you do still lose a bit.

I can see that on Vero 4K/4K+ here but not on Vero V.

Sorry for the late reply. Thanks for all your feedback. I normally have the osd stuff and subtitles off, I only enabled it to investigate what was going on.

The reason I came up with the question was an extreme case where the skipped frames were in a few ten thousands in a video and it was very choppy. Unfortunately this was before the holidays and I can’t seem to remember which video it was exactly. I am still looking. The closest I got for similar behaviour was the mentioned 4k 60 videos. But as you said while they show a similar problem, it was never near that bad.

I know Youtube is third party app, so this is not your purview. But I thought a post might be worth it, maybe someone else stumbled upon the same thing. And if not just to exclude the possiblity that the use case was out of spec and wasting a lot of time looking for the problem in the wrong place. The last part @sam_nazarko answered here, so I learned something already. Thanks for that.

It appears that some of the frameskipping at least in the youtube app was cache related. Because when I increased the cache in the youtube app from 50 MB to 100MB the skipping seemingly decreased. I would try to increase it further for testing but 100MB seems to be the limit in the application.

This is not a high priority just something I stumbled upon. If I should find a video again I will be smarter and save it, so it is reproducable. For now this appears to have been an absolut edge case.

I thank everybody for their time, I hope I did not waste to much of it.
You guys do an awesome job and it is a great device. Keep up the good work.

Have you disabled the AV1 codec? If it’s trying to play an AV1 video, that won’t go well.

Yes. The AV1 Codec is disabled.