Accelerated Video Decoding

[fergal]

I've been looking around for instructions to make video decoding work well and I've found a very old thread recommending to use a custom kernel but that's 2017.

I also found Sunxi Cedrus docs that make it sound like a lot of this stuff is up-streamed in newer kernels.

So does it work at all? Are there any good, clear docs on what I'm supposed to do to get accelerated video decoding?

Thanks.

[LubOlimex]

I can't say if it works, nor point you to any documents. Our engineers couldn't get it it working.

If we could get the video decoding with mainline images, we would've done it and published the guide and had it available in our official images.

Maybe you can get it working and we can use your feedback.

[fergal]

TL;DR Some stuff seems to work but I know too little to judge whether it's really working.

The instructions here seem to be working. Specifically

Code Select Expand

systemctl stop lightdm
# log out of any X session
v4l2-request-test

plays back frames nicely and with -ql plays them back much faster than 25fps.

Also (with X running again), after adjusting vlc's settings

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vlc --fullscreen big_buck_bunny_1080p_H264_AAC_25fps_7200K.MP4

plays nicely (although CPU usage is about 200%-300%).

I tried another H264 video file and it was awful. I'm coming to this as someone who knows nothing about video stuff, so I have no idea what's different between that and Big Buck Bunny.

Maybe BBB is just easy to decode and it's happening in CPU.