H/W Accelerated H264 Decode / Encode (V4L2)

#21

Some comments:

The Mali G31 GPU used with S905Y2 has excellent support in the upstream kernel, but that has nothing to do with H264/HEVC/VP9/etc. as Mali is purely a 2D (GUI) accelerator, it doesn’t process video.

There is reasonable upstream support for 8-bit/1080p H264/HEVC/VP9 if you use the right kernel and ffmpeg sources, and S905Y2 will happily software decode those and all legacy formats to the same specs. Decoding 10-bit and 4K is not possible right now due to unresolved bugs. Fixing issues in the current upstream (and submitted) code will be considerably quicker then attempting to port the vendor code (which is written around Amlogics homebrew DRM frameworks).

There is no support for Anlogic V4L2 encoding in the upstream kernel, but Amlogic’s encoders aren’t that good so it’s not a big loss. You will get better results software encoding with ffmpeg or gstreamer.

#22

Thank you, @chewitt for the clarification.

#23

Hey guys, I stumbled upon your replies just a moment ago. From my experience :

  • CoreELEC 20 provides the best video reproduction, obviously because it’s the only OS that still ships with the initial proprietary video drivers
  • CoreELEC 21 ships with the bleeding-edge open-source video drivers that aim at replacing the former
  • H264 decoding and display is far better with CoreELEC 21 than with Manjaro (or at least was a few months back). But it’s still not on par with CoreELEC 20 - frame drops still occur from time to time, and the beginning of sequences can be noisy

That’s about it for what I can say !

#24

You can try libreElec.

Its still not perfect though.

#25

Oh I tried LibreElec at the same time, and it wasn’t as advanced as CoreElec specifically on the hardware video decoding subject. Nevertheless, excellent distro for its specific usecase. I have seen that the relations between the two teams are not totally fluid. Still I’m very grateful to both projects, as CoreElec managed the best open-source distro using the video drivers of this processor, and it could not have existed as such if there wasn’t LibreElec to build upon. Hail to both projects ! Keep it up guys !

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