Video conversion with GPU only. Is it possible?

[Nitobert]

So here’s my situation:

I have a custom built Plex server that I also use for video conversion.

I personally don’t like plex’s subtitle support. So movies I aquire that have forced subtitles, I like to burn them in ahead of time.
By doing this I can save my servers CPU transcoding resources for other needs.

My question:

Is there conversion software that will only use my GPU and not the CPU?

I would also need this software to support HDR aka BT.2020

Thank you in advance!

[LigH.de]

If you want a GPU encoder, you want lower quality than the best available CPU encoders.

Apart from that, it's indeed possible that GPU vendors already provided video converters which use both the decoder and the encoder on the GPU (e.g. in case of Nvidia, PureVideo + NVEnc; or an intel converter using QuickSync for both GPU decoding and GPU encoding). But such converters will be very simple, if they exist at all. I really doubt they care about colorimetry.

I could imagine that Selur's Hybrid may support both separately, but the video would take a detour over RAM and CPU between both stages here.

[blud7]

You can burn in subtitles with StaxRip which also supports GPU only encoding via Nvenc (which you can update manually to the latest version).
If you have a decent NVIDIA CARD you can have excellent, quick results, similar to fast settings say using x264 eg
BUT...CPU still beats GPU for quality.
AMD encoder still sucks.