Support for hardware decoding with VA-API

[vr7bd]

Hey guys, I noticed that livekit currently supports hardware accelerated video encoding on Linux, but not hardware accelerated video decoding (based on the absence of vaapi_decoder_factory).

Are there any plans of implementing? If not, I would love to contribute, although I would need some guidance.

The README says that hardware encoding and decoding is supported only on MacOS with VideoToolbox and NVIDIA/AMD GPUs on Linux. Does that mean encoding and decoding is not supported on Intel hardware? Because VA-API is an Intel thing and the presence of vaapi_encoder_factory would mean that there is hardware encoding support on Intel hardware.

Also, is there any plan to support hardware encoding and decoding for VP8/VP9?

Thanks a lot!