I have an i5-3470T with QuickSync (HD2500). I’m trying to hardware transcode from HEVC to H264.
After review, it looks like plex is opting to use libx264 instead of h264_vaapi after it attempts the decode and figures out that the HD2500 driver doesn’t have HEVC support.
It looks like part of the command line is even left: “-vaapi_device /dev/dri/renderD128”
What I would like to happen is a software decode of the HEVC and a hardware encode of H264 using the h264_vaapi codec.
Has anybody had any similar experiences?
Oct 23, 2018 00:18:02.908 [0x7f95483f8700] ERROR - [Transcoder] [hevc @ 0x30928c0] No support for codec hevc profile 2.
Oct 23, 2018 00:18:02.909 [0x7f9549bfb700] ERROR - [Transcoder] [hevc @ 0x30928c0] Failed setup for format vaapi_vld: hwaccel initialisation returned error.
I totally understand that the CPU doesn’t support decode of HEVC.
My concern is why can’t plex pick up that that the hardware isn’t capable of decoding HEVC in hardware, and still be able to encode h264 using quicksync?
I can do the same with FFMPEG directly on the same PC. something like: “ffmpeg -i input.mkv -vcodec h264_vaapi output.mkv” (where input.mkv has a HEVC stream)
Libx264 is software because it has detected there is no HEVC support.
Because there is no direct HEVC -> H264 support (native in the -6xxx and above) which is zero-copy mode, it has selected software. This is how engineering decided to handle it.
