h264 v4l2 zoom configuration

[cpinflux]

I have this "working" for zoom streaming using either rawvideo or mjpeg codecs, however rawvideo looks terrible by the time it reaches remote clients, massively compressed by zoom to be unusable. using mjpeg is almost acceptable but it's compression, whilst fine for actual camera video, looks very ropey. It seems that h264 is the solution, but i can't get any combination i try working.

e.g.

$ wf-recorder -f /dev/video10 --muxer=v4l2 -d /dev/dri/renderD128 --codec=h264_vaapi --pixel-format=yuv420p -g "0,0 1920x1080"
using VA-API, trying to enable DMA-BUF capture...
region capture not supported with DMA-BUF
Detected output based on geometry: HDMI-A-1
selected region 0,0 1920x1080
Failed to find AV format for0Using video filter: hwupload,scale_vaapi=format=nv12:out_range=full
Impossible to convert between the formats supported by the filter 'Parsed_scale_vaapi_1' and the filter 'auto_scale_0'
Failed to configure graph filter: Function not implemented

I can't deny my knowledge of video formats here is lacking to say the least, but any pointers on, I'm guessing, the magic filter string needed here so I can have a decent looking, but compressed, video stream for Zoom.