[PATCH] v4l2src: Allow to set `V4L2_MEMORY_FLAG_NON_COHERENT`
Setting this flag can improve speed significantly for purely software based transformations.
E.g. conversion rate for bayer2rgbneon on an iMX8MP and 1920x1080 is increased from 12 fps to 110 fps.
Tested with
gst-launch-1.0 --no-position v4l2src device=/dev/video1 force-aspect-ratio=false '!' \
video/x-bayer,width=1920,height=1080,format=bggr,bpp=8 '!' \
bayer2rgbneon show-fps=t reduce-bpp=t '!' \
fbdevsink sync=false
FPS: conv 12.1, stream 11.4
gst-launch-1.0 --no-position v4l2src device=/dev/video1 force-aspect-ratio=false use-non-coherent=true '!' \
video/x-bayer,width=1920,height=1080,format=bggr,bpp=8 '!' \
bayer2rgbneon show-fps=t reduce-bpp=t '!' \
fbdevsink sync=false
FPS: conv 110.7, stream 30.6
0001-v4l2src-allow-to-set-V4L2_MEMORY_FLAG_NON_COHERENT-h.patch