Laurent,

> While I agree with you, we have a problem here. The V4L2 specification
> mandates the use of gettimeofday() to fill the v4l2_buffer::timestamp field:
>
> http://www.linuxtv.org/downloads/video4linux/API/V4L2_API/spec-
> single/v4l2.html#v4l2-buffer
>
> I'll discuss this with core V4L2 developers.
>

Thank you, btw I've tested uvc v4l2 buffer timestamps with
gettimeofday and with ktime_get, and taking the first frame as
reference, ktime_get  proved much more steady.
While for gettimeofday (at 30 fps), I got anything from 28 ms to 40 ms
between frames in a totally random sequence, for ktime_get, I allways
got a steady 32 ms, 32ms, 36ms, 32ms, 32ms, 36ms.
The only explanation I could find is that my quad cores have the TSC
out of sync, since in a single core machine both methods seemed
equally steady.

Best regards,
Paulo
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