[FFmpeg-user] Trying to stream to rtmp from my rsp4 and a GoPro

[Carl Eugen Hoyos]

Am So., 14. Feb. 2021 um 22:27 Uhr schrieb Mike Soultanian
<mike at soultanian.com>:
>
> On 2/14/2021 12:40 PM, Carl Eugen Hoyos wrote:
>
> >> Should ffmpeg be able to capture from any capture card
> > Only video4linux2 is supported, how well it works depends
> > primarily on the kernel driver.
> >
> > You probably want a card that provides data in a pix_fmt
> > that your hardware encoder supports.
>
> If I'm understanding correctly, this would be what you refer to *yuyv422*?

I was thinking about yuv420p but I don't know how you want to encode
(and what you plan to do with the resulting file).

> It would seem like both my capture card and my logitech support
> the same formats, but the logitech 920 also lists h264 (listed below)
> - is that why it's allowing it to work?

That's completely unrelated but has the advantage that you don't have
to encode.

> What I don't understand is why I'm able to record either video or audio
> from the capture card, but when they're both together it's not happy.

How should FFmpeg mux audio and video if one has timestamps
starting with 0 and the other with 10000000?
You can - easily - let the audio stream start with 0 but the problem
is that the result will not play in-sync, see the setps documentation.

Carl Eugen