[FFmpeg-user] Seeking guidance on debugging rtsp copy to file

[Moritz Barsnick]

Hi Rich,

On Thu, Jan 09, 2020 at 11:26:26 -0500, Rich Andrews wrote:
> So it appears to me that ffmpeg is probably working properly and that the
> RTSP stream maybe goes away on the network.

If that's the case, there's not much I can help with; but:

> So my questions could probably have been more brief, "What other debugging
> techniques can be applied to introspecting the state of ffmpeg?".   I'm
> guessing it has something to do with the RTSP stream, RTSP signaling and
> the WLAN.   But maybe more experienced eyes will see something here and
> help provide some guidance as to what I can do from ffmpeg's point of view.

You've already done a lot of your homework, apparently. For similar
debug, /proc and strace would have been two places for me to check.

Additionally, I would attach gdb to the running ffmpeg process, and
figure out where each thread is currently operating.

I would also attach tcpdump / wireshark to see the network packet flow
(which apparently ceases in your case, so nothing gained there).

I would also try "-f null" output, in order to see whether the issue is
truly on input side.

And I would try a different RTSP client, to see whether the same issue
appears.

I might come up with more, but these quickly come to mind.

Cheers,
Moritz