[vlc-devel] [PATCH] live555: fix the subtitles issue

Rémi Denis-Courmont remi at remlab.net
Mon Dec 30 14:37:54 CET 2013

Le lundi 30 décembre 2013, 12:55:12 Gilles Chanteperdrix a écrit :
> > I'm not sure what you mean by 'time out' in this case, but, no.

OK, my mistake.

> Well, in the case of NAT, it does, the router closes the port after not
> receiving packets for some time (around 30s in my case), so that when
> unpausing a paused stream, vlc does not receive anything.

You _cannot_ use RTSP with unicast UDP behind a NAT (unless the NAT has an 
RTSP ALG). Period.

> I have submitted a patch to live555 to resend dummy packets when unpausing
> a stream, in order to reopen the ports, but I have no idea of what it
> became ;-)

This is silly. There is no way to determine what the outer source port will 
be. And even if you knew what the port was, say with a cone NAT and a STUN 
server, if the NAT flow timed out, there is no warranty that the port will be 
the same as before pause.

If you are behind a NAT (without ALG), use Interleaved TCP.

Rémi Denis-Courmont

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