[FFmpeg-soc] [PATCH] RTCP BYE

[Martin Storsjö]

On Sun, 15 Aug 2010, Ronald S. Bultje wrote:

> On Aug 15, 2010, at 5:34 AM, Luca Barbato <lu_zero at gentoo.org> wrote:
> > On 08/15/2010 10:58 AM, Josh Allmann wrote:
> >> 0002 - Reinstate rtp_get_file_handles function that is slated for
> >> removal at the next major bump. We need to be able to get the RTCP fd
> >> from the rtpproto.
> > 
> > Ok
> 
> Can we instead introduce a rtp_get_rtcp_file_handle()? I removed the _handles() one, it's not good API.

I'm ok with it either way. So a separate function for RTCP it is, then?

> >> 0003 - Read RTCP packets from the RTSP demuxer. This might not be
> >> strictly necessary, but it guarantees we'll read a RTCP packet if one
> >> is available (without the availability of a RTP data packet).
> > 
> > Ok, maybe you can factorize it a bit better on a later time.
> 
> This woyld need to be factorized to support RDT status msgs, which happen over the actual RDT line.

Is RDT received over rtp:// URLContexts? If that's the case, this patch 
itself still is ok, you just won't ever get any data on the RTCP socket.

> >> 0005 - Actual BYE support. This is really kinda incomplete. It only
> >> returns EOF, whereas we should be selectively removing the stream
> >> (theoretically we could have concurrent streams playing, and one BYEs
> >> while the others keep going). In the case where we get a BYE with only
> >> one stream left, perhaps an EOF would be appropriate then.
> > 
> > Not sure when that would happen, seems unlikely enough to not be
> > considered now.
> > 
> >> Right now, not much happens since the EOF is propagated back to the
> >> application layer. FFplay pretty much ignores it, although I suppose
> >> it could (should?) be patched to call av_close_input_stream, so it
> >> sends a proper TEARDOWN.
> > 
> > Yup, it should do that, I wonder where the eof is lost.
> 
> Teardown means no seek support after EOF, i.e. this behaviour is intentional. The teardown should only be sent on close. EOF really isn't special, it just stops getting more packets (= infinite loop)unless the user has done something (seek, close).

As Ronald said in another message, use -autoexit with ffplay if you want 
it to close the app at eof.

I'm a bit undecided on how to handle this, if we should return EOF when 
the first stream sends BYE, or only when we've got that on all streams?

Josh, does the main servers (DSS, feng) send BYE at eof on all streams at 
the end? Does DSS send BYE properly on live streams, too?

If all send BYE on all streams properly, perhaps we should wait for them 
all. On the other hand, in normal RTSP at least, all streams exist for the 
full duration of the stream (I think?), so you don't have to worry about 
the case when one stream is finished but another one still is playing 
properly for a longer time.

// Martin