[FFmpeg-devel] [PATCH] Sync the NTP timestamps for RTP streams

[Martin Storsjö]

On Tue, 9 Mar 2010, Martin Storsj? wrote:

> On Tue, 9 Mar 2010, Luca Barbato wrote:
> 
> > On 03/08/2010 11:52 AM, Luca Abeni wrote:
> > > Martin Storsj? wrote:
> > >> As discussed earlier, the NTP timestamps in RTCP sender reports are
> > >> used to sync multiple RTP streams together. If first_rtcp_ntp_time in
> > >> RTP muxers differ, though, the individual streams get out of sync.
> > > [...]
> > > 
> > > [...]
> > >> The attached patch series is an attempt at this. First the ntp_time
> > >> function is made public, since the caller (be it the RTSP muxer or an
> > >> external libavformat user) will need it to set coordinated NTP start
> > >> timestamps. Is this ok, or should it be ff_ prefixed and left internal
> > >> to libavformat for now?
> > > 
> > > I am not sure if we want a public av_ntp_time() function. I'd be
> > > inclined to go for a private ff_ntp_time(), but I'd like to hear
> > > other people's opinions too.
> > 
> > I think it could have some uses outside, yet it's quite simple so either
> > way won't cause much harm.
> 
> Well, the one use outside would be for setting a sane value for the 
> coordinated start time. But I'm ok with keeping it private for now, since 
> it's simple to reimplement outside if needed anyway.

Updated patch series, made the ntp_time a libavformat internal function 
with an ff prefix, still using metadata for passing the data. Added an 
RTP: prefix to the metadata key.

// Martin
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