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Re: I found there are more than 7 seconds time delay beteen the real live

Another try: I also installed Quicktime Broadcaster on OSX and annouced a
live video
to local QTSS. I found there are more than 7 seconds time delay beteen the
real live
video and the qt player. Is that normal? (We used LiveChannel on OS9.2
before,
and it has only about 3sec delay. We thought using instant-on feature on qt6
and
0 buffer on QTbroadcaster should elimidate that 3sec delay.)
I think I must have some wrong configuration but couldn't get it...


First, there are actually two different possible sources of delays at work here.
Let me explain:

1) A delay on the QT Client form the time you open the RTSP url to the
time that you start actually seeing the QuickTime stream being rendered.

The "Instant on" streaming feature that was introduced with QTSS 4.1 + QuickTime 6
does reduce #1 (above), for both Stored and Live video for broadband connections.

2) A delay (latency) between "real-time" video vs. what the QT Client sees (reflected)
(ie. you snap your fingers in front of the live broadcaster camera, and then watch on
your connected QuickTime Player to see the same finger snap happen)

As for #2 above (latency), this is mostly due to the amount of "skip protection" and overbuffering
that the Streaming Server is providing for the live reflected stream. At the cost of increasing the
real-time latency, the Streaming Server is able to not only provide a better "instant on"
response, but the server is also able to provide "skip protection" which handles retransmits
of data (as necessary) to help improve the quality of the stream and avoid packet-loss.

When you were seeing lower latency with LiveChannel on OS9.2 before, I suspect there wasn't
any "skip protection" or overbuffering of the live stream and that you were using a version of
QTSS prior to 4.1 (which does support"skip protection" of live streams).

--
Billy Brown
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References: 
 >Re: Performance difference of QTSS on RH and OSX (From: Chong Zhang <email@hidden>)



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