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<div>Does anyone have any feedback about the following change (which
was put into place for the most recent version of the code)? A
few months ago, several people were complaining about the high bitrate
of 'trick play' streams (fast-forward or reverse play) for Transport
Stream data. Does this new version of the code work better for
you?</div>
<div><br></div>
<div><x-tab> </x-tab>Ross
Finlayson</div>
<div><x-tab> </x-tab>Live
Networks, Inc.</div>
<div><br></div>
<div><br></div>
<blockquote type="cite" cite>Date: Mon, 23 Feb 2009 20:20:33 +1000<br>
To: live-devel@lists.live555.com</blockquote>
<blockquote type="cite" cite>From: Ross Finlayson
<finlayson@live555.com></blockquote>
<blockquote type="cite" cite>Subject: Change to 'trick play' Transport
Stream generation - reduces output bit rate</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite>Some people have reported having problems
with 'trick play' operations on Transport Streams, due to the high
bitrate of the 'trick play' output streams.<br>
<br>
By popular demand, I have now released a new version (2009.02.23) of
the "LIVE555 Streaming Media" software that changes the way
that Transport Streams are generated for 'trick play' operations
(fast-forward or reverse play). Now, each I-frame (i.e., key
frame) appears no more than once in the output Transport Stream for
'trick play' operations. This will have the effect of reducing
the average output bitrate for 'trick play' streams, except for high
'scale' values.<br>
<br>
For those of you who have been having problems with the high bit rate
of 'trick play' Transport Stream data - please try this new code, and
let us know if this new version of the code improves things.
Note that because these changes are experimental, I have not yet
changed the prebuilt binary versions of the "LIVE555 Media
Server" application - therefore, if you use this application, you
will need to build your own version from the new source code.<br>
</blockquote>
<blockquote type="cite" cite>If - for whatever reason - you wish to go
back to the old behavior (in which we always keep the original frame
rate, even if it means duplicating I-frames), then you can do so by
changing the definition of "KEEP_ORIGINAL_FRAME_RATE" in
"liveMedia/MPEG2TransportStreamTrickModeFilter.cpp" to
"True". However, if you find you need to do this,
please let us know why. This change to the code is experimental,
and I will back it out if people end up having problems with
it.</blockquote>
<blockquote type="cite" cite><tt>-- </tt></blockquote>
<blockquote type="cite" cite> </blockquote>
<blockquote type="cite" cite><br>
Ross Finlayson<br>
Live Networks, Inc.</blockquote>
<blockquote type="cite" cite>http://www.live555.com/</blockquote>
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