[xiph-commits] r10737 - trunk/theora/doc

[lu_zero at svn.xiph.org]

Author: lu_zero
Date: 2006-01-17 11:52:07 -0800 (Tue, 17 Jan 2006)
New Revision: 10737

Modified:
   trunk/theora/doc/draft-barbato-avt-rtp-theora-00.xml
Log:
Video Stream section added

Modified: trunk/theora/doc/draft-barbato-avt-rtp-theora-00.xml
===================================================================
--- trunk/theora/doc/draft-barbato-avt-rtp-theora-00.xml	2006-01-17 19:12:07 UTC (rev 10736)
+++ trunk/theora/doc/draft-barbato-avt-rtp-theora-00.xml	2006-01-17 19:52:07 UTC (rev 10737)
@@ -962,9 +962,28 @@
 
 </section>
 -->
+<section anchor="Stream Video" title="Stream Video">
 
+<t>That is one of the most common situation: one single server streaming content in multicast, the clients may start a session at random time. The content itself could be a mix of live stream, as the wj's voice or studio scenes, and stored streams, as the music she plays.</t>
+
+<t>In this situation we don't know in advance how many codebooks we will use. The clients can join anytime and users expect to start the fruition of the content in a short time.</t>
+
+<t>On join the client will receive the current Configuration necessary to decode the current streams inlined in the SDP so that the decoding will start immediately after.</t>
+
+<t>When the streamed content changes the new Configuration is sent in-band before the actual stream, and the Configuration that has to be sent inline in the SDP updated. Since the inline method is unreliable, an out of band fallback is provided.</t>
+
+<t>The client could choose to fetch the Configuration from the alternate source as soon it discovers a Configuration packet got lost inline or use <xref target="RFC3611">selective retransmission</xref>, if the server supports that feature.</t>
+
+<t>A serverside optimization would be to keep an hash list of the Configurations per session to avoid packing all of them and send the same Configuration with different Ident tags</t>
+
+<t>A clientside optimization would be to keep a tag list of the Configurations per session and don't process configuration packets already known.</t>
+
+<t>Let's assume that the client playout buffer can store at least 7 packets for each stream.</t>
+
 </section>
 
+</section>
+
 <section anchor="Security Considerations" title="Security Considerations"> 
 <t>
 RTP packets using this payload format are subject to the security considerations discussed in the RTP specification