added comments about jitter/playout buffers

git-svn-id: http://svn.berlios.de/svnroot/repos/sems/trunk@520 8eb893ce-cfd4-0310-b710-fb5ebe64c474

core/AmJitterBuffer.cpp

@@ -30,6 +30,15 @@
 #include "log.h"
 #include "SampleArray.h"
 
+//
+// Warning: 
+// This jitter buffer seems to increase the buffer size, if jitter (delay variation) is 
+// present in the stream, or for example a temporary delay spike is detected, 
+// but it does not adapt the buffer to shrink again if the situation has improved. 
+// The adaptive playout buffer method usually shows much better results
+// in minimizing the total playout delay (using more processing power though).
+//
+
 bool Packet::operator < (const Packet& p) const
 {
   return ts_less()(m_ts, p.m_ts);

core/AmPlayoutBuffer.cpp

@@ -122,6 +122,14 @@ void AmPlayoutBuffer::buffer_get(unsigned int ts, ShortSample* buf, unsigned int
     r_ts = ts + len;
 }
 
+//
+// See: Y. J. Liang, N. Farber, and B. Girod. Adaptive playout scheduling 
+// and loss concealment for voice communication over IP networks. Submitted 
+// to IEEE Transactions on Multimedia, Feb. 2001. 
+// Online at: 
+//  http://www-ise.stanford.edu/yiliang/publications/ 
+//  http://citeseer.ist.psu.edu/liang02adaptive.html 
+// 
 AmAdaptivePlayout::AmAdaptivePlayout(AmPLCBuffer *plcbuffer)
   : AmPlayoutBuffer(plcbuffer),
     idx(0),