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<DIV><FONT face=Arial color=#800000 size=2><SPAN class=660321018-08012001>You
are right. This looks like a mistake in Annex F/H.323. It should say "# of
frames" in the diagram and in the text below. The current text conflicts with
the rest of H.323 and H.225.0 and H.245.</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#800000 size=2><SPAN
class=660321018-08012001></SPAN></FONT> </DIV>
<DIV><FONT face=Arial color=#800000 size=2><SPAN class=660321018-08012001>Paul,
another one for the implementor's guide?</SPAN></FONT></DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #800000 2px solid; MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B> stefan Jung
[mailto:stefan.jung@dsp.se]<BR><B>Sent:</B> Monday, January 08, 2001 1:16
AM<BR><B>To:</B> H.323 Implementors<BR><B>Subject:</B> OpenLogicalChannel
parameter<BR><BR></FONT></DIV>
<DIV><FONT face=Arial size=2>Hi All,</FONT></DIV>
<DIV><FONT face=Arial size=2>I need help with the intepretation of a parameter
in the Open Logical Channel structure.</FONT></DIV>
<DIV><FONT face=Arial size=2>The problem I have is when i read the AnnexF
specification. In the AnnexF chapter 10.1.1.1 there is a layout of the
logical channel structure that shall be used by the SET device for the codecs
G.711 and G.729. In the structure there is a parameter denoted "# samples".
</FONT></DIV>
<DIV><FONT face=Arial size=2>The definition is : For codecs G.711 A law
64 kbit/s, G.711 56 kbit/s u law 64 kbit/s, ulaw 56 kbit/s and G.729
Annex A this component contains the number of samples -1 per audio packet as
defined in H.245.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>The problem with this definition is that it is
not specified in that way in H.245. In H.245 it is stated that all saple based
codecs are considered as frame based with a frame length of 1 ms.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>So how shall the "#samples " be interpreted
?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>If it is actually samples then the maximum
value seems a bit small.</FONT></DIV>
<DIV><FONT face=Arial size=2>The parameter is 8 bits which gives a maximum of
256 samples. This corresponds to 32 ms in G.711.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>A more reasonable interpretation would be to
consider the parameter as "frames" instead. This would then give a more
flexible range of the packet size and it would fit better with the definitions
of H.245.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Any input to clarify would be
appreciated.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Best regards</FONT></DIV>
<DIV><FONT face=Arial size=2>/Stefan Jung</FONT> </DIV>
<DIV><FONT face=Arial size=2> </FONT></DIV></BLOCKQUOTE></BODY></HTML>