[speex-dev] @Christian Buchner: speex acm & netmeeting

Christian Buchner Christian.Buchner1 at epost.de
Fri Jul 25 01:40:17 PDT 2003



> Yes! It works! I tried mono 8kbit 8khz Q3 and it seems to work! I am 
> currently talking to a friend, both ends using Speex!
> Sound Quality is not as good as speeak freely at adpvm, but it uses only 
> quarter of bandwidth and for that the quality is not bad. Perhaps I'll 
> try Q4, as well.

Q4 and Q3 seem to produce the same results. Internally speex is controlled
by tables defining coding parameters for various quality levels. In this
case there is no difference between 3 and 4.

Here's the 16 bit Mono mode list

           79, 320,	8,	3950,	// 16000 1 0
          115, 320,	8,	5750,	// 16000 1 1
          155, 320,	8,	7750,	// 16000 1 2
          196, 320,	2,	9800,	// 16000 1 3
          256, 320,	1, 12800,	// 16000 1 4
          336, 320,	1, 16800,	// 16000 1 5
          412, 320,	2, 20600,	// 16000 1 6
          476, 320,	2, 23800,	// 16000 1 7
          556, 320,	2, 27800,	// 16000 1 8
          684, 320,	2, 34200,	// 16000 1 9
          844, 320,	2, 42200,	// 16000 1 10

As you can see Q4 and Q5 are good candidates providing one
frame per block at rates of 12800 and 16800 bits/sec.

The fact that your mode registered twice may be because you may
have forgotten to unregister your previous attempt ;) There is
a separate API call to remove a codec from Netmeeting again.

Christian

--- >8 ----
List archives:  http://www.xiph.org/archives/
Ogg project homepage: http://www.xiph.org/ogg/
To unsubscribe from this list, send a message to 'speex-dev-request at xiph.org'
containing only the word 'unsubscribe' in the body.  No subject is needed.
Unsubscribe messages sent to the list will be ignored/filtered.



More information about the Speex-dev mailing list