[GnomeMeeting-list] speex-8kps using > 24kbs?



When I tried the speex-8k codec, it turns out that gnomemeeting
sends each speex frame (20ms, 20 bytes) in a single UDP package 
(with >= 28 bytes overhead), and somewhere also adding another 
12 bytes (ogg headers??)

So, for every 20 bytes of speex data, a IP package of 60 bytes
is sent, using 24kbps of IP traffic (and 26kbps ppp traffic,
if sent over a ppp link)

I've increased the "minumum jitter buffer" setting to 100ms,
even 500 ms, on both ends, hoping that the higher latency may
persuade gnomemeeting to put more frames in each UDP package,
but gnomemeeting still sends a package every 20ms.

The phoneline I would like to use gnomemeeting over really
doesn't handle 24kbps. And, after using gnomemeeting 
during some time with a round-trip-time of about 
1 second (I guess a result of a link getting saturated),
I found it quite usable.
So, it seems I begin able to be able to get more speex 
frames in each IP package would really help me.

When I saw that ohphone had the same behaviour (using >24kbps
for speex-8k), I (wrongly) concluded that this was a speex
limitation, but I was quickly corrected:

http://www.xiph.org/archives/speex-dev/200312/0011.html
http://www.xiph.org/archives/speex-dev/200312/0012.html

Are there any plans on making the number of speex frames
in each package custumisable? Would patches be appreciated?
(I've tried looking at the source, but, really, up until
now I haven't been able to really figure out where to begin).


Oh, and about me suppozing that gnomemeeting puts ogg headers
in each package sent. This was based on theses observations
  - 20ms of 8kbps data is 20 bytes, each IP package was
    60 bytes long, with 28 bytes of IP/UDP headers, that
    leaves still 12 bytes unaccounted for. 12 bytes happens
    to be the size of the ogg headers.
  - when looking at tcpdump -x output, I noticed that more
    than the first 28 bytes were static (except checksums),
    and attribute those to ogg headers.
Anyway, does gnomemeeting add ogg headers?


Thanks,
joostje



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