[Telepathy] change speexenc settings for empathy

[Alexey Fisher]

Hallo all,

i currently play with speex settings. My conclusion is: speexenc is sort
of bad with default options. 

Here is my reconfigured pipeline:
gst-launch pulsesrc device=0 ! audio/x-raw-int, rate=16000, channels=1 !
speexenc vbr=1 dtx=1 nframes=4 ! rtpspeexpay ! udpsink port=5555
host=192.168.0.155

In my tests, if i use speexenc without any option, network usage is 50
kbit/s. If i use "speexenc vbr=1 dtx=1 nframes=4", network usage is
about 25 kbit/s without noticeable quality regression.

Options description:

vbr=1
# enable variable bitrate 

dtx=1
# do not send any packets on silence
# see Bug https://bugzilla.gnome.org/show_bug.cgi?id=646474

nframes=4
# allow better compression and bigger packet size. It reduce network
# traffic to 13 packets/sec. (with default options ~50 packets/sec).
# the value bigger than 4 will introduce stuttering. 

====================================================================
Pipes for testing:

source:
gst-launch pulsesrc device=0 ! audio/x-raw-int, rate=16000, channels=1 !
speexenc vbr=1 dtx=1 nframes=4 ! rtpspeexpay ! udpsink port=5555
host=192.168.0.155

sink:
gst-launch udpsrc port=5555 caps="application/x-rtp,
media=(string)audio, clock-rate=(int)16000, encoding-name=(string)SPEEX,
encoding-params=(string)1, payload=(int)110" ! gstrtpjitterbuffer !
rtpspeexdepay ! speexdec ! pulsesink

====================================================================

Now the question:
how can i change speexenc settings for empathy?

Regards,
	Alexey