New functionality in ISDN4BSD

[Hans Petter Selasky]

Hi all!

I've just added some new interesting functionality to my I4B, and that is the 
possibility to dump the echo cancel FIR filter during live conversations.

Information on how to do the dump is described in "man isdnconfig". 
See "dump_ec".

For example you can make a script like this:

#!/bin/sh
while true
do
isdnconfig -u 63 -c 1 dump_ec
sleep 1
done

And then pipe the output to "octave" or "matlab" for example:

./live_trace.sh | octave

Here is a snapshot:

http://www.turbocat.net/~hselasky/isdn4bsd/echo_cancel_live.png

The FIR filter reveals very much information about the characteristics of the 
phone line. In the snapshot above you will see two peaks, hence two speakers 
are involved.

Have fun!

--HPS

http://www.turbocat.net/~hselasky/isdn4bsd