Getting voice events while recording

[jdaniels]

Hi,

I have a Redhat machine which dials up to a Dynamode voice modem from a series of shell scripts included with the Big Brother monitoring app. The situation is this: I can dial out to a given number, and I am looking at one of two scenarios occurring; 1) the call goes in the normal way and terminates when the modem returns a 'SILENCE_DETECTED' event; 2) The call dials to a non-existent number, gets the universal "I'm sorry, this number is not in use" three-tone message. In both of the above, I am recording the call. However I want to monitor the file size of the recorded call because when I dial the dead line number, the modem never hangs up, so I aim to either kill the process or send the modem a STOP and GOODBYE sequence of commands when the file reaches a certain size. Both these approaches work ... but not at the same time. The script extract I am using goes like this:

send "RECORD $FILENAME"

ANSWER=`receive`

while true; do
ANSWER=`receive` # ref1
case $ANSWER in
RECORDING) # code to monitor file size
SILENCE_DETECTED) # doce to terminate on silence
esac
done

The problem is at the line marked 'ref1' - if that line is present, I can detect SILENCE_DETECTED modem responses. However I cannot stay in the RECORDING state. Conversely if I delete that line, I can stay in the recording state and monitor the file size, but cannot detect silences. For some reason our modem does not respond to BUSY_TONE signals, hence this workaround. does anyone have any ideas on this?

Thanks,

Jon Daniels

 

[pansophic]

The best way to solve this problem is to use a CTI card like Dialogic, Natural Microsystems or Brooktrout. They actually have reasonable call progress tone detection, which modems do not.

The downside is that they cost a lot more than a modem.

Most modems will only properly detect call progress tones a small percentage of the time. And their ability to detect events other than busy and dialtone are EXTREMELY limited.

Sorry that I can't offer a solution that makes your modem work.


pansophic

 

[jdaniels]

Thanks for your input. I think what I will do is this: at the same time as I run the call script, I will run a monitoring script that kills the record process when the file reaches a certain size. As you say, it seems to be working some of the time, but not every time ...

Thanks again
Jon