NAME

       dahdi_monitor - checks the Rx/Tx levels of a DAHDI channels

SYNOPSIS

       dahdi_monitor  num  [-v[v]]  dahdi_monitor  num  [-o]  [<-f|-F>  FILE]  dahdi_monitor  num
       [[<-r|-R> FILE]] [[<-t|-T> FILE]]

DESCRIPTION

       dahdi_monitor monitors a Dahdi channel. It can record the output to a file, play it to the
       speaker, or visualize the audio levels on the terminal.

       Recorded  audio  files  are  by  default raw signed linear PCM. If the file name ends with
       ".wav", the recorded file will be a WAV file.

       The visual display shows the current audio  level  at  both  the  Rx  (audio  Received  by
       Asterisk) and Tx (audio Transmitted by Asterisk)

       To exit the program, press Ctrl-C.

OPTIONS

       The first (mandatory) parameter is the number of the channel to monitor.

       -m
              Multiple  channels.  Don't  multiplex both Rx and Tx in a single channel.  Normally
              there's a different option that you need that implies it.

       -o
              Plays the output to OSS (/dev/dsp). Requires -m not to be used.

       -v
              Display Visual audio levels. With two v-s, Verbose mode is enabled, that shows  the
              actual  levels as numbers. Note that this requires a terminal wider than 80 columns
              to be properly displayed.

              Implies -m.

       -f FILE
              Record the content of the channel (Tx + Rx) to a file.

       -F FILE
              Record the content of the channel (Tx + Rx) before the echo canceler to a file.

       -r FILE
              Record the content of the Rx channel to a file.

              Implies -m.

       -R FILE
              Record the content of the R channel before the echo canceler to a file.

              Implies -m.

       -s FILE
              Record the content of the Tx and Rx of the channel to a file.

       -S FILE
              Records a stereo of both Tx and Rx of the channel before the  echo  canceler  to  a
              file.

       -t FILE
              Record the content of the Tx channel to a file.

              Implies -m.

       -T FILE
              Record the content of the Tx channel before the echo canceler to a file.

              Implies -m.

EXAMPLES

       Visualize audio levels on DAHDI channel 2:

         dahdi_monitor 2 -v

       Record channel 3 to a file:

         dahdi_monitor 3 -f output.raw

       This  will create a raw PCM file (signed-linear, 8kHz, mono, 16 bits per sample). Both the
       Tx and Rx will be multiplexed in a single channel.  It can be  converted  to  a  WAV  file
       using e.g.:

         sox -s -c1 -2 -r8000 output.raw output.wav

       Record Tx and Rx of channel 5 to separate files. This time directly to WAV files:

         dahdi_monitor 5 -r output_rx.wav -t output_tx.wav

       Record channel 8 to a stereo file (Tx and Rx on its two channels):

         dahdi_monitor 8 -s output.raw

       Converting it to a WAV file:

         sox -s -c2 -2 -r8000 output.raw output.wav

SEE ALSO

       dahdi_tool(8), dahdi_cfg(8).

AUTHOR

       This  manual  page was written by Santiago Ruano Rincón <santiago@unicauca.edu.co> for the
       Debian system (but may be used by others).  Permission  is  granted  to  copy,  distribute
       and/or  modify  this document under the terms of the GNU General Public License, Version 2
       any later version published by the Free Software Foundation.

                                            9 Sep 2011                           DAHDI_MONITOR(8)