netbsd man page for dtmfdecode

DTMFDECODE(1)						    BSD General Commands Manual 					     DTMFDECODE(1)

NAME
     dtmfdecode -- decodes DTMF tones from A-law audio data

SYNOPSIS
     dtmfdecode

DESCRIPTION
     dtmfdecode is part of the isdn4bsd package and is used to detect DTMF tones in the audio stream.

     It reads audio G.711 A-law coded data from stdin and outputs the detected numbers values as ASCII characters to stdout.

     The detector is implemented as 8 narrow band-pass filters realized with an integer double-cross recursive algorithm.  Various ad-hoc methods
     are employed to provide hysteresis and anti-bounce for the detected signals.

EXAMPLES
     The command:

	   dtmfdecode < beep.al

     will print a "1" to stdout.

STANDARDS
     ITU Recommendations G.711

AUTHORS
     The dtmfdecode utility was written by Poul-Henning Kamp <phk@freebsd.org>.  This man page was written by
     Hellmuth Michaelis <hm@freebsd.org>.

BSD
								 February 15, 1999							       BSD