Removed sox related code.

Sox is no longer an option for sound conversion.
Tests failed to show any improvements in detection rates when
sox is used for normalising sound data.

README

@@ -17,9 +17,6 @@ Internet access in order to contact google and get the speech data.
 If you plan to use SSL you will need to install the 'IO-Socket-SSL' Perl module
 that implements an interface to SSL sockets.
 
-The script can optionally use sox for sound conversion. It works with recent
-versions of sox (It will not work in RHEL/Centos 5).
-
 ------------
 Installation
 ------------
@@ -52,15 +49,15 @@ sample dialplan code for your extensions.conf
 ;Simple speech recognition
 exten => 1234,1,Answer()
 exten => 1234,n,agi(speech-recog.agi,en-US)
-exten => 1234,n,Noop(== The text you just said is: ${utterance} ==)
-exten => 1234,n,Noop(== The probability to be right is: ${confidence} ==)
+exten => 1234,n,Verbose(1,The text you just said is: ${utterance})
+exten => 1234,n,Verbose(1,The probability to be right is: ${confidence})
 exten => 1234,n,Hangup()
 
 ;Speech recognition demo also using googletts.agi for text to speech synthesis:
 exten => 1235,1,Answer()
 exten => 1235,n,agi(googletts.agi,"Say something in English, when done press the pound key.",en)
 exten => 1235,n(record),agi(speech-recog.agi,en-US)
-exten => 1235,n,Noop(= Script returned: ${status} , ${id} , ${confidence} , ${utterance} =)
+exten => 1235,n,Verbose(1,Script returned: ${status} , ${id} , ${confidence} , ${utterance})
 
 ;Check return status:
 exten => 1235,n,GotoIf($["${status}" = "0"]?success:fail)

speech-recog.agi

@@ -33,8 +33,6 @@
 # Default language:  $language
 # Sample rate:       $samplerate (value in Hz, 8000 or 16000 if used with wideband codecs)
 # SSL:               $use_ssl (0: disable, 1: enable)
-# Enable sox:        $use_sox (0: disable, 1: enable)
-# Normalizing level: $gain (value in db, applicable only if sox is enabled)
 #
 
 use warnings;
@@ -55,12 +53,6 @@ my $samplerate = 8000;
 # Use SSL                       #
 my $use_ssl = 0;
 
-# Use sox for sound encoding    #
-my $use_sox = 0;
-
-# Max sound power gain in dB    #
-my $gain = -5;
-
 # Verbose debugging messages    #
 my $debug = 0;
 
@@ -86,7 +78,6 @@ my $timeout    = 10000;
 my $tmpdir     = "/tmp";
 my $filetype   = "x-flac";
 my $host       = "www.google.com/speech-api/v1/recognize?xjerr=1&client=chromium";
-my $sox        = `/usr/bin/which sox`;
 my $flac       = `/usr/bin/which flac`;
 
 # Check endianness #
@@ -107,11 +98,10 @@ while (<STDIN>) {
 $name = " -- $AGI{request}:";
 
 # Abort if required programs not found. #
-die "$name sox is missing. Aborting.\n" if (!$sox && $use_sox);
-die "$name flac is missing. Aborting.\n" if (!$flac && !$use_sox);
+die "$name flac is missing. Aborting.\n" if (!$flac);
 
-chomp($sox, $flac);
-print STDERR "$name Found sox in: $sox, flac in: $flac\n" if ($debug);
+chomp($flac);
+print STDERR "$name Found flac in: $flac\n" if ($debug);
 
 # Setting recording file format according to sample rate. #
 if ($samplerate == 16000) {
@@ -183,19 +173,10 @@ if ($debug) {
 }
 
 # Encode file to flac. #
-if ($use_sox) {
-	# Covert file using sox, normalizing to -5db and removing possible DC offset. #
-	system($sox, "-b", "16", "-t", "raw", "-r", $samplerate, "-e", "signed-integer",
-		"--endian", $endian, "$tmpname.$format", "$tmpname.flac", "norm", $gain,
-		"highpass", "10") == 0
-		or die "$name $sox failed: $?\n";
-} else {
-	# Convert sound file using flac. #
-	system($flac, $comp_level, "--totally-silent", "--channels=1", "--endian=$endian",
-		"--sign=signed", "--bps=16", "--force-raw-format", "--sample-rate=$samplerate",
-		"$tmpname.$format") == 0
-		or die "$name $flac failed: $?\n";
-}
+system($flac, $comp_level, "--totally-silent", "--channels=1", "--endian=$endian",
+	"--sign=signed", "--bps=16", "--force-raw-format", "--sample-rate=$samplerate",
+	"$tmpname.$format") == 0
+	or die "$name $flac failed: $?\n";
 
 open($fh, "<", "$tmpname.flac") or die "Can't read file: $!";
 $audio = do { local $/; <$fh> };