ca4ti/speak.pl

## speak.pl
#!/usr/bin/perl

#--------------------------------------------------
# Usage:
# ./speak.pl en input.txt output.mp3
#
# Prerequisites:
# sudo apt-get install libwww-perl libhtml-tree-perl sox libsox-fmt-mp3
#
# Compiling sox:
# Older versions of sox package might not have the support for mp3 codec,
# so just download sox from http://sox.sourceforge.net/
# install packages libmp3lame-dev libmad0-dev
# and compile sox
#
# List of language code names for Google TTS:
#	af	Afrikaans
#	sq	Albanian
#	am	Amharic
#	ar	Arabic
#	hy	Armenian
#	az	Azerbaijani
#	eu	Basque
#	be	Belarusian
#	bn	Bengali
#	bh	Bihari
#	bs	Bosnian
#	br	Breton
#	bg	Bulgarian
#	km	Cambodian
#	ca	Catalan
#	zh-CN	Chinese (Simplified)
#	zh-TW	Chinese (Traditional)
#	co	Corsican
#	hr	Croatian
#	cs	Czech
#	da	Danish
#	nl	Dutch
#	en	English
#	eo	Esperanto
#	et	Estonian
#	fo	Faroese
#	tl	Filipino
#	fi	Finnish
#	fr	French
#	fy	Frisian
#	gl	Galician
#	ka	Georgian
#	de	German
#	el	Greek
#	gn	Guarani
#	gu	Gujarati
#	ha	Hausa
#	iw	Hebrew
#	hi	Hindi
#	hu	Hungarian
#	is	Icelandic
#	id	Indonesian
#	ia	Interlingua
#	ga	Irish
#	it	Italian
#	ja	Japanese
#	jw	Javanese
#	kn	Kannada
#	kk	Kazakh
#	rw	Kinyarwanda
#	rn	Kirundi
#	ko	Korean
#	ku	Kurdish
#	ky	Kyrgyz
#	lo	Laothian
#	la	Latin
#	lv	Latvian
#	ln	Lingala
#	lt	Lithuanian
#	mk	Macedonian
#	mg	Malagasy
#	ms	Malay
#	ml	Malayalam
#	mt	Maltese
#	mi	Maori
#	mr	Marathi
#	mo	Moldavian
#	mn	Mongolian
#	sr-ME	Montenegrin
#	ne	Nepali
#	no	Norwegian
#	nn	Norwegian (Nynorsk)
#	oc	Occitan
#	or	Oriya
#	om	Oromo
#	ps	Pashto
#	fa	Persian
#	pl	Polish
#	pt-BR	Portuguese (Brazil)
#	pt-PT	Portuguese (Portugal)
#	pa	Punjabi
#	qu	Quechua
#	ro	Romanian
#	rm	Romansh
#	ru	Russian
#	gd	Scots Gaelic
#	sr	Serbian
#	sh	Serbo-Croatian
#	st	Sesotho
#	sn	Shona
#	sd	Sindhi
#	si	Sinhalese
#	sk	Slovak
#	sl	Slovenian
#	so	Somali
#	es	Spanish
#	su	Sundanese
#	sw	Swahili
#	sv	Swedish
#	tg	Tajik
#	ta	Tamil
#	tt	Tatar
#	te	Telugu
#	th	Thai
#	ti	Tigrinya
#	to	Tonga
#	tr	Turkish
#	tk	Turkmen
#	tw	Twi
#	ug	Uighur
#	uk	Ukrainian
#	ur	Urdu
#	uz	Uzbek
#	vi	Vietnamese
#	cy	Welsh
#	xh	Xhosa
#	yi	Yiddish
#	yo	Yoruba
#	zu	Zulu
#--------------------------------------------------

use strict;

use HTTP::Cookies;
use WWW::Mechanize;
use LWP;
use HTML::TreeBuilder;
use Data::Dumper;
$Data::Dumper::Maxdepth = 2;

if (scalar(@ARGV) != 3) {
	print STDERR "Usage: $0 LANGUAGE IN.txt OUT.mp3\n";
	print STDERR "\n";
	print STDERR "Examples: \n";
	print STDERR "    echo \"Hello world\" | ./speak.pl en speech.mp3\n";
	print STDERR "    cat file.txt       | ./speak.pl en speech.mp3\n";
	exit;
}

my $language = $ARGV[0]; # sk | en | cs | ...
my $textfile_in = $ARGV[1];
my $all_mp3_out = $ARGV[2];

my $SENTENCE_MAX_CHARACTERS = 100; # limit for google tts
my $TMP_DIR = "$all_mp3_out.tmp";
my $RECAPTCHA_URL = "http://www.google.com/sorry/?continue=http%3A%2F%2Ftranslate.google.com%2Ftranslate_tts%3Ftl=en%26q=Your+identity+was+successfuly+confirmed.";
my $RECAPTCHA_SLEEP_SECONDS = 60;
my $SYSTEM_WEBBROWSER = "firefox";
my $MAX_OPENED_FILES = 1000;
mkdir $TMP_DIR;

my $silence_duration_paragraphs = 0.8;
my $silence_duration_sentences  = 0.2;
my $silence_duration_comma      = 0.1;
my $silence_duration_brace      = 0.1;
my $silence_duration_semicolon  = 0.2;
my $silence_duration_words      = 0.05;

my @headers = (
'Host' => 'translate.google.com',
'User-Agent' => 'Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.5) Gecko/20091109 Ubuntu/9.10 (karmic) Firefox/3.5.5',
'Accept' => 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
'Accept-Language' => 'en-us,en;q=0.5',
'Accept-Encoding' => 'gzip,deflate',
'Accept-Charset' => 'ISO-8859-1,utf-8;q=0.7,*;q=0.7',
'Keep-Alive' => '300',
'Connection' => 'keep-alive',
);

my $cookie_jar = HTTP::Cookies->new(hide_cookie2 => 1);
#$cookie_jar->clear();
#$cookie_jar->set_cookie(undef, "SESSIONID", $sessionid, "/", $domain, undef, 1, 0, undef, 1);

my $mech = WWW::Mechanize->new(autocheck => 0, cookie_jar => $cookie_jar);
$mech->agent_alias( 'Windows IE 6' );
$mech->add_header( "Connection" => "keep-alive" );
$mech->add_header( "Accept" => "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8");
$mech->add_header( "Accept-Language" => "sk,cs;q=0.8,en-us;q=0.5,en;q=0.3");

my $browser = LWP::UserAgent->new;

my $referer = "";

my @all_mp3s = ();
my $sentence_idx = 0;
my $tts_requests_counter = 0;
my $sample_rate = 0;
# For each input line
open(IN, $textfile_in) or die("ERROR: Can not open file '$textfile_in'");
while (my $line = <IN>)
{
	chomp($line);
	print "line: $line\n";
	# Check for empty lines - paragraphs separator
	if ($line =~ /^\s*$/) {
		if ($sample_rate != 0) {
			push @all_mp3s, SilenceToMp3($sentence_idx++, $silence_duration_paragraphs, $sample_rate);
		}
	} else {
		my @words = split(/\s+/, $line);
		my $sentence = "";
		# For each word
		for (my $i=0; $i<scalar(@words); $i++)
		{
			my $word = $words[$i];
			$sentence .= " $word"; # add another word to the sentence
			my $say = 0;
			my $silence_duration = 0.0;
			if (length($sentence) >= $SENTENCE_MAX_CHARACTERS) {
				# Remove the last word;
				$sentence = substr($sentence, 0, length($sentence)-length($word)-1);
				$say = 1;
				$silence_duration = $silence_duration_words;
				$i --; # one word back
			}
			# If a separator was found
			elsif (substr($word, length($word)-1, 1) =~ /[.!?]/ ) {
				$say = 1;
				$silence_duration = $silence_duration_sentences;
			}
			elsif (substr($word, length($word)-1, 1) eq ",") {
				$say = 1;
				$silence_duration = $silence_duration_comma;
			}
			elsif (substr($word, length($word)-1, 1) eq ";") {
				$say = 1;
				$silence_duration = $silence_duration_semicolon;
			}
			elsif (substr($word, length($word)-1, 1) eq ")") {
				$say = 1;
				$silence_duration = $silence_duration_brace;
			}
			# If there are no more words
			elsif ($i == scalar(@words)-1) {
				$say = 1;
				$silence_duration = $silence_duration_words;
			}

			if ($say) {
				print "sentence[$tts_requests_counter]: $sentence\n";
				my $trimmed_mp3 = TrimSilence( SentenceToMp3($sentence, $sentence_idx++) );
				my $trimmed_mp3_sample_rate = `soxi -r $trimmed_mp3`;
				chomp($trimmed_mp3_sample_rate);
				if ($sample_rate == 0) {
					$sample_rate = $trimmed_mp3_sample_rate;
				}
				if ($sample_rate != $trimmed_mp3_sample_rate) {
					die("Error: sample rate of '$trimmed_mp3' differs from the sample rate of previous files.");
				}
				#print "trimmed_mp3_sample_rate: $trimmed_mp3_sample_rate\n";
				push @all_mp3s, $trimmed_mp3;
				push @all_mp3s, SilenceToMp3($sentence_idx++, $silence_duration, $sample_rate);
				$tts_requests_counter ++;
				$sentence = ""; # start a new sentence
			}
		}
	}
}

print "Concatenate: @all_mp3s\n";
print "Writing output to $all_mp3_out...";
JoinMp3s(\@all_mp3s, $all_mp3_out);
print "done\n";

sub JoinMp3s() {
	my $mp3s_ref = shift;
	my $mp3_out = shift;
	my $depth = shift || 0;

#	print "JoinMp3s(".join(" ",@{$mp3s_ref}).", $mp3_out, $depth)\n";

	#--------------------------------------------------
	# Problem if the number of mp3s exceeds the max number of opened files per process
	# The audio files should be concatenated by smaller chunks
	#--------------------------------------------------
	if (scalar(@{$mp3s_ref}) < $MAX_OPENED_FILES) {
		Exec("sox @{$mp3s_ref} $mp3_out");
	} else {
		my @subset_mp3s_out = ();
		my @subset_mp3s = ();
		my $sub_idx = 0;
		for (my $i = 0; $i < scalar(@{$mp3s_ref}); $i++) {
			push (@subset_mp3s, $mp3s_ref->[$i]);
			if (scalar(@subset_mp3s) >= $MAX_OPENED_FILES-1 || $i == scalar(@{$mp3s_ref})-1) {
				my $sub_mp3_out = "$TMP_DIR/subjoin_".$depth."_$sub_idx.mp3"; $sub_idx++;
				JoinMp3s(\@subset_mp3s, $sub_mp3_out, $depth+1);
				push (@subset_mp3s_out, $sub_mp3_out);
				@subset_mp3s = ();
			}
		}
		JoinMp3s(\@subset_mp3s_out, $mp3_out, $depth+1);
	}
}

sub SilenceToMp3() {
	my $idx = shift;
	my $duration = shift;
	my $sample_rate = shift;

	my $mp3_out = sprintf("$TMP_DIR/%04d_sil.mp3", $sentence_idx);
	Exec("sox -n -r $sample_rate $mp3_out trim 0.0 $duration");
	return $mp3_out;
}

sub SentenceToMp3() {
	my $sentence     = shift;
	my $sentence_idx = shift;

	$sentence =~ s/ /+/g;
	if (length($sentence) > $SENTENCE_MAX_CHARACTERS) {
		die ("ERROR: sentence has more than $SENTENCE_MAX_CHARACTERS characters: '$sentence'");
	}

	my $mp3_out = sprintf("$TMP_DIR/%04d.mp3", $sentence_idx);
	#print "mp3_out: $mp3_out\n";
	#print "http://translate.google.com/translate_tts?q=$sentence\n";

#	my $resp = GetSentenceResponse($sentence);
	my $resp = GetSentenceResponse_CaptchaAware($sentence); # NOT WORKING YET

	if (length($resp) == 0) {
		print "EMPTY SENTENCE: '$sentence'\n";
		return "";
	}
	open(FILE,">$mp3_out");
	print FILE $resp;
	close(FILE);
	return $mp3_out;
}

sub GetSentenceResponse() {
	my $sentence = shift;
	#my $resp = $browser->get("http://translate.google.com/translate_tts?tl=$language&q=$sentence", @headers);
	my $resp = $browser->get("http://translate.google.com/translate_tts?tl=$language&q=$sentence");

	if ($resp->content =~ "^<!DOCTYPE" ||
		$resp->content =~ "^<html>")
	{
		die("ERROR: expecting MP3 data, but got a HTML page!");
	}
	return $resp->content;
}

sub GetSentenceResponse_CaptchaAware() {
	my $sentence = shift;

	my $recaptcha_waiting = 0;
	print "URL: http://translate.google.com/translate_tts?tl=$language&q=$sentence\n";
	while (1) {
		#$resp = $browser->get("http://translate.google.com/translate_tts?tl=$language&q=$sentence", @headers);
		#print $resp->content;
		#$mech->get("http://translate.google.com/translate_tts?tl=$language&q=$sentence", @headers);
		my $url = "http://translate.google.com/translate_tts?tl=$language&q=$sentence";
		$mech->get($url); $mech->add_header( Referer => "$referer" ); $referer = $url;
#		print "Headers:\n".Dumper($mech->dump_headers());
#		open my $fh, '<', "recaptcha_response.html" or die "error opening file: $!";
#		$resp = do { local $/; <$fh> };
		if ($mech->response()->content() =~ /^<!DOCTYPE/ ||
			$mech->response()->content() =~ /^<html>/)
		{
			my $tree = HTML::TreeBuilder->new();
			$tree->parse_content($mech->response()->content());
			print "HTML response: ".$tree->as_text()."\n";

			if (!$recaptcha_waiting) {
				$recaptcha_waiting = 1;
				print "We have to wait\n";
			}
			print ".";
			sleep($RECAPTCHA_SLEEP_SECONDS);
			next;

			my $captcha_img_url = "http://translate.google.com".$tree->look_down("_tag", "img")->attr("src");
			print "img: ".$captcha_img_url;
			my $mech2 = $mech->clone();
			$referer = "http://www.google.com/sorry/?continue=$url";
			$mech2->add_header( Referer => "$referer" );
			$mech2->get($captcha_img_url, ':content_file' => 'captcha.jpg');

#			print "\n\n".$mech->response()->content()."\n\n";

			print "enter captcha here: ";
			my $val = <STDIN>;
			print "val: $val\n";

			# TODO: THIS DOES NOT WORK! MAYBE WAITING FOR HALF AN HOUR WOULD BE BETTER
			$mech->add_header( Referer => "$referer" );
			my $res = $mech->submit_form(with_fields => {captcha => "$val"});
			print "response: ".$res->content."\n";
		} else {
#			print "MP3 response\n";
			last;
		}
		sleep($RECAPTCHA_SLEEP_SECONDS);
		PrintWaitingDot();
	}
	if ($recaptcha_waiting) { print "\n"; }
	return $mech->response()->content();
}

sub PrintWaitingDot() {
	select STDOUT;
	print ".";
	$|=1;
}

sub TrimSilence() {
	my $mp3 = shift;

	if ($mp3 eq "") {
		return "";
	}

	my $mp3_out = $mp3;
	$mp3_out =~ s/\.mp3$/_trim.mp3/;
	Exec("
	sox $mp3 -p silence 1 0.1 -60d \\
	| sox -p -p reverse \\
	| sox -p -p silence 1 0.1 -60d \\
	| sox -p $mp3_out reverse
	");
	return $mp3_out;
}

sub Exec() {
	my $cmd = shift;
#	print "exec $cmd\n";
	system $cmd;
	return;
}
	#!/usr/bin/perl

	#--------------------------------------------------
	# Usage:
	# ./speak.pl en input.txt output.mp3
	#
	# Prerequisites:
	# sudo apt-get install libwww-perl libhtml-tree-perl sox libsox-fmt-mp3
	#
	# Compiling sox:
	# Older versions of sox package might not have the support for mp3 codec,
	# so just download sox from http://sox.sourceforge.net/
	# install packages libmp3lame-dev libmad0-dev
	# and compile sox
	#
	# List of language code names for Google TTS:
	# af Afrikaans
	# sq Albanian
	# am Amharic
	# ar Arabic
	# hy Armenian
	# az Azerbaijani
	# eu Basque
	# be Belarusian
	# bn Bengali
	# bh Bihari
	# bs Bosnian
	# br Breton
	# bg Bulgarian
	# km Cambodian
	# ca Catalan
	# zh-CN Chinese (Simplified)
	# zh-TW Chinese (Traditional)
	# co Corsican
	# hr Croatian
	# cs Czech
	# da Danish
	# nl Dutch
	# en English
	# eo Esperanto
	# et Estonian
	# fo Faroese
	# tl Filipino
	# fi Finnish
	# fr French
	# fy Frisian
	# gl Galician
	# ka Georgian
	# de German
	# el Greek
	# gn Guarani
	# gu Gujarati
	# ha Hausa
	# iw Hebrew
	# hi Hindi
	# hu Hungarian
	# is Icelandic
	# id Indonesian
	# ia Interlingua
	# ga Irish
	# it Italian
	# ja Japanese
	# jw Javanese
	# kn Kannada
	# kk Kazakh
	# rw Kinyarwanda
	# rn Kirundi
	# ko Korean
	# ku Kurdish
	# ky Kyrgyz
	# lo Laothian
	# la Latin
	# lv Latvian
	# ln Lingala
	# lt Lithuanian
	# mk Macedonian
	# mg Malagasy
	# ms Malay
	# ml Malayalam
	# mt Maltese
	# mi Maori
	# mr Marathi
	# mo Moldavian
	# mn Mongolian
	# sr-ME Montenegrin
	# ne Nepali
	# no Norwegian
	# nn Norwegian (Nynorsk)
	# oc Occitan
	# or Oriya
	# om Oromo
	# ps Pashto
	# fa Persian
	# pl Polish
	# pt-BR Portuguese (Brazil)
	# pt-PT Portuguese (Portugal)
	# pa Punjabi
	# qu Quechua
	# ro Romanian
	# rm Romansh
	# ru Russian
	# gd Scots Gaelic
	# sr Serbian
	# sh Serbo-Croatian
	# st Sesotho
	# sn Shona
	# sd Sindhi
	# si Sinhalese
	# sk Slovak
	# sl Slovenian
	# so Somali
	# es Spanish
	# su Sundanese
	# sw Swahili
	# sv Swedish
	# tg Tajik
	# ta Tamil
	# tt Tatar
	# te Telugu
	# th Thai
	# ti Tigrinya
	# to Tonga
	# tr Turkish
	# tk Turkmen
	# tw Twi
	# ug Uighur
	# uk Ukrainian
	# ur Urdu
	# uz Uzbek
	# vi Vietnamese
	# cy Welsh
	# xh Xhosa
	# yi Yiddish
	# yo Yoruba
	# zu Zulu
	#--------------------------------------------------

	use strict;

	use HTTP::Cookies;
	use WWW::Mechanize;
	use LWP;
	use HTML::TreeBuilder;
	use Data::Dumper;
	$Data::Dumper::Maxdepth = 2;

	if (scalar(@ARGV) != 3) {
	print STDERR "Usage: $0 LANGUAGE IN.txt OUT.mp3\n";
	print STDERR "\n";
	print STDERR "Examples: \n";
	print STDERR " echo \"Hello world\" \| ./speak.pl en speech.mp3\n";
	print STDERR " cat file.txt \| ./speak.pl en speech.mp3\n";
	exit;
	}

	my $language = $ARGV[0]; # sk \| en \| cs \| ...
	my $textfile_in = $ARGV[1];
	my $all_mp3_out = $ARGV[2];

	my $SENTENCE_MAX_CHARACTERS = 100; # limit for google tts
	my $TMP_DIR = "$all_mp3_out.tmp";
	my $RECAPTCHA_URL = "http://www.google.com/sorry/?continue=http%3A%2F%2Ftranslate.google.com%2Ftranslate_tts%3Ftl=en%26q=Your+identity+was+successfuly+confirmed.";
	my $RECAPTCHA_SLEEP_SECONDS = 60;
	my $SYSTEM_WEBBROWSER = "firefox";
	my $MAX_OPENED_FILES = 1000;
	mkdir $TMP_DIR;

	my $silence_duration_paragraphs = 0.8;
	my $silence_duration_sentences = 0.2;
	my $silence_duration_comma = 0.1;
	my $silence_duration_brace = 0.1;
	my $silence_duration_semicolon = 0.2;
	my $silence_duration_words = 0.05;

	my @headers = (
	'Host' => 'translate.google.com',
	'User-Agent' => 'Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.5) Gecko/20091109 Ubuntu/9.10 (karmic) Firefox/3.5.5',
	'Accept' => 'text/html,application/xhtml+xml,application/xml;q=0.9,/;q=0.8',
	'Accept-Language' => 'en-us,en;q=0.5',
	'Accept-Encoding' => 'gzip,deflate',
	'Accept-Charset' => 'ISO-8859-1,utf-8;q=0.7,*;q=0.7',
	'Keep-Alive' => '300',
	'Connection' => 'keep-alive',
	);

	my $cookie_jar = HTTP::Cookies->new(hide_cookie2 => 1);
	#$cookie_jar->clear();
	#$cookie_jar->set_cookie(undef, "SESSIONID", $sessionid, "/", $domain, undef, 1, 0, undef, 1);

	my $mech = WWW::Mechanize->new(autocheck => 0, cookie_jar => $cookie_jar);
	$mech->agent_alias( 'Windows IE 6' );
	$mech->add_header( "Connection" => "keep-alive" );
	$mech->add_header( "Accept" => "text/html,application/xhtml+xml,application/xml;q=0.9,/;q=0.8");
	$mech->add_header( "Accept-Language" => "sk,cs;q=0.8,en-us;q=0.5,en;q=0.3");

	my $browser = LWP::UserAgent->new;

	my $referer = "";

	my @all_mp3s = ();
	my $sentence_idx = 0;
	my $tts_requests_counter = 0;
	my $sample_rate = 0;
	# For each input line
	open(IN, $textfile_in) or die("ERROR: Can not open file '$textfile_in'");
	while (my $line = <IN>)
	{
	chomp($line);
	print "line: $line\n";
	# Check for empty lines - paragraphs separator
	if ($line =~ /^\s*$/) {
	if ($sample_rate != 0) {
	push @all_mp3s, SilenceToMp3($sentence_idx++, $silence_duration_paragraphs, $sample_rate);
	}
	} else {
	my @words = split(/\s+/, $line);
	my $sentence = "";
	# For each word
	for (my $i=0; $i<scalar(@words); $i++)
	{
	my $word = $words[$i];
	$sentence .= " $word"; # add another word to the sentence
	my $say = 0;
	my $silence_duration = 0.0;
	if (length($sentence) >= $SENTENCE_MAX_CHARACTERS) {
	# Remove the last word;
	$sentence = substr($sentence, 0, length($sentence)-length($word)-1);
	$say = 1;
	$silence_duration = $silence_duration_words;
	$i --; # one word back
	}
	# If a separator was found
	elsif (substr($word, length($word)-1, 1) =~ /[.!?]/ ) {
	$say = 1;
	$silence_duration = $silence_duration_sentences;
	}
	elsif (substr($word, length($word)-1, 1) eq ",") {
	$say = 1;
	$silence_duration = $silence_duration_comma;
	}
	elsif (substr($word, length($word)-1, 1) eq ";") {
	$say = 1;
	$silence_duration = $silence_duration_semicolon;
	}
	elsif (substr($word, length($word)-1, 1) eq ")") {
	$say = 1;
	$silence_duration = $silence_duration_brace;
	}
	# If there are no more words
	elsif ($i == scalar(@words)-1) {
	$say = 1;
	$silence_duration = $silence_duration_words;
	}

	if ($say) {
	print "sentence[$tts_requests_counter]: $sentence\n";
	my $trimmed_mp3 = TrimSilence( SentenceToMp3($sentence, $sentence_idx++) );
	my $trimmed_mp3_sample_rate = `soxi -r $trimmed_mp3`;
	chomp($trimmed_mp3_sample_rate);
	if ($sample_rate == 0) {
	$sample_rate = $trimmed_mp3_sample_rate;
	}
	if ($sample_rate != $trimmed_mp3_sample_rate) {
	die("Error: sample rate of '$trimmed_mp3' differs from the sample rate of previous files.");
	}
	#print "trimmed_mp3_sample_rate: $trimmed_mp3_sample_rate\n";
	push @all_mp3s, $trimmed_mp3;
	push @all_mp3s, SilenceToMp3($sentence_idx++, $silence_duration, $sample_rate);
	$tts_requests_counter ++;
	$sentence = ""; # start a new sentence
	}
	}
	}
	}

	print "Concatenate: @all_mp3s\n";
	print "Writing output to $all_mp3_out...";
	JoinMp3s(\@all_mp3s, $all_mp3_out);
	print "done\n";

	sub JoinMp3s() {
	my $mp3s_ref = shift;
	my $mp3_out = shift;
	my $depth = shift \|\| 0;

	# print "JoinMp3s(".join(" ",@{$mp3s_ref}).", $mp3_out, $depth)\n";

	#--------------------------------------------------
	# Problem if the number of mp3s exceeds the max number of opened files per process
	# The audio files should be concatenated by smaller chunks
	#--------------------------------------------------
	if (scalar(@{$mp3s_ref}) < $MAX_OPENED_FILES) {
	Exec("sox @{$mp3s_ref} $mp3_out");
	} else {
	my @subset_mp3s_out = ();
	my @subset_mp3s = ();
	my $sub_idx = 0;
	for (my $i = 0; $i < scalar(@{$mp3s_ref}); $i++) {
	push (@subset_mp3s, $mp3s_ref->[$i]);
	if (scalar(@subset_mp3s) >= $MAX_OPENED_FILES-1 \|\| $i == scalar(@{$mp3s_ref})-1) {
	my $sub_mp3_out = "$TMP_DIR/subjoin_".$depth."_$sub_idx.mp3"; $sub_idx++;
	JoinMp3s(\@subset_mp3s, $sub_mp3_out, $depth+1);
	push (@subset_mp3s_out, $sub_mp3_out);
	@subset_mp3s = ();
	}
	}
	JoinMp3s(\@subset_mp3s_out, $mp3_out, $depth+1);
	}
	}

	sub SilenceToMp3() {
	my $idx = shift;
	my $duration = shift;
	my $sample_rate = shift;

	my $mp3_out = sprintf("$TMP_DIR/%04d_sil.mp3", $sentence_idx);
	Exec("sox -n -r $sample_rate $mp3_out trim 0.0 $duration");
	return $mp3_out;
	}

	sub SentenceToMp3() {
	my $sentence = shift;
	my $sentence_idx = shift;

	$sentence =~ s/ /+/g;
	if (length($sentence) > $SENTENCE_MAX_CHARACTERS) {
	die ("ERROR: sentence has more than $SENTENCE_MAX_CHARACTERS characters: '$sentence'");
	}

	my $mp3_out = sprintf("$TMP_DIR/%04d.mp3", $sentence_idx);
	#print "mp3_out: $mp3_out\n";
	#print "http://translate.google.com/translate_tts?q=$sentence\n";

	# my $resp = GetSentenceResponse($sentence);
	my $resp = GetSentenceResponse_CaptchaAware($sentence); # NOT WORKING YET

	if (length($resp) == 0) {
	print "EMPTY SENTENCE: '$sentence'\n";
	return "";
	}
	open(FILE,">$mp3_out");
	print FILE $resp;
	close(FILE);
	return $mp3_out;
	}

	sub GetSentenceResponse() {
	my $sentence = shift;
	#my $resp = $browser->get("http://translate.google.com/translate_tts?tl=$language&q=$sentence", @headers);
	my $resp = $browser->get("http://translate.google.com/translate_tts?tl=$language&q=$sentence");

	if ($resp->content =~ "^<!DOCTYPE" \|\|
	$resp->content =~ "^<html>")
	{
	die("ERROR: expecting MP3 data, but got a HTML page!");
	}
	return $resp->content;
	}

	sub GetSentenceResponse_CaptchaAware() {
	my $sentence = shift;

	my $recaptcha_waiting = 0;
	print "URL: http://translate.google.com/translate_tts?tl=$language&q=$sentence\n";
	while (1) {
	#$resp = $browser->get("http://translate.google.com/translate_tts?tl=$language&q=$sentence", @headers);
	#print $resp->content;
	#$mech->get("http://translate.google.com/translate_tts?tl=$language&q=$sentence", @headers);
	my $url = "http://translate.google.com/translate_tts?tl=$language&q=$sentence";
	$mech->get($url); $mech->add_header( Referer => "$referer" ); $referer = $url;
	# print "Headers:\n".Dumper($mech->dump_headers());
	# open my $fh, '<', "recaptcha_response.html" or die "error opening file: $!";
	# $resp = do { local $/; <$fh> };
	if ($mech->response()->content() =~ /^<!DOCTYPE/ \|\|
	$mech->response()->content() =~ /^<html>/)
	{
	my $tree = HTML::TreeBuilder->new();
	$tree->parse_content($mech->response()->content());
	print "HTML response: ".$tree->as_text()."\n";

	if (!$recaptcha_waiting) {
	$recaptcha_waiting = 1;
	print "We have to wait\n";
	}
	print ".";
	sleep($RECAPTCHA_SLEEP_SECONDS);
	next;

	my $captcha_img_url = "http://translate.google.com".$tree->look_down("_tag", "img")->attr("src");
	print "img: ".$captcha_img_url;
	my $mech2 = $mech->clone();
	$referer = "http://www.google.com/sorry/?continue=$url";
	$mech2->add_header( Referer => "$referer" );
	$mech2->get($captcha_img_url, ':content_file' => 'captcha.jpg');

	# print "\n\n".$mech->response()->content()."\n\n";

	print "enter captcha here: ";
	my $val = <STDIN>;
	print "val: $val\n";

	# TODO: THIS DOES NOT WORK! MAYBE WAITING FOR HALF AN HOUR WOULD BE BETTER
	$mech->add_header( Referer => "$referer" );
	my $res = $mech->submit_form(with_fields => {captcha => "$val"});
	print "response: ".$res->content."\n";
	} else {
	# print "MP3 response\n";
	last;
	}
	sleep($RECAPTCHA_SLEEP_SECONDS);
	PrintWaitingDot();
	}
	if ($recaptcha_waiting) { print "\n"; }
	return $mech->response()->content();
	}

	sub PrintWaitingDot() {
	select STDOUT;
	print ".";
	$\|=1;
	}

	sub TrimSilence() {
	my $mp3 = shift;

	if ($mp3 eq "") {
	return "";
	}

	my $mp3_out = $mp3;
	$mp3_out =~ s/\.mp3$/_trim.mp3/;
	Exec("
	sox $mp3 -p silence 1 0.1 -60d \\
	\| sox -p -p reverse \\
	\| sox -p -p silence 1 0.1 -60d \\
	\| sox -p $mp3_out reverse
	");
	return $mp3_out;
	}

	sub Exec() {
	my $cmd = shift;
	# print "exec $cmd\n";
	system $cmd;
	return;
	}