Can run from external directory. Outputs CSV. Works with TextGrids.

__init__.py

@@ -0,0 +1 @@
+__author__ = 'jkeshet'

extract_features.py

@@ -277,3 +277,19 @@ def create_features(input_wav_filename, feature_filename, begin=None, end=None,
     np.savetxt(feature_filename, np.asarray(arcep_mat), delimiter=",", fmt="%s")
     return arcep_mat
 
+
+if __name__ == "__main__":
+    # parse arguments
+    parser = argparse.ArgumentParser(description='Extract features for formants estimation.')
+    parser.add_argument('wav_file', default='', help="WAV audio filename (single vowel or an whole utternace)")
+    parser.add_argument('feature_file', default='', help="output feature text file")
+    parser.add_argument('--begin', help="beginning time in the WAV file", default=0.0, type=float)
+    parser.add_argument('--end', help="end time in the WAV file", default=-1.0, type=float)
+    args = parser.parse_args()
+
+    if args.begin > 0.0 or args.end > 0.0:
+        create_features(args.wav_file, args.feature_file, args.begin, args.end)
+    else:
+        create_features(args.wav_file, args.feature_file)
+
+

formants.py

@@ -1,25 +1,11 @@
 
 import extract_features as features
-from subprocess import call
-import sys
 import argparse
-import tempfile
+from helpers.textgrid import *
+from helpers.utilities import *
+import shutil
 
-
+def predict_from_times(wav_filename, preds_filename, begin, end):
-def easy_call(command, debug_mode=True):
-    try:
-        if debug_mode:
-            print >>sys.stderr, command
-        call(command, shell=True)
-    except Exception as exception:
-        print "Error: could not execute the following"
-        print ">>", command
-        print type(exception)     # the exception instance
-        print exception.args      # arguments stored in .args
-        exit(-1)
-
-
-def main(wav_filename, preds_filename, begin, end):
     tmp_features_filename = tempfile._get_default_tempdir() + "/" + next(tempfile._get_candidate_names()) + ".txt"
     print tmp_features_filename
 
@@ -31,14 +17,53 @@ def main(wav_filename, preds_filename, begin, end):
         easy_call("th load_tracking_model.lua " + tmp_features_filename + ' ' + preds_filename)
 
 
+def predict_from_textgrid(wav_filename, preds_filename, textgrid_filename, textgrid_tier):
+
+    print wav_filename
+
+    if os.path.exists(preds_filename):
+        os.remove(preds_filename)
+
+    textgrid = TextGrid()
+
+    # read TextGrid
+    textgrid.read(textgrid_filename)
+
+    # extract tier names
+    tier_names = textgrid.tierNames()
+
+    if textgrid_tier in tier_names:
+        tier_index = tier_names.index(textgrid_tier)
+        # run over all intervals in the tier
+        for interval in textgrid[tier_index]:
+            if re.search(r'\S', interval.mark()):
+                tmp_features_filename = generate_tmp_filename()
+                tmp_preds = generate_tmp_filename()
+                features.create_features(wav_filename, tmp_features_filename, interval.xmin(), interval.xmax())
+                easy_call("th load_estimation_model.lua " + tmp_features_filename + ' ' + tmp_preds)
+                csv_append_row(tmp_preds, preds_filename)
+    else:  # process first tier
+        for interval in textgrid[0]:
+            if re.search(r'\S', interval.mark()):
+                tmp_features_filename = generate_tmp_filename()
+                tmp_preds = generate_tmp_filename()
+                features.create_features(wav_filename, tmp_features_filename, interval.xmin(), interval.xmax())
+                easy_call("th load_estimation_model.lua " + tmp_features_filename + ' ' + tmp_preds)
+                csv_append_row(tmp_preds, preds_filename)
+
 if __name__ == "__main__":
     # parse arguments
-    parser = argparse.ArgumentParser(description='Extract features for formants estimation.')
+    parser = argparse.ArgumentParser(description='Estimation and tracking of formants.')
     parser.add_argument('wav_file', default='', help="WAV audio filename (single vowel or an whole utternace)")
-    parser.add_argument('formants_file', default='', help="output formant text file")
+    parser.add_argument('formants_file', default='', help="output formant CSV file")
+    parser.add_argument('--textgrid_filename', default='', help="get beginning and end times from a TextGrid file")
+    parser.add_argument('--textgrid_tier', default='', help="a tier name with portion to process (default first tier)")
     parser.add_argument('--begin', help="beginning time in the WAV file", default=0.0, type=float)
     parser.add_argument('--end', help="end time in the WAV file", default=-1.0, type=float)
     args = parser.parse_args()
 
-    main(args.wav_file, args.formants_file, args.begin, args.end)
+    if args.textgrid_filename:
+        predict_from_textgrid(args.wav_file, args.formants_file, args.textgrid_filename, args.textgrid_tier)
+    else:
+        predict_from_times(args.wav_file, args.formants_file, args.begin, args.end)
 

helpers/__init__.py

@@ -0,0 +1 @@
+__author__ = 'jkeshet'

helpers/textgrid.py

@@ -0,0 +1,413 @@
+# This file is a slightly modified version of the textgrid.py module
+# (https://github.com/kylebgorman/textgrid/), which was released under the following license:
+# (see https://github.com/kylebgorman/textgrid/blob/master/LICENSE)
+#
+# Copyright (c) 2011-2013 Kyle Gorman, Max Bane, Morgan Sonderegger
+#
+# Permission is hereby granted, free of charge, to any person obtaining a
+# copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be included
+# in all copies or substantial portions of the Software.
+
+
+
+import logging
+import re
+
+
+class mlf:
+    """
+    read in a HTK .mlf file. iterating over it gives you a list of 
+    TextGrids
+    """
+
+    def __init__(self, file):
+        self.__items = []
+        self.__n = 0
+        text = open(file, 'r')
+        text.readline() # get rid of header
+        while 1: # loop over text
+            name = text.readline()[1:-1]
+            if name:
+                grid = TextGrid()
+                phon = IntervalTier('phones')
+                word = IntervalTier('words')
+                wmrk = ''
+                wsrt = 0.
+                wend = 0.
+                while 1: # loop over the lines in each grid
+                    line = text.readline().rstrip().split()
+                    if len(line) == 4: # word on this baby
+                        pmin = float(line[0]) / 10e6
+                        pmax = float(line[1]) / 10e6
+                        phon.append(Interval(pmin, pmax, line[2]))
+                        if wmrk:
+                            word.append(Interval(wsrt, wend, wmrk))
+                        wmrk = line[3]
+                        wsrt = pmin
+                        wend = pmax
+                    elif len(line) == 3: # just phone
+                        pmin = float(line[0]) / 10e6
+                        pmax = float(line[1]) / 10e6
+                        phon.append(Interval(pmin, pmax, line[2]))
+                        wend = pmax 
+                    else: # it's a period
+                        word.append(Interval(wsrt, wend, wmrk))
+                        self.__items.append(grid)
+                        break
+                grid.append(phon)
+                grid.append(word)
+                self.__n += 1
+            else:
+                text.close()
+                break
+
+    def __iter__(self):
+        return iter(self.__items)
+
+    def __len__(self):
+        return self.__n
+
+    def __str__(self):
+        return '<MLF instance with %d TextGrids>' % self.__n
+
+class TextGrid:
+    """ represents Praat TextGrids as list of different types of tiers """
+
+    def __init__(self, name = None): 
+        self.__tiers = []
+        self.__n = 0
+        self.__xmin = None
+        self.__xmax = None
+        self.__name = name # this is just for the MLF case
+
+    def __str__(self):
+        return '<TextGrid with %d tiers>' % self.__n
+
+    def __iter__(self):
+        return iter(self.__tiers)
+
+    def __len__(self):
+        return self.__n
+
+    def __getitem__(self, i):
+        """ return the (i-1)th tier """
+        return self.__tiers[i] 
+
+    # Morgan Sonderegger
+    def tierNames(self, case=None):
+        names = [t.name() for t in self.__tiers]
+        if(case=="lower"):
+            names = [n.lower() for n in names]
+        return names
+
+    def xmin(self):
+        return self.__xmin
+
+    def xmax(self):
+        return self.__xmax
+
+    def append(self, tier):
+        self.__tiers.append(tier)
+        ## JosephKeshet
+        if self.__xmin is None:
+            self.__xmin = tier.xmin()
+        else:
+            self.__xmin = min(tier.xmin(), self.__xmin)
+        ## JosephKeshet
+        self.__xmax = max(tier.xmax(), self.__xmax)
+        ## JosephKeshet / MS
+        if self.__xmax is None:
+            self.__xmax = tier.xmax()
+        else:
+            self.__xmax = max(tier.xmax(), self.__xmax)
+        self.__n += 1
+
+    def read(self, file):
+        """ read TextGrid from Praat .TextGrid file """
+        text = open(file, 'r')
+        text.readline() # header crap
+        text.readline()
+        text.readline()
+        self.__xmin = float(text.readline().rstrip().split()[2])
+        self.__xmax = float(text.readline().rstrip().split()[2])
+        text.readline()
+        m = int(text.readline().rstrip().split()[2]) # will be self.__n soon
+        text.readline()
+        for i in range(m): # loop over grids
+            text.readline()
+            if text.readline().rstrip().split()[2] == '"IntervalTier"':
+                # inam = text.readline().rstrip().split()[2][1:-1]
+                inam = text.readline().split('=')[1].strip().strip('"') # Joseph Keshet: handle space in the tier name
+                imin = float(text.readline().rstrip().split()[2])
+                imax = float(text.readline().rstrip().split()[2])
+                itie = IntervalTier(inam, imin, imax) # redundant FIXME
+                n = int(text.readline().rstrip().split()[3])
+                for j in range(n):
+                    try:
+                        text.readline().rstrip().split() # header junk
+                        jmin = float(text.readline().rstrip().split()[2])
+                        jmax = float(text.readline().rstrip().split()[2])
+                        # Morgan Sonderegger changed, to account for intervals where label
+                        # begins with spacing
+                        #jmrk = text.readline().rstrip().split()[2][1:-1]
+                        #jmrk = text.readline().split('=')[1].strip().strip('"') # Joseph Keshet: handle space in the
+                        # tier
+                        # name
+                        jmrk = getMark(text)
+                        #
+                        itie.append(Interval(jmin, jmax, jmrk))
+                    except:
+                        logging.error("Unable to parse TextGrid %s." % text.name)
+
+                self.append(itie) 
+            else: # pointTier
+                # inam = text.readline().rstrip().split()[2][1:-1]
+                inam = text.readline().split('=')[1].strip().strip('"') # Joseph Keshet: handle space in the tier name
+                imin = float(text.readline().rstrip().split()[2])
+                imax = float(text.readline().rstrip().split()[2])
+                itie = PointTier(inam, imin, imax) # redundant FIXME
+                n = int(text.readline().rstrip().split()[3])
+                for j in range(n):
+                    text.readline().rstrip() # header junk
+                    jtim = float( text.readline().rstrip().split()[2])
+                    jmrk = text.readline().rstrip().split()[2][1:-1]
+                    itie.append(Point(jtim, jmrk))
+                self.append(itie)
+        text.close()
+
+    def write(self, text):
+        """ write it into a text file that Praat can read """
+        text = open(text, 'w')
+        text.write('File type = "ooTextFile"\n')
+        text.write('Object class = "TextGrid"\n\n')
+        text.write('xmin = %f\n' % self.__xmin)
+        text.write('xmax = %f\n' % self.__xmax)
+        text.write('tiers? <exists>\n')
+        text.write('size = %d\n' % self.__n)
+        text.write('item []:\n')
+        for (tier, n) in zip(self.__tiers, range(1, self.__n + 1)):
+            text.write('\titem [%d]:\n' % n)
+            if tier.__class__ == IntervalTier: 
+                text.write('\t\tclass = "IntervalTier"\n')
+                text.write('\t\tname = "%s"\n' % tier.name())
+                text.write('\t\txmin = %f\n' % tier.xmin())
+                text.write('\t\txmax = %f\n' % tier.xmax())
+                text.write('\t\tintervals: size = %d\n' % len(tier))
+                for (interval, o) in zip(tier, range(1, len(tier) + 1)): 
+                    text.write('\t\t\tintervals [%d]:\n' % o)
+                    text.write('\t\t\t\txmin = %f\n' % interval.xmin())
+                    text.write('\t\t\t\txmax = %f\n' % interval.xmax())
+                    text.write('\t\t\t\ttext = "%s"\n' % interval.mark())
+            else: # PointTier
+                text.write('\t\tclass = "TextTier"\n')
+                text.write('\t\tname = "%s"\n' % tier.name())
+                text.write('\t\txmin = %f\n' % tier.xmin())
+                text.write('\t\txmax = %f\n' % tier.xmax())
+                text.write('\t\tpoints: size = %d\n' % len(tier))
+                for (point, o) in zip(tier, range(1, len(tier) + 1)):
+                    text.write('\t\t\tpoints [%d]:\n' % o)
+                    text.write('\t\t\t\ttime = %f\n' % point.time())
+                    text.write('\t\t\t\tmark = "%s"\n' % point.mark())
+        text.close()
+
+class IntervalTier:
+    """ represents IntervalTier as a list plus some features: min/max time, 
+    size, and tier name """
+
+    def __init__(self, name = None, xmin = None, xmax = None):
+        self.__n = 0
+        self.__name = name
+        self.__xmin = xmin
+        self.__xmax = xmax
+        self.__intervals = []
+
+    def __str__(self):
+        return '<IntervalTier "%s" with %d points>' % (self.__name, self.__n)
+
+    def __iter__(self):
+        return iter(self.__intervals)
+
+    def __len__(self):
+        return self.__n
+
+    def __getitem__(self, i):
+        """ return the (i-1)th interval """
+        return self.__intervals[i]
+
+    def xmin(self):
+        return self.__xmin
+
+    def xmax(self):
+        return self.__xmax
+
+    def name(self):
+        return self.__name
+
+    def append(self, interval):
+        self.__intervals.append(interval)
+        self.__xmax = interval.xmax()
+        self.__n += 1
+
+    # Morgan Sonderegger added
+    def remove(self, interval):
+        logging.debug("removing %d" % interval.xmin())
+        self.__intervals.remove(interval)
+        self.__n -= 1
+
+    def read(self, file):
+        text = open(file, 'r')
+        text.readline() # header junk 
+        text.readline()
+        text.readline()
+        self.__xmin = float(text.readline().rstrip().split()[2])
+        self.__xmax = float(text.readline().rstrip().split()[2])
+        self.__n = int(text.readline().rstrip().split()[3])
+        for i in range(self.__n):
+            text.readline().rstrip() # header
+            imin = float(text.readline().rstrip().split()[2]) 
+            imax = float(text.readline().rstrip().split()[2])
+            # imrk = text.readline().rstrip().split()[2].replace('"', '') # txt
+            imrk = text.readline().split('=')[1].strip().strip('"') # Joseph Keshet: handle space in the mark
+            self.__intervals.append(Interval(imin, imax, imrk))
+        text.close()
+
+    def write(self, file):
+        text = open(file, 'w')
+        text.write('File type = "ooTextFile"\n')
+        text.write('Object class = "IntervalTier"\n\n')
+        text.write('xmin = %f\n' % self.__xmin)
+        text.write('xmax = %f\n' % self.__xmax)
+        text.write('intervals: size = %d\n' % self.__n)
+        for (interval, n) in zip(self.__intervals, range(1, self.__n + 1)):
+            text.write('intervals [%d]:\n' % n)
+            text.write('\txmin = %f\n' % interval.xmin())
+            text.write('\txmax = %f\n' % interval.xmax())
+            text.write('\ttext = "%s"\n' % interval.mark())
+        text.close()
+
+class PointTier:
+    """ represents PointTier (also called TextTier for some reason) as a list 
+    plus some features: min/max time, size, and tier name """
+
+    def __init__(self, name = None, xmin = None, xmax = None):
+        self.__n = 0
+        self.__name = name
+        self.__xmin = xmin
+        self.__xmax = xmax
+        self.__points = []
+
+    def __str__(self):
+        return '<PointTier "%s" with %d points>' % (self.__name, self.__n)
+
+    def __iter__(self):
+        return iter(self.__points)
+    
+    def __len__(self):
+        return self.__n
+    
+    def __getitem__(self, i):
+        """ return the (i-1)th tier """
+        return self.__points[i]
+
+    def name(self):
+        return self.__name
+
+    def xmin(self):
+        return self.__xmin
+
+    def xmax(self): 
+        return self.__xmax
+
+    def append(self, point):
+        self.__points.append(point)
+        ## MS: points don't have xmax, right?
+        # self.__xmax = point.xmax()
+        if self.__xmax is None:
+            self.__xmax = point.time()
+        else:
+            self.__max = max(point.time(), self.__xmax)
+        ## MS: do we then need to do this for xmin as well?
+        self.__n += 1
+
+    def read(self, file):
+        text = open(file, 'r')
+        text.readline() # header junk 
+        text.readline()
+        text.readline()
+        self.__xmin = float(text.readline().rstrip().split()[2])
+        self.__xmax = float(text.readline().rstrip().split()[2])
+        self.__n = int(text.readline().rstrip().split()[3])
+        for i in range(self.__n):
+            text.readline().rstrip() # header
+            itim = float(text.readline().rstrip().split()[2])
+            imrk = text.readline().rstrip().split()[2].replace('"', '') # txt
+            self.__points.append(Point(imrk, itim))
+        text.close()
+
+    def write(self, file):
+        text = open(file, 'w')
+        text.write('File type = "ooTextFile"\n')
+        text.write('Object class = "TextTier"\n\n')
+        text.write('xmin = %f\n' % self.__xmin)
+        text.write('xmax = %f\n' % self.__xmax)
+        text.write('points: size = %d\n' % self.__n)
+        for (point, n) in zip(self.__points, range(1, self.__n + 1)):
+            text.write('points [%d]:\n' % n)
+            text.write('\ttime = %f\n' % point.time())
+            text.write('\tmark = "%s"\n' % point.mark())
+        text.close()
+
+class Interval:
+    """ represent an Interval """
+    def __init__(self, xmin, xmax, mark):
+        self.__xmin = xmin
+        self.__xmax = xmax
+        self.__mark = mark
+    
+    def __str__(self):
+        return '<Interval "%s" %f:%f>' % (self.__mark, self.__xmin, self.__xmax)
+
+    def xmin(self):
+        return self.__xmin
+
+    def xmax(self):
+        return self.__xmax
+
+    # Morgan Sonderegger added
+    def bounds(self):
+        return (self.__xmin, self.__xmax)
+    
+    def mark(self):
+        return self.__mark
+
+class Point:
+    """ represent a Point """
+    def __init__(self, time, mark):
+        self.__time = time
+        self.__mark = mark
+    
+    def __str__(self):
+        return '<Point "%s" at %f>' % (self.__mark, self.__time)
+
+    def time(self):
+        return self.__time
+
+    def mark(self):
+        return self.__mark
+
+# Morgan Sonderegger added: account for intervals with writing beginning with whitespace
+#def correctLine(line):
+def getMark(text):
+    line = text.readline().rstrip()
+    a = re.search('(\S+) (=) (".*")', line)
+    assert(a)
+    assert(len(a.groups())==3)
+    return a.groups()[2][1:-1]
+    

helpers/textgrid2csv.py

@@ -0,0 +1,45 @@
+
+import argparse
+import csv
+import os
+from textgrid import *
+
+if __name__ == "__main__":
+    # parse arguments
+    parser = argparse.ArgumentParser(description='Convert a VOT tier fo a TextGrid to a CSV file. The CSV file will '
+                                                 'contain the filename, the duration of the mark, and the mark name.')
+    parser.add_argument('textgrid_filename', help="name of an input TextGrid file")
+    parser.add_argument('csv_filename', help="name of an output CSV file.")
+    parser.add_argument('tier', help='the tier name of the TextGrid that should be converted to CSV.')
+    args = parser.parse_args()
+
+
+    out_file = open(args.csv_filename, 'wb')
+    csv_file = csv.writer(out_file)
+    csv_file.writerow(['textgrid_file','time','vot','mark'])
+
+    # read TextGrid
+    textgrid = TextGrid()
+    textgrid.read(args.textgrid_filename)
+
+    # extract tier names
+    tier_names = textgrid.tierNames()
+
+    basename = os.path.splitext(os.path.basename(args.textgrid_filename))[0]
+
+    # check if the VOT tier is one of the tiers in the TextGrid
+    if args.tier in tier_names:
+        tier_index = tier_names.index(args.tier)
+        # run over all intervals in the tier
+        for interval in textgrid[tier_index]:
+            if re.search(r'\S', interval.mark()):
+                intervals = list()
+                intervals.append(basename)
+                intervals.append("{:.3f}".format(interval.xmin()))
+                intervals.append("{:.3f}".format(interval.xmax()-interval.xmin()))
+                intervals.append(interval.mark())
+                csv_file.writerow(intervals)
+                #print intervals
+    # close CSV file
+    out_file.close()
+

helpers/utilities.py

@@ -0,0 +1,171 @@
+# Copyright (c) 2014 Joseph Keshet, Morgan Sonderegger, Thea Knowles
+#
+# This file is part of Autovot, a package for automatic extraction of
+# voice onset time (VOT) from audio files.
+#
+# Autovot is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# Autovot is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with Autovot.  If not, see
+# <http://www.gnu.org/licenses/>.
+#
+
+import subprocess
+import random
+import logging
+import wave
+import tempfile
+import os
+
+
+def csv_append_row(tmp_preds, preds_filename, with_headers=True):
+
+    if with_headers:
+        skip_header = True
+
+    all_lines = list()
+
+    # check if the CSV file exists
+    if os.path.isfile(preds_filename):
+        # read it lines
+        for line in open(preds_filename, 'r'):
+            all_lines.append(line)
+    else:
+        # if the file does not exist it does not have headers and they should be copied
+        skip_header = False
+
+    # check if there is a header
+    for line in open(tmp_preds, 'r'):
+        if skip_header:
+            skip_header = False
+        else:
+            all_lines.append(line)
+    # now dump everything back
+    with open(preds_filename, 'w') as f:
+        for line in all_lines:
+            f.write(line)
+
+
+
+def generate_tmp_filename():
+    return tempfile._get_default_tempdir() + "/" + next(tempfile._get_candidate_names()) + ".txt"
+
+
+def logging_defaults(logging_level="INFO"):
+    logging.basicConfig(level=logging_level, format='%(asctime)s.%(msecs)d [%(filename)s] %(levelname)s: %(message)s',
+                        datefmt='%H:%M:%S')
+
+def num_lines(filename):
+    lines = 0
+    for _ in open(filename, 'rU'):
+        lines += 1
+    return lines
+
+
+def easy_call(command):
+    try:
+        logging.debug(command)
+        return_code = subprocess.call(command, shell=True)
+        if return_code == 127 or return_code < 0:
+            logging.debug('Return code: %d' % return_code)
+            exit(-1)
+    except Exception as exception:
+        logging.error('Could not execute the following:')
+        logging.error(command)
+        logging.error('%s - %s' % (type(exception), exception.args))
+        exit(-1)
+
+
+def random_shuffle_data(in_features_filename, in_labels_filename, out_features_filename, out_labels_filename):
+
+    # open files
+    in_features = open(in_features_filename, 'rU')
+    in_labels = open(in_labels_filename, 'rU')
+
+    # read infra text header
+    header = in_labels.readline()
+    dims = header.split()
+
+    # read file lines
+    lines = list()
+    for x, y in zip(in_features, in_labels):
+        lines.append((x, y))
+    if len(lines) != int(dims[0]):
+        logging.error("Either the feature file and the label file are not the same length of label file missing a "
+                      "header")
+        exit(-1)
+
+    # close files
+    in_features.close()
+    in_labels.close()
+
+    # random shuffle the instances
+    random.shuffle(lines)
+
+    # write back the result
+    out_features = open(out_features_filename, 'w')
+    out_labels = open(out_labels_filename, 'w')
+
+    # write labels header
+    header = "%s %s\n" % (dims[0], dims[1])
+    out_labels.write(header)
+
+    # write data
+    for x, y in lines:
+        out_features.write(x)
+        out_labels.write(y)
+
+    # close files
+    out_features.close()
+    out_labels.close()
+
+    return len(lines)
+
+
+def extract_lines(input_filename, output_filename, lines_range, has_header=False):
+
+    if lines_range[0] >= lines_range[1]:
+        logging.error("Range should be causal.")
+        exit(-1)
+    input_file = open(input_filename, 'rU')
+    output_file = open(output_filename, 'w')
+    if has_header:
+        header = input_file.readline().strip().split()
+        new_header = "%d 2\n" % (lines_range[1]-lines_range[0]+1)
+        output_file.write(new_header)
+    for line_num, line in enumerate(input_file):
+        if lines_range[0] <= line_num <= lines_range[1]:
+            output_file.write(line)
+    input_file.close()
+    output_file.close()
+
+
+def is_textgrid(filename):
+    try:
+        file = open(filename, 'rU')
+        first_line = file.readline()
+    except:
+        return False
+    if "ooTextFile" in first_line:
+        return True
+    return False
+
+
+def is_valid_wav(filename):
+    # check the sampling rate and number bits of the WAV
+    try:
+        wav_file = wave.Wave_read(filename)
+    except:
+        return False
+    if wav_file.getframerate() != 16000 or wav_file.getsampwidth() != 2 or wav_file.getnchannels() != 1 \
+        or wav_file.getcomptype() != 'NONE':
+        return False
+    return True