diff --git a/tools/barcode_tools/barcode_decoder.py b/tools/barcode_tools/barcode_decoder.py
index 87b3ec2993..362a794f6b 100755
--- a/tools/barcode_tools/barcode_decoder.py
+++ b/tools/barcode_tools/barcode_decoder.py
@@ -35,7 +35,14 @@ def convert_yuv_to_png_files(yuv_file_name, yuv_frame_width, yuv_frame_height,
   """
   size_string = str(yuv_frame_width) + 'x' + str(yuv_frame_height)
   output_files_pattern = os.path.join(output_directory, 'frame_%04d.png')
-  command = ['ffmpeg', '-s', '%s' % size_string, '-i', '%s'
+  ffmpeg_executable = 'ffmpeg'
+  if sys.platform == 'win32':
+    if os.getenv('FFMPEG_HOME'):
+      ffmpeg_executable = os.path.join(os.getenv('FFMPEG_HOME'), 'bin',
+                                       'ffmpeg.exe')
+    else:
+      ffmpeg_executable = 'ffmpeg.exe'
+  command = [ffmpeg_executable, '-s', '%s' % size_string, '-i', '%s'
              % yuv_file_name, '-f', 'image2', '-vcodec', 'png',
              '%s' % output_files_pattern]
   try:
@@ -92,7 +99,14 @@ def _decode_barcode_in_file(file_name, barcode_width, barcode_height, jars,
   Return:
     (bool): True upon success, False otherwise.
   """
-  command = ['java', '-Djava.awt.headless=true', '-cp', '%s' % jars,
+  java_executable = 'java'
+  if sys.platform == 'win32':
+    if os.getenv('JAVA_HOME'):
+      java_executable = os.path.join(os.getenv('JAVA_HOME'), 'bin',
+                                     'java.exe')
+    else:
+      java_executable = 'java.exe'
+  command = [java_executable, '-Djava.awt.headless=true', '-cp', '%s' % jars,
              '%s' % command_line_decoder, '--products_only',
              '--dump_results', '--brief', '--crop=%d,%d,%d,%d' %
              (0, 0, barcode_width, barcode_height),
@@ -257,6 +271,10 @@ def _main():
   --yuv_file=<path_and_name_of_overlaid_yuv_video>
   --yuv_frame_width=352 --yuv_frame_height=288 --barcode_height=32
   --stats_file=<path_and_name_to_stats_file>
+
+  NOTE: On Windows, if you don't have ffmpeg and Java in your PATH, you can
+  set the JAVA_HOME and FFMPEG_HOME environment variables to help the script
+  find the executables to use.
   """
   options = _parse_args()
 
diff --git a/tools/barcode_tools/build_zxing.py b/tools/barcode_tools/build_zxing.py
index 9e737f2f70..5656a46a51 100755
--- a/tools/barcode_tools/build_zxing.py
+++ b/tools/barcode_tools/build_zxing.py
@@ -14,28 +14,29 @@ import sys
 
 def run_ant_build_command(path_to_ant_build_file):
   """Tries to build the passed build file with ant."""
-  ant_suffix = '.bat' if 'win32' in sys.platform else ''
-  cmd = ['ant%s' % ant_suffix, '-buildfile', path_to_ant_build_file]
-  try:
-    process = subprocess.Popen(cmd, stdout=subprocess.PIPE,
-                               stderr=subprocess.PIPE)
-    stdout, stderr = process.communicate()
-    if process.returncode != 0:
-      print >> sys.stderr, 'Failed to execute: %s\nError: %s' % (' '.join(cmd),
-                                                                 stderr)
+  ant_executable = 'ant'
+  if sys.platform == 'win32':
+    if os.getenv('ANT_HOME'):
+      ant_executable = os.path.join(os.getenv('ANT_HOME'), 'bin', 'ant.bat')
     else:
-      print stdout
+      ant_executable = 'ant.bat'
+  cmd = [ant_executable, '-buildfile', path_to_ant_build_file]
+  try:
+    process = subprocess.Popen(cmd, stdout=sys.stdout, stderr=sys.stderr)
+    process.wait()
+    if process.returncode != 0:
+      print >> sys.stderr, 'Failed to execute: %s' % ' '.join(cmd)
+    return process.returncode
   except Exception as e:
-    print >> sys.stderr, 'Failed to execute: %s\nError: %s' % (' '.join(cmd), e)
-
+    print >> sys.stderr, 'Failed to execute: %s' % ' '.join(cmd)
+    return -1
 
 def _main():
   core_build = os.path.join('third_party', 'zxing', 'core', 'build.xml')
   run_ant_build_command(core_build)
 
   javase_build = os.path.join('third_party', 'zxing', 'javase', 'build.xml')
-  run_ant_build_command(javase_build)
-  return 0
+  return run_ant_build_command(javase_build)
 
 
 if __name__ == '__main__':