diff --git a/datasets/pascalvoc_to_tfrecords.py b/datasets/pascalvoc_to_tfrecords.py
index 9ac20169b..e008a1b99 100644
--- a/datasets/pascalvoc_to_tfrecords.py
+++ b/datasets/pascalvoc_to_tfrecords.py
@@ -79,8 +79,8 @@ def _process_image(directory, name):
       width: integer, image width in pixels.
     """
     # Read the image file.
-    filename = directory + DIRECTORY_IMAGES + name + '.jpg'
-    image_data = tf.gfile.FastGFile(filename, 'r').read()
+    filename = os.path.join(directory, DIRECTORY_IMAGES, '{}.jpg'.format(name))
+    image_data = tf.gfile.FastGFile(filename, 'rb').read()
 
     # Read the XML annotation file.
     filename = os.path.join(directory, DIRECTORY_ANNOTATIONS, name + '.xml')