diff --git a/coub-dl.py b/coub-dl.py
index b8a894a..1d65c14 100644
--- a/coub-dl.py
+++ b/coub-dl.py
@@ -1,6 +1,6 @@
 from subprocess import call, Popen, PIPE, check_output, DEVNULL
 from os import listdir, remove
-from os.path import splitext, exists
+from os.path import splitext, exists, join
 from re import match
 from enum import Enum
 from datetime import timedelta
@@ -73,7 +73,7 @@ def download_video_stream(url, file_dict):
 def read_extensions(file_dict, directory):
     for file in listdir(directory):
         for filename in file_dict:
-            fullname = '{}/{}'.format(directory, file)
+            fullname = join(directory, file)
             if match('^{}.*'.format(file_dict[filename]), fullname):
                 file_dict[filename] = fullname
 
@@ -104,6 +104,27 @@ def get_length(file):
     return timedelta(hours=float(data[0]), minutes=float(data[1]), seconds=float(data[2]))
 
 
+def determine_output_filename(url, user_supplied, extension, files_dict):
+    if user_supplied is None:
+        files_dict[File.OUTPUT] = check_output(('youtube-dl', '--get-title', url)).decode('utf-8').strip()
+    else:
+        files_dict[File.OUTPUT] = user_supplied
+    files_dict[File.OUTPUT] += extension
+
+
+def parse_cmd_arguments():
+    parser = ArgumentParser(description='Download player-looped videos with youtube-dl & ffmpeg.')
+    parser.add_argument('-nv', '--nonverbose', action='store_true', help='Turn off non-critical messages to user.')
+    parser.add_argument('-o', '--output', default=None, help='Specify name of the output file (use -e for extension).')
+    parser.add_argument('-e', '--extension', default='mp4', help='Set the container to use for the output.')
+    parser.add_argument('url', type=str, help='The URL of the site containing the video to download.')
+
+    args = parser.parse_args()
+    args.extension = '.' + args.extension
+
+    return args
+
+
 def yes_no_question(question, default):
     valid = {"yes": True, "y": True, "ye": True,
              "no": False, "n": False}
@@ -160,15 +181,7 @@ def run(url, files_dict, directory):
 
 
 if __name__ == '__main__':
-    # parse arguments
-    parser = ArgumentParser(description='Download player-looped videos with youtube-dl & ffmpeg.')
-    parser.add_argument('-nv', '--nonverbose', action='store_true', help='Turn off non-critical messages to user.')
-    parser.add_argument('-o', '--output', default=None, help='Specify name of the output file (use -e for extension).')
-    parser.add_argument('-e', '--extension', default='mp4', help='Set the container to use for the output.')
-    parser.add_argument('url', type=str, help='The URL of the site containing the video to download.')
-
-    args = parser.parse_args()
-    args.extension = '.' + args.extension
+    args = parse_cmd_arguments()
     VERBOSE = False if args.nonverbose else True
 
     FILES = {Stream.AUDIO: 'audio', Stream.VIDEO: 'video',
@@ -177,12 +190,7 @@ if __name__ == '__main__':
     OUTPUT_KEYS = [File.OUTPUT]
     URL = args.url
 
-    # fetch video title if no filename was specified
-    if args.output is None:
-        FILES[File.OUTPUT] = check_output(('youtube-dl', '--get-title', args.url)).decode('utf-8').strip()
-    else:
-        FILES[File.OUTPUT] = args.output
-    FILES[File.OUTPUT] += args.extension
+    determine_output_filename(URL, args.output, args.extension, FILES)
 
     # ask what to do if output exists
     if exists(FILES[File.OUTPUT]):
@@ -195,8 +203,9 @@ if __name__ == '__main__':
             remove(FILES[File.OUTPUT])
 
     with TemporaryDirectory() as dir:
+        # update temporary file locations in FILES dict
         for key in FILES:
             if key not in OUTPUT_KEYS:
-                FILES[key] = '{}/{}'.format(dir, FILES[key])
+                FILES[key] = join(dir, FILES[key])
 
         run(URL, FILES, dir)