Make prefer_free_formats sorting more robust

diff --git a/youtube_dl/YoutubeDL.py b/youtube_dl/YoutubeDL.py
index fd26f00b721c05f8889ad07ad9e119451ab96251..a93dd41a315ce49f3d7325249fa1b267d8565ee7 100644 (file)
--- a/youtube_dl/YoutubeDL.py
+++ b/youtube_dl/YoutubeDL.py
@@ -674,7 +674,9 @@ class YoutubeDL(object):
                 except ValueError:
                     ext_ord = -1
                 # We only compare the extension if they have the same height and width
-                return (f.get('height'), f.get('width'), ext_ord)
+                return (f.get('height') if f.get('height') is not None else -1,
+                        f.get('width') if f.get('width') is not None else -1,
+                        ext_ord)
             formats = sorted(formats, key=_free_formats_key)
 
         info_dict['formats'] = formats