diff --git a/youtube_dl/extractor/ooyala.py b/youtube_dl/extractor/ooyala.py
index 84be2b1e3f..ef8adccc14 100644
--- a/youtube_dl/extractor/ooyala.py
+++ b/youtube_dl/extractor/ooyala.py
@@ -41,7 +41,7 @@ def _extract(self, content_tree_url, video_id, domain='example.org', supportedfo
             for stream in cur_auth_data['streams']:
                 s_url = base64.b64decode(
                     stream['url']['data'].encode('ascii')).decode('utf-8')
-                if s_url in urls:
+                if not s_url or s_url in urls:
                     continue
                 urls.append(s_url)
                 ext = determine_ext(s_url, None)