[nba] handle format info properly

youtube_dl/extractor/nba.py

@@ -77,14 +77,18 @@ class NBAIE(InfoExtractor):
                     formats.extend(f4m_formats)
             else:
                 key = video_file.attrib.get('bitrate')
-                mobj = re.search(r'(\d+)x(\d+)(?:_(\d+))?', key)
-                formats.append({
+                format_info = {
                     'format_id': key,
                     'url': video_url,
+                }
+                mobj = re.search(r'(\d+)x(\d+)(?:_(\d+))?', key)
+                if mobj:
+                    format_info.update({
                         'width': int_or_none(mobj.group(1)),
                         'height': int_or_none(mobj.group(2)),
                         'tbr': int_or_none(mobj.group(3)),
                     })
+                formats.append(format_info)
         self._sort_formats(formats)
 
         return {