[extractor/common] Respect Width and Height attributes in ISM manifests

youtube_dl/extractor/common.py

@@ -2001,6 +2001,12 @@ class InfoExtractor(object):
             compat_etree_fromstring(ism.encode('utf-8')), urlh.geturl(), ism_id)
 
     def _parse_ism_formats(self, ism_doc, ism_url, ism_id=None):
+        """
+        Parse formats from ISM manifest.
+        References:
+         1. [MS-SSTR]: Smooth Streaming Protocol,
+            https://msdn.microsoft.com/en-us/library/ff469518.aspx
+        """
         if ism_doc.get('IsLive') == 'TRUE' or ism_doc.find('Protection') is not None:
             return []
 
@@ -2022,8 +2028,11 @@ class InfoExtractor(object):
                     self.report_warning('%s is not a supported codec' % fourcc)
                     continue
                 tbr = int(track.attrib['Bitrate']) // 1000
-                width = int_or_none(track.get('MaxWidth'))
+                # [1] does not mention Width and Height attributes. However,
-                height = int_or_none(track.get('MaxHeight'))
+                # they're often present while MaxWidth and MaxHeight are
+                # missing, so should be used as fallbacks
+                width = int_or_none(track.get('MaxWidth') or track.get('Width'))
+                height = int_or_none(track.get('MaxHeight') or track.get('Height'))
                 sampling_rate = int_or_none(track.get('SamplingRate'))
 
                 track_url_pattern = re.sub(r'{[Bb]itrate}', track.attrib['Bitrate'], url_pattern)