youtube-dl

common.py (143736B)

---

 # coding: utf-8
 from __future__ import unicode_literals
 
 import base64
 import datetime
 import hashlib
 import json
 import netrc
 import os
 import random
 import re
 import socket
 import ssl
 import sys
 import time
 import math
 
 from ..compat import (
     compat_cookiejar_Cookie,
     compat_cookies_SimpleCookie,
     compat_etree_Element,
     compat_etree_fromstring,
     compat_getpass,
     compat_integer_types,
     compat_http_client,
     compat_os_name,
     compat_str,
     compat_urllib_error,
     compat_urllib_parse_unquote,
     compat_urllib_parse_urlencode,
     compat_urllib_request,
     compat_urlparse,
     compat_xml_parse_error,
 )
 from ..downloader.f4m import (
     get_base_url,
     remove_encrypted_media,
 )
 from ..utils import (
     NO_DEFAULT,
     age_restricted,
     base_url,
     bug_reports_message,
     clean_html,
     compiled_regex_type,
     determine_ext,
     determine_protocol,
     dict_get,
     error_to_compat_str,
     ExtractorError,
     extract_attributes,
     fix_xml_ampersands,
     float_or_none,
     GeoRestrictedError,
     GeoUtils,
     int_or_none,
     js_to_json,
     JSON_LD_RE,
     mimetype2ext,
     orderedSet,
     parse_bitrate,
     parse_codecs,
     parse_duration,
     parse_iso8601,
     parse_m3u8_attributes,
     parse_resolution,
     RegexNotFoundError,
     sanitized_Request,
     sanitize_filename,
     str_or_none,
     str_to_int,
     strip_or_none,
     unescapeHTML,
     unified_strdate,
     unified_timestamp,
     update_Request,
     update_url_query,
     urljoin,
     url_basename,
     url_or_none,
     xpath_element,
     xpath_text,
     xpath_with_ns,
 )
 
 
 class InfoExtractor(object):
     """Information Extractor class.
 
     Information extractors are the classes that, given a URL, extract
     information about the video (or videos) the URL refers to. This
     information includes the real video URL, the video title, author and
     others. The information is stored in a dictionary which is then
     passed to the YoutubeDL. The YoutubeDL processes this
     information possibly downloading the video to the file system, among
     other possible outcomes.
 
     The type field determines the type of the result.
     By far the most common value (and the default if _type is missing) is
     "video", which indicates a single video.
 
     For a video, the dictionaries must include the following fields:
 
     id:             Video identifier.
     title:          Video title, unescaped.
 
     Additionally, it must contain either a formats entry or a url one:
 
     formats:        A list of dictionaries for each format available, ordered
                     from worst to best quality.
 
                     Potential fields:
                     * url        The mandatory URL representing the media:
                                    for plain file media - HTTP URL of this file,
                                    for RTMP - RTMP URL,
                                    for HLS - URL of the M3U8 media playlist,
                                    for HDS - URL of the F4M manifest,
                                    for DASH
                                      - HTTP URL to plain file media (in case of
                                        unfragmented media)
                                      - URL of the MPD manifest or base URL
                                        representing the media if MPD manifest
                                        is parsed from a string (in case of
                                        fragmented media)
                                    for MSS - URL of the ISM manifest.
                     * manifest_url
                                  The URL of the manifest file in case of
                                  fragmented media:
                                    for HLS - URL of the M3U8 master playlist,
                                    for HDS - URL of the F4M manifest,
                                    for DASH - URL of the MPD manifest,
                                    for MSS - URL of the ISM manifest.
                     * ext        Will be calculated from URL if missing
                     * format     A human-readable description of the format
                                  ("mp4 container with h264/opus").
                                  Calculated from the format_id, width, height.
                                  and format_note fields if missing.
                     * format_id  A short description of the format
                                  ("mp4_h264_opus" or "19").
                                 Technically optional, but strongly recommended.
                     * format_note Additional info about the format
                                  ("3D" or "DASH video")
                     * width      Width of the video, if known
                     * height     Height of the video, if known
                     * resolution Textual description of width and height
                     * tbr        Average bitrate of audio and video in KBit/s
                     * abr        Average audio bitrate in KBit/s
                     * acodec     Name of the audio codec in use
                     * asr        Audio sampling rate in Hertz
                     * vbr        Average video bitrate in KBit/s
                     * fps        Frame rate
                     * vcodec     Name of the video codec in use
                     * container  Name of the container format
                     * filesize   The number of bytes, if known in advance
                     * filesize_approx  An estimate for the number of bytes
                     * player_url SWF Player URL (used for rtmpdump).
                     * protocol   The protocol that will be used for the actual
                                  download, lower-case.
                                  "http", "https", "rtsp", "rtmp", "rtmpe",
                                  "m3u8", "m3u8_native" or "http_dash_segments".
                     * fragment_base_url
                                  Base URL for fragments. Each fragment's path
                                  value (if present) will be relative to
                                  this URL.
                     * fragments  A list of fragments of a fragmented media.
                                  Each fragment entry must contain either an url
                                  or a path. If an url is present it should be
                                  considered by a client. Otherwise both path and
                                  fragment_base_url must be present. Here is
                                  the list of all potential fields:
                                  * "url" - fragment's URL
                                  * "path" - fragment's path relative to
                                             fragment_base_url
                                  * "duration" (optional, int or float)
                                  * "filesize" (optional, int)
                     * preference Order number of this format. If this field is
                                  present and not None, the formats get sorted
                                  by this field, regardless of all other values.
                                  -1 for default (order by other properties),
                                  -2 or smaller for less than default.
                                  < -1000 to hide the format (if there is
                                     another one which is strictly better)
                     * language   Language code, e.g. "de" or "en-US".
                     * language_preference  Is this in the language mentioned in
                                  the URL?
                                  10 if it's what the URL is about,
                                  -1 for default (don't know),
                                  -10 otherwise, other values reserved for now.
                     * quality    Order number of the video quality of this
                                  format, irrespective of the file format.
                                  -1 for default (order by other properties),
                                  -2 or smaller for less than default.
                     * source_preference  Order number for this video source
                                   (quality takes higher priority)
                                  -1 for default (order by other properties),
                                  -2 or smaller for less than default.
                     * http_headers  A dictionary of additional HTTP headers
                                  to add to the request.
                     * stretched_ratio  If given and not 1, indicates that the
                                  video's pixels are not square.
                                  width : height ratio as float.
                     * no_resume  The server does not support resuming the
                                  (HTTP or RTMP) download. Boolean.
                     * downloader_options  A dictionary of downloader options as
                                  described in FileDownloader
 
     url:            Final video URL.
     ext:            Video filename extension.
     format:         The video format, defaults to ext (used for --get-format)
     player_url:     SWF Player URL (used for rtmpdump).
 
     The following fields are optional:
 
     alt_title:      A secondary title of the video.
     display_id      An alternative identifier for the video, not necessarily
                     unique, but available before title. Typically, id is
                     something like "4234987", title "Dancing naked mole rats",
                     and display_id "dancing-naked-mole-rats"
     thumbnails:     A list of dictionaries, with the following entries:
                         * "id" (optional, string) - Thumbnail format ID
                         * "url"
                         * "preference" (optional, int) - quality of the image
                         * "width" (optional, int)
                         * "height" (optional, int)
                         * "resolution" (optional, string "{width}x{height}",
                                         deprecated)
                         * "filesize" (optional, int)
     thumbnail:      Full URL to a video thumbnail image.
     description:    Full video description.
     uploader:       Full name of the video uploader.
     license:        License name the video is licensed under.
     creator:        The creator of the video.
     release_timestamp: UNIX timestamp of the moment the video was released.
     release_date:   The date (YYYYMMDD) when the video was released.
     timestamp:      UNIX timestamp of the moment the video became available
                     (uploaded).
     upload_date:    Video upload date (YYYYMMDD).
                     If not explicitly set, calculated from timestamp.
     uploader_id:    Nickname or id of the video uploader.
     uploader_url:   Full URL to a personal webpage of the video uploader.
     channel:        Full name of the channel the video is uploaded on.
                     Note that channel fields may or may not repeat uploader
                     fields. This depends on a particular extractor.
     channel_id:     Id of the channel.
     channel_url:    Full URL to a channel webpage.
     location:       Physical location where the video was filmed.
     subtitles:      The available subtitles as a dictionary in the format
                     {tag: subformats}. "tag" is usually a language code, and
                     "subformats" is a list sorted from lower to higher
                     preference, each element is a dictionary with the "ext"
                     entry and one of:
                         * "data": The subtitles file contents
                         * "url": A URL pointing to the subtitles file
                     "ext" will be calculated from URL if missing
     automatic_captions: Like 'subtitles', used by the YoutubeIE for
                     automatically generated captions
     duration:       Length of the video in seconds, as an integer or float.
     view_count:     How many users have watched the video on the platform.
     like_count:     Number of positive ratings of the video
     dislike_count:  Number of negative ratings of the video
     repost_count:   Number of reposts of the video
     average_rating: Average rating give by users, the scale used depends on the webpage
     comment_count:  Number of comments on the video
     comments:       A list of comments, each with one or more of the following
                     properties (all but one of text or html optional):
                         * "author" - human-readable name of the comment author
                         * "author_id" - user ID of the comment author
                         * "id" - Comment ID
                         * "html" - Comment as HTML
                         * "text" - Plain text of the comment
                         * "timestamp" - UNIX timestamp of comment
                         * "parent" - ID of the comment this one is replying to.
                                      Set to "root" to indicate that this is a
                                      comment to the original video.
     age_limit:      Age restriction for the video, as an integer (years)
     webpage_url:    The URL to the video webpage, if given to youtube-dl it
                     should allow to get the same result again. (It will be set
                     by YoutubeDL if it's missing)
     categories:     A list of categories that the video falls in, for example
                     ["Sports", "Berlin"]
     tags:           A list of tags assigned to the video, e.g. ["sweden", "pop music"]
     is_live:        True, False, or None (=unknown). Whether this video is a
                     live stream that goes on instead of a fixed-length video.
     start_time:     Time in seconds where the reproduction should start, as
                     specified in the URL.
     end_time:       Time in seconds where the reproduction should end, as
                     specified in the URL.
     chapters:       A list of dictionaries, with the following entries:
                         * "start_time" - The start time of the chapter in seconds
                         * "end_time" - The end time of the chapter in seconds
                         * "title" (optional, string)
 
     The following fields should only be used when the video belongs to some logical
     chapter or section:
 
     chapter:        Name or title of the chapter the video belongs to.
     chapter_number: Number of the chapter the video belongs to, as an integer.
     chapter_id:     Id of the chapter the video belongs to, as a unicode string.
 
     The following fields should only be used when the video is an episode of some
     series, programme or podcast:
 
     series:         Title of the series or programme the video episode belongs to.
     season:         Title of the season the video episode belongs to.
     season_number:  Number of the season the video episode belongs to, as an integer.
     season_id:      Id of the season the video episode belongs to, as a unicode string.
     episode:        Title of the video episode. Unlike mandatory video title field,
                     this field should denote the exact title of the video episode
                     without any kind of decoration.
     episode_number: Number of the video episode within a season, as an integer.
     episode_id:     Id of the video episode, as a unicode string.
 
     The following fields should only be used when the media is a track or a part of
     a music album:
 
     track:          Title of the track.
     track_number:   Number of the track within an album or a disc, as an integer.
     track_id:       Id of the track (useful in case of custom indexing, e.g. 6.iii),
                     as a unicode string.
     artist:         Artist(s) of the track.
     genre:          Genre(s) of the track.
     album:          Title of the album the track belongs to.
     album_type:     Type of the album (e.g. "Demo", "Full-length", "Split", "Compilation", etc).
     album_artist:   List of all artists appeared on the album (e.g.
                     "Ash Borer / Fell Voices" or "Various Artists", useful for splits
                     and compilations).
     disc_number:    Number of the disc or other physical medium the track belongs to,
                     as an integer.
     release_year:   Year (YYYY) when the album was released.
 
     Unless mentioned otherwise, the fields should be Unicode strings.
 
     Unless mentioned otherwise, None is equivalent to absence of information.
 
 
     _type "playlist" indicates multiple videos.
     There must be a key "entries", which is a list, an iterable, or a PagedList
     object, each element of which is a valid dictionary by this specification.
 
     Additionally, playlists can have "id", "title", "description", "uploader",
     "uploader_id", "uploader_url", "duration" attributes with the same semantics
     as videos (see above).
 
 
     _type "multi_video" indicates that there are multiple videos that
     form a single show, for examples multiple acts of an opera or TV episode.
     It must have an entries key like a playlist and contain all the keys
     required for a video at the same time.
 
 
     _type "url" indicates that the video must be extracted from another
     location, possibly by a different extractor. Its only required key is:
     "url" - the next URL to extract.
     The key "ie_key" can be set to the class name (minus the trailing "IE",
     e.g. "Youtube") if the extractor class is known in advance.
     Additionally, the dictionary may have any properties of the resolved entity
     known in advance, for example "title" if the title of the referred video is
     known ahead of time.
 
 
     _type "url_transparent" entities have the same specification as "url", but
     indicate that the given additional information is more precise than the one
     associated with the resolved URL.
     This is useful when a site employs a video service that hosts the video and
     its technical metadata, but that video service does not embed a useful
     title, description etc.
 
 
     Subclasses of this one should re-define the _real_initialize() and
     _real_extract() methods and define a _VALID_URL regexp.
     Probably, they should also be added to the list of extractors.
 
     _GEO_BYPASS attribute may be set to False in order to disable
     geo restriction bypass mechanisms for a particular extractor.
     Though it won't disable explicit geo restriction bypass based on
     country code provided with geo_bypass_country.
 
     _GEO_COUNTRIES attribute may contain a list of presumably geo unrestricted
     countries for this extractor. One of these countries will be used by
     geo restriction bypass mechanism right away in order to bypass
     geo restriction, of course, if the mechanism is not disabled.
 
     _GEO_IP_BLOCKS attribute may contain a list of presumably geo unrestricted
     IP blocks in CIDR notation for this extractor. One of these IP blocks
     will be used by geo restriction bypass mechanism similarly
     to _GEO_COUNTRIES.
 
     Finally, the _WORKING attribute should be set to False for broken IEs
     in order to warn the users and skip the tests.
     """
 
     _ready = False
     _downloader = None
     _x_forwarded_for_ip = None
     _GEO_BYPASS = True
     _GEO_COUNTRIES = None
     _GEO_IP_BLOCKS = None
     _WORKING = True
 
     def __init__(self, downloader=None):
         """Constructor. Receives an optional downloader."""
         self._ready = False
         self._x_forwarded_for_ip = None
         self.set_downloader(downloader)
 
     @classmethod
     def suitable(cls, url):
         """Receives a URL and returns True if suitable for this IE."""
 
         # This does not use has/getattr intentionally - we want to know whether
         # we have cached the regexp for *this* class, whereas getattr would also
         # match the superclass
         if '_VALID_URL_RE' not in cls.__dict__:
             cls._VALID_URL_RE = re.compile(cls._VALID_URL)
         return cls._VALID_URL_RE.match(url) is not None
 
     @classmethod
     def _match_id(cls, url):
         if '_VALID_URL_RE' not in cls.__dict__:
             cls._VALID_URL_RE = re.compile(cls._VALID_URL)
         m = cls._VALID_URL_RE.match(url)
         assert m
         return compat_str(m.group('id'))
 
     @classmethod
     def working(cls):
         """Getter method for _WORKING."""
         return cls._WORKING
 
     def initialize(self):
         """Initializes an instance (authentication, etc)."""
         self._initialize_geo_bypass({
             'countries': self._GEO_COUNTRIES,
             'ip_blocks': self._GEO_IP_BLOCKS,
         })
         if not self._ready:
             self._real_initialize()
             self._ready = True
 
     def _initialize_geo_bypass(self, geo_bypass_context):
         """
         Initialize geo restriction bypass mechanism.
 
         This method is used to initialize geo bypass mechanism based on faking
         X-Forwarded-For HTTP header. A random country from provided country list
         is selected and a random IP belonging to this country is generated. This
         IP will be passed as X-Forwarded-For HTTP header in all subsequent
         HTTP requests.
 
         This method will be used for initial geo bypass mechanism initialization
         during the instance initialization with _GEO_COUNTRIES and
         _GEO_IP_BLOCKS.
 
         You may also manually call it from extractor's code if geo bypass
         information is not available beforehand (e.g. obtained during
         extraction) or due to some other reason. In this case you should pass
         this information in geo bypass context passed as first argument. It may
         contain following fields:
 
         countries:  List of geo unrestricted countries (similar
                     to _GEO_COUNTRIES)
         ip_blocks:  List of geo unrestricted IP blocks in CIDR notation
                     (similar to _GEO_IP_BLOCKS)
 
         """
         if not self._x_forwarded_for_ip:
 
             # Geo bypass mechanism is explicitly disabled by user
             if not self._downloader.params.get('geo_bypass', True):
                 return
 
             if not geo_bypass_context:
                 geo_bypass_context = {}
 
             # Backward compatibility: previously _initialize_geo_bypass
             # expected a list of countries, some 3rd party code may still use
             # it this way
             if isinstance(geo_bypass_context, (list, tuple)):
                 geo_bypass_context = {
                     'countries': geo_bypass_context,
                 }
 
             # The whole point of geo bypass mechanism is to fake IP
             # as X-Forwarded-For HTTP header based on some IP block or
             # country code.
 
             # Path 1: bypassing based on IP block in CIDR notation
 
             # Explicit IP block specified by user, use it right away
             # regardless of whether extractor is geo bypassable or not
             ip_block = self._downloader.params.get('geo_bypass_ip_block', None)
 
             # Otherwise use random IP block from geo bypass context but only
             # if extractor is known as geo bypassable
             if not ip_block:
                 ip_blocks = geo_bypass_context.get('ip_blocks')
                 if self._GEO_BYPASS and ip_blocks:
                     ip_block = random.choice(ip_blocks)
 
             if ip_block:
                 self._x_forwarded_for_ip = GeoUtils.random_ipv4(ip_block)
                 if self._downloader.params.get('verbose', False):
                     self._downloader.to_screen(
                         '[debug] Using fake IP %s as X-Forwarded-For.'
                         % self._x_forwarded_for_ip)
                 return
 
             # Path 2: bypassing based on country code
 
             # Explicit country code specified by user, use it right away
             # regardless of whether extractor is geo bypassable or not
             country = self._downloader.params.get('geo_bypass_country', None)
 
             # Otherwise use random country code from geo bypass context but
             # only if extractor is known as geo bypassable
             if not country:
                 countries = geo_bypass_context.get('countries')
                 if self._GEO_BYPASS and countries:
                     country = random.choice(countries)
 
             if country:
                 self._x_forwarded_for_ip = GeoUtils.random_ipv4(country)
                 if self._downloader.params.get('verbose', False):
                     self._downloader.to_screen(
                         '[debug] Using fake IP %s (%s) as X-Forwarded-For.'
                         % (self._x_forwarded_for_ip, country.upper()))
 
     def extract(self, url):
         """Extracts URL information and returns it in list of dicts."""
         try:
             for _ in range(2):
                 try:
                     self.initialize()
                     ie_result = self._real_extract(url)
                     if self._x_forwarded_for_ip:
                         ie_result['__x_forwarded_for_ip'] = self._x_forwarded_for_ip
                     return ie_result
                 except GeoRestrictedError as e:
                     if self.__maybe_fake_ip_and_retry(e.countries):
                         continue
                     raise
         except ExtractorError:
             raise
         except compat_http_client.IncompleteRead as e:
             raise ExtractorError('A network error has occurred.', cause=e, expected=True)
         except (KeyError, StopIteration) as e:
             raise ExtractorError('An extractor error has occurred.', cause=e)
 
     def __maybe_fake_ip_and_retry(self, countries):
         if (not self._downloader.params.get('geo_bypass_country', None)
                 and self._GEO_BYPASS
                 and self._downloader.params.get('geo_bypass', True)
                 and not self._x_forwarded_for_ip
                 and countries):
             country_code = random.choice(countries)
             self._x_forwarded_for_ip = GeoUtils.random_ipv4(country_code)
             if self._x_forwarded_for_ip:
                 self.report_warning(
                     'Video is geo restricted. Retrying extraction with fake IP %s (%s) as X-Forwarded-For.'
                     % (self._x_forwarded_for_ip, country_code.upper()))
                 return True
         return False
 
     def set_downloader(self, downloader):
         """Sets the downloader for this IE."""
         self._downloader = downloader
 
     def _real_initialize(self):
         """Real initialization process. Redefine in subclasses."""
         pass
 
     def _real_extract(self, url):
         """Real extraction process. Redefine in subclasses."""
         pass
 
     @classmethod
     def ie_key(cls):
         """A string for getting the InfoExtractor with get_info_extractor"""
         return compat_str(cls.__name__[:-2])
 
     @property
     def IE_NAME(self):
         return compat_str(type(self).__name__[:-2])
 
     @staticmethod
     def __can_accept_status_code(err, expected_status):
         assert isinstance(err, compat_urllib_error.HTTPError)
         if expected_status is None:
             return False
         if isinstance(expected_status, compat_integer_types):
             return err.code == expected_status
         elif isinstance(expected_status, (list, tuple)):
             return err.code in expected_status
         elif callable(expected_status):
             return expected_status(err.code) is True
         else:
             assert False
 
     def _request_webpage(self, url_or_request, video_id, note=None, errnote=None, fatal=True, data=None, headers={}, query={}, expected_status=None):
         """
         Return the response handle.
 
         See _download_webpage docstring for arguments specification.
         """
         if note is None:
             self.report_download_webpage(video_id)
         elif note is not False:
             if video_id is None:
                 self.to_screen('%s' % (note,))
             else:
                 self.to_screen('%s: %s' % (video_id, note))
 
         # Some sites check X-Forwarded-For HTTP header in order to figure out
         # the origin of the client behind proxy. This allows bypassing geo
         # restriction by faking this header's value to IP that belongs to some
         # geo unrestricted country. We will do so once we encounter any
         # geo restriction error.
         if self._x_forwarded_for_ip:
             if 'X-Forwarded-For' not in headers:
                 headers['X-Forwarded-For'] = self._x_forwarded_for_ip
 
         if isinstance(url_or_request, compat_urllib_request.Request):
             url_or_request = update_Request(
                 url_or_request, data=data, headers=headers, query=query)
         else:
             if query:
                 url_or_request = update_url_query(url_or_request, query)
             if data is not None or headers:
                 url_or_request = sanitized_Request(url_or_request, data, headers)
         exceptions = [compat_urllib_error.URLError, compat_http_client.HTTPException, socket.error]
         if hasattr(ssl, 'CertificateError'):
             exceptions.append(ssl.CertificateError)
         try:
             return self._downloader.urlopen(url_or_request)
         except tuple(exceptions) as err:
             if isinstance(err, compat_urllib_error.HTTPError):
                 if self.__can_accept_status_code(err, expected_status):
                     # Retain reference to error to prevent file object from
                     # being closed before it can be read. Works around the
                     # effects of <https://bugs.python.org/issue15002>
                     # introduced in Python 3.4.1.
                     err.fp._error = err
                     return err.fp
 
             if errnote is False:
                 return False
             if errnote is None:
                 errnote = 'Unable to download webpage'
 
             errmsg = '%s: %s' % (errnote, error_to_compat_str(err))
             if fatal:
                 raise ExtractorError(errmsg, sys.exc_info()[2], cause=err)
             else:
                 self._downloader.report_warning(errmsg)
                 return False
 
     def _download_webpage_handle(self, url_or_request, video_id, note=None, errnote=None, fatal=True, encoding=None, data=None, headers={}, query={}, expected_status=None):
         """
         Return a tuple (page content as string, URL handle).
 
         See _download_webpage docstring for arguments specification.
         """
         # Strip hashes from the URL (#1038)
         if isinstance(url_or_request, (compat_str, str)):
             url_or_request = url_or_request.partition('#')[0]
 
         urlh = self._request_webpage(url_or_request, video_id, note, errnote, fatal, data=data, headers=headers, query=query, expected_status=expected_status)
         if urlh is False:
             assert not fatal
             return False
         content = self._webpage_read_content(urlh, url_or_request, video_id, note, errnote, fatal, encoding=encoding)
         return (content, urlh)
 
     @staticmethod
     def _guess_encoding_from_content(content_type, webpage_bytes):
         m = re.match(r'[a-zA-Z0-9_.-]+/[a-zA-Z0-9_.-]+\s*;\s*charset=(.+)', content_type)
         if m:
             encoding = m.group(1)
         else:
             m = re.search(br'<meta[^>]+charset=[\'"]?([^\'")]+)[ /\'">]',
                           webpage_bytes[:1024])
             if m:
                 encoding = m.group(1).decode('ascii')
             elif webpage_bytes.startswith(b'\xff\xfe'):
                 encoding = 'utf-16'
             else:
                 encoding = 'utf-8'
 
         return encoding
 
     def __check_blocked(self, content):
         first_block = content[:512]
         if ('<title>Access to this site is blocked</title>' in content
                 and 'Websense' in first_block):
             msg = 'Access to this webpage has been blocked by Websense filtering software in your network.'
             blocked_iframe = self._html_search_regex(
                 r'<iframe src="([^"]+)"', content,
                 'Websense information URL', default=None)
             if blocked_iframe:
                 msg += ' Visit %s for more details' % blocked_iframe
             raise ExtractorError(msg, expected=True)
         if '<title>The URL you requested has been blocked</title>' in first_block:
             msg = (
                 'Access to this webpage has been blocked by Indian censorship. '
                 'Use a VPN or proxy server (with --proxy) to route around it.')
             block_msg = self._html_search_regex(
                 r'</h1><p>(.*?)</p>',
                 content, 'block message', default=None)
             if block_msg:
                 msg += ' (Message: "%s")' % block_msg.replace('\n', ' ')
             raise ExtractorError(msg, expected=True)
         if ('<title>TTK :: Доступ к ресурсу ограничен</title>' in content
                 and 'blocklist.rkn.gov.ru' in content):
             raise ExtractorError(
                 'Access to this webpage has been blocked by decision of the Russian government. '
                 'Visit http://blocklist.rkn.gov.ru/ for a block reason.',
                 expected=True)
 
     def _webpage_read_content(self, urlh, url_or_request, video_id, note=None, errnote=None, fatal=True, prefix=None, encoding=None):
         content_type = urlh.headers.get('Content-Type', '')
         webpage_bytes = urlh.read()
         if prefix is not None:
             webpage_bytes = prefix + webpage_bytes
         if not encoding:
             encoding = self._guess_encoding_from_content(content_type, webpage_bytes)
         if self._downloader.params.get('dump_intermediate_pages', False):
             self.to_screen('Dumping request to ' + urlh.geturl())
             dump = base64.b64encode(webpage_bytes).decode('ascii')
             self._downloader.to_screen(dump)
         if self._downloader.params.get('write_pages', False):
             basen = '%s_%s' % (video_id, urlh.geturl())
             if len(basen) > 240:
                 h = '___' + hashlib.md5(basen.encode('utf-8')).hexdigest()
                 basen = basen[:240 - len(h)] + h
             raw_filename = basen + '.dump'
             filename = sanitize_filename(raw_filename, restricted=True)
             self.to_screen('Saving request to ' + filename)
             # Working around MAX_PATH limitation on Windows (see
             # http://msdn.microsoft.com/en-us/library/windows/desktop/aa365247(v=vs.85).aspx)
             if compat_os_name == 'nt':
                 absfilepath = os.path.abspath(filename)
                 if len(absfilepath) > 259:
                     filename = '\\\\?\\' + absfilepath
             with open(filename, 'wb') as outf:
                 outf.write(webpage_bytes)
 
         try:
             content = webpage_bytes.decode(encoding, 'replace')
         except LookupError:
             content = webpage_bytes.decode('utf-8', 'replace')
 
         self.__check_blocked(content)
 
         return content
 
     def _download_webpage(
             self, url_or_request, video_id, note=None, errnote=None,
             fatal=True, tries=1, timeout=5, encoding=None, data=None,
             headers={}, query={}, expected_status=None):
         """
         Return the data of the page as a string.
 
         Arguments:
         url_or_request -- plain text URL as a string or
             a compat_urllib_request.Requestobject
         video_id -- Video/playlist/item identifier (string)
 
         Keyword arguments:
         note -- note printed before downloading (string)
         errnote -- note printed in case of an error (string)
         fatal -- flag denoting whether error should be considered fatal,
             i.e. whether it should cause ExtractionError to be raised,
             otherwise a warning will be reported and extraction continued
         tries -- number of tries
         timeout -- sleep interval between tries
         encoding -- encoding for a page content decoding, guessed automatically
             when not explicitly specified
         data -- POST data (bytes)
         headers -- HTTP headers (dict)
         query -- URL query (dict)
         expected_status -- allows to accept failed HTTP requests (non 2xx
             status code) by explicitly specifying a set of accepted status
             codes. Can be any of the following entities:
                 - an integer type specifying an exact failed status code to
                   accept
                 - a list or a tuple of integer types specifying a list of
                   failed status codes to accept
                 - a callable accepting an actual failed status code and
                   returning True if it should be accepted
             Note that this argument does not affect success status codes (2xx)
             which are always accepted.
         """
 
         success = False
         try_count = 0
         while success is False:
             try:
                 res = self._download_webpage_handle(
                     url_or_request, video_id, note, errnote, fatal,
                     encoding=encoding, data=data, headers=headers, query=query,
                     expected_status=expected_status)
                 success = True
             except compat_http_client.IncompleteRead as e:
                 try_count += 1
                 if try_count >= tries:
                     raise e
                 self._sleep(timeout, video_id)
         if res is False:
             return res
         else:
             content, _ = res
             return content
 
     def _download_xml_handle(
             self, url_or_request, video_id, note='Downloading XML',
             errnote='Unable to download XML', transform_source=None,
             fatal=True, encoding=None, data=None, headers={}, query={},
             expected_status=None):
         """
         Return a tuple (xml as an compat_etree_Element, URL handle).
 
         See _download_webpage docstring for arguments specification.
         """
         res = self._download_webpage_handle(
             url_or_request, video_id, note, errnote, fatal=fatal,
             encoding=encoding, data=data, headers=headers, query=query,
             expected_status=expected_status)
         if res is False:
             return res
         xml_string, urlh = res
         return self._parse_xml(
             xml_string, video_id, transform_source=transform_source,
             fatal=fatal), urlh
 
     def _download_xml(
             self, url_or_request, video_id,
             note='Downloading XML', errnote='Unable to download XML',
             transform_source=None, fatal=True, encoding=None,
             data=None, headers={}, query={}, expected_status=None):
         """
         Return the xml as an compat_etree_Element.
 
         See _download_webpage docstring for arguments specification.
         """
         res = self._download_xml_handle(
             url_or_request, video_id, note=note, errnote=errnote,
             transform_source=transform_source, fatal=fatal, encoding=encoding,
             data=data, headers=headers, query=query,
             expected_status=expected_status)
         return res if res is False else res[0]
 
     def _parse_xml(self, xml_string, video_id, transform_source=None, fatal=True):
         if transform_source:
             xml_string = transform_source(xml_string)
         try:
             return compat_etree_fromstring(xml_string.encode('utf-8'))
         except compat_xml_parse_error as ve:
             errmsg = '%s: Failed to parse XML ' % video_id
             if fatal:
                 raise ExtractorError(errmsg, cause=ve)
             else:
                 self.report_warning(errmsg + str(ve))
 
     def _download_json_handle(
             self, url_or_request, video_id, note='Downloading JSON metadata',
             errnote='Unable to download JSON metadata', transform_source=None,
             fatal=True, encoding=None, data=None, headers={}, query={},
             expected_status=None):
         """
         Return a tuple (JSON object, URL handle).
 
         See _download_webpage docstring for arguments specification.
         """
         res = self._download_webpage_handle(
             url_or_request, video_id, note, errnote, fatal=fatal,
             encoding=encoding, data=data, headers=headers, query=query,
             expected_status=expected_status)
         if res is False:
             return res
         json_string, urlh = res
         return self._parse_json(
             json_string, video_id, transform_source=transform_source,
             fatal=fatal), urlh
 
     def _download_json(
             self, url_or_request, video_id, note='Downloading JSON metadata',
             errnote='Unable to download JSON metadata', transform_source=None,
             fatal=True, encoding=None, data=None, headers={}, query={},
             expected_status=None):
         """
         Return the JSON object as a dict.
 
         See _download_webpage docstring for arguments specification.
         """
         res = self._download_json_handle(
             url_or_request, video_id, note=note, errnote=errnote,
             transform_source=transform_source, fatal=fatal, encoding=encoding,
             data=data, headers=headers, query=query,
             expected_status=expected_status)
         return res if res is False else res[0]
 
     def _parse_json(self, json_string, video_id, transform_source=None, fatal=True):
         if transform_source:
             json_string = transform_source(json_string)
         try:
             return json.loads(json_string)
         except ValueError as ve:
             errmsg = '%s: Failed to parse JSON ' % video_id
             if fatal:
                 raise ExtractorError(errmsg, cause=ve)
             else:
                 self.report_warning(errmsg + str(ve))
 
     def report_warning(self, msg, video_id=None):
         idstr = '' if video_id is None else '%s: ' % video_id
         self._downloader.report_warning(
             '[%s] %s%s' % (self.IE_NAME, idstr, msg))
 
     def to_screen(self, msg):
         """Print msg to screen, prefixing it with '[ie_name]'"""
         self._downloader.to_screen('[%s] %s' % (self.IE_NAME, msg))
 
     def report_extraction(self, id_or_name):
         """Report information extraction."""
         self.to_screen('%s: Extracting information' % id_or_name)
 
     def report_download_webpage(self, video_id):
         """Report webpage download."""
         self.to_screen('%s: Downloading webpage' % video_id)
 
     def report_age_confirmation(self):
         """Report attempt to confirm age."""
         self.to_screen('Confirming age')
 
     def report_login(self):
         """Report attempt to log in."""
         self.to_screen('Logging in')
 
     @staticmethod
     def raise_login_required(msg='This video is only available for registered users'):
         raise ExtractorError(
             '%s. Use --username and --password or --netrc to provide account credentials.' % msg,
             expected=True)
 
     @staticmethod
     def raise_geo_restricted(msg='This video is not available from your location due to geo restriction', countries=None):
         raise GeoRestrictedError(msg, countries=countries)
 
     # Methods for following #608
     @staticmethod
     def url_result(url, ie=None, video_id=None, video_title=None):
         """Returns a URL that points to a page that should be processed"""
         # TODO: ie should be the class used for getting the info
         video_info = {'_type': 'url',
                       'url': url,
                       'ie_key': ie}
         if video_id is not None:
             video_info['id'] = video_id
         if video_title is not None:
             video_info['title'] = video_title
         return video_info
 
     def playlist_from_matches(self, matches, playlist_id=None, playlist_title=None, getter=None, ie=None):
         urls = orderedSet(
             self.url_result(self._proto_relative_url(getter(m) if getter else m), ie)
             for m in matches)
         return self.playlist_result(
             urls, playlist_id=playlist_id, playlist_title=playlist_title)
 
     @staticmethod
     def playlist_result(entries, playlist_id=None, playlist_title=None, playlist_description=None):
         """Returns a playlist"""
         video_info = {'_type': 'playlist',
                       'entries': entries}
         if playlist_id:
             video_info['id'] = playlist_id
         if playlist_title:
             video_info['title'] = playlist_title
         if playlist_description:
             video_info['description'] = playlist_description
         return video_info
 
     def _search_regex(self, pattern, string, name, default=NO_DEFAULT, fatal=True, flags=0, group=None):
         """
         Perform a regex search on the given string, using a single or a list of
         patterns returning the first matching group.
         In case of failure return a default value or raise a WARNING or a
         RegexNotFoundError, depending on fatal, specifying the field name.
         """
         if isinstance(pattern, (str, compat_str, compiled_regex_type)):
             mobj = re.search(pattern, string, flags)
         else:
             for p in pattern:
                 mobj = re.search(p, string, flags)
                 if mobj:
                     break
 
         if not self._downloader.params.get('no_color') and compat_os_name != 'nt' and sys.stderr.isatty():
             _name = '\033[0;34m%s\033[0m' % name
         else:
             _name = name
 
         if mobj:
             if group is None:
                 # return the first matching group
                 return next(g for g in mobj.groups() if g is not None)
             else:
                 return mobj.group(group)
         elif default is not NO_DEFAULT:
             return default
         elif fatal:
             raise RegexNotFoundError('Unable to extract %s' % _name)
         else:
             self._downloader.report_warning('unable to extract %s' % _name + bug_reports_message())
             return None
 
     def _html_search_regex(self, pattern, string, name, default=NO_DEFAULT, fatal=True, flags=0, group=None):
         """
         Like _search_regex, but strips HTML tags and unescapes entities.
         """
         res = self._search_regex(pattern, string, name, default, fatal, flags, group)
         if res:
             return clean_html(res).strip()
         else:
             return res
 
     def _get_netrc_login_info(self, netrc_machine=None):
         username = None
         password = None
         netrc_machine = netrc_machine or self._NETRC_MACHINE
 
         if self._downloader.params.get('usenetrc', False):
             try:
                 info = netrc.netrc().authenticators(netrc_machine)
                 if info is not None:
                     username = info[0]
                     password = info[2]
                 else:
                     raise netrc.NetrcParseError(
                         'No authenticators for %s' % netrc_machine)
             except (IOError, netrc.NetrcParseError) as err:
                 self._downloader.report_warning(
                     'parsing .netrc: %s' % error_to_compat_str(err))
 
         return username, password
 
     def _get_login_info(self, username_option='username', password_option='password', netrc_machine=None):
         """
         Get the login info as (username, password)
         First look for the manually specified credentials using username_option
         and password_option as keys in params dictionary. If no such credentials
         available look in the netrc file using the netrc_machine or _NETRC_MACHINE
         value.
         If there's no info available, return (None, None)
         """
         if self._downloader is None:
             return (None, None)
 
         downloader_params = self._downloader.params
 
         # Attempt to use provided username and password or .netrc data
         if downloader_params.get(username_option) is not None:
             username = downloader_params[username_option]
             password = downloader_params[password_option]
         else:
             username, password = self._get_netrc_login_info(netrc_machine)
 
         return username, password
 
     def _get_tfa_info(self, note='two-factor verification code'):
         """
         Get the two-factor authentication info
         TODO - asking the user will be required for sms/phone verify
         currently just uses the command line option
         If there's no info available, return None
         """
         if self._downloader is None:
             return None
         downloader_params = self._downloader.params
 
         if downloader_params.get('twofactor') is not None:
             return downloader_params['twofactor']
 
         return compat_getpass('Type %s and press [Return]: ' % note)
 
     # Helper functions for extracting OpenGraph info
     @staticmethod
     def _og_regexes(prop):
         content_re = r'content=(?:"([^"]+?)"|\'([^\']+?)\'|\s*([^\s"\'=<>`]+?))'
         property_re = (r'(?:name|property)=(?:\'og[:-]%(prop)s\'|"og[:-]%(prop)s"|\s*og[:-]%(prop)s\b)'
                        % {'prop': re.escape(prop)})
         template = r'<meta[^>]+?%s[^>]+?%s'
         return [
             template % (property_re, content_re),
             template % (content_re, property_re),
         ]
 
     @staticmethod
     def _meta_regex(prop):
         return r'''(?isx)<meta
                     (?=[^>]+(?:itemprop|name|property|id|http-equiv)=(["\']?)%s\1)
                     [^>]+?content=(["\'])(?P<content>.*?)\2''' % re.escape(prop)
 
     def _og_search_property(self, prop, html, name=None, **kargs):
         if not isinstance(prop, (list, tuple)):
             prop = [prop]
         if name is None:
             name = 'OpenGraph %s' % prop[0]
         og_regexes = []
         for p in prop:
             og_regexes.extend(self._og_regexes(p))
         escaped = self._search_regex(og_regexes, html, name, flags=re.DOTALL, **kargs)
         if escaped is None:
             return None
         return unescapeHTML(escaped)
 
     def _og_search_thumbnail(self, html, **kargs):
         return self._og_search_property('image', html, 'thumbnail URL', fatal=False, **kargs)
 
     def _og_search_description(self, html, **kargs):
         return self._og_search_property('description', html, fatal=False, **kargs)
 
     def _og_search_title(self, html, **kargs):
         return self._og_search_property('title', html, **kargs)
 
     def _og_search_video_url(self, html, name='video url', secure=True, **kargs):
         regexes = self._og_regexes('video') + self._og_regexes('video:url')
         if secure:
             regexes = self._og_regexes('video:secure_url') + regexes
         return self._html_search_regex(regexes, html, name, **kargs)
 
     def _og_search_url(self, html, **kargs):
         return self._og_search_property('url', html, **kargs)
 
     def _html_search_meta(self, name, html, display_name=None, fatal=False, **kwargs):
         if not isinstance(name, (list, tuple)):
             name = [name]
         if display_name is None:
             display_name = name[0]
         return self._html_search_regex(
             [self._meta_regex(n) for n in name],
             html, display_name, fatal=fatal, group='content', **kwargs)
 
     def _dc_search_uploader(self, html):
         return self._html_search_meta('dc.creator', html, 'uploader')
 
     def _rta_search(self, html):
         # See http://www.rtalabel.org/index.php?content=howtofaq#single
         if re.search(r'(?ix)<meta\s+name="rating"\s+'
                      r'     content="RTA-5042-1996-1400-1577-RTA"',
                      html):
             return 18
         return 0
 
     def _media_rating_search(self, html):
         # See http://www.tjg-designs.com/WP/metadata-code-examples-adding-metadata-to-your-web-pages/
         rating = self._html_search_meta('rating', html)
 
         if not rating:
             return None
 
         RATING_TABLE = {
             'safe for kids': 0,
             'general': 8,
             '14 years': 14,
             'mature': 17,
             'restricted': 19,
         }
         return RATING_TABLE.get(rating.lower())
 
     def _family_friendly_search(self, html):
         # See http://schema.org/VideoObject
         family_friendly = self._html_search_meta(
             'isFamilyFriendly', html, default=None)
 
         if not family_friendly:
             return None
 
         RATING_TABLE = {
             '1': 0,
             'true': 0,
             '0': 18,
             'false': 18,
         }
         return RATING_TABLE.get(family_friendly.lower())
 
     def _twitter_search_player(self, html):
         return self._html_search_meta('twitter:player', html,
                                       'twitter card player')
 
     def _search_json_ld(self, html, video_id, expected_type=None, **kwargs):
         json_ld_list = list(re.finditer(JSON_LD_RE, html))
         default = kwargs.get('default', NO_DEFAULT)
         # JSON-LD may be malformed and thus `fatal` should be respected.
         # At the same time `default` may be passed that assumes `fatal=False`
         # for _search_regex. Let's simulate the same behavior here as well.
         fatal = kwargs.get('fatal', True) if default == NO_DEFAULT else False
         json_ld = []
         for mobj in json_ld_list:
             json_ld_item = self._parse_json(
                 mobj.group('json_ld'), video_id, fatal=fatal)
             if not json_ld_item:
                 continue
             if isinstance(json_ld_item, dict):
                 json_ld.append(json_ld_item)
             elif isinstance(json_ld_item, (list, tuple)):
                 json_ld.extend(json_ld_item)
         if json_ld:
             json_ld = self._json_ld(json_ld, video_id, fatal=fatal, expected_type=expected_type)
         if json_ld:
             return json_ld
         if default is not NO_DEFAULT:
             return default
         elif fatal:
             raise RegexNotFoundError('Unable to extract JSON-LD')
         else:
             self._downloader.report_warning('unable to extract JSON-LD %s' % bug_reports_message())
             return {}
 
     def _json_ld(self, json_ld, video_id, fatal=True, expected_type=None):
         if isinstance(json_ld, compat_str):
             json_ld = self._parse_json(json_ld, video_id, fatal=fatal)
         if not json_ld:
             return {}
         info = {}
         if not isinstance(json_ld, (list, tuple, dict)):
             return info
         if isinstance(json_ld, dict):
             json_ld = [json_ld]
 
         INTERACTION_TYPE_MAP = {
             'CommentAction': 'comment',
             'AgreeAction': 'like',
             'DisagreeAction': 'dislike',
             'LikeAction': 'like',
             'DislikeAction': 'dislike',
             'ListenAction': 'view',
             'WatchAction': 'view',
             'ViewAction': 'view',
         }
 
         def extract_interaction_type(e):
             interaction_type = e.get('interactionType')
             if isinstance(interaction_type, dict):
                 interaction_type = interaction_type.get('@type')
             return str_or_none(interaction_type)
 
         def extract_interaction_statistic(e):
             interaction_statistic = e.get('interactionStatistic')
             if isinstance(interaction_statistic, dict):
                 interaction_statistic = [interaction_statistic]
             if not isinstance(interaction_statistic, list):
                 return
             for is_e in interaction_statistic:
                 if not isinstance(is_e, dict):
                     continue
                 if is_e.get('@type') != 'InteractionCounter':
                     continue
                 interaction_type = extract_interaction_type(is_e)
                 if not interaction_type:
                     continue
                 # For interaction count some sites provide string instead of
                 # an integer (as per spec) with non digit characters (e.g. ",")
                 # so extracting count with more relaxed str_to_int
                 interaction_count = str_to_int(is_e.get('userInteractionCount'))
                 if interaction_count is None:
                     continue
                 count_kind = INTERACTION_TYPE_MAP.get(interaction_type.split('/')[-1])
                 if not count_kind:
                     continue
                 count_key = '%s_count' % count_kind
                 if info.get(count_key) is not None:
                     continue
                 info[count_key] = interaction_count
 
         def extract_video_object(e):
             assert e['@type'] == 'VideoObject'
             author = e.get('author')
             info.update({
                 'url': url_or_none(e.get('contentUrl')),
                 'title': unescapeHTML(e.get('name')),
                 'description': unescapeHTML(e.get('description')),
                 'thumbnail': url_or_none(e.get('thumbnailUrl') or e.get('thumbnailURL')),
                 'duration': parse_duration(e.get('duration')),
                 'timestamp': unified_timestamp(e.get('uploadDate')),
                 # author can be an instance of 'Organization' or 'Person' types.
                 # both types can have 'name' property(inherited from 'Thing' type). [1]
                 # however some websites are using 'Text' type instead.
                 # 1. https://schema.org/VideoObject
                 'uploader': author.get('name') if isinstance(author, dict) else author if isinstance(author, compat_str) else None,
                 'filesize': float_or_none(e.get('contentSize')),
                 'tbr': int_or_none(e.get('bitrate')),
                 'width': int_or_none(e.get('width')),
                 'height': int_or_none(e.get('height')),
                 'view_count': int_or_none(e.get('interactionCount')),
             })
             extract_interaction_statistic(e)
 
         for e in json_ld:
             if '@context' in e:
                 item_type = e.get('@type')
                 if expected_type is not None and expected_type != item_type:
                     continue
                 if item_type in ('TVEpisode', 'Episode'):
                     episode_name = unescapeHTML(e.get('name'))
                     info.update({
                         'episode': episode_name,
                         'episode_number': int_or_none(e.get('episodeNumber')),
                         'description': unescapeHTML(e.get('description')),
                     })
                     if not info.get('title') and episode_name:
                         info['title'] = episode_name
                     part_of_season = e.get('partOfSeason')
                     if isinstance(part_of_season, dict) and part_of_season.get('@type') in ('TVSeason', 'Season', 'CreativeWorkSeason'):
                         info.update({
                             'season': unescapeHTML(part_of_season.get('name')),
                             'season_number': int_or_none(part_of_season.get('seasonNumber')),
                         })
                     part_of_series = e.get('partOfSeries') or e.get('partOfTVSeries')
                     if isinstance(part_of_series, dict) and part_of_series.get('@type') in ('TVSeries', 'Series', 'CreativeWorkSeries'):
                         info['series'] = unescapeHTML(part_of_series.get('name'))
                 elif item_type == 'Movie':
                     info.update({
                         'title': unescapeHTML(e.get('name')),
                         'description': unescapeHTML(e.get('description')),
                         'duration': parse_duration(e.get('duration')),
                         'timestamp': unified_timestamp(e.get('dateCreated')),
                     })
                 elif item_type in ('Article', 'NewsArticle'):
                     info.update({
                         'timestamp': parse_iso8601(e.get('datePublished')),
                         'title': unescapeHTML(e.get('headline')),
                         'description': unescapeHTML(e.get('articleBody')),
                     })
                 elif item_type == 'VideoObject':
                     extract_video_object(e)
                     if expected_type is None:
                         continue
                     else:
                         break
                 video = e.get('video')
                 if isinstance(video, dict) and video.get('@type') == 'VideoObject':
                     extract_video_object(video)
                 if expected_type is None:
                     continue
                 else:
                     break
         return dict((k, v) for k, v in info.items() if v is not None)
 
     @staticmethod
     def _hidden_inputs(html):
         html = re.sub(r'<!--(?:(?!<!--).)*-->', '', html)
         hidden_inputs = {}
         for input in re.findall(r'(?i)(<input[^>]+>)', html):
             attrs = extract_attributes(input)
             if not input:
                 continue
             if attrs.get('type') not in ('hidden', 'submit'):
                 continue
             name = attrs.get('name') or attrs.get('id')
             value = attrs.get('value')
             if name and value is not None:
                 hidden_inputs[name] = value
         return hidden_inputs
 
     def _form_hidden_inputs(self, form_id, html):
         form = self._search_regex(
             r'(?is)<form[^>]+?id=(["\'])%s\1[^>]*>(?P<form>.+?)</form>' % form_id,
             html, '%s form' % form_id, group='form')
         return self._hidden_inputs(form)
 
     def _sort_formats(self, formats, field_preference=None):
         if not formats:
             raise ExtractorError('No video formats found')
 
         for f in formats:
             # Automatically determine tbr when missing based on abr and vbr (improves
             # formats sorting in some cases)
             if 'tbr' not in f and f.get('abr') is not None and f.get('vbr') is not None:
                 f['tbr'] = f['abr'] + f['vbr']
 
         def _formats_key(f):
             # TODO remove the following workaround
             from ..utils import determine_ext
             if not f.get('ext') and 'url' in f:
                 f['ext'] = determine_ext(f['url'])
 
             if isinstance(field_preference, (list, tuple)):
                 return tuple(
                     f.get(field)
                     if f.get(field) is not None
                     else ('' if field == 'format_id' else -1)
                     for field in field_preference)
 
             preference = f.get('preference')
             if preference is None:
                 preference = 0
                 if f.get('ext') in ['f4f', 'f4m']:  # Not yet supported
                     preference -= 0.5
 
             protocol = f.get('protocol') or determine_protocol(f)
             proto_preference = 0 if protocol in ['http', 'https'] else (-0.5 if protocol == 'rtsp' else -0.1)
 
             if f.get('vcodec') == 'none':  # audio only
                 preference -= 50
                 if self._downloader.params.get('prefer_free_formats'):
                     ORDER = ['aac', 'mp3', 'm4a', 'webm', 'ogg', 'opus']
                 else:
                     ORDER = ['webm', 'opus', 'ogg', 'mp3', 'aac', 'm4a']
                 ext_preference = 0
                 try:
                     audio_ext_preference = ORDER.index(f['ext'])
                 except ValueError:
                     audio_ext_preference = -1
             else:
                 if f.get('acodec') == 'none':  # video only
                     preference -= 40
                 if self._downloader.params.get('prefer_free_formats'):
                     ORDER = ['flv', 'mp4', 'webm']
                 else:
                     ORDER = ['webm', 'flv', 'mp4']
                 try:
                     ext_preference = ORDER.index(f['ext'])
                 except ValueError:
                     ext_preference = -1
                 audio_ext_preference = 0
 
             return (
                 preference,
                 f.get('language_preference') if f.get('language_preference') is not None else -1,
                 f.get('quality') if f.get('quality') is not None else -1,
                 f.get('tbr') if f.get('tbr') is not None else -1,
                 f.get('filesize') if f.get('filesize') is not None else -1,
                 f.get('vbr') if f.get('vbr') is not None else -1,
                 f.get('height') if f.get('height') is not None else -1,
                 f.get('width') if f.get('width') is not None else -1,
                 proto_preference,
                 ext_preference,
                 f.get('abr') if f.get('abr') is not None else -1,
                 audio_ext_preference,
                 f.get('fps') if f.get('fps') is not None else -1,
                 f.get('filesize_approx') if f.get('filesize_approx') is not None else -1,
                 f.get('source_preference') if f.get('source_preference') is not None else -1,
                 f.get('format_id') if f.get('format_id') is not None else '',
             )
         formats.sort(key=_formats_key)
 
     def _check_formats(self, formats, video_id):
         if formats:
             formats[:] = filter(
                 lambda f: self._is_valid_url(
                     f['url'], video_id,
                     item='%s video format' % f.get('format_id') if f.get('format_id') else 'video'),
                 formats)
 
     @staticmethod
     def _remove_duplicate_formats(formats):
         format_urls = set()
         unique_formats = []
         for f in formats:
             if f['url'] not in format_urls:
                 format_urls.add(f['url'])
                 unique_formats.append(f)
         formats[:] = unique_formats
 
     def _is_valid_url(self, url, video_id, item='video', headers={}):
         url = self._proto_relative_url(url, scheme='http:')
         # For now assume non HTTP(S) URLs always valid
         if not (url.startswith('http://') or url.startswith('https://')):
             return True
         try:
             self._request_webpage(url, video_id, 'Checking %s URL' % item, headers=headers)
             return True
         except ExtractorError as e:
             self.to_screen(
                 '%s: %s URL is invalid, skipping: %s'
                 % (video_id, item, error_to_compat_str(e.cause)))
             return False
 
     def http_scheme(self):
         """ Either "http:" or "https:", depending on the user's preferences """
         return (
             'http:'
             if self._downloader.params.get('prefer_insecure', False)
             else 'https:')
 
     def _proto_relative_url(self, url, scheme=None):
         if url is None:
             return url
         if url.startswith('//'):
             if scheme is None:
                 scheme = self.http_scheme()
             return scheme + url
         else:
             return url
 
     def _sleep(self, timeout, video_id, msg_template=None):
         if msg_template is None:
             msg_template = '%(video_id)s: Waiting for %(timeout)s seconds'
         msg = msg_template % {'video_id': video_id, 'timeout': timeout}
         self.to_screen(msg)
         time.sleep(timeout)
 
     def _extract_f4m_formats(self, manifest_url, video_id, preference=None, f4m_id=None,
                              transform_source=lambda s: fix_xml_ampersands(s).strip(),
                              fatal=True, m3u8_id=None, data=None, headers={}, query={}):
         manifest = self._download_xml(
             manifest_url, video_id, 'Downloading f4m manifest',
             'Unable to download f4m manifest',
             # Some manifests may be malformed, e.g. prosiebensat1 generated manifests
             # (see https://github.com/ytdl-org/youtube-dl/issues/6215#issuecomment-121704244)
             transform_source=transform_source,
             fatal=fatal, data=data, headers=headers, query=query)
 
         if manifest is False:
             return []
 
         return self._parse_f4m_formats(
             manifest, manifest_url, video_id, preference=preference, f4m_id=f4m_id,
             transform_source=transform_source, fatal=fatal, m3u8_id=m3u8_id)
 
     def _parse_f4m_formats(self, manifest, manifest_url, video_id, preference=None, f4m_id=None,
                            transform_source=lambda s: fix_xml_ampersands(s).strip(),
                            fatal=True, m3u8_id=None):
         if not isinstance(manifest, compat_etree_Element) and not fatal:
             return []
 
         # currently youtube-dl cannot decode the playerVerificationChallenge as Akamai uses Adobe Alchemy
         akamai_pv = manifest.find('{http://ns.adobe.com/f4m/1.0}pv-2.0')
         if akamai_pv is not None and ';' in akamai_pv.text:
             playerVerificationChallenge = akamai_pv.text.split(';')[0]
             if playerVerificationChallenge.strip() != '':
                 return []
 
         formats = []
         manifest_version = '1.0'
         media_nodes = manifest.findall('{http://ns.adobe.com/f4m/1.0}media')
         if not media_nodes:
             manifest_version = '2.0'
             media_nodes = manifest.findall('{http://ns.adobe.com/f4m/2.0}media')
         # Remove unsupported DRM protected media from final formats
         # rendition (see https://github.com/ytdl-org/youtube-dl/issues/8573).
         media_nodes = remove_encrypted_media(media_nodes)
         if not media_nodes:
             return formats
 
         manifest_base_url = get_base_url(manifest)
 
         bootstrap_info = xpath_element(
             manifest, ['{http://ns.adobe.com/f4m/1.0}bootstrapInfo', '{http://ns.adobe.com/f4m/2.0}bootstrapInfo'],
             'bootstrap info', default=None)
 
         vcodec = None
         mime_type = xpath_text(
             manifest, ['{http://ns.adobe.com/f4m/1.0}mimeType', '{http://ns.adobe.com/f4m/2.0}mimeType'],
             'base URL', default=None)
         if mime_type and mime_type.startswith('audio/'):
             vcodec = 'none'
 
         for i, media_el in enumerate(media_nodes):
             tbr = int_or_none(media_el.attrib.get('bitrate'))
             width = int_or_none(media_el.attrib.get('width'))
             height = int_or_none(media_el.attrib.get('height'))
             format_id = '-'.join(filter(None, [f4m_id, compat_str(i if tbr is None else tbr)]))
             # If <bootstrapInfo> is present, the specified f4m is a
             # stream-level manifest, and only set-level manifests may refer to
             # external resources.  See section 11.4 and section 4 of F4M spec
             if bootstrap_info is None:
                 media_url = None
                 # @href is introduced in 2.0, see section 11.6 of F4M spec
                 if manifest_version == '2.0':
                     media_url = media_el.attrib.get('href')
                 if media_url is None:
                     media_url = media_el.attrib.get('url')
                 if not media_url:
                     continue
                 manifest_url = (
                     media_url if media_url.startswith('http://') or media_url.startswith('https://')
                     else ((manifest_base_url or '/'.join(manifest_url.split('/')[:-1])) + '/' + media_url))
                 # If media_url is itself a f4m manifest do the recursive extraction
                 # since bitrates in parent manifest (this one) and media_url manifest
                 # may differ leading to inability to resolve the format by requested
                 # bitrate in f4m downloader
                 ext = determine_ext(manifest_url)
                 if ext == 'f4m':
                     f4m_formats = self._extract_f4m_formats(
                         manifest_url, video_id, preference=preference, f4m_id=f4m_id,
                         transform_source=transform_source, fatal=fatal)
                     # Sometimes stream-level manifest contains single media entry that
                     # does not contain any quality metadata (e.g. http://matchtv.ru/#live-player).
                     # At the same time parent's media entry in set-level manifest may
                     # contain it. We will copy it from parent in such cases.
                     if len(f4m_formats) == 1:
                         f = f4m_formats[0]
                         f.update({
                             'tbr': f.get('tbr') or tbr,
                             'width': f.get('width') or width,
                             'height': f.get('height') or height,
                             'format_id': f.get('format_id') if not tbr else format_id,
                             'vcodec': vcodec,
                         })
                     formats.extend(f4m_formats)
                     continue
                 elif ext == 'm3u8':
                     formats.extend(self._extract_m3u8_formats(
                         manifest_url, video_id, 'mp4', preference=preference,
                         m3u8_id=m3u8_id, fatal=fatal))
                     continue
             formats.append({
                 'format_id': format_id,
                 'url': manifest_url,
                 'manifest_url': manifest_url,
                 'ext': 'flv' if bootstrap_info is not None else None,
                 'protocol': 'f4m',
                 'tbr': tbr,
                 'width': width,
                 'height': height,
                 'vcodec': vcodec,
                 'preference': preference,
             })
         return formats
 
     def _m3u8_meta_format(self, m3u8_url, ext=None, preference=None, m3u8_id=None):
         return {
             'format_id': '-'.join(filter(None, [m3u8_id, 'meta'])),
             'url': m3u8_url,
             'ext': ext,
             'protocol': 'm3u8',
             'preference': preference - 100 if preference else -100,
             'resolution': 'multiple',
             'format_note': 'Quality selection URL',
         }
 
     def _extract_m3u8_formats(self, m3u8_url, video_id, ext=None,
                               entry_protocol='m3u8', preference=None,
                               m3u8_id=None, note=None, errnote=None,
                               fatal=True, live=False, data=None, headers={},
                               query={}):
         res = self._download_webpage_handle(
             m3u8_url, video_id,
             note=note or 'Downloading m3u8 information',
             errnote=errnote or 'Failed to download m3u8 information',
             fatal=fatal, data=data, headers=headers, query=query)
 
         if res is False:
             return []
 
         m3u8_doc, urlh = res
         m3u8_url = urlh.geturl()
 
         return self._parse_m3u8_formats(
             m3u8_doc, m3u8_url, ext=ext, entry_protocol=entry_protocol,
             preference=preference, m3u8_id=m3u8_id, live=live)
 
     def _parse_m3u8_formats(self, m3u8_doc, m3u8_url, ext=None,
                             entry_protocol='m3u8', preference=None,
                             m3u8_id=None, live=False):
         if '#EXT-X-FAXS-CM:' in m3u8_doc:  # Adobe Flash Access
             return []
 
         if re.search(r'#EXT-X-SESSION-KEY:.*?URI="skd://', m3u8_doc):  # Apple FairPlay
             return []
 
         formats = []
 
         format_url = lambda u: (
             u
             if re.match(r'^https?://', u)
             else compat_urlparse.urljoin(m3u8_url, u))
 
         # References:
         # 1. https://tools.ietf.org/html/draft-pantos-http-live-streaming-21
         # 2. https://github.com/ytdl-org/youtube-dl/issues/12211
         # 3. https://github.com/ytdl-org/youtube-dl/issues/18923
 
         # We should try extracting formats only from master playlists [1, 4.3.4],
         # i.e. playlists that describe available qualities. On the other hand
         # media playlists [1, 4.3.3] should be returned as is since they contain
         # just the media without qualities renditions.
         # Fortunately, master playlist can be easily distinguished from media
         # playlist based on particular tags availability. As of [1, 4.3.3, 4.3.4]
         # master playlist tags MUST NOT appear in a media playlist and vice versa.
         # As of [1, 4.3.3.1] #EXT-X-TARGETDURATION tag is REQUIRED for every
         # media playlist and MUST NOT appear in master playlist thus we can
         # clearly detect media playlist with this criterion.
 
         if '#EXT-X-TARGETDURATION' in m3u8_doc:  # media playlist, return as is
             return [{
                 'url': m3u8_url,
                 'format_id': m3u8_id,
                 'ext': ext,
                 'protocol': entry_protocol,
                 'preference': preference,
             }]
 
         groups = {}
         last_stream_inf = {}
 
         def extract_media(x_media_line):
             media = parse_m3u8_attributes(x_media_line)
             # As per [1, 4.3.4.1] TYPE, GROUP-ID and NAME are REQUIRED
             media_type, group_id, name = media.get('TYPE'), media.get('GROUP-ID'), media.get('NAME')
             if not (media_type and group_id and name):
                 return
             groups.setdefault(group_id, []).append(media)
             if media_type not in ('VIDEO', 'AUDIO'):
                 return
             media_url = media.get('URI')
             if media_url:
                 format_id = []
                 for v in (m3u8_id, group_id, name):
                     if v:
                         format_id.append(v)
                 f = {
                     'format_id': '-'.join(format_id),
                     'url': format_url(media_url),
                     'manifest_url': m3u8_url,
                     'language': media.get('LANGUAGE'),
                     'ext': ext,
                     'protocol': entry_protocol,
                     'preference': preference,
                 }
                 if media_type == 'AUDIO':
                     f['vcodec'] = 'none'
                 formats.append(f)
 
         def build_stream_name():
             # Despite specification does not mention NAME attribute for
             # EXT-X-STREAM-INF tag it still sometimes may be present (see [1]
             # or vidio test in TestInfoExtractor.test_parse_m3u8_formats)
             # 1. http://www.vidio.com/watch/165683-dj_ambred-booyah-live-2015
             stream_name = last_stream_inf.get('NAME')
             if stream_name:
                 return stream_name
             # If there is no NAME in EXT-X-STREAM-INF it will be obtained
             # from corresponding rendition group
             stream_group_id = last_stream_inf.get('VIDEO')
             if not stream_group_id:
                 return
             stream_group = groups.get(stream_group_id)
             if not stream_group:
                 return stream_group_id
             rendition = stream_group[0]
             return rendition.get('NAME') or stream_group_id
 
         # parse EXT-X-MEDIA tags before EXT-X-STREAM-INF in order to have the
         # chance to detect video only formats when EXT-X-STREAM-INF tags
         # precede EXT-X-MEDIA tags in HLS manifest such as [3].
         for line in m3u8_doc.splitlines():
             if line.startswith('#EXT-X-MEDIA:'):
                 extract_media(line)
 
         for line in m3u8_doc.splitlines():
             if line.startswith('#EXT-X-STREAM-INF:'):
                 last_stream_inf = parse_m3u8_attributes(line)
             elif line.startswith('#') or not line.strip():
                 continue
             else:
                 tbr = float_or_none(
                     last_stream_inf.get('AVERAGE-BANDWIDTH')
                     or last_stream_inf.get('BANDWIDTH'), scale=1000)
                 format_id = []
                 if m3u8_id:
                     format_id.append(m3u8_id)
                 stream_name = build_stream_name()
                 # Bandwidth of live streams may differ over time thus making
                 # format_id unpredictable. So it's better to keep provided
                 # format_id intact.
                 if not live:
                     format_id.append(stream_name if stream_name else '%d' % (tbr if tbr else len(formats)))
                 manifest_url = format_url(line.strip())
                 f = {
                     'format_id': '-'.join(format_id),
                     'url': manifest_url,
                     'manifest_url': m3u8_url,
                     'tbr': tbr,
                     'ext': ext,
                     'fps': float_or_none(last_stream_inf.get('FRAME-RATE')),
                     'protocol': entry_protocol,
                     'preference': preference,
                 }
                 resolution = last_stream_inf.get('RESOLUTION')
                 if resolution:
                     mobj = re.search(r'(?P<width>\d+)[xX](?P<height>\d+)', resolution)
                     if mobj:
                         f['width'] = int(mobj.group('width'))
                         f['height'] = int(mobj.group('height'))
                 # Unified Streaming Platform
                 mobj = re.search(
                     r'audio.*?(?:%3D|=)(\d+)(?:-video.*?(?:%3D|=)(\d+))?', f['url'])
                 if mobj:
                     abr, vbr = mobj.groups()
                     abr, vbr = float_or_none(abr, 1000), float_or_none(vbr, 1000)
                     f.update({
                         'vbr': vbr,
                         'abr': abr,
                     })
                 codecs = parse_codecs(last_stream_inf.get('CODECS'))
                 f.update(codecs)
                 audio_group_id = last_stream_inf.get('AUDIO')
                 # As per [1, 4.3.4.1.1] any EXT-X-STREAM-INF tag which
                 # references a rendition group MUST have a CODECS attribute.
                 # However, this is not always respected, for example, [2]
                 # contains EXT-X-STREAM-INF tag which references AUDIO
                 # rendition group but does not have CODECS and despite
                 # referencing an audio group it represents a complete
                 # (with audio and video) format. So, for such cases we will
                 # ignore references to rendition groups and treat them
                 # as complete formats.
                 if audio_group_id and codecs and f.get('vcodec') != 'none':
                     audio_group = groups.get(audio_group_id)
                     if audio_group and audio_group[0].get('URI'):
                         # TODO: update acodec for audio only formats with
                         # the same GROUP-ID
                         f['acodec'] = 'none'
                 formats.append(f)
 
                 # for DailyMotion
                 progressive_uri = last_stream_inf.get('PROGRESSIVE-URI')
                 if progressive_uri:
                     http_f = f.copy()
                     del http_f['manifest_url']
                     http_f.update({
                         'format_id': f['format_id'].replace('hls-', 'http-'),
                         'protocol': 'http',
                         'url': progressive_uri,
                     })
                     formats.append(http_f)
 
                 last_stream_inf = {}
         return formats
 
     @staticmethod
     def _xpath_ns(path, namespace=None):
         if not namespace:
             return path
         out = []
         for c in path.split('/'):
             if not c or c == '.':
                 out.append(c)
             else:
                 out.append('{%s}%s' % (namespace, c))
         return '/'.join(out)
 
     def _extract_smil_formats(self, smil_url, video_id, fatal=True, f4m_params=None, transform_source=None):
         smil = self._download_smil(smil_url, video_id, fatal=fatal, transform_source=transform_source)
 
         if smil is False:
             assert not fatal
             return []
 
         namespace = self._parse_smil_namespace(smil)
 
         return self._parse_smil_formats(
             smil, smil_url, video_id, namespace=namespace, f4m_params=f4m_params)
 
     def _extract_smil_info(self, smil_url, video_id, fatal=True, f4m_params=None):
         smil = self._download_smil(smil_url, video_id, fatal=fatal)
         if smil is False:
             return {}
         return self._parse_smil(smil, smil_url, video_id, f4m_params=f4m_params)
 
     def _download_smil(self, smil_url, video_id, fatal=True, transform_source=None):
         return self._download_xml(
             smil_url, video_id, 'Downloading SMIL file',
             'Unable to download SMIL file', fatal=fatal, transform_source=transform_source)
 
     def _parse_smil(self, smil, smil_url, video_id, f4m_params=None):
         namespace = self._parse_smil_namespace(smil)
 
         formats = self._parse_smil_formats(
             smil, smil_url, video_id, namespace=namespace, f4m_params=f4m_params)
         subtitles = self._parse_smil_subtitles(smil, namespace=namespace)
 
         video_id = os.path.splitext(url_basename(smil_url))[0]
         title = None
         description = None
         upload_date = None
         for meta in smil.findall(self._xpath_ns('./head/meta', namespace)):
             name = meta.attrib.get('name')
             content = meta.attrib.get('content')
             if not name or not content:
                 continue
             if not title and name == 'title':
                 title = content
             elif not description and name in ('description', 'abstract'):
                 description = content
             elif not upload_date and name == 'date':
                 upload_date = unified_strdate(content)
 
         thumbnails = [{
             'id': image.get('type'),
             'url': image.get('src'),
             'width': int_or_none(image.get('width')),
             'height': int_or_none(image.get('height')),
         } for image in smil.findall(self._xpath_ns('.//image', namespace)) if image.get('src')]
 
         return {
             'id': video_id,
             'title': title or video_id,
             'description': description,
             'upload_date': upload_date,
             'thumbnails': thumbnails,
             'formats': formats,
             'subtitles': subtitles,
         }
 
     def _parse_smil_namespace(self, smil):
         return self._search_regex(
             r'(?i)^{([^}]+)?}smil$', smil.tag, 'namespace', default=None)
 
     def _parse_smil_formats(self, smil, smil_url, video_id, namespace=None, f4m_params=None, transform_rtmp_url=None):
         base = smil_url
         for meta in smil.findall(self._xpath_ns('./head/meta', namespace)):
             b = meta.get('base') or meta.get('httpBase')
             if b:
                 base = b
                 break
 
         formats = []
         rtmp_count = 0
         http_count = 0
         m3u8_count = 0
 
         srcs = []
         media = smil.findall(self._xpath_ns('.//video', namespace)) + smil.findall(self._xpath_ns('.//audio', namespace))
         for medium in media:
             src = medium.get('src')
             if not src or src in srcs:
                 continue
             srcs.append(src)
 
             bitrate = float_or_none(medium.get('system-bitrate') or medium.get('systemBitrate'), 1000)
             filesize = int_or_none(medium.get('size') or medium.get('fileSize'))
             width = int_or_none(medium.get('width'))
             height = int_or_none(medium.get('height'))
             proto = medium.get('proto')
             ext = medium.get('ext')
             src_ext = determine_ext(src)
             streamer = medium.get('streamer') or base
 
             if proto == 'rtmp' or streamer.startswith('rtmp'):
                 rtmp_count += 1
                 formats.append({
                     'url': streamer,
                     'play_path': src,
                     'ext': 'flv',
                     'format_id': 'rtmp-%d' % (rtmp_count if bitrate is None else bitrate),
                     'tbr': bitrate,
                     'filesize': filesize,
                     'width': width,
                     'height': height,
                 })
                 if transform_rtmp_url:
                     streamer, src = transform_rtmp_url(streamer, src)
                     formats[-1].update({
                         'url': streamer,
                         'play_path': src,
                     })
                 continue
 
             src_url = src if src.startswith('http') else compat_urlparse.urljoin(base, src)
             src_url = src_url.strip()
 
             if proto == 'm3u8' or src_ext == 'm3u8':
                 m3u8_formats = self._extract_m3u8_formats(
                     src_url, video_id, ext or 'mp4', m3u8_id='hls', fatal=False)
                 if len(m3u8_formats) == 1:
                     m3u8_count += 1
                     m3u8_formats[0].update({
                         'format_id': 'hls-%d' % (m3u8_count if bitrate is None else bitrate),
                         'tbr': bitrate,
                         'width': width,
                         'height': height,
                     })
                 formats.extend(m3u8_formats)
             elif src_ext == 'f4m':
                 f4m_url = src_url
                 if not f4m_params:
                     f4m_params = {
                         'hdcore': '3.2.0',
                         'plugin': 'flowplayer-3.2.0.1',
                     }
                 f4m_url += '&' if '?' in f4m_url else '?'
                 f4m_url += compat_urllib_parse_urlencode(f4m_params)
                 formats.extend(self._extract_f4m_formats(f4m_url, video_id, f4m_id='hds', fatal=False))
             elif src_ext == 'mpd':
                 formats.extend(self._extract_mpd_formats(
                     src_url, video_id, mpd_id='dash', fatal=False))
             elif re.search(r'\.ism/[Mm]anifest', src_url):
                 formats.extend(self._extract_ism_formats(
                     src_url, video_id, ism_id='mss', fatal=False))
             elif src_url.startswith('http') and self._is_valid_url(src, video_id):
                 http_count += 1
                 formats.append({
                     'url': src_url,
                     'ext': ext or src_ext or 'flv',
                     'format_id': 'http-%d' % (bitrate or http_count),
                     'tbr': bitrate,
                     'filesize': filesize,
                     'width': width,
                     'height': height,
                 })
 
         return formats
 
     def _parse_smil_subtitles(self, smil, namespace=None, subtitles_lang='en'):
         urls = []
         subtitles = {}
         for num, textstream in enumerate(smil.findall(self._xpath_ns('.//textstream', namespace))):
             src = textstream.get('src')
             if not src or src in urls:
                 continue
             urls.append(src)
             ext = textstream.get('ext') or mimetype2ext(textstream.get('type')) or determine_ext(src)
             lang = textstream.get('systemLanguage') or textstream.get('systemLanguageName') or textstream.get('lang') or subtitles_lang
             subtitles.setdefault(lang, []).append({
                 'url': src,
                 'ext': ext,
             })
         return subtitles
 
     def _extract_xspf_playlist(self, xspf_url, playlist_id, fatal=True):
         xspf = self._download_xml(
             xspf_url, playlist_id, 'Downloading xpsf playlist',
             'Unable to download xspf manifest', fatal=fatal)
         if xspf is False:
             return []
         return self._parse_xspf(
             xspf, playlist_id, xspf_url=xspf_url,
             xspf_base_url=base_url(xspf_url))
 
     def _parse_xspf(self, xspf_doc, playlist_id, xspf_url=None, xspf_base_url=None):
         NS_MAP = {
             'xspf': 'http://xspf.org/ns/0/',
             's1': 'http://static.streamone.nl/player/ns/0',
         }
 
         entries = []
         for track in xspf_doc.findall(xpath_with_ns('./xspf:trackList/xspf:track', NS_MAP)):
             title = xpath_text(
                 track, xpath_with_ns('./xspf:title', NS_MAP), 'title', default=playlist_id)
             description = xpath_text(
                 track, xpath_with_ns('./xspf:annotation', NS_MAP), 'description')
             thumbnail = xpath_text(
                 track, xpath_with_ns('./xspf:image', NS_MAP), 'thumbnail')
             duration = float_or_none(
                 xpath_text(track, xpath_with_ns('./xspf:duration', NS_MAP), 'duration'), 1000)
 
             formats = []
             for location in track.findall(xpath_with_ns('./xspf:location', NS_MAP)):
                 format_url = urljoin(xspf_base_url, location.text)
                 if not format_url:
                     continue
                 formats.append({
                     'url': format_url,
                     'manifest_url': xspf_url,
                     'format_id': location.get(xpath_with_ns('s1:label', NS_MAP)),
                     'width': int_or_none(location.get(xpath_with_ns('s1:width', NS_MAP))),
                     'height': int_or_none(location.get(xpath_with_ns('s1:height', NS_MAP))),
                 })
             self._sort_formats(formats)
 
             entries.append({
                 'id': playlist_id,
                 'title': title,
                 'description': description,
                 'thumbnail': thumbnail,
                 'duration': duration,
                 'formats': formats,
             })
         return entries
 
     def _extract_mpd_formats(self, mpd_url, video_id, mpd_id=None, note=None, errnote=None, fatal=True, data=None, headers={}, query={}):
         res = self._download_xml_handle(
             mpd_url, video_id,
             note=note or 'Downloading MPD manifest',
             errnote=errnote or 'Failed to download MPD manifest',
             fatal=fatal, data=data, headers=headers, query=query)
         if res is False:
             return []
         mpd_doc, urlh = res
         if mpd_doc is None:
             return []
         mpd_base_url = base_url(urlh.geturl())
 
         return self._parse_mpd_formats(
             mpd_doc, mpd_id, mpd_base_url, mpd_url)
 
     def _parse_mpd_formats(self, mpd_doc, mpd_id=None, mpd_base_url='', mpd_url=None):
         """
         Parse formats from MPD manifest.
         References:
          1. MPEG-DASH Standard, ISO/IEC 23009-1:2014(E),
             http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip
          2. https://en.wikipedia.org/wiki/Dynamic_Adaptive_Streaming_over_HTTP
         """
         if mpd_doc.get('type') == 'dynamic':
             return []
 
         namespace = self._search_regex(r'(?i)^{([^}]+)?}MPD$', mpd_doc.tag, 'namespace', default=None)
 
         def _add_ns(path):
             return self._xpath_ns(path, namespace)
 
         def is_drm_protected(element):
             return element.find(_add_ns('ContentProtection')) is not None
 
         def extract_multisegment_info(element, ms_parent_info):
             ms_info = ms_parent_info.copy()
 
             # As per [1, 5.3.9.2.2] SegmentList and SegmentTemplate share some
             # common attributes and elements.  We will only extract relevant
             # for us.
             def extract_common(source):
                 segment_timeline = source.find(_add_ns('SegmentTimeline'))
                 if segment_timeline is not None:
                     s_e = segment_timeline.findall(_add_ns('S'))
                     if s_e:
                         ms_info['total_number'] = 0
                         ms_info['s'] = []
                         for s in s_e:
                             r = int(s.get('r', 0))
                             ms_info['total_number'] += 1 + r
                             ms_info['s'].append({
                                 't': int(s.get('t', 0)),
                                 # @d is mandatory (see [1, 5.3.9.6.2, Table 17, page 60])
                                 'd': int(s.attrib['d']),
                                 'r': r,
                             })
                 start_number = source.get('startNumber')
                 if start_number:
                     ms_info['start_number'] = int(start_number)
                 timescale = source.get('timescale')
                 if timescale:
                     ms_info['timescale'] = int(timescale)
                 segment_duration = source.get('duration')
                 if segment_duration:
                     ms_info['segment_duration'] = float(segment_duration)
 
             def extract_Initialization(source):
                 initialization = source.find(_add_ns('Initialization'))
                 if initialization is not None:
                     ms_info['initialization_url'] = initialization.attrib['sourceURL']
 
             segment_list = element.find(_add_ns('SegmentList'))
             if segment_list is not None:
                 extract_common(segment_list)
                 extract_Initialization(segment_list)
                 segment_urls_e = segment_list.findall(_add_ns('SegmentURL'))
                 if segment_urls_e:
                     ms_info['segment_urls'] = [segment.attrib['media'] for segment in segment_urls_e]
             else:
                 segment_template = element.find(_add_ns('SegmentTemplate'))
                 if segment_template is not None:
                     extract_common(segment_template)
                     media = segment_template.get('media')
                     if media:
                         ms_info['media'] = media
                     initialization = segment_template.get('initialization')
                     if initialization:
                         ms_info['initialization'] = initialization
                     else:
                         extract_Initialization(segment_template)
             return ms_info
 
         mpd_duration = parse_duration(mpd_doc.get('mediaPresentationDuration'))
         formats = []
         for period in mpd_doc.findall(_add_ns('Period')):
             period_duration = parse_duration(period.get('duration')) or mpd_duration
             period_ms_info = extract_multisegment_info(period, {
                 'start_number': 1,
                 'timescale': 1,
             })
             for adaptation_set in period.findall(_add_ns('AdaptationSet')):
                 if is_drm_protected(adaptation_set):
                     continue
                 adaption_set_ms_info = extract_multisegment_info(adaptation_set, period_ms_info)
                 for representation in adaptation_set.findall(_add_ns('Representation')):
                     if is_drm_protected(representation):
                         continue
                     representation_attrib = adaptation_set.attrib.copy()
                     representation_attrib.update(representation.attrib)
                     # According to [1, 5.3.7.2, Table 9, page 41], @mimeType is mandatory
                     mime_type = representation_attrib['mimeType']
                     content_type = mime_type.split('/')[0]
                     if content_type == 'text':
                         # TODO implement WebVTT downloading
                         pass
                     elif content_type in ('video', 'audio'):
                         base_url = ''
                         for element in (representation, adaptation_set, period, mpd_doc):
                             base_url_e = element.find(_add_ns('BaseURL'))
                             if base_url_e is not None:
                                 base_url = base_url_e.text + base_url
                                 if re.match(r'^https?://', base_url):
                                     break
                         if mpd_base_url and not re.match(r'^https?://', base_url):
                             if not mpd_base_url.endswith('/') and not base_url.startswith('/'):
                                 mpd_base_url += '/'
                             base_url = mpd_base_url + base_url
                         representation_id = representation_attrib.get('id')
                         lang = representation_attrib.get('lang')
                         url_el = representation.find(_add_ns('BaseURL'))
                         filesize = int_or_none(url_el.attrib.get('{http://youtube.com/yt/2012/10/10}contentLength') if url_el is not None else None)
                         bandwidth = int_or_none(representation_attrib.get('bandwidth'))
                         f = {
                             'format_id': '%s-%s' % (mpd_id, representation_id) if mpd_id else representation_id,
                             'manifest_url': mpd_url,
                             'ext': mimetype2ext(mime_type),
                             'width': int_or_none(representation_attrib.get('width')),
                             'height': int_or_none(representation_attrib.get('height')),
                             'tbr': float_or_none(bandwidth, 1000),
                             'asr': int_or_none(representation_attrib.get('audioSamplingRate')),
                             'fps': int_or_none(representation_attrib.get('frameRate')),
                             'language': lang if lang not in ('mul', 'und', 'zxx', 'mis') else None,
                             'format_note': 'DASH %s' % content_type,
                             'filesize': filesize,
                             'container': mimetype2ext(mime_type) + '_dash',
                         }
                         f.update(parse_codecs(representation_attrib.get('codecs')))
                         representation_ms_info = extract_multisegment_info(representation, adaption_set_ms_info)
 
                         def prepare_template(template_name, identifiers):
                             tmpl = representation_ms_info[template_name]
                             # First of, % characters outside $...$ templates
                             # must be escaped by doubling for proper processing
                             # by % operator string formatting used further (see
                             # https://github.com/ytdl-org/youtube-dl/issues/16867).
                             t = ''
                             in_template = False
                             for c in tmpl:
                                 t += c
                                 if c == '$':
                                     in_template = not in_template
                                 elif c == '%' and not in_template:
                                     t += c
                             # Next, $...$ templates are translated to their
                             # %(...) counterparts to be used with % operator
                             t = t.replace('$RepresentationID$', representation_id)
                             t = re.sub(r'\$(%s)\$' % '|'.join(identifiers), r'%(\1)d', t)
                             t = re.sub(r'\$(%s)%%([^$]+)\$' % '|'.join(identifiers), r'%(\1)\2', t)
                             t.replace('$$', '$')
                             return t
 
                         # @initialization is a regular template like @media one
                         # so it should be handled just the same way (see
                         # https://github.com/ytdl-org/youtube-dl/issues/11605)
                         if 'initialization' in representation_ms_info:
                             initialization_template = prepare_template(
                                 'initialization',
                                 # As per [1, 5.3.9.4.2, Table 15, page 54] $Number$ and
                                 # $Time$ shall not be included for @initialization thus
                                 # only $Bandwidth$ remains
                                 ('Bandwidth', ))
                             representation_ms_info['initialization_url'] = initialization_template % {
                                 'Bandwidth': bandwidth,
                             }
 
                         def location_key(location):
                             return 'url' if re.match(r'^https?://', location) else 'path'
 
                         if 'segment_urls' not in representation_ms_info and 'media' in representation_ms_info:
 
                             media_template = prepare_template('media', ('Number', 'Bandwidth', 'Time'))
                             media_location_key = location_key(media_template)
 
                             # As per [1, 5.3.9.4.4, Table 16, page 55] $Number$ and $Time$
                             # can't be used at the same time
                             if '%(Number' in media_template and 's' not in representation_ms_info:
                                 segment_duration = None
                                 if 'total_number' not in representation_ms_info and 'segment_duration' in representation_ms_info:
                                     segment_duration = float_or_none(representation_ms_info['segment_duration'], representation_ms_info['timescale'])
                                     representation_ms_info['total_number'] = int(math.ceil(float(period_duration) / segment_duration))
                                 representation_ms_info['fragments'] = [{
                                     media_location_key: media_template % {
                                         'Number': segment_number,
                                         'Bandwidth': bandwidth,
                                     },
                                     'duration': segment_duration,
                                 } for segment_number in range(
                                     representation_ms_info['start_number'],
                                     representation_ms_info['total_number'] + representation_ms_info['start_number'])]
                             else:
                                 # $Number*$ or $Time$ in media template with S list available
                                 # Example $Number*$: http://www.svtplay.se/klipp/9023742/stopptid-om-bjorn-borg
                                 # Example $Time$: https://play.arkena.com/embed/avp/v2/player/media/b41dda37-d8e7-4d3f-b1b5-9a9db578bdfe/1/129411
                                 representation_ms_info['fragments'] = []
                                 segment_time = 0
                                 segment_d = None
                                 segment_number = representation_ms_info['start_number']
 
                                 def add_segment_url():
                                     segment_url = media_template % {
                                         'Time': segment_time,
                                         'Bandwidth': bandwidth,
                                         'Number': segment_number,
                                     }
                                     representation_ms_info['fragments'].append({
                                         media_location_key: segment_url,
                                         'duration': float_or_none(segment_d, representation_ms_info['timescale']),
                                     })
 
                                 for num, s in enumerate(representation_ms_info['s']):
                                     segment_time = s.get('t') or segment_time
                                     segment_d = s['d']
                                     add_segment_url()
                                     segment_number += 1
                                     for r in range(s.get('r', 0)):
                                         segment_time += segment_d
                                         add_segment_url()
                                         segment_number += 1
                                     segment_time += segment_d
                         elif 'segment_urls' in representation_ms_info and 's' in representation_ms_info:
                             # No media template
                             # Example: https://www.youtube.com/watch?v=iXZV5uAYMJI
                             # or any YouTube dashsegments video
                             fragments = []
                             segment_index = 0
                             timescale = representation_ms_info['timescale']
                             for s in representation_ms_info['s']:
                                 duration = float_or_none(s['d'], timescale)
                                 for r in range(s.get('r', 0) + 1):
                                     segment_uri = representation_ms_info['segment_urls'][segment_index]
                                     fragments.append({
                                         location_key(segment_uri): segment_uri,
                                         'duration': duration,
                                     })
                                     segment_index += 1
                             representation_ms_info['fragments'] = fragments
                         elif 'segment_urls' in representation_ms_info:
                             # Segment URLs with no SegmentTimeline
                             # Example: https://www.seznam.cz/zpravy/clanek/cesko-zasahne-vitr-o-sile-vichrice-muze-byt-i-zivotu-nebezpecny-39091
                             # https://github.com/ytdl-org/youtube-dl/pull/14844
                             fragments = []
                             segment_duration = float_or_none(
                                 representation_ms_info['segment_duration'],
                                 representation_ms_info['timescale']) if 'segment_duration' in representation_ms_info else None
                             for segment_url in representation_ms_info['segment_urls']:
                                 fragment = {
                                     location_key(segment_url): segment_url,
                                 }
                                 if segment_duration:
                                     fragment['duration'] = segment_duration
                                 fragments.append(fragment)
                             representation_ms_info['fragments'] = fragments
                         # If there is a fragments key available then we correctly recognized fragmented media.
                         # Otherwise we will assume unfragmented media with direct access. Technically, such
                         # assumption is not necessarily correct since we may simply have no support for
                         # some forms of fragmented media renditions yet, but for now we'll use this fallback.
                         if 'fragments' in representation_ms_info:
                             f.update({
                                 # NB: mpd_url may be empty when MPD manifest is parsed from a string
                                 'url': mpd_url or base_url,
                                 'fragment_base_url': base_url,
                                 'fragments': [],
                                 'protocol': 'http_dash_segments',
                             })
                             if 'initialization_url' in representation_ms_info:
                                 initialization_url = representation_ms_info['initialization_url']
                                 if not f.get('url'):
                                     f['url'] = initialization_url
                                 f['fragments'].append({location_key(initialization_url): initialization_url})
                             f['fragments'].extend(representation_ms_info['fragments'])
                         else:
                             # Assuming direct URL to unfragmented media.
                             f['url'] = base_url
                         formats.append(f)
                     else:
                         self.report_warning('Unknown MIME type %s in DASH manifest' % mime_type)
         return formats
 
     def _extract_ism_formats(self, ism_url, video_id, ism_id=None, note=None, errnote=None, fatal=True, data=None, headers={}, query={}):
         res = self._download_xml_handle(
             ism_url, video_id,
             note=note or 'Downloading ISM manifest',
             errnote=errnote or 'Failed to download ISM manifest',
             fatal=fatal, data=data, headers=headers, query=query)
         if res is False:
             return []
         ism_doc, urlh = res
         if ism_doc is None:
             return []
 
         return self._parse_ism_formats(ism_doc, 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 []
 
         duration = int(ism_doc.attrib['Duration'])
         timescale = int_or_none(ism_doc.get('TimeScale')) or 10000000
 
         formats = []
         for stream in ism_doc.findall('StreamIndex'):
             stream_type = stream.get('Type')
             if stream_type not in ('video', 'audio'):
                 continue
             url_pattern = stream.attrib['Url']
             stream_timescale = int_or_none(stream.get('TimeScale')) or timescale
             stream_name = stream.get('Name')
             for track in stream.findall('QualityLevel'):
                 fourcc = track.get('FourCC', 'AACL' if track.get('AudioTag') == '255' else None)
                 # TODO: add support for WVC1 and WMAP
                 if fourcc not in ('H264', 'AVC1', 'AACL'):
                     self.report_warning('%s is not a supported codec' % fourcc)
                     continue
                 tbr = int(track.attrib['Bitrate']) // 1000
                 # [1] does not mention Width and Height attributes. However,
                 # 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)
                 track_url_pattern = compat_urlparse.urljoin(ism_url, track_url_pattern)
 
                 fragments = []
                 fragment_ctx = {
                     'time': 0,
                 }
                 stream_fragments = stream.findall('c')
                 for stream_fragment_index, stream_fragment in enumerate(stream_fragments):
                     fragment_ctx['time'] = int_or_none(stream_fragment.get('t')) or fragment_ctx['time']
                     fragment_repeat = int_or_none(stream_fragment.get('r')) or 1
                     fragment_ctx['duration'] = int_or_none(stream_fragment.get('d'))
                     if not fragment_ctx['duration']:
                         try:
                             next_fragment_time = int(stream_fragment[stream_fragment_index + 1].attrib['t'])
                         except IndexError:
                             next_fragment_time = duration
                         fragment_ctx['duration'] = (next_fragment_time - fragment_ctx['time']) / fragment_repeat
                     for _ in range(fragment_repeat):
                         fragments.append({
                             'url': re.sub(r'{start[ _]time}', compat_str(fragment_ctx['time']), track_url_pattern),
                             'duration': fragment_ctx['duration'] / stream_timescale,
                         })
                         fragment_ctx['time'] += fragment_ctx['duration']
 
                 format_id = []
                 if ism_id:
                     format_id.append(ism_id)
                 if stream_name:
                     format_id.append(stream_name)
                 format_id.append(compat_str(tbr))
 
                 formats.append({
                     'format_id': '-'.join(format_id),
                     'url': ism_url,
                     'manifest_url': ism_url,
                     'ext': 'ismv' if stream_type == 'video' else 'isma',
                     'width': width,
                     'height': height,
                     'tbr': tbr,
                     'asr': sampling_rate,
                     'vcodec': 'none' if stream_type == 'audio' else fourcc,
                     'acodec': 'none' if stream_type == 'video' else fourcc,
                     'protocol': 'ism',
                     'fragments': fragments,
                     '_download_params': {
                         'duration': duration,
                         'timescale': stream_timescale,
                         'width': width or 0,
                         'height': height or 0,
                         'fourcc': fourcc,
                         'codec_private_data': track.get('CodecPrivateData'),
                         'sampling_rate': sampling_rate,
                         'channels': int_or_none(track.get('Channels', 2)),
                         'bits_per_sample': int_or_none(track.get('BitsPerSample', 16)),
                         'nal_unit_length_field': int_or_none(track.get('NALUnitLengthField', 4)),
                     },
                 })
         return formats
 
     def _parse_html5_media_entries(self, base_url, webpage, video_id, m3u8_id=None, m3u8_entry_protocol='m3u8', mpd_id=None, preference=None):
         def absolute_url(item_url):
             return urljoin(base_url, item_url)
 
         def parse_content_type(content_type):
             if not content_type:
                 return {}
             ctr = re.search(r'(?P<mimetype>[^/]+/[^;]+)(?:;\s*codecs="?(?P<codecs>[^"]+))?', content_type)
             if ctr:
                 mimetype, codecs = ctr.groups()
                 f = parse_codecs(codecs)
                 f['ext'] = mimetype2ext(mimetype)
                 return f
             return {}
 
         def _media_formats(src, cur_media_type, type_info={}):
             full_url = absolute_url(src)
             ext = type_info.get('ext') or determine_ext(full_url)
             if ext == 'm3u8':
                 is_plain_url = False
                 formats = self._extract_m3u8_formats(
                     full_url, video_id, ext='mp4',
                     entry_protocol=m3u8_entry_protocol, m3u8_id=m3u8_id,
                     preference=preference, fatal=False)
             elif ext == 'mpd':
                 is_plain_url = False
                 formats = self._extract_mpd_formats(
                     full_url, video_id, mpd_id=mpd_id, fatal=False)
             else:
                 is_plain_url = True
                 formats = [{
                     'url': full_url,
                     'vcodec': 'none' if cur_media_type == 'audio' else None,
                 }]
             return is_plain_url, formats
 
         entries = []
         # amp-video and amp-audio are very similar to their HTML5 counterparts
         # so we wll include them right here (see
         # https://www.ampproject.org/docs/reference/components/amp-video)
         # For dl8-* tags see https://delight-vr.com/documentation/dl8-video/
         _MEDIA_TAG_NAME_RE = r'(?:(?:amp|dl8(?:-live)?)-)?(video|audio)'
         media_tags = [(media_tag, media_tag_name, media_type, '')
                       for media_tag, media_tag_name, media_type
                       in re.findall(r'(?s)(<(%s)[^>]*/>)' % _MEDIA_TAG_NAME_RE, webpage)]
         media_tags.extend(re.findall(
             # We only allow video|audio followed by a whitespace or '>'.
             # Allowing more characters may end up in significant slow down (see
             # https://github.com/ytdl-org/youtube-dl/issues/11979, example URL:
             # http://www.porntrex.com/maps/videositemap.xml).
             r'(?s)(<(?P<tag>%s)(?:\s+[^>]*)?>)(.*?)</(?P=tag)>' % _MEDIA_TAG_NAME_RE, webpage))
         for media_tag, _, media_type, media_content in media_tags:
             media_info = {
                 'formats': [],
                 'subtitles': {},
             }
             media_attributes = extract_attributes(media_tag)
             src = strip_or_none(media_attributes.get('src'))
             if src:
                 _, formats = _media_formats(src, media_type)
                 media_info['formats'].extend(formats)
             media_info['thumbnail'] = absolute_url(media_attributes.get('poster'))
             if media_content:
                 for source_tag in re.findall(r'<source[^>]+>', media_content):
                     s_attr = extract_attributes(source_tag)
                     # data-video-src and data-src are non standard but seen
                     # several times in the wild
                     src = strip_or_none(dict_get(s_attr, ('src', 'data-video-src', 'data-src')))
                     if not src:
                         continue
                     f = parse_content_type(s_attr.get('type'))
                     is_plain_url, formats = _media_formats(src, media_type, f)
                     if is_plain_url:
                         # width, height, res, label and title attributes are
                         # all not standard but seen several times in the wild
                         labels = [
                             s_attr.get(lbl)
                             for lbl in ('label', 'title')
                             if str_or_none(s_attr.get(lbl))
                         ]
                         width = int_or_none(s_attr.get('width'))
                         height = (int_or_none(s_attr.get('height'))
                                   or int_or_none(s_attr.get('res')))
                         if not width or not height:
                             for lbl in labels:
                                 resolution = parse_resolution(lbl)
                                 if not resolution:
                                     continue
                                 width = width or resolution.get('width')
                                 height = height or resolution.get('height')
                         for lbl in labels:
                             tbr = parse_bitrate(lbl)
                             if tbr:
                                 break
                         else:
                             tbr = None
                         f.update({
                             'width': width,
                             'height': height,
                             'tbr': tbr,
                             'format_id': s_attr.get('label') or s_attr.get('title'),
                         })
                         f.update(formats[0])
                         media_info['formats'].append(f)
                     else:
                         media_info['formats'].extend(formats)
                 for track_tag in re.findall(r'<track[^>]+>', media_content):
                     track_attributes = extract_attributes(track_tag)
                     kind = track_attributes.get('kind')
                     if not kind or kind in ('subtitles', 'captions'):
                         src = strip_or_none(track_attributes.get('src'))
                         if not src:
                             continue
                         lang = track_attributes.get('srclang') or track_attributes.get('lang') or track_attributes.get('label')
                         media_info['subtitles'].setdefault(lang, []).append({
                             'url': absolute_url(src),
                         })
             for f in media_info['formats']:
                 f.setdefault('http_headers', {})['Referer'] = base_url
             if media_info['formats'] or media_info['subtitles']:
                 entries.append(media_info)
         return entries
 
     def _extract_akamai_formats(self, manifest_url, video_id, hosts={}):
         signed = 'hdnea=' in manifest_url
         if not signed:
             # https://learn.akamai.com/en-us/webhelp/media-services-on-demand/stream-packaging-user-guide/GUID-BE6C0F73-1E06-483B-B0EA-57984B91B7F9.html
             manifest_url = re.sub(
                 r'(?:b=[\d,-]+|(?:__a__|attributes)=off|__b__=\d+)&?',
                 '', manifest_url).strip('?')
 
         formats = []
 
         hdcore_sign = 'hdcore=3.7.0'
         f4m_url = re.sub(r'(https?://[^/]+)/i/', r'\1/z/', manifest_url).replace('/master.m3u8', '/manifest.f4m')
         hds_host = hosts.get('hds')
         if hds_host:
             f4m_url = re.sub(r'(https?://)[^/]+', r'\1' + hds_host, f4m_url)
         if 'hdcore=' not in f4m_url:
             f4m_url += ('&' if '?' in f4m_url else '?') + hdcore_sign
         f4m_formats = self._extract_f4m_formats(
             f4m_url, video_id, f4m_id='hds', fatal=False)
         for entry in f4m_formats:
             entry.update({'extra_param_to_segment_url': hdcore_sign})
         formats.extend(f4m_formats)
 
         m3u8_url = re.sub(r'(https?://[^/]+)/z/', r'\1/i/', manifest_url).replace('/manifest.f4m', '/master.m3u8')
         hls_host = hosts.get('hls')
         if hls_host:
             m3u8_url = re.sub(r'(https?://)[^/]+', r'\1' + hls_host, m3u8_url)
         m3u8_formats = self._extract_m3u8_formats(
             m3u8_url, video_id, 'mp4', 'm3u8_native',
             m3u8_id='hls', fatal=False)
         formats.extend(m3u8_formats)
 
         http_host = hosts.get('http')
         if http_host and m3u8_formats and not signed:
             REPL_REGEX = r'https?://[^/]+/i/([^,]+),([^/]+),([^/]+)\.csmil/.+'
             qualities = re.match(REPL_REGEX, m3u8_url).group(2).split(',')
             qualities_length = len(qualities)
             if len(m3u8_formats) in (qualities_length, qualities_length + 1):
                 i = 0
                 for f in m3u8_formats:
                     if f['vcodec'] != 'none':
                         for protocol in ('http', 'https'):
                             http_f = f.copy()
                             del http_f['manifest_url']
                             http_url = re.sub(
                                 REPL_REGEX, protocol + r'://%s/\g<1>%s\3' % (http_host, qualities[i]), f['url'])
                             http_f.update({
                                 'format_id': http_f['format_id'].replace('hls-', protocol + '-'),
                                 'url': http_url,
                                 'protocol': protocol,
                             })
                             formats.append(http_f)
                         i += 1
 
         return formats
 
     def _extract_wowza_formats(self, url, video_id, m3u8_entry_protocol='m3u8_native', skip_protocols=[]):
         query = compat_urlparse.urlparse(url).query
         url = re.sub(r'/(?:manifest|playlist|jwplayer)\.(?:m3u8|f4m|mpd|smil)', '', url)
         mobj = re.search(
             r'(?:(?:http|rtmp|rtsp)(?P<s>s)?:)?(?P<url>//[^?]+)', url)
         url_base = mobj.group('url')
         http_base_url = '%s%s:%s' % ('http', mobj.group('s') or '', url_base)
         formats = []
 
         def manifest_url(manifest):
             m_url = '%s/%s' % (http_base_url, manifest)
             if query:
                 m_url += '?%s' % query
             return m_url
 
         if 'm3u8' not in skip_protocols:
             formats.extend(self._extract_m3u8_formats(
                 manifest_url('playlist.m3u8'), video_id, 'mp4',
                 m3u8_entry_protocol, m3u8_id='hls', fatal=False))
         if 'f4m' not in skip_protocols:
             formats.extend(self._extract_f4m_formats(
                 manifest_url('manifest.f4m'),
                 video_id, f4m_id='hds', fatal=False))
         if 'dash' not in skip_protocols:
             formats.extend(self._extract_mpd_formats(
                 manifest_url('manifest.mpd'),
                 video_id, mpd_id='dash', fatal=False))
         if re.search(r'(?:/smil:|\.smil)', url_base):
             if 'smil' not in skip_protocols:
                 rtmp_formats = self._extract_smil_formats(
                     manifest_url('jwplayer.smil'),
                     video_id, fatal=False)
                 for rtmp_format in rtmp_formats:
                     rtsp_format = rtmp_format.copy()
                     rtsp_format['url'] = '%s/%s' % (rtmp_format['url'], rtmp_format['play_path'])
                     del rtsp_format['play_path']
                     del rtsp_format['ext']
                     rtsp_format.update({
                         'url': rtsp_format['url'].replace('rtmp://', 'rtsp://'),
                         'format_id': rtmp_format['format_id'].replace('rtmp', 'rtsp'),
                         'protocol': 'rtsp',
                     })
                     formats.extend([rtmp_format, rtsp_format])
         else:
             for protocol in ('rtmp', 'rtsp'):
                 if protocol not in skip_protocols:
                     formats.append({
                         'url': '%s:%s' % (protocol, url_base),
                         'format_id': protocol,
                         'protocol': protocol,
                     })
         return formats
 
     def _find_jwplayer_data(self, webpage, video_id=None, transform_source=js_to_json):
         mobj = re.search(
             r'(?s)jwplayer\((?P<quote>[\'"])[^\'" ]+(?P=quote)\)(?!</script>).*?\.setup\s*\((?P<options>[^)]+)\)',
             webpage)
         if mobj:
             try:
                 jwplayer_data = self._parse_json(mobj.group('options'),
                                                  video_id=video_id,
                                                  transform_source=transform_source)
             except ExtractorError:
                 pass
             else:
                 if isinstance(jwplayer_data, dict):
                     return jwplayer_data
 
     def _extract_jwplayer_data(self, webpage, video_id, *args, **kwargs):
         jwplayer_data = self._find_jwplayer_data(
             webpage, video_id, transform_source=js_to_json)
         return self._parse_jwplayer_data(
             jwplayer_data, video_id, *args, **kwargs)
 
     def _parse_jwplayer_data(self, jwplayer_data, video_id=None, require_title=True,
                              m3u8_id=None, mpd_id=None, rtmp_params=None, base_url=None):
         # JWPlayer backward compatibility: flattened playlists
         # https://github.com/jwplayer/jwplayer/blob/v7.4.3/src/js/api/config.js#L81-L96
         if 'playlist' not in jwplayer_data:
             jwplayer_data = {'playlist': [jwplayer_data]}
 
         entries = []
 
         # JWPlayer backward compatibility: single playlist item
         # https://github.com/jwplayer/jwplayer/blob/v7.7.0/src/js/playlist/playlist.js#L10
         if not isinstance(jwplayer_data['playlist'], list):
             jwplayer_data['playlist'] = [jwplayer_data['playlist']]
 
         for video_data in jwplayer_data['playlist']:
             # JWPlayer backward compatibility: flattened sources
             # https://github.com/jwplayer/jwplayer/blob/v7.4.3/src/js/playlist/item.js#L29-L35
             if 'sources' not in video_data:
                 video_data['sources'] = [video_data]
 
             this_video_id = video_id or video_data['mediaid']
 
             formats = self._parse_jwplayer_formats(
                 video_data['sources'], video_id=this_video_id, m3u8_id=m3u8_id,
                 mpd_id=mpd_id, rtmp_params=rtmp_params, base_url=base_url)
 
             subtitles = {}
             tracks = video_data.get('tracks')
             if tracks and isinstance(tracks, list):
                 for track in tracks:
                     if not isinstance(track, dict):
                         continue
                     track_kind = track.get('kind')
                     if not track_kind or not isinstance(track_kind, compat_str):
                         continue
                     if track_kind.lower() not in ('captions', 'subtitles'):
                         continue
                     track_url = urljoin(base_url, track.get('file'))
                     if not track_url:
                         continue
                     subtitles.setdefault(track.get('label') or 'en', []).append({
                         'url': self._proto_relative_url(track_url)
                     })
 
             entry = {
                 'id': this_video_id,
                 'title': unescapeHTML(video_data['title'] if require_title else video_data.get('title')),
                 'description': clean_html(video_data.get('description')),
                 'thumbnail': urljoin(base_url, self._proto_relative_url(video_data.get('image'))),
                 'timestamp': int_or_none(video_data.get('pubdate')),
                 'duration': float_or_none(jwplayer_data.get('duration') or video_data.get('duration')),
                 'subtitles': subtitles,
             }
             # https://github.com/jwplayer/jwplayer/blob/master/src/js/utils/validator.js#L32
             if len(formats) == 1 and re.search(r'^(?:http|//).*(?:youtube\.com|youtu\.be)/.+', formats[0]['url']):
                 entry.update({
                     '_type': 'url_transparent',
                     'url': formats[0]['url'],
                 })
             else:
                 self._sort_formats(formats)
                 entry['formats'] = formats
             entries.append(entry)
         if len(entries) == 1:
             return entries[0]
         else:
             return self.playlist_result(entries)
 
     def _parse_jwplayer_formats(self, jwplayer_sources_data, video_id=None,
                                 m3u8_id=None, mpd_id=None, rtmp_params=None, base_url=None):
         urls = []
         formats = []
         for source in jwplayer_sources_data:
             if not isinstance(source, dict):
                 continue
             source_url = urljoin(
                 base_url, self._proto_relative_url(source.get('file')))
             if not source_url or source_url in urls:
                 continue
             urls.append(source_url)
             source_type = source.get('type') or ''
             ext = mimetype2ext(source_type) or determine_ext(source_url)
             if source_type == 'hls' or ext == 'm3u8':
                 formats.extend(self._extract_m3u8_formats(
                     source_url, video_id, 'mp4', entry_protocol='m3u8_native',
                     m3u8_id=m3u8_id, fatal=False))
             elif source_type == 'dash' or ext == 'mpd':
                 formats.extend(self._extract_mpd_formats(
                     source_url, video_id, mpd_id=mpd_id, fatal=False))
             elif ext == 'smil':
                 formats.extend(self._extract_smil_formats(
                     source_url, video_id, fatal=False))
             # https://github.com/jwplayer/jwplayer/blob/master/src/js/providers/default.js#L67
             elif source_type.startswith('audio') or ext in (
                     'oga', 'aac', 'mp3', 'mpeg', 'vorbis'):
                 formats.append({
                     'url': source_url,
                     'vcodec': 'none',
                     'ext': ext,
                 })
             else:
                 height = int_or_none(source.get('height'))
                 if height is None:
                     # Often no height is provided but there is a label in
                     # format like "1080p", "720p SD", or 1080.
                     height = int_or_none(self._search_regex(
                         r'^(\d{3,4})[pP]?(?:\b|$)', compat_str(source.get('label') or ''),
                         'height', default=None))
                 a_format = {
                     'url': source_url,
                     'width': int_or_none(source.get('width')),
                     'height': height,
                     'tbr': int_or_none(source.get('bitrate')),
                     'ext': ext,
                 }
                 if source_url.startswith('rtmp'):
                     a_format['ext'] = 'flv'
                     # See com/longtailvideo/jwplayer/media/RTMPMediaProvider.as
                     # of jwplayer.flash.swf
                     rtmp_url_parts = re.split(
                         r'((?:mp4|mp3|flv):)', source_url, 1)
                     if len(rtmp_url_parts) == 3:
                         rtmp_url, prefix, play_path = rtmp_url_parts
                         a_format.update({
                             'url': rtmp_url,
                             'play_path': prefix + play_path,
                         })
                     if rtmp_params:
                         a_format.update(rtmp_params)
                 formats.append(a_format)
         return formats
 
     def _live_title(self, name):
         """ Generate the title for a live video """
         now = datetime.datetime.now()
         now_str = now.strftime('%Y-%m-%d %H:%M')
         return name + ' ' + now_str
 
     def _int(self, v, name, fatal=False, **kwargs):
         res = int_or_none(v, **kwargs)
         if 'get_attr' in kwargs:
             print(getattr(v, kwargs['get_attr']))
         if res is None:
             msg = 'Failed to extract %s: Could not parse value %r' % (name, v)
             if fatal:
                 raise ExtractorError(msg)
             else:
                 self._downloader.report_warning(msg)
         return res
 
     def _float(self, v, name, fatal=False, **kwargs):
         res = float_or_none(v, **kwargs)
         if res is None:
             msg = 'Failed to extract %s: Could not parse value %r' % (name, v)
             if fatal:
                 raise ExtractorError(msg)
             else:
                 self._downloader.report_warning(msg)
         return res
 
     def _set_cookie(self, domain, name, value, expire_time=None, port=None,
                     path='/', secure=False, discard=False, rest={}, **kwargs):
         cookie = compat_cookiejar_Cookie(
             0, name, value, port, port is not None, domain, True,
             domain.startswith('.'), path, True, secure, expire_time,
             discard, None, None, rest)
         self._downloader.cookiejar.set_cookie(cookie)
 
     def _get_cookies(self, url):
         """ Return a compat_cookies_SimpleCookie with the cookies for the url """
         req = sanitized_Request(url)
         self._downloader.cookiejar.add_cookie_header(req)
         return compat_cookies_SimpleCookie(req.get_header('Cookie'))
 
     def _apply_first_set_cookie_header(self, url_handle, cookie):
         """
         Apply first Set-Cookie header instead of the last. Experimental.
 
         Some sites (e.g. [1-3]) may serve two cookies under the same name
         in Set-Cookie header and expect the first (old) one to be set rather
         than second (new). However, as of RFC6265 the newer one cookie
         should be set into cookie store what actually happens.
         We will workaround this issue by resetting the cookie to
         the first one manually.
         1. https://new.vk.com/
         2. https://github.com/ytdl-org/youtube-dl/issues/9841#issuecomment-227871201
         3. https://learning.oreilly.com/
         """
         for header, cookies in url_handle.headers.items():
             if header.lower() != 'set-cookie':
                 continue
             if sys.version_info[0] >= 3:
                 cookies = cookies.encode('iso-8859-1')
             cookies = cookies.decode('utf-8')
             cookie_value = re.search(
                 r'%s=(.+?);.*?\b[Dd]omain=(.+?)(?:[,;]|$)' % cookie, cookies)
             if cookie_value:
                 value, domain = cookie_value.groups()
                 self._set_cookie(domain, cookie, value)
                 break
 
     def get_testcases(self, include_onlymatching=False):
         t = getattr(self, '_TEST', None)
         if t:
             assert not hasattr(self, '_TESTS'), \
                 '%s has _TEST and _TESTS' % type(self).__name__
             tests = [t]
         else:
             tests = getattr(self, '_TESTS', [])
         for t in tests:
             if not include_onlymatching and t.get('only_matching', False):
                 continue
             t['name'] = type(self).__name__[:-len('IE')]
             yield t
 
     def is_suitable(self, age_limit):
         """ Test whether the extractor is generally suitable for the given
         age limit (i.e. pornographic sites are not, all others usually are) """
 
         any_restricted = False
         for tc in self.get_testcases(include_onlymatching=False):
             if tc.get('playlist', []):
                 tc = tc['playlist'][0]
             is_restricted = age_restricted(
                 tc.get('info_dict', {}).get('age_limit'), age_limit)
             if not is_restricted:
                 return True
             any_restricted = any_restricted or is_restricted
         return not any_restricted
 
     def extract_subtitles(self, *args, **kwargs):
         if (self._downloader.params.get('writesubtitles', False)
                 or self._downloader.params.get('listsubtitles')):
             return self._get_subtitles(*args, **kwargs)
         return {}
 
     def _get_subtitles(self, *args, **kwargs):
         raise NotImplementedError('This method must be implemented by subclasses')
 
     @staticmethod
     def _merge_subtitle_items(subtitle_list1, subtitle_list2):
         """ Merge subtitle items for one language. Items with duplicated URLs
         will be dropped. """
         list1_urls = set([item['url'] for item in subtitle_list1])
         ret = list(subtitle_list1)
         ret.extend([item for item in subtitle_list2 if item['url'] not in list1_urls])
         return ret
 
     @classmethod
     def _merge_subtitles(cls, subtitle_dict1, subtitle_dict2):
         """ Merge two subtitle dictionaries, language by language. """
         ret = dict(subtitle_dict1)
         for lang in subtitle_dict2:
             ret[lang] = cls._merge_subtitle_items(subtitle_dict1.get(lang, []), subtitle_dict2[lang])
         return ret
 
     def extract_automatic_captions(self, *args, **kwargs):
         if (self._downloader.params.get('writeautomaticsub', False)
                 or self._downloader.params.get('listsubtitles')):
             return self._get_automatic_captions(*args, **kwargs)
         return {}
 
     def _get_automatic_captions(self, *args, **kwargs):
         raise NotImplementedError('This method must be implemented by subclasses')
 
     def mark_watched(self, *args, **kwargs):
         if (self._downloader.params.get('mark_watched', False)
                 and (self._get_login_info()[0] is not None
                      or self._downloader.params.get('cookiefile') is not None)):
             self._mark_watched(*args, **kwargs)
 
     def _mark_watched(self, *args, **kwargs):
         raise NotImplementedError('This method must be implemented by subclasses')
 
     def geo_verification_headers(self):
         headers = {}
         geo_verification_proxy = self._downloader.params.get('geo_verification_proxy')
         if geo_verification_proxy:
             headers['Ytdl-request-proxy'] = geo_verification_proxy
         return headers
 
     def _generic_id(self, url):
         return compat_urllib_parse_unquote(os.path.splitext(url.rstrip('/').split('/')[-1])[0])
 
     def _generic_title(self, url):
         return compat_urllib_parse_unquote(os.path.splitext(url_basename(url))[0])
 
 
 class SearchInfoExtractor(InfoExtractor):
     """
     Base class for paged search queries extractors.
     They accept URLs in the format _SEARCH_KEY(|all|[0-9]):{query}
     Instances should define _SEARCH_KEY and _MAX_RESULTS.
     """
 
     @classmethod
     def _make_valid_url(cls):
         return r'%s(?P<prefix>|[1-9][0-9]*|all):(?P<query>[\s\S]+)' % cls._SEARCH_KEY
 
     @classmethod
     def suitable(cls, url):
         return re.match(cls._make_valid_url(), url) is not None
 
     def _real_extract(self, query):
         mobj = re.match(self._make_valid_url(), query)
         if mobj is None:
             raise ExtractorError('Invalid search query "%s"' % query)
 
         prefix = mobj.group('prefix')
         query = mobj.group('query')
         if prefix == '':
             return self._get_n_results(query, 1)
         elif prefix == 'all':
             return self._get_n_results(query, self._MAX_RESULTS)
         else:
             n = int(prefix)
             if n <= 0:
                 raise ExtractorError('invalid download number %s for query "%s"' % (n, query))
             elif n > self._MAX_RESULTS:
                 self._downloader.report_warning('%s returns max %i results (you requested %i)' % (self._SEARCH_KEY, self._MAX_RESULTS, n))
                 n = self._MAX_RESULTS
             return self._get_n_results(query, n)
 
     def _get_n_results(self, query, n):
         """Get a specified number of results for a query"""
         raise NotImplementedError('This method must be implemented by subclasses')
 
     @property
     def SEARCH_KEY(self):
         return self._SEARCH_KEY