yt-dlp/yt_dlp/downloader/hls.py
2021-07-22 04:30:11 +05:30

325 lines
14 KiB
Python

from __future__ import unicode_literals
import re
import io
import binascii
from ..downloader import _get_real_downloader
from .fragment import FragmentFD, can_decrypt_frag
from .external import FFmpegFD
from ..compat import (
compat_urlparse,
)
from ..utils import (
parse_m3u8_attributes,
update_url_query,
bug_reports_message,
)
from .. import webvtt
class HlsFD(FragmentFD):
"""
Download segments in a m3u8 manifest. External downloaders can take over
the fragment downloads by supporting the 'm3u8_frag_urls' protocol and
re-defining 'supports_manifest' function
"""
FD_NAME = 'hlsnative'
@staticmethod
def can_download(manifest, info_dict, allow_unplayable_formats=False, with_crypto=can_decrypt_frag):
UNSUPPORTED_FEATURES = [
# r'#EXT-X-BYTERANGE', # playlists composed of byte ranges of media files [2]
# Live streams heuristic does not always work (e.g. geo restricted to Germany
# http://hls-geo.daserste.de/i/videoportal/Film/c_620000/622873/format,716451,716457,716450,716458,716459,.mp4.csmil/index_4_av.m3u8?null=0)
# r'#EXT-X-MEDIA-SEQUENCE:(?!0$)', # live streams [3]
# This heuristic also is not correct since segments may not be appended as well.
# Twitch vods of finished streams have EXT-X-PLAYLIST-TYPE:EVENT despite
# no segments will definitely be appended to the end of the playlist.
# r'#EXT-X-PLAYLIST-TYPE:EVENT', # media segments may be appended to the end of
# # event media playlists [4]
# r'#EXT-X-MAP:', # media initialization [5]
# 1. https://tools.ietf.org/html/draft-pantos-http-live-streaming-17#section-4.3.2.4
# 2. https://tools.ietf.org/html/draft-pantos-http-live-streaming-17#section-4.3.2.2
# 3. https://tools.ietf.org/html/draft-pantos-http-live-streaming-17#section-4.3.3.2
# 4. https://tools.ietf.org/html/draft-pantos-http-live-streaming-17#section-4.3.3.5
# 5. https://tools.ietf.org/html/draft-pantos-http-live-streaming-17#section-4.3.2.5
]
if not allow_unplayable_formats:
UNSUPPORTED_FEATURES += [
r'#EXT-X-KEY:METHOD=(?!NONE|AES-128)', # encrypted streams [1]
]
def check_results():
yield not info_dict.get('is_live')
is_aes128_enc = '#EXT-X-KEY:METHOD=AES-128' in manifest
yield with_crypto or not is_aes128_enc
yield not (is_aes128_enc and r'#EXT-X-BYTERANGE' in manifest)
for feature in UNSUPPORTED_FEATURES:
yield not re.search(feature, manifest)
return all(check_results())
def real_download(self, filename, info_dict):
man_url = info_dict['url']
self.to_screen('[%s] Downloading m3u8 manifest' % self.FD_NAME)
urlh = self.ydl.urlopen(self._prepare_url(info_dict, man_url))
man_url = urlh.geturl()
s = urlh.read().decode('utf-8', 'ignore')
if not self.can_download(s, info_dict, self.params.get('allow_unplayable_formats')):
if info_dict.get('extra_param_to_segment_url') or info_dict.get('_decryption_key_url'):
self.report_error('pycryptodome not found. Please install')
return False
if self.can_download(s, info_dict, with_crypto=True):
self.report_warning('pycryptodome is needed to download this file natively')
fd = FFmpegFD(self.ydl, self.params)
self.report_warning(
'%s detected unsupported features; extraction will be delegated to %s' % (self.FD_NAME, fd.get_basename()))
# TODO: Make progress updates work without hooking twice
# for ph in self._progress_hooks:
# fd.add_progress_hook(ph)
return fd.real_download(filename, info_dict)
is_webvtt = info_dict['ext'] == 'vtt'
if is_webvtt:
real_downloader = None # Packing the fragments is not currently supported for external downloader
else:
real_downloader = _get_real_downloader(info_dict, 'm3u8_frag_urls', self.params, None)
if real_downloader and not real_downloader.supports_manifest(s):
real_downloader = None
if real_downloader:
self.to_screen(
'[%s] Fragment downloads will be delegated to %s' % (self.FD_NAME, real_downloader.get_basename()))
def is_ad_fragment_start(s):
return (s.startswith('#ANVATO-SEGMENT-INFO') and 'type=ad' in s
or s.startswith('#UPLYNK-SEGMENT') and s.endswith(',ad'))
def is_ad_fragment_end(s):
return (s.startswith('#ANVATO-SEGMENT-INFO') and 'type=master' in s
or s.startswith('#UPLYNK-SEGMENT') and s.endswith(',segment'))
fragments = []
media_frags = 0
ad_frags = 0
ad_frag_next = False
for line in s.splitlines():
line = line.strip()
if not line:
continue
if line.startswith('#'):
if is_ad_fragment_start(line):
ad_frag_next = True
elif is_ad_fragment_end(line):
ad_frag_next = False
continue
if ad_frag_next:
ad_frags += 1
continue
media_frags += 1
ctx = {
'filename': filename,
'total_frags': media_frags,
'ad_frags': ad_frags,
}
if real_downloader:
self._prepare_external_frag_download(ctx)
else:
self._prepare_and_start_frag_download(ctx, info_dict)
extra_state = ctx.setdefault('extra_state', {})
format_index = info_dict.get('format_index')
extra_query = None
extra_param_to_segment_url = info_dict.get('extra_param_to_segment_url')
if extra_param_to_segment_url:
extra_query = compat_urlparse.parse_qs(extra_param_to_segment_url)
i = 0
media_sequence = 0
decrypt_info = {'METHOD': 'NONE'}
byte_range = {}
discontinuity_count = 0
frag_index = 0
ad_frag_next = False
for line in s.splitlines():
line = line.strip()
if line:
if not line.startswith('#'):
if format_index and discontinuity_count != format_index:
continue
if ad_frag_next:
continue
frag_index += 1
if frag_index <= ctx['fragment_index']:
continue
frag_url = (
line
if re.match(r'^https?://', line)
else compat_urlparse.urljoin(man_url, line))
if extra_query:
frag_url = update_url_query(frag_url, extra_query)
fragments.append({
'frag_index': frag_index,
'url': frag_url,
'decrypt_info': decrypt_info,
'byte_range': byte_range,
'media_sequence': media_sequence,
})
elif line.startswith('#EXT-X-MAP'):
if format_index and discontinuity_count != format_index:
continue
if frag_index > 0:
self.report_error(
'Initialization fragment found after media fragments, unable to download')
return False
frag_index += 1
map_info = parse_m3u8_attributes(line[11:])
frag_url = (
map_info.get('URI')
if re.match(r'^https?://', map_info.get('URI'))
else compat_urlparse.urljoin(man_url, map_info.get('URI')))
if extra_query:
frag_url = update_url_query(frag_url, extra_query)
fragments.append({
'frag_index': frag_index,
'url': frag_url,
'decrypt_info': decrypt_info,
'byte_range': byte_range,
'media_sequence': media_sequence
})
if map_info.get('BYTERANGE'):
splitted_byte_range = map_info.get('BYTERANGE').split('@')
sub_range_start = int(splitted_byte_range[1]) if len(splitted_byte_range) == 2 else byte_range['end']
byte_range = {
'start': sub_range_start,
'end': sub_range_start + int(splitted_byte_range[0]),
}
elif line.startswith('#EXT-X-KEY'):
decrypt_url = decrypt_info.get('URI')
decrypt_info = parse_m3u8_attributes(line[11:])
if decrypt_info['METHOD'] == 'AES-128':
if 'IV' in decrypt_info:
decrypt_info['IV'] = binascii.unhexlify(decrypt_info['IV'][2:].zfill(32))
if not re.match(r'^https?://', decrypt_info['URI']):
decrypt_info['URI'] = compat_urlparse.urljoin(
man_url, decrypt_info['URI'])
if extra_query:
decrypt_info['URI'] = update_url_query(decrypt_info['URI'], extra_query)
if decrypt_url != decrypt_info['URI']:
decrypt_info['KEY'] = None
elif line.startswith('#EXT-X-MEDIA-SEQUENCE'):
media_sequence = int(line[22:])
elif line.startswith('#EXT-X-BYTERANGE'):
splitted_byte_range = line[17:].split('@')
sub_range_start = int(splitted_byte_range[1]) if len(splitted_byte_range) == 2 else byte_range['end']
byte_range = {
'start': sub_range_start,
'end': sub_range_start + int(splitted_byte_range[0]),
}
elif is_ad_fragment_start(line):
ad_frag_next = True
elif is_ad_fragment_end(line):
ad_frag_next = False
elif line.startswith('#EXT-X-DISCONTINUITY'):
discontinuity_count += 1
i += 1
media_sequence += 1
# We only download the first fragment during the test
if self.params.get('test', False):
fragments = [fragments[0] if fragments else None]
if real_downloader:
info_copy = info_dict.copy()
info_copy['fragments'] = fragments
fd = real_downloader(self.ydl, self.params)
# TODO: Make progress updates work without hooking twice
# for ph in self._progress_hooks:
# fd.add_progress_hook(ph)
return fd.real_download(filename, info_copy)
if is_webvtt:
def pack_fragment(frag_content, frag_index):
output = io.StringIO()
adjust = 0
for block in webvtt.parse_fragment(frag_content):
if isinstance(block, webvtt.CueBlock):
block.start += adjust
block.end += adjust
dedup_window = extra_state.setdefault('webvtt_dedup_window', [])
cue = block.as_json
# skip the cue if an identical one appears
# in the window of potential duplicates
# and prune the window of unviable candidates
i = 0
skip = True
while i < len(dedup_window):
window_cue = dedup_window[i]
if window_cue == cue:
break
if window_cue['end'] >= cue['start']:
i += 1
continue
del dedup_window[i]
else:
skip = False
if skip:
continue
# add the cue to the window
dedup_window.append(cue)
elif isinstance(block, webvtt.Magic):
# take care of MPEG PES timestamp overflow
if block.mpegts is None:
block.mpegts = 0
extra_state.setdefault('webvtt_mpegts_adjust', 0)
block.mpegts += extra_state['webvtt_mpegts_adjust'] << 33
if block.mpegts < extra_state.get('webvtt_mpegts_last', 0):
extra_state['webvtt_mpegts_adjust'] += 1
block.mpegts += 1 << 33
extra_state['webvtt_mpegts_last'] = block.mpegts
if frag_index == 1:
extra_state['webvtt_mpegts'] = block.mpegts or 0
extra_state['webvtt_local'] = block.local or 0
# XXX: block.local = block.mpegts = None ?
else:
if block.mpegts is not None and block.local is not None:
adjust = (
(block.mpegts - extra_state.get('webvtt_mpegts', 0))
- (block.local - extra_state.get('webvtt_local', 0))
)
continue
elif isinstance(block, webvtt.HeaderBlock):
if frag_index != 1:
# XXX: this should probably be silent as well
# or verify that all segments contain the same data
self.report_warning(bug_reports_message(
'Discarding a %s block found in the middle of the stream; '
'if the subtitles display incorrectly,'
% (type(block).__name__)))
continue
block.write_into(output)
return output.getvalue().encode('utf-8')
else:
pack_fragment = None
return self.download_and_append_fragments(ctx, fragments, info_dict, pack_fragment)