mirror of
https://github.com/yt-dlp/yt-dlp.git
synced 2024-11-22 02:15:12 +00:00
[downloader/hls] Assemble single-file WebVTT subtitles from HLS segments
This commit is contained in:
Felix S
parent
5fbcebed8c
commit
4a2f19abbd
4 changed files with 432 additions and 0 deletions
|
|
@ -3018,10 +3018,24 @@ def compat_ctypes_WINFUNCTYPE(*args, **kwargs):
|
|||
return ctypes.WINFUNCTYPE(*args, **kwargs)
|
||||
|
||||
|
||||
try:
|
||||
compat_Pattern = re.Pattern
|
||||
except AttributeError:
|
||||
compat_Pattern = type(re.compile(''))
|
||||
|
||||
|
||||
try:
|
||||
compat_Match = re.Match
|
||||
except AttributeError:
|
||||
compat_Match = type(re.compile('').match(''))
|
||||
|
||||
|
||||
__all__ = [
|
||||
'compat_HTMLParseError',
|
||||
'compat_HTMLParser',
|
||||
'compat_HTTPError',
|
||||
'compat_Match',
|
||||
'compat_Pattern',
|
||||
'compat_Struct',
|
||||
'compat_b64decode',
|
||||
'compat_basestring',
|
||||
|
|
|
|||
|
|
@ -2,6 +2,7 @@
|
|||
|
||||
import errno
|
||||
import re
|
||||
import io
|
||||
import binascii
|
||||
try:
|
||||
from Crypto.Cipher import AES
|
||||
|
|
@ -27,7 +28,9 @@
|
|||
parse_m3u8_attributes,
|
||||
sanitize_open,
|
||||
update_url_query,
|
||||
bug_reports_message,
|
||||
)
|
||||
from .. import webvtt
|
||||
|
||||
|
||||
class HlsFD(FragmentFD):
|
||||
|
|
@ -78,6 +81,8 @@ def real_download(self, filename, info_dict):
|
|||
man_url = info_dict['url']
|
||||
self.to_screen('[%s] Downloading m3u8 manifest' % self.FD_NAME)
|
||||
|
||||
is_webvtt = info_dict['ext'] == 'vtt'
|
||||
|
||||
urlh = self.ydl.urlopen(self._prepare_url(info_dict, man_url))
|
||||
man_url = urlh.geturl()
|
||||
s = urlh.read().decode('utf-8', 'ignore')
|
||||
|
|
@ -142,6 +147,8 @@ def is_ad_fragment_end(s):
|
|||
else:
|
||||
self._prepare_and_start_frag_download(ctx)
|
||||
|
||||
extra_state = ctx.setdefault('extra_state', {})
|
||||
|
||||
fragment_retries = self.params.get('fragment_retries', 0)
|
||||
skip_unavailable_fragments = self.params.get('skip_unavailable_fragments', True)
|
||||
test = self.params.get('test', False)
|
||||
|
|
@ -308,6 +315,42 @@ def download_fragment(fragment):
|
|||
|
||||
return frag_content, frag_index
|
||||
|
||||
pack_fragment = lambda frag_content, _: frag_content
|
||||
|
||||
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
|
||||
elif isinstance(block, webvtt.Magic):
|
||||
# XXX: we do not handle MPEGTS overflow
|
||||
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')
|
||||
|
||||
def append_fragment(frag_content, frag_index):
|
||||
if frag_content:
|
||||
fragment_filename = '%s-Frag%d' % (ctx['tmpfilename'], frag_index)
|
||||
|
|
@ -315,6 +358,7 @@ def append_fragment(frag_content, frag_index):
|
|||
file, frag_sanitized = sanitize_open(fragment_filename, 'rb')
|
||||
ctx['fragment_filename_sanitized'] = frag_sanitized
|
||||
file.close()
|
||||
frag_content = pack_fragment(frag_content, frag_index)
|
||||
self._append_fragment(ctx, frag_content)
|
||||
return True
|
||||
except EnvironmentError as ose:
|
||||
|
|
|
|||
|
|
@ -2035,6 +2035,12 @@ def extract_media(x_media_line):
|
|||
'url': url,
|
||||
'ext': determine_ext(url),
|
||||
}
|
||||
if sub_info['ext'] == 'm3u8':
|
||||
# Per RFC 8216 §3.1, the only possible subtitle format m3u8
|
||||
# files may contain is WebVTT:
|
||||
# <https://tools.ietf.org/html/rfc8216#section-3.1>
|
||||
sub_info['ext'] = 'vtt'
|
||||
sub_info['protocol'] = 'm3u8_native'
|
||||
subtitles.setdefault(lang, []).append(sub_info)
|
||||
if media_type not in ('VIDEO', 'AUDIO'):
|
||||
return
|
||||
|
|
|
|||
368
yt_dlp/webvtt.py
Normal file
368
yt_dlp/webvtt.py
Normal file
|
|
@ -0,0 +1,368 @@
|
|||
# coding: utf-8
|
||||
from __future__ import unicode_literals, print_function, division
|
||||
|
||||
"""
|
||||
A partial parser for WebVTT segments. Interprets enough of the WebVTT stream
|
||||
to be able to assemble a single stand-alone subtitle file, suitably adjusting
|
||||
timestamps on the way, while everything else is passed through unmodified.
|
||||
|
||||
Regular expressions based on the W3C WebVTT specification
|
||||
<https://www.w3.org/TR/webvtt1/>. The X-TIMESTAMP-MAP extension is described
|
||||
in RFC 8216 §3.5 <https://tools.ietf.org/html/rfc8216#section-3.5>.
|
||||
"""
|
||||
|
||||
import re
|
||||
import io
|
||||
from .utils import int_or_none
|
||||
from .compat import (
|
||||
compat_str as str,
|
||||
compat_Pattern,
|
||||
compat_Match,
|
||||
)
|
||||
|
||||
|
||||
class _MatchParser(object):
|
||||
"""
|
||||
An object that maintains the current parsing position and allows
|
||||
conveniently advancing it as syntax elements are successfully parsed.
|
||||
"""
|
||||
|
||||
def __init__(self, string):
|
||||
self._data = string
|
||||
self._pos = 0
|
||||
|
||||
def match(self, r):
|
||||
if isinstance(r, compat_Pattern):
|
||||
return r.match(self._data, self._pos)
|
||||
if isinstance(r, str):
|
||||
if self._data.startswith(r, self._pos):
|
||||
return len(r)
|
||||
return None
|
||||
raise ValueError(r)
|
||||
|
||||
def advance(self, by):
|
||||
if by is None:
|
||||
amt = 0
|
||||
elif isinstance(by, compat_Match):
|
||||
amt = len(by.group(0))
|
||||
elif isinstance(by, str):
|
||||
amt = len(by)
|
||||
elif isinstance(by, int):
|
||||
amt = by
|
||||
else:
|
||||
raise ValueError(by)
|
||||
self._pos += amt
|
||||
return by
|
||||
|
||||
def consume(self, r):
|
||||
return self.advance(self.match(r))
|
||||
|
||||
def child(self):
|
||||
return _MatchChildParser(self)
|
||||
|
||||
|
||||
class _MatchChildParser(_MatchParser):
|
||||
"""
|
||||
A child parser state, which advances through the same data as
|
||||
its parent, but has an independent position. This is useful when
|
||||
advancing through syntax elements we might later want to backtrack
|
||||
from.
|
||||
"""
|
||||
|
||||
def __init__(self, parent):
|
||||
super(_MatchChildParser, self).__init__(parent._data)
|
||||
self.__parent = parent
|
||||
self._pos = parent._pos
|
||||
|
||||
def commit(self):
|
||||
"""
|
||||
Advance the parent state to the current position of this child state.
|
||||
"""
|
||||
self.__parent._pos = self._pos
|
||||
return self.__parent
|
||||
|
||||
|
||||
class ParseError(Exception):
|
||||
def __init__(self, parser):
|
||||
super(ParseError, self).__init__("Parse error at position %u (near %r)" % (
|
||||
parser._pos, parser._data[parser._pos:parser._pos + 20]
|
||||
))
|
||||
|
||||
|
||||
_REGEX_TS = re.compile(r'''(?x)
|
||||
(?:([0-9]{2,}):)?
|
||||
([0-9]{2}):
|
||||
([0-9]{2})\.
|
||||
([0-9]{3})?
|
||||
''')
|
||||
_REGEX_EOF = re.compile(r'\Z')
|
||||
_REGEX_NL = re.compile(r'(?:\r\n|[\r\n])')
|
||||
_REGEX_BLANK = re.compile(r'(?:\r\n|[\r\n])+')
|
||||
|
||||
|
||||
def _parse_ts(ts):
|
||||
"""
|
||||
Convert a parsed WebVTT timestamp (a re.Match obtained from _REGEX_TS)
|
||||
into an MPEG PES timestamp: a tick counter at 90 kHz resolution.
|
||||
"""
|
||||
|
||||
h, min, s, ms = ts.groups()
|
||||
return 90 * (
|
||||
int(h or 0) * 3600000 + # noqa: W504,E221,E222
|
||||
int(min) * 60000 + # noqa: W504,E221,E222
|
||||
int(s) * 1000 + # noqa: W504,E221,E222
|
||||
int(ms) # noqa: W504,E221,E222
|
||||
)
|
||||
|
||||
|
||||
def _format_ts(ts):
|
||||
"""
|
||||
Convert an MPEG PES timestamp into a WebVTT timestamp.
|
||||
This will lose sub-millisecond precision.
|
||||
"""
|
||||
|
||||
ts = int((ts + 45) // 90)
|
||||
ms , ts = divmod(ts, 1000) # noqa: W504,E221,E222,E203
|
||||
s , ts = divmod(ts, 60) # noqa: W504,E221,E222,E203
|
||||
min, h = divmod(ts, 60) # noqa: W504,E221,E222
|
||||
return '%02u:%02u:%02u.%03u' % (h, min, s, ms)
|
||||
|
||||
|
||||
class Block(object):
|
||||
"""
|
||||
An abstract WebVTT block.
|
||||
"""
|
||||
|
||||
def __init__(self, **kwargs):
|
||||
for key, val in kwargs.items():
|
||||
setattr(self, key, val)
|
||||
|
||||
@classmethod
|
||||
def parse(cls, parser):
|
||||
m = parser.match(cls._REGEX)
|
||||
if not m:
|
||||
return None
|
||||
parser.advance(m)
|
||||
return cls(raw=m.group(0))
|
||||
|
||||
def write_into(self, stream):
|
||||
stream.write(self.raw)
|
||||
|
||||
|
||||
class HeaderBlock(Block):
|
||||
"""
|
||||
A WebVTT block that may only appear in the header part of the file,
|
||||
i.e. before any cue blocks.
|
||||
"""
|
||||
|
||||
pass
|
||||
|
||||
|
||||
class Magic(HeaderBlock):
|
||||
_REGEX = re.compile(r'\ufeff?WEBVTT([ \t][^\r\n]*)?(?:\r\n|[\r\n])')
|
||||
|
||||
# XXX: The X-TIMESTAMP-MAP extension is described in RFC 8216 §3.5
|
||||
# <https://tools.ietf.org/html/rfc8216#section-3.5>, but the RFC
|
||||
# doesn’t specify the exact grammar nor where in the WebVTT
|
||||
# syntax it should be placed; the below has been devised based
|
||||
# on usage in the wild
|
||||
#
|
||||
# And strictly speaking, the presence of this extension violates
|
||||
# the W3C WebVTT spec. Oh well.
|
||||
|
||||
_REGEX_TSMAP = re.compile(r'X-TIMESTAMP-MAP=')
|
||||
_REGEX_TSMAP_LOCAL = re.compile(r'LOCAL:')
|
||||
_REGEX_TSMAP_MPEGTS = re.compile(r'MPEGTS:([0-9]+)')
|
||||
|
||||
@classmethod
|
||||
def __parse_tsmap(cls, parser):
|
||||
parser = parser.child()
|
||||
|
||||
while True:
|
||||
m = parser.consume(cls._REGEX_TSMAP_LOCAL)
|
||||
if m:
|
||||
m = parser.consume(_REGEX_TS)
|
||||
if m is None:
|
||||
raise ParseError(parser)
|
||||
local = _parse_ts(m)
|
||||
if local is None:
|
||||
raise ParseError(parser)
|
||||
else:
|
||||
m = parser.consume(cls._REGEX_TSMAP_MPEGTS)
|
||||
if m:
|
||||
mpegts = int_or_none(m.group(1))
|
||||
if mpegts is None:
|
||||
raise ParseError(parser)
|
||||
else:
|
||||
raise ParseError(parser)
|
||||
if parser.consume(','):
|
||||
continue
|
||||
if parser.consume(_REGEX_NL):
|
||||
break
|
||||
raise ParseError(parser)
|
||||
|
||||
parser.commit()
|
||||
return local, mpegts
|
||||
|
||||
@classmethod
|
||||
def parse(cls, parser):
|
||||
parser = parser.child()
|
||||
|
||||
m = parser.consume(cls._REGEX)
|
||||
if not m:
|
||||
raise ParseError(parser)
|
||||
|
||||
extra = m.group(1)
|
||||
local, mpegts = None, None
|
||||
if parser.consume(cls._REGEX_TSMAP):
|
||||
local, mpegts = cls.__parse_tsmap(parser)
|
||||
if not parser.consume(_REGEX_NL):
|
||||
raise ParseError(parser)
|
||||
parser.commit()
|
||||
return cls(extra=extra, mpegts=mpegts, local=local)
|
||||
|
||||
def write_into(self, stream):
|
||||
stream.write('WEBVTT')
|
||||
if self.extra is not None:
|
||||
stream.write(self.extra)
|
||||
stream.write('\n')
|
||||
if self.local or self.mpegts:
|
||||
stream.write('X-TIMESTAMP-MAP=LOCAL:')
|
||||
stream.write(_format_ts(self.local if self.local is not None else 0))
|
||||
stream.write(',MPEGTS:')
|
||||
stream.write(str(self.mpegts if self.mpegts is not None else 0))
|
||||
stream.write('\n')
|
||||
stream.write('\n')
|
||||
|
||||
|
||||
class StyleBlock(HeaderBlock):
|
||||
_REGEX = re.compile(r'''(?x)
|
||||
STYLE[\ \t]*(?:\r\n|[\r\n])
|
||||
((?:(?!-->)[^\r\n])+(?:\r\n|[\r\n]))*
|
||||
(?:\r\n|[\r\n])
|
||||
''')
|
||||
|
||||
|
||||
class RegionBlock(HeaderBlock):
|
||||
_REGEX = re.compile(r'''(?x)
|
||||
REGION[\ \t]*
|
||||
((?:(?!-->)[^\r\n])+(?:\r\n|[\r\n]))*
|
||||
(?:\r\n|[\r\n])
|
||||
''')
|
||||
|
||||
|
||||
class CommentBlock(Block):
|
||||
_REGEX = re.compile(r'''(?x)
|
||||
NOTE(?:\r\n|[\ \t\r\n])
|
||||
((?:(?!-->)[^\r\n])+(?:\r\n|[\r\n]))*
|
||||
(?:\r\n|[\r\n])
|
||||
''')
|
||||
|
||||
|
||||
class CueBlock(Block):
|
||||
"""
|
||||
A cue block. The payload is not interpreted.
|
||||
"""
|
||||
|
||||
_REGEX_ID = re.compile(r'((?:(?!-->)[^\r\n])+)(?:\r\n|[\r\n])')
|
||||
_REGEX_ARROW = re.compile(r'[ \t]+-->[ \t]+')
|
||||
_REGEX_SETTINGS = re.compile(r'[ \t]+((?:(?!-->)[^\r\n])+)')
|
||||
_REGEX_PAYLOAD = re.compile(r'[^\r\n]+(?:\r\n|[\r\n])?')
|
||||
|
||||
@classmethod
|
||||
def parse(cls, parser):
|
||||
parser = parser.child()
|
||||
|
||||
id = None
|
||||
m = parser.consume(cls._REGEX_ID)
|
||||
if m:
|
||||
id = m.group(1)
|
||||
|
||||
m0 = parser.consume(_REGEX_TS)
|
||||
if not m0:
|
||||
return None
|
||||
if not parser.consume(cls._REGEX_ARROW):
|
||||
return None
|
||||
m1 = parser.consume(_REGEX_TS)
|
||||
if not m1:
|
||||
return None
|
||||
m2 = parser.consume(cls._REGEX_SETTINGS)
|
||||
if not parser.consume(_REGEX_NL):
|
||||
return None
|
||||
|
||||
start = _parse_ts(m0)
|
||||
end = _parse_ts(m1)
|
||||
settings = m2.group(1) if m2 is not None else None
|
||||
|
||||
text = io.StringIO()
|
||||
while True:
|
||||
m = parser.consume(cls._REGEX_PAYLOAD)
|
||||
if not m:
|
||||
break
|
||||
text.write(m.group(0))
|
||||
|
||||
parser.commit()
|
||||
return cls(
|
||||
id=id,
|
||||
start=start, end=end, settings=settings,
|
||||
text=text.getvalue()
|
||||
)
|
||||
|
||||
def write_into(self, stream):
|
||||
if self.id is not None:
|
||||
stream.write(self.id)
|
||||
stream.write('\n')
|
||||
stream.write(_format_ts(self.start))
|
||||
stream.write(' --> ')
|
||||
stream.write(_format_ts(self.end))
|
||||
if self.settings is not None:
|
||||
stream.write(' ')
|
||||
stream.write(self.settings)
|
||||
stream.write('\n')
|
||||
stream.write(self.text)
|
||||
stream.write('\n')
|
||||
|
||||
|
||||
def parse_fragment(frag_content):
|
||||
"""
|
||||
A generator that yields (partially) parsed WebVTT blocks when given
|
||||
a bytes object containing the raw contents of a WebVTT file.
|
||||
"""
|
||||
|
||||
parser = _MatchParser(frag_content.decode('utf-8'))
|
||||
|
||||
yield Magic.parse(parser)
|
||||
|
||||
while not parser.match(_REGEX_EOF):
|
||||
if parser.consume(_REGEX_BLANK):
|
||||
continue
|
||||
|
||||
block = RegionBlock.parse(parser)
|
||||
if block:
|
||||
yield block
|
||||
continue
|
||||
block = StyleBlock.parse(parser)
|
||||
if block:
|
||||
yield block
|
||||
continue
|
||||
block = CommentBlock.parse(parser)
|
||||
if block:
|
||||
yield block # XXX: or skip
|
||||
continue
|
||||
|
||||
break
|
||||
|
||||
while not parser.match(_REGEX_EOF):
|
||||
if parser.consume(_REGEX_BLANK):
|
||||
continue
|
||||
|
||||
block = CommentBlock.parse(parser)
|
||||
if block:
|
||||
yield block # XXX: or skip
|
||||
continue
|
||||
block = CueBlock.parse(parser)
|
||||
if block:
|
||||
yield block
|
||||
continue
|
||||
|
||||
raise ParseError(parser)
|
||||
Loading…
Reference in a new issue