1
0
Fork 0
mirror of https://github.com/blackjack4494/yt-dlc.git synced 2024-12-23 08:17:00 +00:00
yt-dlc/youtube_dl/downloader/f4m.py
2015-02-17 21:44:41 +01:00

386 lines
12 KiB
Python

from __future__ import division, unicode_literals
import base64
import io
import itertools
import os
import time
import xml.etree.ElementTree as etree
from .common import FileDownloader
from .http import HttpFD
from ..compat import (
compat_urlparse,
)
from ..utils import (
struct_pack,
struct_unpack,
encodeFilename,
sanitize_open,
xpath_text,
)
class FlvReader(io.BytesIO):
"""
Reader for Flv files
The file format is documented in https://www.adobe.com/devnet/f4v.html
"""
# Utility functions for reading numbers and strings
def read_unsigned_long_long(self):
return struct_unpack('!Q', self.read(8))[0]
def read_unsigned_int(self):
return struct_unpack('!I', self.read(4))[0]
def read_unsigned_char(self):
return struct_unpack('!B', self.read(1))[0]
def read_string(self):
res = b''
while True:
char = self.read(1)
if char == b'\x00':
break
res += char
return res
def read_box_info(self):
"""
Read a box and return the info as a tuple: (box_size, box_type, box_data)
"""
real_size = size = self.read_unsigned_int()
box_type = self.read(4)
header_end = 8
if size == 1:
real_size = self.read_unsigned_long_long()
header_end = 16
return real_size, box_type, self.read(real_size - header_end)
def read_asrt(self):
# version
self.read_unsigned_char()
# flags
self.read(3)
quality_entry_count = self.read_unsigned_char()
# QualityEntryCount
for i in range(quality_entry_count):
self.read_string()
segment_run_count = self.read_unsigned_int()
segments = []
for i in range(segment_run_count):
first_segment = self.read_unsigned_int()
fragments_per_segment = self.read_unsigned_int()
segments.append((first_segment, fragments_per_segment))
return {
'segment_run': segments,
}
def read_afrt(self):
# version
self.read_unsigned_char()
# flags
self.read(3)
# time scale
self.read_unsigned_int()
quality_entry_count = self.read_unsigned_char()
# QualitySegmentUrlModifiers
for i in range(quality_entry_count):
self.read_string()
fragments_count = self.read_unsigned_int()
fragments = []
for i in range(fragments_count):
first = self.read_unsigned_int()
first_ts = self.read_unsigned_long_long()
duration = self.read_unsigned_int()
if duration == 0:
discontinuity_indicator = self.read_unsigned_char()
else:
discontinuity_indicator = None
fragments.append({
'first': first,
'ts': first_ts,
'duration': duration,
'discontinuity_indicator': discontinuity_indicator,
})
return {
'fragments': fragments,
}
def read_abst(self):
# version
self.read_unsigned_char()
# flags
self.read(3)
self.read_unsigned_int() # BootstrapinfoVersion
# Profile,Live,Update,Reserved
self.read(1)
# time scale
self.read_unsigned_int()
# CurrentMediaTime
self.read_unsigned_long_long()
# SmpteTimeCodeOffset
self.read_unsigned_long_long()
self.read_string() # MovieIdentifier
server_count = self.read_unsigned_char()
# ServerEntryTable
for i in range(server_count):
self.read_string()
quality_count = self.read_unsigned_char()
# QualityEntryTable
for i in range(quality_count):
self.read_string()
# DrmData
self.read_string()
# MetaData
self.read_string()
segments_count = self.read_unsigned_char()
segments = []
for i in range(segments_count):
box_size, box_type, box_data = self.read_box_info()
assert box_type == b'asrt'
segment = FlvReader(box_data).read_asrt()
segments.append(segment)
fragments_run_count = self.read_unsigned_char()
fragments = []
for i in range(fragments_run_count):
box_size, box_type, box_data = self.read_box_info()
assert box_type == b'afrt'
fragments.append(FlvReader(box_data).read_afrt())
return {
'segments': segments,
'fragments': fragments,
}
def read_bootstrap_info(self):
total_size, box_type, box_data = self.read_box_info()
assert box_type == b'abst'
return FlvReader(box_data).read_abst()
def read_bootstrap_info(bootstrap_bytes):
return FlvReader(bootstrap_bytes).read_bootstrap_info()
def build_fragments_list(boot_info):
""" Return a list of (segment, fragment) for each fragment in the video """
res = []
segment_run_table = boot_info['segments'][0]
fragment_run_entry_table = boot_info['fragments'][0]['fragments']
first_frag_number = fragment_run_entry_table[0]['first']
fragments_counter = itertools.count(first_frag_number)
for segment, fragments_count in segment_run_table['segment_run']:
for _ in range(fragments_count):
res.append((segment, next(fragments_counter)))
return res
def write_unsigned_int(stream, val):
stream.write(struct_pack('!I', val))
def write_unsigned_int_24(stream, val):
stream.write(struct_pack('!I', val)[1:])
def write_flv_header(stream):
"""Writes the FLV header to stream"""
# FLV header
stream.write(b'FLV\x01')
stream.write(b'\x05')
stream.write(b'\x00\x00\x00\x09')
stream.write(b'\x00\x00\x00\x00')
def write_metadata_tag(stream, metadata):
"""Writes optional metadata tag to stream"""
SCRIPT_TAG = b'\x12'
FLV_TAG_HEADER_LEN = 11
if metadata:
stream.write(SCRIPT_TAG)
write_unsigned_int_24(stream, len(metadata))
stream.write(b'\x00\x00\x00\x00\x00\x00\x00')
stream.write(metadata)
write_unsigned_int(stream, FLV_TAG_HEADER_LEN + len(metadata))
def _add_ns(prop):
return '{http://ns.adobe.com/f4m/1.0}%s' % prop
class HttpQuietDownloader(HttpFD):
def to_screen(self, *args, **kargs):
pass
class F4mFD(FileDownloader):
"""
A downloader for f4m manifests or AdobeHDS.
"""
def _get_unencrypted_media(self, doc):
media = doc.findall(_add_ns('media'))
if not media:
self.report_error('No media found')
for e in (doc.findall(_add_ns('drmAdditionalHeader')) +
doc.findall(_add_ns('drmAdditionalHeaderSet'))):
# If id attribute is missing it's valid for all media nodes
# without drmAdditionalHeaderId or drmAdditionalHeaderSetId attribute
if 'id' not in e.attrib:
self.report_error('Missing ID in f4m DRM')
media = list(filter(lambda e: 'drmAdditionalHeaderId' not in e.attrib and
'drmAdditionalHeaderSetId' not in e.attrib,
media))
if not media:
self.report_error('Unsupported DRM')
return media
def real_download(self, filename, info_dict):
man_url = info_dict['url']
requested_bitrate = info_dict.get('tbr')
self.to_screen('[download] Downloading f4m manifest')
manifest = self.ydl.urlopen(man_url).read()
doc = etree.fromstring(manifest)
formats = [(int(f.attrib.get('bitrate', -1)), f)
for f in self._get_unencrypted_media(doc)]
if requested_bitrate is None:
# get the best format
formats = sorted(formats, key=lambda f: f[0])
rate, media = formats[-1]
else:
rate, media = list(filter(
lambda f: int(f[0]) == requested_bitrate, formats))[0]
base_url = compat_urlparse.urljoin(man_url, media.attrib['url'])
bootstrap_node = doc.find(_add_ns('bootstrapInfo'))
if bootstrap_node.text is None:
bootstrap_url = compat_urlparse.urljoin(
base_url, bootstrap_node.attrib['url'])
bootstrap = self.ydl.urlopen(bootstrap_url).read()
else:
bootstrap = base64.b64decode(bootstrap_node.text)
metadata_node = media.find(_add_ns('metadata'))
if metadata_node is not None:
metadata = base64.b64decode(metadata_node.text)
else:
metadata = None
boot_info = read_bootstrap_info(bootstrap)
fragments_list = build_fragments_list(boot_info)
if self.params.get('test', False):
# We only download the first fragment
fragments_list = fragments_list[:1]
total_frags = len(fragments_list)
# For some akamai manifests we'll need to add a query to the fragment url
akamai_pv = xpath_text(doc, _add_ns('pv-2.0'))
self.report_destination(filename)
http_dl = HttpQuietDownloader(
self.ydl,
{
'continuedl': True,
'quiet': True,
'noprogress': True,
'ratelimit': self.params.get('ratelimit', None),
'test': self.params.get('test', False),
}
)
tmpfilename = self.temp_name(filename)
(dest_stream, tmpfilename) = sanitize_open(tmpfilename, 'wb')
write_flv_header(dest_stream)
write_metadata_tag(dest_stream, metadata)
# This dict stores the download progress, it's updated by the progress
# hook
state = {
'status': 'downloading',
'downloaded_bytes': 0,
'frag_index': 0,
'frag_count': total_frags,
'filename': filename,
'tmpfilename': tmpfilename,
}
start = time.time()
def frag_progress_hook(s):
if s['status'] not in ('downloading', 'finished'):
return
frag_total_bytes = s.get('total_bytes', 0)
if s['status'] == 'finished':
state['downloaded_bytes'] += frag_total_bytes
state['frag_index'] += 1
estimated_size = (
(state['downloaded_bytes'] + frag_total_bytes)
/ (state['frag_index'] + 1) * total_frags)
time_now = time.time()
state['total_bytes_estimate'] = estimated_size
state['elapsed'] = time_now - start
if s['status'] == 'finished':
progress = self.calc_percent(state['frag_index'], total_frags)
else:
frag_downloaded_bytes = s['downloaded_bytes']
frag_progress = self.calc_percent(frag_downloaded_bytes,
frag_total_bytes)
progress = self.calc_percent(state['frag_index'], total_frags)
progress += frag_progress / float(total_frags)
state['eta'] = self.calc_eta(
start, time_now, estimated_size, state['downloaded_bytes'] + frag_downloaded_bytes)
state['speed'] = s.get('speed')
self._hook_progress(state)
http_dl.add_progress_hook(frag_progress_hook)
frags_filenames = []
for (seg_i, frag_i) in fragments_list:
name = 'Seg%d-Frag%d' % (seg_i, frag_i)
url = base_url + name
if akamai_pv:
url += '?' + akamai_pv.strip(';')
frag_filename = '%s-%s' % (tmpfilename, name)
success = http_dl.download(frag_filename, {'url': url})
if not success:
return False
with open(frag_filename, 'rb') as down:
down_data = down.read()
reader = FlvReader(down_data)
while True:
_, box_type, box_data = reader.read_box_info()
if box_type == b'mdat':
dest_stream.write(box_data)
break
frags_filenames.append(frag_filename)
dest_stream.close()
elapsed = time.time() - start
self.try_rename(tmpfilename, filename)
for frag_file in frags_filenames:
os.remove(frag_file)
fsize = os.path.getsize(encodeFilename(filename))
self._hook_progress({
'downloaded_bytes': fsize,
'total_bytes': fsize,
'filename': filename,
'status': 'finished',
'elapsed': elapsed,
})
return True