[yt-dlp.git] / yt_dlp / downloader / ism.py

import binascii
import io
import struct
import time

from .fragment import FragmentFD
from ..compat import compat_urllib_error

u8 = struct.Struct('>B')
u88 = struct.Struct('>Bx')
u16 = struct.Struct('>H')
u1616 = struct.Struct('>Hxx')
u32 = struct.Struct('>I')
u64 = struct.Struct('>Q')

s88 = struct.Struct('>bx')
s16 = struct.Struct('>h')
s1616 = struct.Struct('>hxx')
s32 = struct.Struct('>i')

unity_matrix = (s32.pack(0x10000) + s32.pack(0) * 3) * 2 + s32.pack(0x40000000)

TRACK_ENABLED = 0x1
TRACK_IN_MOVIE = 0x2
TRACK_IN_PREVIEW = 0x4

SELF_CONTAINED = 0x1


def box(box_type, payload):
    return u32.pack(8 + len(payload)) + box_type + payload


def full_box(box_type, version, flags, payload):
    return box(box_type, u8.pack(version) + u32.pack(flags)[1:] + payload)


def write_piff_header(stream, params):
    track_id = params['track_id']
    fourcc = params['fourcc']
    duration = params['duration']
    timescale = params.get('timescale', 10000000)
    language = params.get('language', 'und')
    height = params.get('height', 0)
    width = params.get('width', 0)
    stream_type = params['stream_type']
    creation_time = modification_time = int(time.time())

    ftyp_payload = b'isml'  # major brand
    ftyp_payload += u32.pack(1)  # minor version
    ftyp_payload += b'piff' + b'iso2'  # compatible brands
    stream.write(box(b'ftyp', ftyp_payload))  # File Type Box

    mvhd_payload = u64.pack(creation_time)
    mvhd_payload += u64.pack(modification_time)
    mvhd_payload += u32.pack(timescale)
    mvhd_payload += u64.pack(duration)
    mvhd_payload += s1616.pack(1)  # rate
    mvhd_payload += s88.pack(1)  # volume
    mvhd_payload += u16.pack(0)  # reserved
    mvhd_payload += u32.pack(0) * 2  # reserved
    mvhd_payload += unity_matrix
    mvhd_payload += u32.pack(0) * 6  # pre defined
    mvhd_payload += u32.pack(0xffffffff)  # next track id
    moov_payload = full_box(b'mvhd', 1, 0, mvhd_payload)  # Movie Header Box

    tkhd_payload = u64.pack(creation_time)
    tkhd_payload += u64.pack(modification_time)
    tkhd_payload += u32.pack(track_id)  # track id
    tkhd_payload += u32.pack(0)  # reserved
    tkhd_payload += u64.pack(duration)
    tkhd_payload += u32.pack(0) * 2  # reserved
    tkhd_payload += s16.pack(0)  # layer
    tkhd_payload += s16.pack(0)  # alternate group
    tkhd_payload += s88.pack(1 if stream_type == 'audio' else 0)  # volume
    tkhd_payload += u16.pack(0)  # reserved
    tkhd_payload += unity_matrix
    tkhd_payload += u1616.pack(width)
    tkhd_payload += u1616.pack(height)
    trak_payload = full_box(b'tkhd', 1, TRACK_ENABLED | TRACK_IN_MOVIE | TRACK_IN_PREVIEW, tkhd_payload)  # Track Header Box

    mdhd_payload = u64.pack(creation_time)
    mdhd_payload += u64.pack(modification_time)
    mdhd_payload += u32.pack(timescale)
    mdhd_payload += u64.pack(duration)
    mdhd_payload += u16.pack(((ord(language[0]) - 0x60) << 10) | ((ord(language[1]) - 0x60) << 5) | (ord(language[2]) - 0x60))
    mdhd_payload += u16.pack(0)  # pre defined
    mdia_payload = full_box(b'mdhd', 1, 0, mdhd_payload)  # Media Header Box

    hdlr_payload = u32.pack(0)  # pre defined
    if stream_type == 'audio':  # handler type
        hdlr_payload += b'soun'
        hdlr_payload += u32.pack(0) * 3  # reserved
        hdlr_payload += b'SoundHandler\0'  # name
    elif stream_type == 'video':
        hdlr_payload += b'vide'
        hdlr_payload += u32.pack(0) * 3  # reserved
        hdlr_payload += b'VideoHandler\0'  # name
    elif stream_type == 'text':
        hdlr_payload += b'subt'
        hdlr_payload += u32.pack(0) * 3  # reserved
        hdlr_payload += b'SubtitleHandler\0'  # name
    else:
        assert False
    mdia_payload += full_box(b'hdlr', 0, 0, hdlr_payload)  # Handler Reference Box

    if stream_type == 'audio':
        smhd_payload = s88.pack(0)  # balance
        smhd_payload += u16.pack(0)  # reserved
        media_header_box = full_box(b'smhd', 0, 0, smhd_payload)  # Sound Media Header
    elif stream_type == 'video':
        vmhd_payload = u16.pack(0)  # graphics mode
        vmhd_payload += u16.pack(0) * 3  # opcolor
        media_header_box = full_box(b'vmhd', 0, 1, vmhd_payload)  # Video Media Header
    elif stream_type == 'text':
        media_header_box = full_box(b'sthd', 0, 0, b'')  # Subtitle Media Header
    else:
        assert False
    minf_payload = media_header_box

    dref_payload = u32.pack(1)  # entry count
    dref_payload += full_box(b'url ', 0, SELF_CONTAINED, b'')  # Data Entry URL Box
    dinf_payload = full_box(b'dref', 0, 0, dref_payload)  # Data Reference Box
    minf_payload += box(b'dinf', dinf_payload)  # Data Information Box

    stsd_payload = u32.pack(1)  # entry count

    sample_entry_payload = u8.pack(0) * 6  # reserved
    sample_entry_payload += u16.pack(1)  # data reference index
    if stream_type == 'audio':
        sample_entry_payload += u32.pack(0) * 2  # reserved
        sample_entry_payload += u16.pack(params.get('channels', 2))
        sample_entry_payload += u16.pack(params.get('bits_per_sample', 16))
        sample_entry_payload += u16.pack(0)  # pre defined
        sample_entry_payload += u16.pack(0)  # reserved
        sample_entry_payload += u1616.pack(params['sampling_rate'])

        if fourcc == 'AACL':
            sample_entry_box = box(b'mp4a', sample_entry_payload)
    elif stream_type == 'video':
        sample_entry_payload += u16.pack(0)  # pre defined
        sample_entry_payload += u16.pack(0)  # reserved
        sample_entry_payload += u32.pack(0) * 3  # pre defined
        sample_entry_payload += u16.pack(width)
        sample_entry_payload += u16.pack(height)
        sample_entry_payload += u1616.pack(0x48)  # horiz resolution 72 dpi
        sample_entry_payload += u1616.pack(0x48)  # vert resolution 72 dpi
        sample_entry_payload += u32.pack(0)  # reserved
        sample_entry_payload += u16.pack(1)  # frame count
        sample_entry_payload += u8.pack(0) * 32  # compressor name
        sample_entry_payload += u16.pack(0x18)  # depth
        sample_entry_payload += s16.pack(-1)  # pre defined

        codec_private_data = binascii.unhexlify(params['codec_private_data'].encode())
        if fourcc in ('H264', 'AVC1'):
            sps, pps = codec_private_data.split(u32.pack(1))[1:]
            avcc_payload = u8.pack(1)  # configuration version
            avcc_payload += sps[1:4]  # avc profile indication + profile compatibility + avc level indication
            avcc_payload += u8.pack(0xfc | (params.get('nal_unit_length_field', 4) - 1))  # complete representation (1) + reserved (11111) + length size minus one
            avcc_payload += u8.pack(1)  # reserved (0) + number of sps (0000001)
            avcc_payload += u16.pack(len(sps))
            avcc_payload += sps
            avcc_payload += u8.pack(1)  # number of pps
            avcc_payload += u16.pack(len(pps))
            avcc_payload += pps
            sample_entry_payload += box(b'avcC', avcc_payload)  # AVC Decoder Configuration Record
            sample_entry_box = box(b'avc1', sample_entry_payload)  # AVC Simple Entry
        else:
            assert False
    elif stream_type == 'text':
        if fourcc == 'TTML':
            sample_entry_payload += b'http://www.w3.org/ns/ttml\0'  # namespace
            sample_entry_payload += b'\0'  # schema location
            sample_entry_payload += b'\0'  # auxilary mime types(??)
            sample_entry_box = box(b'stpp', sample_entry_payload)
        else:
            assert False
    else:
        assert False
    stsd_payload += sample_entry_box

    stbl_payload = full_box(b'stsd', 0, 0, stsd_payload)  # Sample Description Box

    stts_payload = u32.pack(0)  # entry count
    stbl_payload += full_box(b'stts', 0, 0, stts_payload)  # Decoding Time to Sample Box

    stsc_payload = u32.pack(0)  # entry count
    stbl_payload += full_box(b'stsc', 0, 0, stsc_payload)  # Sample To Chunk Box

    stco_payload = u32.pack(0)  # entry count
    stbl_payload += full_box(b'stco', 0, 0, stco_payload)  # Chunk Offset Box

    minf_payload += box(b'stbl', stbl_payload)  # Sample Table Box

    mdia_payload += box(b'minf', minf_payload)  # Media Information Box

    trak_payload += box(b'mdia', mdia_payload)  # Media Box

    moov_payload += box(b'trak', trak_payload)  # Track Box

    mehd_payload = u64.pack(duration)
    mvex_payload = full_box(b'mehd', 1, 0, mehd_payload)  # Movie Extends Header Box

    trex_payload = u32.pack(track_id)  # track id
    trex_payload += u32.pack(1)  # default sample description index
    trex_payload += u32.pack(0)  # default sample duration
    trex_payload += u32.pack(0)  # default sample size
    trex_payload += u32.pack(0)  # default sample flags
    mvex_payload += full_box(b'trex', 0, 0, trex_payload)  # Track Extends Box

    moov_payload += box(b'mvex', mvex_payload)  # Movie Extends Box
    stream.write(box(b'moov', moov_payload))  # Movie Box


def extract_box_data(data, box_sequence):
    data_reader = io.BytesIO(data)
    while True:
        box_size = u32.unpack(data_reader.read(4))[0]
        box_type = data_reader.read(4)
        if box_type == box_sequence[0]:
            box_data = data_reader.read(box_size - 8)
            if len(box_sequence) == 1:
                return box_data
            return extract_box_data(box_data, box_sequence[1:])
        data_reader.seek(box_size - 8, 1)


class IsmFD(FragmentFD):
    """
    Download segments in a ISM manifest
    """

    FD_NAME = 'ism'

    def real_download(self, filename, info_dict):
        segments = info_dict['fragments'][:1] if self.params.get(
            'test', False) else info_dict['fragments']

        ctx = {
            'filename': filename,
            'total_frags': len(segments),
        }

        self._prepare_and_start_frag_download(ctx, info_dict)

        extra_state = ctx.setdefault('extra_state', {
            'ism_track_written': False,
        })

        fragment_retries = self.params.get('fragment_retries', 0)
        skip_unavailable_fragments = self.params.get('skip_unavailable_fragments', True)

        frag_index = 0
        for i, segment in enumerate(segments):
            frag_index += 1
            if frag_index <= ctx['fragment_index']:
                continue
            count = 0
            while count <= fragment_retries:
                try:
                    success = self._download_fragment(ctx, segment['url'], info_dict)
                    if not success:
                        return False
                    frag_content = self._read_fragment(ctx)

                    if not extra_state['ism_track_written']:
                        tfhd_data = extract_box_data(frag_content, [b'moof', b'traf', b'tfhd'])
                        info_dict['_download_params']['track_id'] = u32.unpack(tfhd_data[4:8])[0]
                        write_piff_header(ctx['dest_stream'], info_dict['_download_params'])
                        extra_state['ism_track_written'] = True
                    self._append_fragment(ctx, frag_content)
                    break
                except compat_urllib_error.HTTPError as err:
                    count += 1
                    if count <= fragment_retries:
                        self.report_retry_fragment(err, frag_index, count, fragment_retries)
            if count > fragment_retries:
                if skip_unavailable_fragments:
                    self.report_skip_fragment(frag_index)
                    continue
                self.report_error('giving up after %s fragment retries' % fragment_retries)
                return False

        self._finish_frag_download(ctx, info_dict)

        return True
Commit	Line	Data
b2758123 RA	1	import binascii
b2758123 RA	2	import io
f9934b96	3	import struct
f8271158	4	import time
b2758123 RA	5
b2758123 RA	6	from .fragment import FragmentFD
f8271158	7	from ..compat import compat_urllib_error
65220c3b	8
f9934b96	9	u8 = struct.Struct('>B')
	10	u88 = struct.Struct('>Bx')
	11	u16 = struct.Struct('>H')
	12	u1616 = struct.Struct('>Hxx')
	13	u32 = struct.Struct('>I')
	14	u64 = struct.Struct('>Q')
65220c3b	15
f9934b96	16	s88 = struct.Struct('>bx')
	17	s16 = struct.Struct('>h')
	18	s1616 = struct.Struct('>hxx')
	19	s32 = struct.Struct('>i')
b2758123 RA	20
	21	unity_matrix = (s32.pack(0x10000) + s32.pack(0) * 3) * 2 + s32.pack(0x40000000)
	22
	23	TRACK_ENABLED = 0x1
	24	TRACK_IN_MOVIE = 0x2
	25	TRACK_IN_PREVIEW = 0x4
	26
	27	SELF_CONTAINED = 0x1
	28
	29
	30	def box(box_type, payload):
	31	return u32.pack(8 + len(payload)) + box_type + payload
	32
	33
	34	def full_box(box_type, version, flags, payload):
	35	return box(box_type, u8.pack(version) + u32.pack(flags)[1:] + payload)
	36
	37
	38	def write_piff_header(stream, params):
	39	track_id = params['track_id']
	40	fourcc = params['fourcc']
	41	duration = params['duration']
	42	timescale = params.get('timescale', 10000000)
	43	language = params.get('language', 'und')
	44	height = params.get('height', 0)
	45	width = params.get('width', 0)
fd76a142	46	stream_type = params['stream_type']
b2758123 RA	47	creation_time = modification_time = int(time.time())
	48
	49	ftyp_payload = b'isml' # major brand
	50	ftyp_payload += u32.pack(1) # minor version
	51	ftyp_payload += b'piff' + b'iso2' # compatible brands
	52	stream.write(box(b'ftyp', ftyp_payload)) # File Type Box
	53
	54	mvhd_payload = u64.pack(creation_time)
	55	mvhd_payload += u64.pack(modification_time)
	56	mvhd_payload += u32.pack(timescale)
	57	mvhd_payload += u64.pack(duration)
	58	mvhd_payload += s1616.pack(1) # rate
	59	mvhd_payload += s88.pack(1) # volume
	60	mvhd_payload += u16.pack(0) # reserved
	61	mvhd_payload += u32.pack(0) * 2 # reserved
	62	mvhd_payload += unity_matrix
	63	mvhd_payload += u32.pack(0) * 6 # pre defined
	64	mvhd_payload += u32.pack(0xffffffff) # next track id
	65	moov_payload = full_box(b'mvhd', 1, 0, mvhd_payload) # Movie Header Box
	66
	67	tkhd_payload = u64.pack(creation_time)
	68	tkhd_payload += u64.pack(modification_time)
	69	tkhd_payload += u32.pack(track_id) # track id
	70	tkhd_payload += u32.pack(0) # reserved
	71	tkhd_payload += u64.pack(duration)
	72	tkhd_payload += u32.pack(0) * 2 # reserved
	73	tkhd_payload += s16.pack(0) # layer
	74	tkhd_payload += s16.pack(0) # alternate group
fd76a142	75	tkhd_payload += s88.pack(1 if stream_type == 'audio' else 0) # volume
b2758123 RA	76	tkhd_payload += u16.pack(0) # reserved
	77	tkhd_payload += unity_matrix
	78	tkhd_payload += u1616.pack(width)
	79	tkhd_payload += u1616.pack(height)
	80	trak_payload = full_box(b'tkhd', 1, TRACK_ENABLED \| TRACK_IN_MOVIE \| TRACK_IN_PREVIEW, tkhd_payload) # Track Header Box
	81
	82	mdhd_payload = u64.pack(creation_time)
	83	mdhd_payload += u64.pack(modification_time)
	84	mdhd_payload += u32.pack(timescale)
	85	mdhd_payload += u64.pack(duration)
	86	mdhd_payload += u16.pack(((ord(language[0]) - 0x60) << 10) \| ((ord(language[1]) - 0x60) << 5) \| (ord(language[2]) - 0x60))
	87	mdhd_payload += u16.pack(0) # pre defined
	88	mdia_payload = full_box(b'mdhd', 1, 0, mdhd_payload) # Media Header Box
	89
	90	hdlr_payload = u32.pack(0) # pre defined
fd76a142 F	91	if stream_type == 'audio': # handler type
	92	hdlr_payload += b'soun'
	93	hdlr_payload += u32.pack(0) * 3 # reserved
	94	hdlr_payload += b'SoundHandler\0' # name
	95	elif stream_type == 'video':
	96	hdlr_payload += b'vide'
	97	hdlr_payload += u32.pack(0) * 3 # reserved
	98	hdlr_payload += b'VideoHandler\0' # name
	99	elif stream_type == 'text':
	100	hdlr_payload += b'subt'
	101	hdlr_payload += u32.pack(0) * 3 # reserved
	102	hdlr_payload += b'SubtitleHandler\0' # name
	103	else:
	104	assert False
b2758123 RA	105	mdia_payload += full_box(b'hdlr', 0, 0, hdlr_payload) # Handler Reference Box
b2758123 RA	106
fd76a142	107	if stream_type == 'audio':
b2758123	108	smhd_payload = s88.pack(0) # balance
2583c0b5	109	smhd_payload += u16.pack(0) # reserved
b2758123	110	media_header_box = full_box(b'smhd', 0, 0, smhd_payload) # Sound Media Header
fd76a142	111	elif stream_type == 'video':
b2758123 RA	112	vmhd_payload = u16.pack(0) # graphics mode
	113	vmhd_payload += u16.pack(0) * 3 # opcolor
	114	media_header_box = full_box(b'vmhd', 0, 1, vmhd_payload) # Video Media Header
fd76a142	115	elif stream_type == 'text':
66a1b864	116	media_header_box = full_box(b'sthd', 0, 0, b'') # Subtitle Media Header
fd76a142 F	117	else:
fd76a142 F	118	assert False
b2758123 RA	119	minf_payload = media_header_box
	120
	121	dref_payload = u32.pack(1) # entry count
	122	dref_payload += full_box(b'url ', 0, SELF_CONTAINED, b'') # Data Entry URL Box
	123	dinf_payload = full_box(b'dref', 0, 0, dref_payload) # Data Reference Box
	124	minf_payload += box(b'dinf', dinf_payload) # Data Information Box
	125
	126	stsd_payload = u32.pack(1) # entry count
	127
	128	sample_entry_payload = u8.pack(0) * 6 # reserved
	129	sample_entry_payload += u16.pack(1) # data reference index
fd76a142	130	if stream_type == 'audio':
b2758123 RA	131	sample_entry_payload += u32.pack(0) * 2 # reserved
	132	sample_entry_payload += u16.pack(params.get('channels', 2))
	133	sample_entry_payload += u16.pack(params.get('bits_per_sample', 16))
	134	sample_entry_payload += u16.pack(0) # pre defined
	135	sample_entry_payload += u16.pack(0) # reserved
	136	sample_entry_payload += u1616.pack(params['sampling_rate'])
	137
	138	if fourcc == 'AACL':
9d64e1dc	139	sample_entry_box = box(b'mp4a', sample_entry_payload)
fd76a142	140	elif stream_type == 'video':
b2758123 RA	141	sample_entry_payload += u16.pack(0) # pre defined
	142	sample_entry_payload += u16.pack(0) # reserved
	143	sample_entry_payload += u32.pack(0) * 3 # pre defined
	144	sample_entry_payload += u16.pack(width)
	145	sample_entry_payload += u16.pack(height)
	146	sample_entry_payload += u1616.pack(0x48) # horiz resolution 72 dpi
	147	sample_entry_payload += u1616.pack(0x48) # vert resolution 72 dpi
	148	sample_entry_payload += u32.pack(0) # reserved
	149	sample_entry_payload += u16.pack(1) # frame count
	150	sample_entry_payload += u8.pack(0) * 32 # compressor name
	151	sample_entry_payload += u16.pack(0x18) # depth
	152	sample_entry_payload += s16.pack(-1) # pre defined
	153
0f06bcd7	154	codec_private_data = binascii.unhexlify(params['codec_private_data'].encode())
b2758123 RA	155	if fourcc in ('H264', 'AVC1'):
	156	sps, pps = codec_private_data.split(u32.pack(1))[1:]
	157	avcc_payload = u8.pack(1) # configuration version
10380e55	158	avcc_payload += sps[1:4] # avc profile indication + profile compatibility + avc level indication
843ad179	159	avcc_payload += u8.pack(0xfc \| (params.get('nal_unit_length_field', 4) - 1)) # complete representation (1) + reserved (11111) + length size minus one
b2758123 RA	160	avcc_payload += u8.pack(1) # reserved (0) + number of sps (0000001)
	161	avcc_payload += u16.pack(len(sps))
	162	avcc_payload += sps
	163	avcc_payload += u8.pack(1) # number of pps
	164	avcc_payload += u16.pack(len(pps))
	165	avcc_payload += pps
	166	sample_entry_payload += box(b'avcC', avcc_payload) # AVC Decoder Configuration Record
9d64e1dc	167	sample_entry_box = box(b'avc1', sample_entry_payload) # AVC Simple Entry
fd76a142 F	168	else:
fd76a142 F	169	assert False
66a1b864 F	170	elif stream_type == 'text':
	171	if fourcc == 'TTML':
	172	sample_entry_payload += b'http://www.w3.org/ns/ttml\0' # namespace
	173	sample_entry_payload += b'\0' # schema location
	174	sample_entry_payload += b'\0' # auxilary mime types(??)
	175	sample_entry_box = box(b'stpp', sample_entry_payload)
	176	else:
	177	assert False
fd76a142 F	178	else:
fd76a142 F	179	assert False
9d64e1dc	180	stsd_payload += sample_entry_box
b2758123 RA	181
	182	stbl_payload = full_box(b'stsd', 0, 0, stsd_payload) # Sample Description Box
	183
	184	stts_payload = u32.pack(0) # entry count
	185	stbl_payload += full_box(b'stts', 0, 0, stts_payload) # Decoding Time to Sample Box
	186
	187	stsc_payload = u32.pack(0) # entry count
	188	stbl_payload += full_box(b'stsc', 0, 0, stsc_payload) # Sample To Chunk Box
	189
	190	stco_payload = u32.pack(0) # entry count
	191	stbl_payload += full_box(b'stco', 0, 0, stco_payload) # Chunk Offset Box
	192
	193	minf_payload += box(b'stbl', stbl_payload) # Sample Table Box
	194
	195	mdia_payload += box(b'minf', minf_payload) # Media Information Box
	196
	197	trak_payload += box(b'mdia', mdia_payload) # Media Box
	198
	199	moov_payload += box(b'trak', trak_payload) # Track Box
	200
	201	mehd_payload = u64.pack(duration)
	202	mvex_payload = full_box(b'mehd', 1, 0, mehd_payload) # Movie Extends Header Box
	203
	204	trex_payload = u32.pack(track_id) # track id
	205	trex_payload += u32.pack(1) # default sample description index
	206	trex_payload += u32.pack(0) # default sample duration
	207	trex_payload += u32.pack(0) # default sample size
	208	trex_payload += u32.pack(0) # default sample flags
	209	mvex_payload += full_box(b'trex', 0, 0, trex_payload) # Track Extends Box
	210
	211	moov_payload += box(b'mvex', mvex_payload) # Movie Extends Box
	212	stream.write(box(b'moov', moov_payload)) # Movie Box
	213
	214
	215	def extract_box_data(data, box_sequence):
	216	data_reader = io.BytesIO(data)
	217	while True:
	218	box_size = u32.unpack(data_reader.read(4))[0]
	219	box_type = data_reader.read(4)
	220	if box_type == box_sequence[0]:
	221	box_data = data_reader.read(box_size - 8)
	222	if len(box_sequence) == 1:
	223	return box_data
	224	return extract_box_data(box_data, box_sequence[1:])
	225	data_reader.seek(box_size - 8, 1)
	226
	227
	228	class IsmFD(FragmentFD):
	229	"""
	230	Download segments in a ISM manifest
	231	"""
	232
	233	FD_NAME = 'ism'
	234
	235	def real_download(self, filename, info_dict):
	236	segments = info_dict['fragments'][:1] if self.params.get(
	237	'test', False) else info_dict['fragments']
	238
	239	ctx = {
	240	'filename': filename,
	241	'total_frags': len(segments),
	242	}
	243
3ba7740d	244	self._prepare_and_start_frag_download(ctx, info_dict)
b2758123	245
d4553567 F	246	extra_state = ctx.setdefault('extra_state', {
	247	'ism_track_written': False,
	248	})
	249
b2758123 RA	250	fragment_retries = self.params.get('fragment_retries', 0)
	251	skip_unavailable_fragments = self.params.get('skip_unavailable_fragments', True)
	252
75a24854	253	frag_index = 0
b2758123	254	for i, segment in enumerate(segments):
75a24854	255	frag_index += 1
3e0304fe	256	if frag_index <= ctx['fragment_index']:
75a24854	257	continue
b2758123 RA	258	count = 0
	259	while count <= fragment_retries:
	260	try:
d71fd412	261	success = self._download_fragment(ctx, segment['url'], info_dict)
b2758123 RA	262	if not success:
b2758123 RA	263	return False
d71fd412 LNO	264	frag_content = self._read_fragment(ctx)
d71fd412 LNO	265
d4553567	266	if not extra_state['ism_track_written']:
75a24854	267	tfhd_data = extract_box_data(frag_content, [b'moof', b'traf', b'tfhd'])
b2758123 RA	268	info_dict['_download_params']['track_id'] = u32.unpack(tfhd_data[4:8])[0]
b2758123 RA	269	write_piff_header(ctx['dest_stream'], info_dict['_download_params'])
d4553567	270	extra_state['ism_track_written'] = True
75a24854	271	self._append_fragment(ctx, frag_content)
b2758123 RA	272	break
	273	except compat_urllib_error.HTTPError as err:
	274	count += 1
	275	if count <= fragment_retries:
75a24854	276	self.report_retry_fragment(err, frag_index, count, fragment_retries)
b2758123 RA	277	if count > fragment_retries:
b2758123 RA	278	if skip_unavailable_fragments:
75a24854	279	self.report_skip_fragment(frag_index)
b2758123 RA	280	continue
	281	self.report_error('giving up after %s fragment retries' % fragment_retries)
	282	return False
	283
3ba7740d	284	self._finish_frag_download(ctx, info_dict)
b2758123	285
b2758123	286	return True