track custom youtube-dl distribution

11 files changed, 2668 insertions, 0 deletions

diff --git a/youtube_dl/downloader/__init__.py b/youtube_dl/downloader/__init__.py
new file mode 100644
index 0000000..2e485df
--- /dev/null
+++ b/youtube_dl/downloader/__init__.py
@@ -0,0 +1,61 @@
+from __future__ import unicode_literals
+
+from .common import FileDownloader
+from .f4m import F4mFD
+from .hls import HlsFD
+from .http import HttpFD
+from .rtmp import RtmpFD
+from .dash import DashSegmentsFD
+from .rtsp import RtspFD
+from .ism import IsmFD
+from .external import (
+    get_external_downloader,
+    FFmpegFD,
+)
+
+from ..utils import (
+    determine_protocol,
+)
+
+PROTOCOL_MAP = {
+    'rtmp': RtmpFD,
+    'm3u8_native': HlsFD,
+    'm3u8': FFmpegFD,
+    'mms': RtspFD,
+    'rtsp': RtspFD,
+    'f4m': F4mFD,
+    'http_dash_segments': DashSegmentsFD,
+    'ism': IsmFD,
+}
+
+
+def get_suitable_downloader(info_dict, params={}):
+    """Get the downloader class that can handle the info dict."""
+    protocol = determine_protocol(info_dict)
+    info_dict['protocol'] = protocol
+
+    # if (info_dict.get('start_time') or info_dict.get('end_time')) and not info_dict.get('requested_formats') and FFmpegFD.can_download(info_dict):
+    #     return FFmpegFD
+
+    external_downloader = params.get('external_downloader')
+    if external_downloader is not None:
+        ed = get_external_downloader(external_downloader)
+        if ed.can_download(info_dict):
+            return ed
+
+    if protocol.startswith('m3u8') and info_dict.get('is_live'):
+        return FFmpegFD
+
+    if protocol == 'm3u8' and params.get('hls_prefer_native') is True:
+        return HlsFD
+
+    if protocol == 'm3u8_native' and params.get('hls_prefer_native') is False:
+        return FFmpegFD
+
+    return PROTOCOL_MAP.get(protocol, HttpFD)
+
+
+__all__ = [
+    'get_suitable_downloader',
+    'FileDownloader',
+]
diff --git a/youtube_dl/downloader/common.py b/youtube_dl/downloader/common.py
new file mode 100644
index 0000000..5979833
--- /dev/null
+++ b/youtube_dl/downloader/common.py
@@ -0,0 +1,389 @@
+from __future__ import division, unicode_literals
+
+import os
+import re
+import sys
+import time
+import random
+
+from ..compat import compat_os_name
+from ..utils import (
+    decodeArgument,
+    encodeFilename,
+    error_to_compat_str,
+    format_bytes,
+    shell_quote,
+    timeconvert,
+)
+
+
+class FileDownloader(object):
+    """File Downloader class.
+
+    File downloader objects are the ones responsible of downloading the
+    actual video file and writing it to disk.
+
+    File downloaders accept a lot of parameters. In order not to saturate
+    the object constructor with arguments, it receives a dictionary of
+    options instead.
+
+    Available options:
+
+    verbose:            Print additional info to stdout.
+    quiet:              Do not print messages to stdout.
+    ratelimit:          Download speed limit, in bytes/sec.
+    retries:            Number of times to retry for HTTP error 5xx
+    buffersize:         Size of download buffer in bytes.
+    noresizebuffer:     Do not automatically resize the download buffer.
+    continuedl:         Try to continue downloads if possible.
+    noprogress:         Do not print the progress bar.
+    logtostderr:        Log messages to stderr instead of stdout.
+    consoletitle:       Display progress in console window's titlebar.
+    nopart:             Do not use temporary .part files.
+    updatetime:         Use the Last-modified header to set output file timestamps.
+    test:               Download only first bytes to test the downloader.
+    min_filesize:       Skip files smaller than this size
+    max_filesize:       Skip files larger than this size
+    xattr_set_filesize: Set ytdl.filesize user xattribute with expected size.
+    external_downloader_args:  A list of additional command-line arguments for the
+                        external downloader.
+    hls_use_mpegts:     Use the mpegts container for HLS videos.
+    http_chunk_size:    Size of a chunk for chunk-based HTTP downloading. May be
+                        useful for bypassing bandwidth throttling imposed by
+                        a webserver (experimental)
+
+    Subclasses of this one must re-define the real_download method.
+    """
+
+    _TEST_FILE_SIZE = 10241
+    params = None
+
+    def __init__(self, ydl, params):
+        """Create a FileDownloader object with the given options."""
+        self.ydl = ydl
+        self._progress_hooks = []
+        self.params = params
+        self.add_progress_hook(self.report_progress)
+
+    @staticmethod
+    def format_seconds(seconds):
+        (mins, secs) = divmod(seconds, 60)
+        (hours, mins) = divmod(mins, 60)
+        if hours > 99:
+            return '--:--:--'
+        if hours == 0:
+            return '%02d:%02d' % (mins, secs)
+        else:
+            return '%02d:%02d:%02d' % (hours, mins, secs)
+
+    @staticmethod
+    def calc_percent(byte_counter, data_len):
+        if data_len is None:
+            return None
+        return float(byte_counter) / float(data_len) * 100.0
+
+    @staticmethod
+    def format_percent(percent):
+        if percent is None:
+            return '---.-%'
+        return '%6s' % ('%3.1f%%' % percent)
+
+    @staticmethod
+    def calc_eta(start, now, total, current):
+        if total is None:
+            return None
+        if now is None:
+            now = time.time()
+        dif = now - start
+        if current == 0 or dif < 0.001:  # One millisecond
+            return None
+        rate = float(current) / dif
+        return int((float(total) - float(current)) / rate)
+
+    @staticmethod
+    def format_eta(eta):
+        if eta is None:
+            return '--:--'
+        return FileDownloader.format_seconds(eta)
+
+    @staticmethod
+    def calc_speed(start, now, bytes):
+        dif = now - start
+        if bytes == 0 or dif < 0.001:  # One millisecond
+            return None
+        return float(bytes) / dif
+
+    @staticmethod
+    def format_speed(speed):
+        if speed is None:
+            return '%10s' % '---b/s'
+        return '%10s' % ('%s/s' % format_bytes(speed))
+
+    @staticmethod
+    def format_retries(retries):
+        return 'inf' if retries == float('inf') else '%.0f' % retries
+
+    @staticmethod
+    def best_block_size(elapsed_time, bytes):
+        new_min = max(bytes / 2.0, 1.0)
+        new_max = min(max(bytes * 2.0, 1.0), 4194304)  # Do not surpass 4 MB
+        if elapsed_time < 0.001:
+            return int(new_max)
+        rate = bytes / elapsed_time
+        if rate > new_max:
+            return int(new_max)
+        if rate < new_min:
+            return int(new_min)
+        return int(rate)
+
+    @staticmethod
+    def parse_bytes(bytestr):
+        """Parse a string indicating a byte quantity into an integer."""
+        matchobj = re.match(r'(?i)^(\d+(?:\.\d+)?)([kMGTPEZY]?)$', bytestr)
+        if matchobj is None:
+            return None
+        number = float(matchobj.group(1))
+        multiplier = 1024.0 ** 'bkmgtpezy'.index(matchobj.group(2).lower())
+        return int(round(number * multiplier))
+
+    def to_screen(self, *args, **kargs):
+        self.ydl.to_screen(*args, **kargs)
+
+    def to_stderr(self, message):
+        self.ydl.to_screen(message)
+
+    def to_console_title(self, message):
+        self.ydl.to_console_title(message)
+
+    def trouble(self, *args, **kargs):
+        self.ydl.trouble(*args, **kargs)
+
+    def report_warning(self, *args, **kargs):
+        self.ydl.report_warning(*args, **kargs)
+
+    def report_error(self, *args, **kargs):
+        self.ydl.report_error(*args, **kargs)
+
+    def slow_down(self, start_time, now, byte_counter):
+        """Sleep if the download speed is over the rate limit."""
+        rate_limit = self.params.get('ratelimit')
+        if rate_limit is None or byte_counter == 0:
+            return
+        if now is None:
+            now = time.time()
+        elapsed = now - start_time
+        if elapsed <= 0.0:
+            return
+        speed = float(byte_counter) / elapsed
+        if speed > rate_limit:
+            time.sleep(max((byte_counter // rate_limit) - elapsed, 0))
+
+    def temp_name(self, filename):
+        """Returns a temporary filename for the given filename."""
+        if self.params.get('nopart', False) or filename == '-' or \
+                (os.path.exists(encodeFilename(filename)) and not os.path.isfile(encodeFilename(filename))):
+            return filename
+        return filename + '.part'
+
+    def undo_temp_name(self, filename):
+        if filename.endswith('.part'):
+            return filename[:-len('.part')]
+        return filename
+
+    def ytdl_filename(self, filename):
+        return filename + '.ytdl'
+
+    def try_rename(self, old_filename, new_filename):
+        try:
+            if old_filename == new_filename:
+                return
+            os.rename(encodeFilename(old_filename), encodeFilename(new_filename))
+        except (IOError, OSError) as err:
+            self.report_error('unable to rename file: %s' % error_to_compat_str(err))
+
+    def try_utime(self, filename, last_modified_hdr):
+        """Try to set the last-modified time of the given file."""
+        if last_modified_hdr is None:
+            return
+        if not os.path.isfile(encodeFilename(filename)):
+            return
+        timestr = last_modified_hdr
+        if timestr is None:
+            return
+        filetime = timeconvert(timestr)
+        if filetime is None:
+            return filetime
+        # Ignore obviously invalid dates
+        if filetime == 0:
+            return
+        try:
+            os.utime(filename, (time.time(), filetime))
+        except Exception:
+            pass
+        return filetime
+
+    def report_destination(self, filename):
+        """Report destination filename."""
+        self.to_screen('[download] Destination: ' + filename)
+
+    def _report_progress_status(self, msg, is_last_line=False):
+        fullmsg = '[download] ' + msg
+        if self.params.get('progress_with_newline', False):
+            self.to_screen(fullmsg)
+        else:
+            if compat_os_name == 'nt':
+                prev_len = getattr(self, '_report_progress_prev_line_length',
+                                   0)
+                if prev_len > len(fullmsg):
+                    fullmsg += ' ' * (prev_len - len(fullmsg))
+                self._report_progress_prev_line_length = len(fullmsg)
+                clear_line = '\r'
+            else:
+                clear_line = ('\r\x1b[K' if sys.stderr.isatty() else '\r')
+            self.to_screen(clear_line + fullmsg, skip_eol=not is_last_line)
+        self.to_console_title('youtube-dl ' + msg)
+
+    def report_progress(self, s):
+        if s['status'] == 'finished':
+            if self.params.get('noprogress', False):
+                self.to_screen('[download] Download completed')
+            else:
+                msg_template = '100%%'
+                if s.get('total_bytes') is not None:
+                    s['_total_bytes_str'] = format_bytes(s['total_bytes'])
+                    msg_template += ' of %(_total_bytes_str)s'
+                if s.get('elapsed') is not None:
+                    s['_elapsed_str'] = self.format_seconds(s['elapsed'])
+                    msg_template += ' in %(_elapsed_str)s'
+                self._report_progress_status(
+                    msg_template % s, is_last_line=True)
+
+        if self.params.get('noprogress'):
+            return
+
+        if s['status'] != 'downloading':
+            return
+
+        if s.get('eta') is not None:
+            s['_eta_str'] = self.format_eta(s['eta'])
+        else:
+            s['_eta_str'] = 'Unknown ETA'
+
+        if s.get('total_bytes') and s.get('downloaded_bytes') is not None:
+            s['_percent_str'] = self.format_percent(100 * s['downloaded_bytes'] / s['total_bytes'])
+        elif s.get('total_bytes_estimate') and s.get('downloaded_bytes') is not None:
+            s['_percent_str'] = self.format_percent(100 * s['downloaded_bytes'] / s['total_bytes_estimate'])
+        else:
+            if s.get('downloaded_bytes') == 0:
+                s['_percent_str'] = self.format_percent(0)
+            else:
+                s['_percent_str'] = 'Unknown %'
+
+        if s.get('speed') is not None:
+            s['_speed_str'] = self.format_speed(s['speed'])
+        else:
+            s['_speed_str'] = 'Unknown speed'
+
+        if s.get('total_bytes') is not None:
+            s['_total_bytes_str'] = format_bytes(s['total_bytes'])
+            msg_template = '%(_percent_str)s of %(_total_bytes_str)s at %(_speed_str)s ETA %(_eta_str)s'
+        elif s.get('total_bytes_estimate') is not None:
+            s['_total_bytes_estimate_str'] = format_bytes(s['total_bytes_estimate'])
+            msg_template = '%(_percent_str)s of ~%(_total_bytes_estimate_str)s at %(_speed_str)s ETA %(_eta_str)s'
+        else:
+            if s.get('downloaded_bytes') is not None:
+                s['_downloaded_bytes_str'] = format_bytes(s['downloaded_bytes'])
+                if s.get('elapsed'):
+                    s['_elapsed_str'] = self.format_seconds(s['elapsed'])
+                    msg_template = '%(_downloaded_bytes_str)s at %(_speed_str)s (%(_elapsed_str)s)'
+                else:
+                    msg_template = '%(_downloaded_bytes_str)s at %(_speed_str)s'
+            else:
+                msg_template = '%(_percent_str)s % at %(_speed_str)s ETA %(_eta_str)s'
+
+        self._report_progress_status(msg_template % s)
+
+    def report_resuming_byte(self, resume_len):
+        """Report attempt to resume at given byte."""
+        self.to_screen('[download] Resuming download at byte %s' % resume_len)
+
+    def report_retry(self, err, count, retries):
+        """Report retry in case of HTTP error 5xx"""
+        self.to_screen(
+            '[download] Got server HTTP error: %s. Retrying (attempt %d of %s)...'
+            % (error_to_compat_str(err), count, self.format_retries(retries)))
+
+    def report_file_already_downloaded(self, file_name):
+        """Report file has already been fully downloaded."""
+        try:
+            self.to_screen('[download] %s has already been downloaded' % file_name)
+        except UnicodeEncodeError:
+            self.to_screen('[download] The file has already been downloaded')
+
+    def report_unable_to_resume(self):
+        """Report it was impossible to resume download."""
+        self.to_screen('[download] Unable to resume')
+
+    def download(self, filename, info_dict):
+        """Download to a filename using the info from info_dict
+        Return True on success and False otherwise
+        """
+
+        nooverwrites_and_exists = (
+            self.params.get('nooverwrites', False) and
+            os.path.exists(encodeFilename(filename))
+        )
+
+        if not hasattr(filename, 'write'):
+            continuedl_and_exists = (
+                self.params.get('continuedl', True) and
+                os.path.isfile(encodeFilename(filename)) and
+                not self.params.get('nopart', False)
+            )
+
+            # Check file already present
+            if filename != '-' and (nooverwrites_and_exists or continuedl_and_exists):
+                self.report_file_already_downloaded(filename)
+                self._hook_progress({
+                    'filename': filename,
+                    'status': 'finished',
+                    'total_bytes': os.path.getsize(encodeFilename(filename)),
+                })
+                return True
+
+        min_sleep_interval = self.params.get('sleep_interval')
+        if min_sleep_interval:
+            max_sleep_interval = self.params.get('max_sleep_interval', min_sleep_interval)
+            sleep_interval = random.uniform(min_sleep_interval, max_sleep_interval)
+            self.to_screen(
+                '[download] Sleeping %s seconds...' % (
+                    int(sleep_interval) if sleep_interval.is_integer()
+                    else '%.2f' % sleep_interval))
+            time.sleep(sleep_interval)
+
+        return self.real_download(filename, info_dict)
+
+    def real_download(self, filename, info_dict):
+        """Real download process. Redefine in subclasses."""
+        raise NotImplementedError('This method must be implemented by subclasses')
+
+    def _hook_progress(self, status):
+        for ph in self._progress_hooks:
+            ph(status)
+
+    def add_progress_hook(self, ph):
+        # See YoutubeDl.py (search for progress_hooks) for a description of
+        # this interface
+        self._progress_hooks.append(ph)
+
+    def _debug_cmd(self, args, exe=None):
+        if not self.params.get('verbose', False):
+            return
+
+        str_args = [decodeArgument(a) for a in args]
+
+        if exe is None:
+            exe = os.path.basename(str_args[0])
+
+        self.to_screen('[debug] %s command line: %s' % (
+            exe, shell_quote(str_args)))
diff --git a/youtube_dl/downloader/dash.py b/youtube_dl/downloader/dash.py
new file mode 100644
index 0000000..eaa7adf
--- /dev/null
+++ b/youtube_dl/downloader/dash.py
@@ -0,0 +1,80 @@
+from __future__ import unicode_literals
+
+from .fragment import FragmentFD
+from ..compat import compat_urllib_error
+from ..utils import (
+    DownloadError,
+    urljoin,
+)
+
+
+class DashSegmentsFD(FragmentFD):
+    """
+    Download segments in a DASH manifest
+    """
+
+    FD_NAME = 'dashsegments'
+
+    def real_download(self, filename, info_dict):
+        fragment_base_url = info_dict.get('fragment_base_url')
+        fragments = info_dict['fragments'][:1] if self.params.get(
+            'test', False) else info_dict['fragments']
+
+        ctx = {
+            'filename': filename,
+            'total_frags': len(fragments),
+        }
+
+        self._prepare_and_start_frag_download(ctx)
+
+        fragment_retries = self.params.get('fragment_retries', 0)
+        skip_unavailable_fragments = self.params.get('skip_unavailable_fragments', True)
+
+        frag_index = 0
+        for i, fragment in enumerate(fragments):
+            frag_index += 1
+            if frag_index <= ctx['fragment_index']:
+                continue
+            # In DASH, the first segment contains necessary headers to
+            # generate a valid MP4 file, so always abort for the first segment
+            fatal = i == 0 or not skip_unavailable_fragments
+            count = 0
+            while count <= fragment_retries:
+                try:
+                    fragment_url = fragment.get('url')
+                    if not fragment_url:
+                        assert fragment_base_url
+                        fragment_url = urljoin(fragment_base_url, fragment['path'])
+                    success, frag_content = self._download_fragment(ctx, fragment_url, info_dict)
+                    if not success:
+                        return False
+                    self._append_fragment(ctx, frag_content)
+                    break
+                except compat_urllib_error.HTTPError as err:
+                    # YouTube may often return 404 HTTP error for a fragment causing the
+                    # whole download to fail. However if the same fragment is immediately
+                    # retried with the same request data this usually succeeds (1-2 attemps
+                    # is usually enough) thus allowing to download the whole file successfully.
+                    # To be future-proof we will retry all fragments that fail with any
+                    # HTTP error.
+                    count += 1
+                    if count <= fragment_retries:
+                        self.report_retry_fragment(err, frag_index, count, fragment_retries)
+                except DownloadError:
+                    # Don't retry fragment if error occurred during HTTP downloading
+                    # itself since it has own retry settings
+                    if not fatal:
+                        self.report_skip_fragment(frag_index)
+                        break
+                    raise
+
+            if count > fragment_retries:
+                if not fatal:
+                    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)
+
+        return True
diff --git a/youtube_dl/downloader/external.py b/youtube_dl/downloader/external.py
new file mode 100644
index 0000000..958d00a
--- /dev/null
+++ b/youtube_dl/downloader/external.py
@@ -0,0 +1,354 @@
+from __future__ import unicode_literals
+
+import os.path
+import re
+import subprocess
+import sys
+import time
+
+from .common import FileDownloader
+from ..compat import (
+    compat_setenv,
+    compat_str,
+)
+from ..postprocessor.ffmpeg import FFmpegPostProcessor, EXT_TO_OUT_FORMATS
+from ..utils import (
+    cli_option,
+    cli_valueless_option,
+    cli_bool_option,
+    cli_configuration_args,
+    encodeFilename,
+    encodeArgument,
+    handle_youtubedl_headers,
+    check_executable,
+    is_outdated_version,
+)
+
+
+class ExternalFD(FileDownloader):
+    def real_download(self, filename, info_dict):
+        self.report_destination(filename)
+        tmpfilename = self.temp_name(filename)
+
+        try:
+            started = time.time()
+            retval = self._call_downloader(tmpfilename, info_dict)
+        except KeyboardInterrupt:
+            if not info_dict.get('is_live'):
+                raise
+            # Live stream downloading cancellation should be considered as
+            # correct and expected termination thus all postprocessing
+            # should take place
+            retval = 0
+            self.to_screen('[%s] Interrupted by user' % self.get_basename())
+
+        if retval == 0:
+            status = {
+                'filename': filename,
+                'status': 'finished',
+                'elapsed': time.time() - started,
+            }
+            if filename != '-':
+                fsize = os.path.getsize(encodeFilename(tmpfilename))
+                self.to_screen('\r[%s] Downloaded %s bytes' % (self.get_basename(), fsize))
+                self.try_rename(tmpfilename, filename)
+                status.update({
+                    'downloaded_bytes': fsize,
+                    'total_bytes': fsize,
+                })
+            self._hook_progress(status)
+            return True
+        else:
+            self.to_stderr('\n')
+            self.report_error('%s exited with code %d' % (
+                self.get_basename(), retval))
+            return False
+
+    @classmethod
+    def get_basename(cls):
+        return cls.__name__[:-2].lower()
+
+    @property
+    def exe(self):
+        return self.params.get('external_downloader')
+
+    @classmethod
+    def available(cls):
+        return check_executable(cls.get_basename(), [cls.AVAILABLE_OPT])
+
+    @classmethod
+    def supports(cls, info_dict):
+        return info_dict['protocol'] in ('http', 'https', 'ftp', 'ftps')
+
+    @classmethod
+    def can_download(cls, info_dict):
+        return cls.available() and cls.supports(info_dict)
+
+    def _option(self, command_option, param):
+        return cli_option(self.params, command_option, param)
+
+    def _bool_option(self, command_option, param, true_value='true', false_value='false', separator=None):
+        return cli_bool_option(self.params, command_option, param, true_value, false_value, separator)
+
+    def _valueless_option(self, command_option, param, expected_value=True):
+        return cli_valueless_option(self.params, command_option, param, expected_value)
+
+    def _configuration_args(self, default=[]):
+        return cli_configuration_args(self.params, 'external_downloader_args', default)
+
+    def _call_downloader(self, tmpfilename, info_dict):
+        """ Either overwrite this or implement _make_cmd """
+        cmd = [encodeArgument(a) for a in self._make_cmd(tmpfilename, info_dict)]
+
+        self._debug_cmd(cmd)
+
+        p = subprocess.Popen(
+            cmd, stderr=subprocess.PIPE)
+        _, stderr = p.communicate()
+        if p.returncode != 0:
+            self.to_stderr(stderr.decode('utf-8', 'replace'))
+        return p.returncode
+
+
+class CurlFD(ExternalFD):
+    AVAILABLE_OPT = '-V'
+
+    def _make_cmd(self, tmpfilename, info_dict):
+        cmd = [self.exe, '--location', '-o', tmpfilename]
+        for key, val in info_dict['http_headers'].items():
+            cmd += ['--header', '%s: %s' % (key, val)]
+        cmd += self._bool_option('--continue-at', 'continuedl', '-', '0')
+        cmd += self._valueless_option('--silent', 'noprogress')
+        cmd += self._valueless_option('--verbose', 'verbose')
+        cmd += self._option('--limit-rate', 'ratelimit')
+        cmd += self._option('--retry', 'retries')
+        cmd += self._option('--max-filesize', 'max_filesize')
+        cmd += self._option('--interface', 'source_address')
+        cmd += self._option('--proxy', 'proxy')
+        cmd += self._valueless_option('--insecure', 'nocheckcertificate')
+        cmd += self._configuration_args()
+        cmd += ['--', info_dict['url']]
+        return cmd
+
+    def _call_downloader(self, tmpfilename, info_dict):
+        cmd = [encodeArgument(a) for a in self._make_cmd(tmpfilename, info_dict)]
+
+        self._debug_cmd(cmd)
+
+        # curl writes the progress to stderr so don't capture it.
+        p = subprocess.Popen(cmd)
+        p.communicate()
+        return p.returncode
+
+
+class AxelFD(ExternalFD):
+    AVAILABLE_OPT = '-V'
+
+    def _make_cmd(self, tmpfilename, info_dict):
+        cmd = [self.exe, '-o', tmpfilename]
+        for key, val in info_dict['http_headers'].items():
+            cmd += ['-H', '%s: %s' % (key, val)]
+        cmd += self._configuration_args()
+        cmd += ['--', info_dict['url']]
+        return cmd
+
+
+class WgetFD(ExternalFD):
+    AVAILABLE_OPT = '--version'
+
+    def _make_cmd(self, tmpfilename, info_dict):
+        cmd = [self.exe, '-O', tmpfilename, '-nv', '--no-cookies']
+        for key, val in info_dict['http_headers'].items():
+            cmd += ['--header', '%s: %s' % (key, val)]
+        cmd += self._option('--bind-address', 'source_address')
+        cmd += self._option('--proxy', 'proxy')
+        cmd += self._valueless_option('--no-check-certificate', 'nocheckcertificate')
+        cmd += self._configuration_args()
+        cmd += ['--', info_dict['url']]
+        return cmd
+
+
+class Aria2cFD(ExternalFD):
+    AVAILABLE_OPT = '-v'
+
+    def _make_cmd(self, tmpfilename, info_dict):
+        cmd = [self.exe, '-c']
+        cmd += self._configuration_args([
+            '--min-split-size', '1M', '--max-connection-per-server', '4'])
+        dn = os.path.dirname(tmpfilename)
+        if dn:
+            cmd += ['--dir', dn]
+        cmd += ['--out', os.path.basename(tmpfilename)]
+        for key, val in info_dict['http_headers'].items():
+            cmd += ['--header', '%s: %s' % (key, val)]
+        cmd += self._option('--interface', 'source_address')
+        cmd += self._option('--all-proxy', 'proxy')
+        cmd += self._bool_option('--check-certificate', 'nocheckcertificate', 'false', 'true', '=')
+        cmd += ['--', info_dict['url']]
+        return cmd
+
+
+class HttpieFD(ExternalFD):
+    @classmethod
+    def available(cls):
+        return check_executable('http', ['--version'])
+
+    def _make_cmd(self, tmpfilename, info_dict):
+        cmd = ['http', '--download', '--output', tmpfilename, info_dict['url']]
+        for key, val in info_dict['http_headers'].items():
+            cmd += ['%s:%s' % (key, val)]
+        return cmd
+
+
+class FFmpegFD(ExternalFD):
+    @classmethod
+    def supports(cls, info_dict):
+        return info_dict['protocol'] in ('http', 'https', 'ftp', 'ftps', 'm3u8', 'rtsp', 'rtmp', 'mms')
+
+    @classmethod
+    def available(cls):
+        return FFmpegPostProcessor().available
+
+    def _call_downloader(self, tmpfilename, info_dict):
+        url = info_dict['url']
+        ffpp = FFmpegPostProcessor(downloader=self)
+        if not ffpp.available:
+            self.report_error('m3u8 download detected but ffmpeg or avconv could not be found. Please install one.')
+            return False
+        ffpp.check_version()
+
+        args = [ffpp.executable, '-y']
+
+        for log_level in ('quiet', 'verbose'):
+            if self.params.get(log_level, False):
+                args += ['-loglevel', log_level]
+                break
+
+        seekable = info_dict.get('_seekable')
+        if seekable is not None:
+            # setting -seekable prevents ffmpeg from guessing if the server
+            # supports seeking(by adding the header `Range: bytes=0-`), which
+            # can cause problems in some cases
+            # https://github.com/rg3/youtube-dl/issues/11800#issuecomment-275037127
+            # http://trac.ffmpeg.org/ticket/6125#comment:10
+            args += ['-seekable', '1' if seekable else '0']
+
+        args += self._configuration_args()
+
+        # start_time = info_dict.get('start_time') or 0
+        # if start_time:
+        #     args += ['-ss', compat_str(start_time)]
+        # end_time = info_dict.get('end_time')
+        # if end_time:
+        #     args += ['-t', compat_str(end_time - start_time)]
+
+        if info_dict['http_headers'] and re.match(r'^https?://', url):
+            # Trailing \r\n after each HTTP header is important to prevent warning from ffmpeg/avconv:
+            # [http @ 00000000003d2fa0] No trailing CRLF found in HTTP header.
+            headers = handle_youtubedl_headers(info_dict['http_headers'])
+            args += [
+                '-headers',
+                ''.join('%s: %s\r\n' % (key, val) for key, val in headers.items())]
+
+        env = None
+        proxy = self.params.get('proxy')
+        if proxy:
+            if not re.match(r'^[\da-zA-Z]+://', proxy):
+                proxy = 'http://%s' % proxy
+
+            if proxy.startswith('socks'):
+                self.report_warning(
+                    '%s does not support SOCKS proxies. Downloading is likely to fail. '
+                    'Consider adding --hls-prefer-native to your command.' % self.get_basename())
+
+            # Since December 2015 ffmpeg supports -http_proxy option (see
+            # http://git.videolan.org/?p=ffmpeg.git;a=commit;h=b4eb1f29ebddd60c41a2eb39f5af701e38e0d3fd)
+            # We could switch to the following code if we are able to detect version properly
+            # args += ['-http_proxy', proxy]
+            env = os.environ.copy()
+            compat_setenv('HTTP_PROXY', proxy, env=env)
+            compat_setenv('http_proxy', proxy, env=env)
+
+        protocol = info_dict.get('protocol')
+
+        if protocol == 'rtmp':
+            player_url = info_dict.get('player_url')
+            page_url = info_dict.get('page_url')
+            app = info_dict.get('app')
+            play_path = info_dict.get('play_path')
+            tc_url = info_dict.get('tc_url')
+            flash_version = info_dict.get('flash_version')
+            live = info_dict.get('rtmp_live', False)
+            if player_url is not None:
+                args += ['-rtmp_swfverify', player_url]
+            if page_url is not None:
+                args += ['-rtmp_pageurl', page_url]
+            if app is not None:
+                args += ['-rtmp_app', app]
+            if play_path is not None:
+                args += ['-rtmp_playpath', play_path]
+            if tc_url is not None:
+                args += ['-rtmp_tcurl', tc_url]
+            if flash_version is not None:
+                args += ['-rtmp_flashver', flash_version]
+            if live:
+                args += ['-rtmp_live', 'live']
+
+        args += ['-i', url, '-c', 'copy']
+
+        if self.params.get('test', False):
+            args += ['-fs', compat_str(self._TEST_FILE_SIZE)]
+
+        if protocol in ('m3u8', 'm3u8_native'):
+            if self.params.get('hls_use_mpegts', False) or tmpfilename == '-':
+                args += ['-f', 'mpegts']
+            else:
+                args += ['-f', 'mp4']
+                if (ffpp.basename == 'ffmpeg' and is_outdated_version(ffpp._versions['ffmpeg'], '3.2', False)) and (not info_dict.get('acodec') or info_dict['acodec'].split('.')[0] in ('aac', 'mp4a')):
+                    args += ['-bsf:a', 'aac_adtstoasc']
+        elif protocol == 'rtmp':
+            args += ['-f', 'flv']
+        else:
+            args += ['-f', EXT_TO_OUT_FORMATS.get(info_dict['ext'], info_dict['ext'])]
+
+        args = [encodeArgument(opt) for opt in args]
+        args.append(encodeFilename(ffpp._ffmpeg_filename_argument(tmpfilename), True))
+
+        self._debug_cmd(args)
+
+        proc = subprocess.Popen(args, stdin=subprocess.PIPE, env=env)
+        try:
+            retval = proc.wait()
+        except KeyboardInterrupt:
+            # subprocces.run would send the SIGKILL signal to ffmpeg and the
+            # mp4 file couldn't be played, but if we ask ffmpeg to quit it
+            # produces a file that is playable (this is mostly useful for live
+            # streams). Note that Windows is not affected and produces playable
+            # files (see https://github.com/rg3/youtube-dl/issues/8300).
+            if sys.platform != 'win32':
+                proc.communicate(b'q')
+            raise
+        return retval
+
+
+class AVconvFD(FFmpegFD):
+    pass
+
+
+_BY_NAME = dict(
+    (klass.get_basename(), klass)
+    for name, klass in globals().items()
+    if name.endswith('FD') and name != 'ExternalFD'
+)
+
+
+def list_external_downloaders():
+    return sorted(_BY_NAME.keys())
+
+
+def get_external_downloader(external_downloader):
+    """ Given the name of the executable, see whether we support the given
+        downloader . """
+    # Drop .exe extension on Windows
+    bn = os.path.splitext(os.path.basename(external_downloader))[0]
+    return _BY_NAME[bn]
diff --git a/youtube_dl/downloader/f4m.py b/youtube_dl/downloader/f4m.py
new file mode 100644
index 0000000..15e71be
--- /dev/null
+++ b/youtube_dl/downloader/f4m.py
@@ -0,0 +1,438 @@
+from __future__ import division, unicode_literals
+
+import io
+import itertools
+import time
+
+from .fragment import FragmentFD
+from ..compat import (
+    compat_b64decode,
+    compat_etree_fromstring,
+    compat_urlparse,
+    compat_urllib_error,
+    compat_urllib_parse_urlparse,
+    compat_struct_pack,
+    compat_struct_unpack,
+)
+from ..utils import (
+    fix_xml_ampersands,
+    xpath_text,
+)
+
+
+class DataTruncatedError(Exception):
+    pass
+
+
+class FlvReader(io.BytesIO):
+    """
+    Reader for Flv files
+    The file format is documented in https://www.adobe.com/devnet/f4v.html
+    """
+
+    def read_bytes(self, n):
+        data = self.read(n)
+        if len(data) < n:
+            raise DataTruncatedError(
+                'FlvReader error: need %d bytes while only %d bytes got' % (
+                    n, len(data)))
+        return data
+
+    # Utility functions for reading numbers and strings
+    def read_unsigned_long_long(self):
+        return compat_struct_unpack('!Q', self.read_bytes(8))[0]
+
+    def read_unsigned_int(self):
+        return compat_struct_unpack('!I', self.read_bytes(4))[0]
+
+    def read_unsigned_char(self):
+        return compat_struct_unpack('!B', self.read_bytes(1))[0]
+
+    def read_string(self):
+        res = b''
+        while True:
+            char = self.read_bytes(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_bytes(4)
+        header_end = 8
+        if size == 1:
+            real_size = self.read_unsigned_long_long()
+            header_end = 16
+        return real_size, box_type, self.read_bytes(real_size - header_end)
+
+    def read_asrt(self):
+        # version
+        self.read_unsigned_char()
+        # flags
+        self.read_bytes(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_bytes(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_bytes(3)
+
+        self.read_unsigned_int()  # BootstrapinfoVersion
+        # Profile,Live,Update,Reserved
+        flags = self.read_unsigned_char()
+        live = flags & 0x20 != 0
+        # 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,
+            'live': live,
+        }
+
+    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']:
+        # In some live HDS streams (for example Rai), `fragments_count` is
+        # abnormal and causing out-of-memory errors. It's OK to change the
+        # number of fragments for live streams as they are updated periodically
+        if fragments_count == 4294967295 and boot_info['live']:
+            fragments_count = 2
+        for _ in range(fragments_count):
+            res.append((segment, next(fragments_counter)))
+
+    if boot_info['live']:
+        res = res[-2:]
+
+    return res
+
+
+def write_unsigned_int(stream, val):
+    stream.write(compat_struct_pack('!I', val))
+
+
+def write_unsigned_int_24(stream, val):
+    stream.write(compat_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 remove_encrypted_media(media):
+    return list(filter(lambda e: 'drmAdditionalHeaderId' not in e.attrib and
+                                 'drmAdditionalHeaderSetId' not in e.attrib,
+                       media))
+
+
+def _add_ns(prop, ver=1):
+    return '{http://ns.adobe.com/f4m/%d.0}%s' % (ver, prop)
+
+
+def get_base_url(manifest):
+    base_url = xpath_text(
+        manifest, [_add_ns('baseURL'), _add_ns('baseURL', 2)],
+        'base URL', default=None)
+    if base_url:
+        base_url = base_url.strip()
+    return base_url
+
+
+class F4mFD(FragmentFD):
+    """
+    A downloader for f4m manifests or AdobeHDS.
+    """
+
+    FD_NAME = 'f4m'
+
+    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 = remove_encrypted_media(media)
+        if not media:
+            self.report_error('Unsupported DRM')
+        return media
+
+    def _get_bootstrap_from_url(self, bootstrap_url):
+        bootstrap = self.ydl.urlopen(bootstrap_url).read()
+        return read_bootstrap_info(bootstrap)
+
+    def _update_live_fragments(self, bootstrap_url, latest_fragment):
+        fragments_list = []
+        retries = 30
+        while (not fragments_list) and (retries > 0):
+            boot_info = self._get_bootstrap_from_url(bootstrap_url)
+            fragments_list = build_fragments_list(boot_info)
+            fragments_list = [f for f in fragments_list if f[1] > latest_fragment]
+            if not fragments_list:
+                # Retry after a while
+                time.sleep(5.0)
+                retries -= 1
+
+        if not fragments_list:
+            self.report_error('Failed to update fragments')
+
+        return fragments_list
+
+    def _parse_bootstrap_node(self, node, base_url):
+        # Sometimes non empty inline bootstrap info can be specified along
+        # with bootstrap url attribute (e.g. dummy inline bootstrap info
+        # contains whitespace characters in [1]). We will prefer bootstrap
+        # url over inline bootstrap info when present.
+        # 1. http://live-1-1.rutube.ru/stream/1024/HDS/SD/C2NKsS85HQNckgn5HdEmOQ/1454167650/S-s604419906/move/four/dirs/upper/1024-576p.f4m
+        bootstrap_url = node.get('url')
+        if bootstrap_url:
+            bootstrap_url = compat_urlparse.urljoin(
+                base_url, bootstrap_url)
+            boot_info = self._get_bootstrap_from_url(bootstrap_url)
+        else:
+            bootstrap_url = None
+            bootstrap = compat_b64decode(node.text)
+            boot_info = read_bootstrap_info(bootstrap)
+        return boot_info, bootstrap_url
+
+    def real_download(self, filename, info_dict):
+        man_url = info_dict['url']
+        requested_bitrate = info_dict.get('tbr')
+        self.to_screen('[%s] Downloading f4m manifest' % self.FD_NAME)
+
+        urlh = self.ydl.urlopen(self._prepare_url(info_dict, man_url))
+        man_url = urlh.geturl()
+        # Some manifests may be malformed, e.g. prosiebensat1 generated manifests
+        # (see https://github.com/rg3/youtube-dl/issues/6215#issuecomment-121704244
+        # and https://github.com/rg3/youtube-dl/issues/7823)
+        manifest = fix_xml_ampersands(urlh.read().decode('utf-8', 'ignore')).strip()
+
+        doc = compat_etree_fromstring(manifest)
+        formats = [(int(f.attrib.get('bitrate', -1)), f)
+                   for f in self._get_unencrypted_media(doc)]
+        if requested_bitrate is None or len(formats) == 1:
+            # 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]
+
+        # Prefer baseURL for relative URLs as per 11.2 of F4M 3.0 spec.
+        man_base_url = get_base_url(doc) or man_url
+
+        base_url = compat_urlparse.urljoin(man_base_url, media.attrib['url'])
+        bootstrap_node = doc.find(_add_ns('bootstrapInfo'))
+        boot_info, bootstrap_url = self._parse_bootstrap_node(
+            bootstrap_node, man_base_url)
+        live = boot_info['live']
+        metadata_node = media.find(_add_ns('metadata'))
+        if metadata_node is not None:
+            metadata = compat_b64decode(metadata_node.text)
+        else:
+            metadata = None
+
+        fragments_list = build_fragments_list(boot_info)
+        test = self.params.get('test', False)
+        if test:
+            # 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'))
+
+        ctx = {
+            'filename': filename,
+            'total_frags': total_frags,
+            'live': live,
+        }
+
+        self._prepare_frag_download(ctx)
+
+        dest_stream = ctx['dest_stream']
+
+        if ctx['complete_frags_downloaded_bytes'] == 0:
+            write_flv_header(dest_stream)
+            if not live:
+                write_metadata_tag(dest_stream, metadata)
+
+        base_url_parsed = compat_urllib_parse_urlparse(base_url)
+
+        self._start_frag_download(ctx)
+
+        frag_index = 0
+        while fragments_list:
+            seg_i, frag_i = fragments_list.pop(0)
+            frag_index += 1
+            if frag_index <= ctx['fragment_index']:
+                continue
+            name = 'Seg%d-Frag%d' % (seg_i, frag_i)
+            query = []
+            if base_url_parsed.query:
+                query.append(base_url_parsed.query)
+            if akamai_pv:
+                query.append(akamai_pv.strip(';'))
+            if info_dict.get('extra_param_to_segment_url'):
+                query.append(info_dict['extra_param_to_segment_url'])
+            url_parsed = base_url_parsed._replace(path=base_url_parsed.path + name, query='&'.join(query))
+            try:
+                success, down_data = self._download_fragment(ctx, url_parsed.geturl(), info_dict)
+                if not success:
+                    return False
+                reader = FlvReader(down_data)
+                while True:
+                    try:
+                        _, box_type, box_data = reader.read_box_info()
+                    except DataTruncatedError:
+                        if test:
+                            # In tests, segments may be truncated, and thus
+                            # FlvReader may not be able to parse the whole
+                            # chunk. If so, write the segment as is
+                            # See https://github.com/rg3/youtube-dl/issues/9214
+                            dest_stream.write(down_data)
+                            break
+                        raise
+                    if box_type == b'mdat':
+                        self._append_fragment(ctx, box_data)
+                        break
+            except (compat_urllib_error.HTTPError, ) as err:
+                if live and (err.code == 404 or err.code == 410):
+                    # We didn't keep up with the live window. Continue
+                    # with the next available fragment.
+                    msg = 'Fragment %d unavailable' % frag_i
+                    self.report_warning(msg)
+                    fragments_list = []
+                else:
+                    raise
+
+            if not fragments_list and not test and live and bootstrap_url:
+                fragments_list = self._update_live_fragments(bootstrap_url, frag_i)
+                total_frags += len(fragments_list)
+                if fragments_list and (fragments_list[0][1] > frag_i + 1):
+                    msg = 'Missed %d fragments' % (fragments_list[0][1] - (frag_i + 1))
+                    self.report_warning(msg)
+
+        self._finish_frag_download(ctx)
+
+        return True
diff --git a/youtube_dl/downloader/fragment.py b/youtube_dl/downloader/fragment.py
new file mode 100644
index 0000000..917f6dc
--- /dev/null
+++ b/youtube_dl/downloader/fragment.py
@@ -0,0 +1,268 @@
+from __future__ import division, unicode_literals
+
+import os
+import time
+import json
+
+from .common import FileDownloader
+from .http import HttpFD
+from ..utils import (
+    error_to_compat_str,
+    encodeFilename,
+    sanitize_open,
+    sanitized_Request,
+)
+
+
+class HttpQuietDownloader(HttpFD):
+    def to_screen(self, *args, **kargs):
+        pass
+
+
+class FragmentFD(FileDownloader):
+    """
+    A base file downloader class for fragmented media (e.g. f4m/m3u8 manifests).
+
+    Available options:
+
+    fragment_retries:   Number of times to retry a fragment for HTTP error (DASH
+                        and hlsnative only)
+    skip_unavailable_fragments:
+                        Skip unavailable fragments (DASH and hlsnative only)
+    keep_fragments:     Keep downloaded fragments on disk after downloading is
+                        finished
+
+    For each incomplete fragment download youtube-dl keeps on disk a special
+    bookkeeping file with download state and metadata (in future such files will
+    be used for any incomplete download handled by youtube-dl). This file is
+    used to properly handle resuming, check download file consistency and detect
+    potential errors. The file has a .ytdl extension and represents a standard
+    JSON file of the following format:
+
+    extractor:
+        Dictionary of extractor related data. TBD.
+
+    downloader:
+        Dictionary of downloader related data. May contain following data:
+            current_fragment:
+                Dictionary with current (being downloaded) fragment data:
+                index:  0-based index of current fragment among all fragments
+            fragment_count:
+                Total count of fragments
+
+    This feature is experimental and file format may change in future.
+    """
+
+    def report_retry_fragment(self, err, frag_index, count, retries):
+        self.to_screen(
+            '[download] Got server HTTP error: %s. Retrying fragment %d (attempt %d of %s)...'
+            % (error_to_compat_str(err), frag_index, count, self.format_retries(retries)))
+
+    def report_skip_fragment(self, frag_index):
+        self.to_screen('[download] Skipping fragment %d...' % frag_index)
+
+    def _prepare_url(self, info_dict, url):
+        headers = info_dict.get('http_headers')
+        return sanitized_Request(url, None, headers) if headers else url
+
+    def _prepare_and_start_frag_download(self, ctx):
+        self._prepare_frag_download(ctx)
+        self._start_frag_download(ctx)
+
+    @staticmethod
+    def __do_ytdl_file(ctx):
+        return not ctx['live'] and not ctx['tmpfilename'] == '-'
+
+    def _read_ytdl_file(self, ctx):
+        assert 'ytdl_corrupt' not in ctx
+        stream, _ = sanitize_open(self.ytdl_filename(ctx['filename']), 'r')
+        try:
+            ctx['fragment_index'] = json.loads(stream.read())['downloader']['current_fragment']['index']
+        except Exception:
+            ctx['ytdl_corrupt'] = True
+        finally:
+            stream.close()
+
+    def _write_ytdl_file(self, ctx):
+        frag_index_stream, _ = sanitize_open(self.ytdl_filename(ctx['filename']), 'w')
+        downloader = {
+            'current_fragment': {
+                'index': ctx['fragment_index'],
+            },
+        }
+        if ctx.get('fragment_count') is not None:
+            downloader['fragment_count'] = ctx['fragment_count']
+        frag_index_stream.write(json.dumps({'downloader': downloader}))
+        frag_index_stream.close()
+
+    def _download_fragment(self, ctx, frag_url, info_dict, headers=None):
+        fragment_filename = '%s-Frag%d' % (ctx['tmpfilename'], ctx['fragment_index'])
+        success = ctx['dl'].download(fragment_filename, {
+            'url': frag_url,
+            'http_headers': headers or info_dict.get('http_headers'),
+        })
+        if not success:
+            return False, None
+        down, frag_sanitized = sanitize_open(fragment_filename, 'rb')
+        ctx['fragment_filename_sanitized'] = frag_sanitized
+        frag_content = down.read()
+        down.close()
+        return True, frag_content
+
+    def _append_fragment(self, ctx, frag_content):
+        try:
+            ctx['dest_stream'].write(frag_content)
+            ctx['dest_stream'].flush()
+        finally:
+            if self.__do_ytdl_file(ctx):
+                self._write_ytdl_file(ctx)
+            if not self.params.get('keep_fragments', False):
+                os.remove(encodeFilename(ctx['fragment_filename_sanitized']))
+            del ctx['fragment_filename_sanitized']
+
+    def _prepare_frag_download(self, ctx):
+        if 'live' not in ctx:
+            ctx['live'] = False
+        if not ctx['live']:
+            total_frags_str = '%d' % ctx['total_frags']
+            ad_frags = ctx.get('ad_frags', 0)
+            if ad_frags:
+                total_frags_str += ' (not including %d ad)' % ad_frags
+        else:
+            total_frags_str = 'unknown (live)'
+        self.to_screen(
+            '[%s] Total fragments: %s' % (self.FD_NAME, total_frags_str))
+        self.report_destination(ctx['filename'])
+        dl = HttpQuietDownloader(
+            self.ydl,
+            {
+                'continuedl': True,
+                'quiet': True,
+                'noprogress': True,
+                'ratelimit': self.params.get('ratelimit'),
+                'retries': self.params.get('retries', 0),
+                'nopart': self.params.get('nopart', False),
+                'test': self.params.get('test', False),
+            }
+        )
+        tmpfilename = self.temp_name(ctx['filename'])
+        open_mode = 'wb'
+        resume_len = 0
+
+        # Establish possible resume length
+        if os.path.isfile(encodeFilename(tmpfilename)):
+            open_mode = 'ab'
+            resume_len = os.path.getsize(encodeFilename(tmpfilename))
+
+        # Should be initialized before ytdl file check
+        ctx.update({
+            'tmpfilename': tmpfilename,
+            'fragment_index': 0,
+        })
+
+        if self.__do_ytdl_file(ctx):
+            if os.path.isfile(encodeFilename(self.ytdl_filename(ctx['filename']))):
+                self._read_ytdl_file(ctx)
+                is_corrupt = ctx.get('ytdl_corrupt') is True
+                is_inconsistent = ctx['fragment_index'] > 0 and resume_len == 0
+                if is_corrupt or is_inconsistent:
+                    message = (
+                        '.ytdl file is corrupt' if is_corrupt else
+                        'Inconsistent state of incomplete fragment download')
+                    self.report_warning(
+                        '%s. Restarting from the beginning...' % message)
+                    ctx['fragment_index'] = resume_len = 0
+                    if 'ytdl_corrupt' in ctx:
+                        del ctx['ytdl_corrupt']
+                    self._write_ytdl_file(ctx)
+            else:
+                self._write_ytdl_file(ctx)
+                assert ctx['fragment_index'] == 0
+
+        dest_stream, tmpfilename = sanitize_open(tmpfilename, open_mode)
+
+        ctx.update({
+            'dl': dl,
+            'dest_stream': dest_stream,
+            'tmpfilename': tmpfilename,
+            # Total complete fragments downloaded so far in bytes
+            'complete_frags_downloaded_bytes': resume_len,
+        })
+
+    def _start_frag_download(self, ctx):
+        total_frags = ctx['total_frags']
+        # This dict stores the download progress, it's updated by the progress
+        # hook
+        state = {
+            'status': 'downloading',
+            'downloaded_bytes': ctx['complete_frags_downloaded_bytes'],
+            'fragment_index': ctx['fragment_index'],
+            'fragment_count': total_frags,
+            'filename': ctx['filename'],
+            'tmpfilename': ctx['tmpfilename'],
+        }
+
+        start = time.time()
+        ctx.update({
+            'started': start,
+            # Amount of fragment's bytes downloaded by the time of the previous
+            # frag progress hook invocation
+            'prev_frag_downloaded_bytes': 0,
+        })
+
+        def frag_progress_hook(s):
+            if s['status'] not in ('downloading', 'finished'):
+                return
+
+            time_now = time.time()
+            state['elapsed'] = time_now - start
+            frag_total_bytes = s.get('total_bytes') or 0
+            if not ctx['live']:
+                estimated_size = (
+                    (ctx['complete_frags_downloaded_bytes'] + frag_total_bytes) /
+                    (state['fragment_index'] + 1) * total_frags)
+                state['total_bytes_estimate'] = estimated_size
+
+            if s['status'] == 'finished':
+                state['fragment_index'] += 1
+                ctx['fragment_index'] = state['fragment_index']
+                state['downloaded_bytes'] += frag_total_bytes - ctx['prev_frag_downloaded_bytes']
+                ctx['complete_frags_downloaded_bytes'] = state['downloaded_bytes']
+                ctx['prev_frag_downloaded_bytes'] = 0
+            else:
+                frag_downloaded_bytes = s['downloaded_bytes']
+                state['downloaded_bytes'] += frag_downloaded_bytes - ctx['prev_frag_downloaded_bytes']
+                if not ctx['live']:
+                    state['eta'] = self.calc_eta(
+                        start, time_now, estimated_size,
+                        state['downloaded_bytes'])
+                state['speed'] = s.get('speed') or ctx.get('speed')
+                ctx['speed'] = state['speed']
+                ctx['prev_frag_downloaded_bytes'] = frag_downloaded_bytes
+            self._hook_progress(state)
+
+        ctx['dl'].add_progress_hook(frag_progress_hook)
+
+        return start
+
+    def _finish_frag_download(self, ctx):
+        ctx['dest_stream'].close()
+        if self.__do_ytdl_file(ctx):
+            ytdl_filename = encodeFilename(self.ytdl_filename(ctx['filename']))
+            if os.path.isfile(ytdl_filename):
+                os.remove(ytdl_filename)
+        elapsed = time.time() - ctx['started']
+
+        if ctx['tmpfilename'] == '-':
+            downloaded_bytes = ctx['complete_frags_downloaded_bytes']
+        else:
+            self.try_rename(ctx['tmpfilename'], ctx['filename'])
+            downloaded_bytes = os.path.getsize(encodeFilename(ctx['filename']))
+
+        self._hook_progress({
+            'downloaded_bytes': downloaded_bytes,
+            'total_bytes': downloaded_bytes,
+            'filename': ctx['filename'],
+            'status': 'finished',
+            'elapsed': elapsed,
+        })
diff --git a/youtube_dl/downloader/hls.py b/youtube_dl/downloader/hls.py
new file mode 100644
index 0000000..fd30452
--- /dev/null
+++ b/youtube_dl/downloader/hls.py
@@ -0,0 +1,204 @@
+from __future__ import unicode_literals
+
+import re
+import binascii
+try:
+    from Crypto.Cipher import AES
+    can_decrypt_frag = True
+except ImportError:
+    can_decrypt_frag = False
+
+from .fragment import FragmentFD
+from .external import FFmpegFD
+
+from ..compat import (
+    compat_urllib_error,
+    compat_urlparse,
+    compat_struct_pack,
+)
+from ..utils import (
+    parse_m3u8_attributes,
+    update_url_query,
+)
+
+
+class HlsFD(FragmentFD):
+    """ A limited implementation that does not require ffmpeg """
+
+    FD_NAME = 'hlsnative'
+
+    @staticmethod
+    def can_download(manifest, info_dict):
+        UNSUPPORTED_FEATURES = (
+            r'#EXT-X-KEY:METHOD=(?!NONE|AES-128)',  # encrypted streams [1]
+            # 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]
+
+            # 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
+        )
+        check_results = [not re.search(feature, manifest) for feature in UNSUPPORTED_FEATURES]
+        is_aes128_enc = '#EXT-X-KEY:METHOD=AES-128' in manifest
+        check_results.append(can_decrypt_frag or not is_aes128_enc)
+        check_results.append(not (is_aes128_enc and r'#EXT-X-BYTERANGE' in manifest))
+        check_results.append(not info_dict.get('is_live'))
+        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):
+            if info_dict.get('extra_param_to_segment_url'):
+                self.report_error('pycrypto not found. Please install it.')
+                return False
+            self.report_warning(
+                'hlsnative has detected features it does not support, '
+                'extraction will be delegated to ffmpeg')
+            fd = FFmpegFD(self.ydl, self.params)
+            for ph in self._progress_hooks:
+                fd.add_progress_hook(ph)
+            return fd.real_download(filename, info_dict)
+
+        def is_ad_fragment(s):
+            return (s.startswith('#ANVATO-SEGMENT-INFO') and 'type=ad' in s or
+                    s.startswith('#UPLYNK-SEGMENT') and s.endswith(',ad'))
+
+        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(line):
+                    ad_frags += 1
+                    ad_frag_next = True
+                continue
+            if ad_frag_next:
+                ad_frag_next = False
+                continue
+            media_frags += 1
+
+        ctx = {
+            'filename': filename,
+            'total_frags': media_frags,
+            'ad_frags': ad_frags,
+        }
+
+        self._prepare_and_start_frag_download(ctx)
+
+        fragment_retries = self.params.get('fragment_retries', 0)
+        skip_unavailable_fragments = self.params.get('skip_unavailable_fragments', True)
+        test = self.params.get('test', False)
+
+        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 = {}
+        frag_index = 0
+        ad_frag_next = False
+        for line in s.splitlines():
+            line = line.strip()
+            if line:
+                if not line.startswith('#'):
+                    if ad_frag_next:
+                        ad_frag_next = False
+                        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)
+                    count = 0
+                    headers = info_dict.get('http_headers', {})
+                    if byte_range:
+                        headers['Range'] = 'bytes=%d-%d' % (byte_range['start'], byte_range['end'])
+                    while count <= fragment_retries:
+                        try:
+                            success, frag_content = self._download_fragment(
+                                ctx, frag_url, info_dict, headers)
+                            if not success:
+                                return False
+                            break
+                        except compat_urllib_error.HTTPError as err:
+                            # Unavailable (possibly temporary) fragments may be served.
+                            # First we try to retry then either skip or abort.
+                            # See https://github.com/rg3/youtube-dl/issues/10165,
+                            # https://github.com/rg3/youtube-dl/issues/10448).
+                            count += 1
+                            if count <= fragment_retries:
+                                self.report_retry_fragment(err, frag_index, count, fragment_retries)
+                    if count > fragment_retries:
+                        if skip_unavailable_fragments:
+                            i += 1
+                            media_sequence += 1
+                            self.report_skip_fragment(frag_index)
+                            continue
+                        self.report_error(
+                            'giving up after %s fragment retries' % fragment_retries)
+                        return False
+                    if decrypt_info['METHOD'] == 'AES-128':
+                        iv = decrypt_info.get('IV') or compat_struct_pack('>8xq', media_sequence)
+                        decrypt_info['KEY'] = decrypt_info.get('KEY') or self.ydl.urlopen(
+                            self._prepare_url(info_dict, decrypt_info['URI'])).read()
+                        frag_content = AES.new(
+                            decrypt_info['KEY'], AES.MODE_CBC, iv).decrypt(frag_content)
+                    self._append_fragment(ctx, frag_content)
+                    # We only download the first fragment during the test
+                    if test:
+                        break
+                    i += 1
+                    media_sequence += 1
+                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(line):
+                    ad_frag_next = True
+
+        self._finish_frag_download(ctx)
+
+        return True
diff --git a/youtube_dl/downloader/http.py b/youtube_dl/downloader/http.py
new file mode 100644
index 0000000..5b1e960
--- /dev/null
+++ b/youtube_dl/downloader/http.py
@@ -0,0 +1,354 @@
+from __future__ import unicode_literals
+
+import errno
+import os
+import socket
+import time
+import random
+import re
+
+from .common import FileDownloader
+from ..compat import (
+    compat_str,
+    compat_urllib_error,
+)
+from ..utils import (
+    ContentTooShortError,
+    encodeFilename,
+    int_or_none,
+    sanitize_open,
+    sanitized_Request,
+    write_xattr,
+    XAttrMetadataError,
+    XAttrUnavailableError,
+)
+
+
+class HttpFD(FileDownloader):
+    def real_download(self, filename, info_dict):
+        url = info_dict['url']
+
+        class DownloadContext(dict):
+            __getattr__ = dict.get
+            __setattr__ = dict.__setitem__
+            __delattr__ = dict.__delitem__
+
+        ctx = DownloadContext()
+        ctx.filename = filename
+        ctx.tmpfilename = self.temp_name(filename)
+        ctx.stream = None
+
+        # Do not include the Accept-Encoding header
+        headers = {'Youtubedl-no-compression': 'True'}
+        add_headers = info_dict.get('http_headers')
+        if add_headers:
+            headers.update(add_headers)
+
+        is_test = self.params.get('test', False)
+        chunk_size = self._TEST_FILE_SIZE if is_test else (
+            info_dict.get('downloader_options', {}).get('http_chunk_size') or
+            self.params.get('http_chunk_size') or 0)
+
+        ctx.open_mode = 'wb'
+        ctx.resume_len = 0
+        ctx.data_len = None
+        ctx.block_size = self.params.get('buffersize', 1024)
+        ctx.start_time = time.time()
+        ctx.chunk_size = None
+
+        if self.params.get('continuedl', True):
+            # Establish possible resume length
+            if os.path.isfile(encodeFilename(ctx.tmpfilename)):
+                ctx.resume_len = os.path.getsize(
+                    encodeFilename(ctx.tmpfilename))
+
+        ctx.is_resume = ctx.resume_len > 0
+
+        count = 0
+        retries = self.params.get('retries', 0)
+
+        class SucceedDownload(Exception):
+            pass
+
+        class RetryDownload(Exception):
+            def __init__(self, source_error):
+                self.source_error = source_error
+
+        class NextFragment(Exception):
+            pass
+
+        def set_range(req, start, end):
+            range_header = 'bytes=%d-' % start
+            if end:
+                range_header += compat_str(end)
+            req.add_header('Range', range_header)
+
+        def establish_connection():
+            ctx.chunk_size = (random.randint(int(chunk_size * 0.95), chunk_size)
+                              if not is_test and chunk_size else chunk_size)
+            if ctx.resume_len > 0:
+                range_start = ctx.resume_len
+                if ctx.is_resume:
+                    self.report_resuming_byte(ctx.resume_len)
+                ctx.open_mode = 'ab'
+            elif ctx.chunk_size > 0:
+                range_start = 0
+            else:
+                range_start = None
+            ctx.is_resume = False
+            range_end = range_start + ctx.chunk_size - 1 if ctx.chunk_size else None
+            if range_end and ctx.data_len is not None and range_end >= ctx.data_len:
+                range_end = ctx.data_len - 1
+            has_range = range_start is not None
+            ctx.has_range = has_range
+            request = sanitized_Request(url, None, headers)
+            if has_range:
+                set_range(request, range_start, range_end)
+            # Establish connection
+            try:
+                ctx.data = self.ydl.urlopen(request)
+                # When trying to resume, Content-Range HTTP header of response has to be checked
+                # to match the value of requested Range HTTP header. This is due to a webservers
+                # that don't support resuming and serve a whole file with no Content-Range
+                # set in response despite of requested Range (see
+                # https://github.com/rg3/youtube-dl/issues/6057#issuecomment-126129799)
+                if has_range:
+                    content_range = ctx.data.headers.get('Content-Range')
+                    if content_range:
+                        content_range_m = re.search(r'bytes (\d+)-(\d+)?(?:/(\d+))?', content_range)
+                        # Content-Range is present and matches requested Range, resume is possible
+                        if content_range_m:
+                            if range_start == int(content_range_m.group(1)):
+                                content_range_end = int_or_none(content_range_m.group(2))
+                                content_len = int_or_none(content_range_m.group(3))
+                                accept_content_len = (
+                                    # Non-chunked download
+                                    not ctx.chunk_size or
+                                    # Chunked download and requested piece or
+                                    # its part is promised to be served
+                                    content_range_end == range_end or
+                                    content_len < range_end)
+                                if accept_content_len:
+                                    ctx.data_len = content_len
+                                    return
+                    # Content-Range is either not present or invalid. Assuming remote webserver is
+                    # trying to send the whole file, resume is not possible, so wiping the local file
+                    # and performing entire redownload
+                    self.report_unable_to_resume()
+                    ctx.resume_len = 0
+                    ctx.open_mode = 'wb'
+                ctx.data_len = int_or_none(ctx.data.info().get('Content-length', None))
+                return
+            except (compat_urllib_error.HTTPError, ) as err:
+                if err.code == 416:
+                    # Unable to resume (requested range not satisfiable)
+                    try:
+                        # Open the connection again without the range header
+                        ctx.data = self.ydl.urlopen(
+                            sanitized_Request(url, None, headers))
+                        content_length = ctx.data.info()['Content-Length']
+                    except (compat_urllib_error.HTTPError, ) as err:
+                        if err.code < 500 or err.code >= 600:
+                            raise
+                    else:
+                        # Examine the reported length
+                        if (content_length is not None and
+                                (ctx.resume_len - 100 < int(content_length) < ctx.resume_len + 100)):
+                            # The file had already been fully downloaded.
+                            # Explanation to the above condition: in issue #175 it was revealed that
+                            # YouTube sometimes adds or removes a few bytes from the end of the file,
+                            # changing the file size slightly and causing problems for some users. So
+                            # I decided to implement a suggested change and consider the file
+                            # completely downloaded if the file size differs less than 100 bytes from
+                            # the one in the hard drive.
+                            self.report_file_already_downloaded(ctx.filename)
+                            self.try_rename(ctx.tmpfilename, ctx.filename)
+                            self._hook_progress({
+                                'filename': ctx.filename,
+                                'status': 'finished',
+                                'downloaded_bytes': ctx.resume_len,
+                                'total_bytes': ctx.resume_len,
+                            })
+                            raise SucceedDownload()
+                        else:
+                            # The length does not match, we start the download over
+                            self.report_unable_to_resume()
+                            ctx.resume_len = 0
+                            ctx.open_mode = 'wb'
+                            return
+                elif err.code < 500 or err.code >= 600:
+                    # Unexpected HTTP error
+                    raise
+                raise RetryDownload(err)
+            except socket.error as err:
+                if err.errno != errno.ECONNRESET:
+                    # Connection reset is no problem, just retry
+                    raise
+                raise RetryDownload(err)
+
+        def download():
+            data_len = ctx.data.info().get('Content-length', None)
+
+            # Range HTTP header may be ignored/unsupported by a webserver
+            # (e.g. extractor/scivee.py, extractor/bambuser.py).
+            # However, for a test we still would like to download just a piece of a file.
+            # To achieve this we limit data_len to _TEST_FILE_SIZE and manually control
+            # block size when downloading a file.
+            if is_test and (data_len is None or int(data_len) > self._TEST_FILE_SIZE):
+                data_len = self._TEST_FILE_SIZE
+
+            if data_len is not None:
+                data_len = int(data_len) + ctx.resume_len
+                min_data_len = self.params.get('min_filesize')
+                max_data_len = self.params.get('max_filesize')
+                if min_data_len is not None and data_len < min_data_len:
+                    self.to_screen('\r[download] File is smaller than min-filesize (%s bytes < %s bytes). Aborting.' % (data_len, min_data_len))
+                    return False
+                if max_data_len is not None and data_len > max_data_len:
+                    self.to_screen('\r[download] File is larger than max-filesize (%s bytes > %s bytes). Aborting.' % (data_len, max_data_len))
+                    return False
+
+            byte_counter = 0 + ctx.resume_len
+            block_size = ctx.block_size
+            start = time.time()
+
+            # measure time over whole while-loop, so slow_down() and best_block_size() work together properly
+            now = None  # needed for slow_down() in the first loop run
+            before = start  # start measuring
+
+            def retry(e):
+                to_stdout = ctx.tmpfilename == '-'
+                if not to_stdout:
+                    ctx.stream.close()
+                ctx.stream = None
+                ctx.resume_len = byte_counter if to_stdout else os.path.getsize(encodeFilename(ctx.tmpfilename))
+                raise RetryDownload(e)
+
+            while True:
+                try:
+                    # Download and write
+                    data_block = ctx.data.read(block_size if not is_test else min(block_size, data_len - byte_counter))
+                # socket.timeout is a subclass of socket.error but may not have
+                # errno set
+                except socket.timeout as e:
+                    retry(e)
+                except socket.error as e:
+                    if e.errno not in (errno.ECONNRESET, errno.ETIMEDOUT):
+                        raise
+                    retry(e)
+
+                byte_counter += len(data_block)
+
+                # exit loop when download is finished
+                if len(data_block) == 0:
+                    break
+
+                # Open destination file just in time
+                if ctx.stream is None:
+                    try:
+                        ctx.stream, ctx.tmpfilename = sanitize_open(
+                            ctx.tmpfilename, ctx.open_mode)
+                        assert ctx.stream is not None
+                        ctx.filename = self.undo_temp_name(ctx.tmpfilename)
+                        self.report_destination(ctx.filename)
+                    except (OSError, IOError) as err:
+                        self.report_error('unable to open for writing: %s' % str(err))
+                        return False
+
+                    if self.params.get('xattr_set_filesize', False) and data_len is not None:
+                        try:
+                            write_xattr(ctx.tmpfilename, 'user.ytdl.filesize', str(data_len).encode('utf-8'))
+                        except (XAttrUnavailableError, XAttrMetadataError) as err:
+                            self.report_error('unable to set filesize xattr: %s' % str(err))
+
+                try:
+                    ctx.stream.write(data_block)
+                except (IOError, OSError) as err:
+                    self.to_stderr('\n')
+                    self.report_error('unable to write data: %s' % str(err))
+                    return False
+
+                # Apply rate limit
+                self.slow_down(start, now, byte_counter - ctx.resume_len)
+
+                # end measuring of one loop run
+                now = time.time()
+                after = now
+
+                # Adjust block size
+                if not self.params.get('noresizebuffer', False):
+                    block_size = self.best_block_size(after - before, len(data_block))
+
+                before = after
+
+                # Progress message
+                speed = self.calc_speed(start, now, byte_counter - ctx.resume_len)
+                if ctx.data_len is None:
+                    eta = None
+                else:
+                    eta = self.calc_eta(start, time.time(), ctx.data_len - ctx.resume_len, byte_counter - ctx.resume_len)
+
+                self._hook_progress({
+                    'status': 'downloading',
+                    'downloaded_bytes': byte_counter,
+                    'total_bytes': ctx.data_len,
+                    'tmpfilename': ctx.tmpfilename,
+                    'filename': ctx.filename,
+                    'eta': eta,
+                    'speed': speed,
+                    'elapsed': now - ctx.start_time,
+                })
+
+                if is_test and byte_counter == data_len:
+                    break
+
+            if not is_test and ctx.chunk_size and ctx.data_len is not None and byte_counter < ctx.data_len:
+                ctx.resume_len = byte_counter
+                # ctx.block_size = block_size
+                raise NextFragment()
+
+            if ctx.stream is None:
+                self.to_stderr('\n')
+                self.report_error('Did not get any data blocks')
+                return False
+            if ctx.tmpfilename != '-':
+                ctx.stream.close()
+
+            if data_len is not None and byte_counter != data_len:
+                err = ContentTooShortError(byte_counter, int(data_len))
+                if count <= retries:
+                    retry(err)
+                raise err
+
+            self.try_rename(ctx.tmpfilename, ctx.filename)
+
+            # Update file modification time
+            if self.params.get('updatetime', True):
+                info_dict['filetime'] = self.try_utime(ctx.filename, ctx.data.info().get('last-modified', None))
+
+            self._hook_progress({
+                'downloaded_bytes': byte_counter,
+                'total_bytes': byte_counter,
+                'filename': ctx.filename,
+                'status': 'finished',
+                'elapsed': time.time() - ctx.start_time,
+            })
+
+            return True
+
+        while count <= retries:
+            try:
+                establish_connection()
+                return download()
+            except RetryDownload as e:
+                count += 1
+                if count <= retries:
+                    self.report_retry(e.source_error, count, retries)
+                continue
+            except NextFragment:
+                continue
+            except SucceedDownload:
+                return True
+
+        self.report_error('giving up after %s retries' % retries)
+        return False
diff --git a/youtube_dl/downloader/ism.py b/youtube_dl/downloader/ism.py
new file mode 100644
index 0000000..063fcf4
--- /dev/null
+++ b/youtube_dl/downloader/ism.py
@@ -0,0 +1,259 @@
+from __future__ import unicode_literals
+
+import time
+import binascii
+import io
+
+from .fragment import FragmentFD
+from ..compat import (
+    compat_Struct,
+    compat_urllib_error,
+)
+
+
+u8 = compat_Struct('>B')
+u88 = compat_Struct('>Bx')
+u16 = compat_Struct('>H')
+u1616 = compat_Struct('>Hxx')
+u32 = compat_Struct('>I')
+u64 = compat_Struct('>Q')
+
+s88 = compat_Struct('>bx')
+s16 = compat_Struct('>h')
+s1616 = compat_Struct('>hxx')
+s32 = compat_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)
+    is_audio = width == 0 and height == 0
+    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 is_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
+    hdlr_payload += b'soun' if is_audio else b'vide'  # handler type
+    hdlr_payload += u32.pack(0) * 3  # reserved
+    hdlr_payload += (b'Sound' if is_audio else b'Video') + b'Handler\0'  # name
+    mdia_payload += full_box(b'hdlr', 0, 0, hdlr_payload)  # Handler Reference Box
+
+    if is_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
+    else:
+        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
+    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 is_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)
+    else:
+        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('utf-8'))
+        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 represenation (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
+    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)
+
+        fragment_retries = self.params.get('fragment_retries', 0)
+        skip_unavailable_fragments = self.params.get('skip_unavailable_fragments', True)
+
+        track_written = False
+        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, frag_content = self._download_fragment(ctx, segment['url'], info_dict)
+                    if not success:
+                        return False
+                    if not 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'])
+                        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)
+
+        return True
diff --git a/youtube_dl/downloader/rtmp.py b/youtube_dl/downloader/rtmp.py
new file mode 100644
index 0000000..fbb7f51
--- /dev/null
+++ b/youtube_dl/downloader/rtmp.py
@@ -0,0 +1,214 @@
+from __future__ import unicode_literals
+
+import os
+import re
+import subprocess
+import time
+
+from .common import FileDownloader
+from ..compat import compat_str
+from ..utils import (
+    check_executable,
+    encodeFilename,
+    encodeArgument,
+    get_exe_version,
+)
+
+
+def rtmpdump_version():
+    return get_exe_version(
+        'rtmpdump', ['--help'], r'(?i)RTMPDump\s*v?([0-9a-zA-Z._-]+)')
+
+
+class RtmpFD(FileDownloader):
+    def real_download(self, filename, info_dict):
+        def run_rtmpdump(args):
+            start = time.time()
+            resume_percent = None
+            resume_downloaded_data_len = None
+            proc = subprocess.Popen(args, stderr=subprocess.PIPE)
+            cursor_in_new_line = True
+            proc_stderr_closed = False
+            try:
+                while not proc_stderr_closed:
+                    # read line from stderr
+                    line = ''
+                    while True:
+                        char = proc.stderr.read(1)
+                        if not char:
+                            proc_stderr_closed = True
+                            break
+                        if char in [b'\r', b'\n']:
+                            break
+                        line += char.decode('ascii', 'replace')
+                    if not line:
+                        # proc_stderr_closed is True
+                        continue
+                    mobj = re.search(r'([0-9]+\.[0-9]{3}) kB / [0-9]+\.[0-9]{2} sec \(([0-9]{1,2}\.[0-9])%\)', line)
+                    if mobj:
+                        downloaded_data_len = int(float(mobj.group(1)) * 1024)
+                        percent = float(mobj.group(2))
+                        if not resume_percent:
+                            resume_percent = percent
+                            resume_downloaded_data_len = downloaded_data_len
+                        time_now = time.time()
+                        eta = self.calc_eta(start, time_now, 100 - resume_percent, percent - resume_percent)
+                        speed = self.calc_speed(start, time_now, downloaded_data_len - resume_downloaded_data_len)
+                        data_len = None
+                        if percent > 0:
+                            data_len = int(downloaded_data_len * 100 / percent)
+                        self._hook_progress({
+                            'status': 'downloading',
+                            'downloaded_bytes': downloaded_data_len,
+                            'total_bytes_estimate': data_len,
+                            'tmpfilename': tmpfilename,
+                            'filename': filename,
+                            'eta': eta,
+                            'elapsed': time_now - start,
+                            'speed': speed,
+                        })
+                        cursor_in_new_line = False
+                    else:
+                        # no percent for live streams
+                        mobj = re.search(r'([0-9]+\.[0-9]{3}) kB / [0-9]+\.[0-9]{2} sec', line)
+                        if mobj:
+                            downloaded_data_len = int(float(mobj.group(1)) * 1024)
+                            time_now = time.time()
+                            speed = self.calc_speed(start, time_now, downloaded_data_len)
+                            self._hook_progress({
+                                'downloaded_bytes': downloaded_data_len,
+                                'tmpfilename': tmpfilename,
+                                'filename': filename,
+                                'status': 'downloading',
+                                'elapsed': time_now - start,
+                                'speed': speed,
+                            })
+                            cursor_in_new_line = False
+                        elif self.params.get('verbose', False):
+                            if not cursor_in_new_line:
+                                self.to_screen('')
+                            cursor_in_new_line = True
+                            self.to_screen('[rtmpdump] ' + line)
+            finally:
+                proc.wait()
+            if not cursor_in_new_line:
+                self.to_screen('')
+            return proc.returncode
+
+        url = info_dict['url']
+        player_url = info_dict.get('player_url')
+        page_url = info_dict.get('page_url')
+        app = info_dict.get('app')
+        play_path = info_dict.get('play_path')
+        tc_url = info_dict.get('tc_url')
+        flash_version = info_dict.get('flash_version')
+        live = info_dict.get('rtmp_live', False)
+        conn = info_dict.get('rtmp_conn')
+        protocol = info_dict.get('rtmp_protocol')
+        real_time = info_dict.get('rtmp_real_time', False)
+        no_resume = info_dict.get('no_resume', False)
+        continue_dl = self.params.get('continuedl', True)
+
+        self.report_destination(filename)
+        tmpfilename = self.temp_name(filename)
+        test = self.params.get('test', False)
+
+        # Check for rtmpdump first
+        if not check_executable('rtmpdump', ['-h']):
+            self.report_error('RTMP download detected but "rtmpdump" could not be run. Please install it.')
+            return False
+
+        # Download using rtmpdump. rtmpdump returns exit code 2 when
+        # the connection was interrupted and resuming appears to be
+        # possible. This is part of rtmpdump's normal usage, AFAIK.
+        basic_args = [
+            'rtmpdump', '--verbose', '-r', url,
+            '-o', tmpfilename]
+        if player_url is not None:
+            basic_args += ['--swfVfy', player_url]
+        if page_url is not None:
+            basic_args += ['--pageUrl', page_url]
+        if app is not None:
+            basic_args += ['--app', app]
+        if play_path is not None:
+            basic_args += ['--playpath', play_path]
+        if tc_url is not None:
+            basic_args += ['--tcUrl', tc_url]
+        if test:
+            basic_args += ['--stop', '1']
+        if flash_version is not None:
+            basic_args += ['--flashVer', flash_version]
+        if live:
+            basic_args += ['--live']
+        if isinstance(conn, list):
+            for entry in conn:
+                basic_args += ['--conn', entry]
+        elif isinstance(conn, compat_str):
+            basic_args += ['--conn', conn]
+        if protocol is not None:
+            basic_args += ['--protocol', protocol]
+        if real_time:
+            basic_args += ['--realtime']
+
+        args = basic_args
+        if not no_resume and continue_dl and not live:
+            args += ['--resume']
+        if not live and continue_dl:
+            args += ['--skip', '1']
+
+        args = [encodeArgument(a) for a in args]
+
+        self._debug_cmd(args, exe='rtmpdump')
+
+        RD_SUCCESS = 0
+        RD_FAILED = 1
+        RD_INCOMPLETE = 2
+        RD_NO_CONNECT = 3
+
+        started = time.time()
+
+        try:
+            retval = run_rtmpdump(args)
+        except KeyboardInterrupt:
+            if not info_dict.get('is_live'):
+                raise
+            retval = RD_SUCCESS
+            self.to_screen('\n[rtmpdump] Interrupted by user')
+
+        if retval == RD_NO_CONNECT:
+            self.report_error('[rtmpdump] Could not connect to RTMP server.')
+            return False
+
+        while retval in (RD_INCOMPLETE, RD_FAILED) and not test and not live:
+            prevsize = os.path.getsize(encodeFilename(tmpfilename))
+            self.to_screen('[rtmpdump] Downloaded %s bytes' % prevsize)
+            time.sleep(5.0)  # This seems to be needed
+            args = basic_args + ['--resume']
+            if retval == RD_FAILED:
+                args += ['--skip', '1']
+            args = [encodeArgument(a) for a in args]
+            retval = run_rtmpdump(args)
+            cursize = os.path.getsize(encodeFilename(tmpfilename))
+            if prevsize == cursize and retval == RD_FAILED:
+                break
+            # Some rtmp streams seem abort after ~ 99.8%. Don't complain for those
+            if prevsize == cursize and retval == RD_INCOMPLETE and cursize > 1024:
+                self.to_screen('[rtmpdump] Could not download the whole video. This can happen for some advertisements.')
+                retval = RD_SUCCESS
+                break
+        if retval == RD_SUCCESS or (test and retval == RD_INCOMPLETE):
+            fsize = os.path.getsize(encodeFilename(tmpfilename))
+            self.to_screen('[rtmpdump] Downloaded %s bytes' % fsize)
+            self.try_rename(tmpfilename, filename)
+            self._hook_progress({
+                'downloaded_bytes': fsize,
+                'total_bytes': fsize,
+                'filename': filename,
+                'status': 'finished',
+                'elapsed': time.time() - started,
+            })
+            return True
+        else:
+            self.to_stderr('\n')
+            self.report_error('rtmpdump exited with code %d' % retval)
+            return False
diff --git a/youtube_dl/downloader/rtsp.py b/youtube_dl/downloader/rtsp.py
new file mode 100644
index 0000000..939358b
--- /dev/null
+++ b/youtube_dl/downloader/rtsp.py
@@ -0,0 +1,47 @@
+from __future__ import unicode_literals
+
+import os
+import subprocess
+
+from .common import FileDownloader
+from ..utils import (
+    check_executable,
+    encodeFilename,
+)
+
+
+class RtspFD(FileDownloader):
+    def real_download(self, filename, info_dict):
+        url = info_dict['url']
+        self.report_destination(filename)
+        tmpfilename = self.temp_name(filename)
+
+        if check_executable('mplayer', ['-h']):
+            args = [
+                'mplayer', '-really-quiet', '-vo', 'null', '-vc', 'dummy',
+                '-dumpstream', '-dumpfile', tmpfilename, url]
+        elif check_executable('mpv', ['-h']):
+            args = [
+                'mpv', '-really-quiet', '--vo=null', '--stream-dump=' + tmpfilename, url]
+        else:
+            self.report_error('MMS or RTSP download detected but neither "mplayer" nor "mpv" could be run. Please install any.')
+            return False
+
+        self._debug_cmd(args)
+
+        retval = subprocess.call(args)
+        if retval == 0:
+            fsize = os.path.getsize(encodeFilename(tmpfilename))
+            self.to_screen('\r[%s] %s bytes' % (args[0], fsize))
+            self.try_rename(tmpfilename, filename)
+            self._hook_progress({
+                'downloaded_bytes': fsize,
+                'total_bytes': fsize,
+                'filename': filename,
+                'status': 'finished',
+            })
+            return True
+        else:
+            self.to_stderr('\n')
+            self.report_error('%s exited with code %d' % (args[0], retval))
+            return False