Stream descriptors
^^^^^^^^^^^^^^^^^^

There can be multiple *stream_descriptor* with input from the same "file" or
multiple different "files".

Stream descriptor is of the form::

    <field>=<value>[,<field>=<value>]...

These are the available fields:

:input (in):

    input/source media "file" path, which can be regular files, pipes, udp
    streams. See :doc:`/options/udp_file_options` on additional options for UDP
    files.

:stream_selector (stream):

    Required field with value 'audio', 'video', 'text' or stream number (zero
    based).

:output (out):

    Required output file path (single file).

:init_segment:

    initialization segment path (multiple file).

:segment_template (segment):

    Optional value which specifies the naming  pattern for the segment files,
    and that the stream should be split into multiple files. Its presence should
    be consistent across streams. See
    :doc:`/options/segment_template_formatting`.

:bandwidth (bw):

    Optional value which contains a user-specified maximum bit rate for the
    stream, in bits/sec. If specified, this value is propagated to (HLS)
    EXT-X-STREAM-INF:BANDWIDTH or (DASH) Representation@bandwidth and the
    $Bandwidth$ template parameter for segment names. If not specified, the
    bandwidth value is estimated from content bitrate. Note that it only affects
    the generated manifests/playlists; it has no effect on the media content
    itself.

:language (lang):

    Optional value which contains a user-specified language tag. If specified,
    this value overrides any language metadata in the input stream.

:output_format (format):

    Optional value which specifies the format of the output files (MP4 or WebM).
    If not specified, it will be derived from the file extension of the output
    file.

:trick_play_factor (tpf):

    Optional value which specifies the trick play, a.k.a. trick mode, stream
    sampling rate among key frames. If specified, the output is a trick play
    stream.

.. include:: /options/drm_stream_descriptors.rst
.. include:: /options/dash_stream_descriptors.rst
.. include:: /options/hls_stream_descriptors.rst