Provided by: ffmpeg_3.3.4-2_amd64 bug

NAME

       ffmpeg-formats - FFmpeg formats

DESCRIPTION

       This document describes the supported formats (muxers and demuxers) provided by the
       libavformat library.

FORMAT OPTIONS

       The libavformat library provides some generic global options, which can be set on all the
       muxers and demuxers. In addition each muxer or demuxer may support so-called private
       options, which are specific for that component.

       Options may be set by specifying -option value in the FFmpeg tools, or by setting the
       value explicitly in the "AVFormatContext" options or using the libavutil/opt.h API for
       programmatic use.

       The list of supported options follows:

       avioflags flags (input/output)
           Possible values:

           direct
               Reduce buffering.

       probesize integer (input)
           Set probing size in bytes, i.e. the size of the data to analyze to get stream
           information. A higher value will enable detecting more information in case it is
           dispersed into the stream, but will increase latency. Must be an integer not lesser
           than 32. It is 5000000 by default.

       packetsize integer (output)
           Set packet size.

       fflags flags (input/output)
           Set format flags.

           Possible values:

           ignidx
               Ignore index.

           fastseek
               Enable fast, but inaccurate seeks for some formats.

           genpts
               Generate PTS.

           nofillin
               Do not fill in missing values that can be exactly calculated.

           noparse
               Disable AVParsers, this needs "+nofillin" too.

           igndts
               Ignore DTS.

           discardcorrupt
               Discard corrupted frames.

           sortdts
               Try to interleave output packets by DTS.

           keepside
               Do not merge side data.

           latm
               Enable RTP MP4A-LATM payload.

           nobuffer
               Reduce the latency introduced by optional buffering

           bitexact
               Only write platform-, build- and time-independent data.  This ensures that file
               and data checksums are reproducible and match between platforms. Its primary use
               is for regression testing.

           shortest
               Stop muxing at the end of the shortest stream.  It may be needed to increase
               max_interleave_delta to avoid flushing the longer streams before EOF.

       seek2any integer (input)
           Allow seeking to non-keyframes on demuxer level when supported if set to 1.  Default
           is 0.

       analyzeduration integer (input)
           Specify how many microseconds are analyzed to probe the input. A higher value will
           enable detecting more accurate information, but will increase latency. It defaults to
           5,000,000 microseconds = 5 seconds.

       cryptokey hexadecimal string (input)
           Set decryption key.

       indexmem integer (input)
           Set max memory used for timestamp index (per stream).

       rtbufsize integer (input)
           Set max memory used for buffering real-time frames.

       fdebug flags (input/output)
           Print specific debug info.

           Possible values:

           ts
       max_delay integer (input/output)
           Set maximum muxing or demuxing delay in microseconds.

       fpsprobesize integer (input)
           Set number of frames used to probe fps.

       audio_preload integer (output)
           Set microseconds by which audio packets should be interleaved earlier.

       chunk_duration integer (output)
           Set microseconds for each chunk.

       chunk_size integer (output)
           Set size in bytes for each chunk.

       err_detect, f_err_detect flags (input)
           Set error detection flags. "f_err_detect" is deprecated and should be used only via
           the ffmpeg tool.

           Possible values:

           crccheck
               Verify embedded CRCs.

           bitstream
               Detect bitstream specification deviations.

           buffer
               Detect improper bitstream length.

           explode
               Abort decoding on minor error detection.

           careful
               Consider things that violate the spec and have not been seen in the wild as
               errors.

           compliant
               Consider all spec non compliancies as errors.

           aggressive
               Consider things that a sane encoder should not do as an error.

       max_interleave_delta integer (output)
           Set maximum buffering duration for interleaving. The duration is expressed in
           microseconds, and defaults to 1000000 (1 second).

           To ensure all the streams are interleaved correctly, libavformat will wait until it
           has at least one packet for each stream before actually writing any packets to the
           output file. When some streams are "sparse" (i.e. there are large gaps between
           successive packets), this can result in excessive buffering.

           This field specifies the maximum difference between the timestamps of the first and
           the last packet in the muxing queue, above which libavformat will output a packet
           regardless of whether it has queued a packet for all the streams.

           If set to 0, libavformat will continue buffering packets until it has a packet for
           each stream, regardless of the maximum timestamp difference between the buffered
           packets.

       use_wallclock_as_timestamps integer (input)
           Use wallclock as timestamps if set to 1. Default is 0.

       avoid_negative_ts integer (output)
           Possible values:

           make_non_negative
               Shift timestamps to make them non-negative.  Also note that this affects only
               leading negative timestamps, and not non-monotonic negative timestamps.

           make_zero
               Shift timestamps so that the first timestamp is 0.

           auto (default)
               Enables shifting when required by the target format.

           disabled
               Disables shifting of timestamp.

           When shifting is enabled, all output timestamps are shifted by the same amount. Audio,
           video, and subtitles desynching and relative timestamp differences are preserved
           compared to how they would have been without shifting.

       skip_initial_bytes integer (input)
           Set number of bytes to skip before reading header and frames if set to 1.  Default is
           0.

       correct_ts_overflow integer (input)
           Correct single timestamp overflows if set to 1. Default is 1.

       flush_packets integer (output)
           Flush the underlying I/O stream after each packet. Default 1 enables it, and has the
           effect of reducing the latency; 0 disables it and may slightly increase performance in
           some cases.

       output_ts_offset offset (output)
           Set the output time offset.

           offset must be a time duration specification, see the Time duration section in the
           ffmpeg-utils(1) manual.

           The offset is added by the muxer to the output timestamps.

           Specifying a positive offset means that the corresponding streams are delayed bt the
           time duration specified in offset. Default value is 0 (meaning that no offset is
           applied).

       format_whitelist list (input)
           "," separated list of allowed demuxers. By default all are allowed.

       dump_separator string (input)
           Separator used to separate the fields printed on the command line about the Stream
           parameters.  For example to separate the fields with newlines and indention:

                   ffprobe -dump_separator "
                                             "  -i ~/videos/matrixbench_mpeg2.mpg

       max_streams integer (input)
           Specifies the maximum number of streams. This can be used to reject files that would
           require too many resources due to a large number of streams.

   Format stream specifiers
       Format stream specifiers allow selection of one or more streams that match specific
       properties.

       Possible forms of stream specifiers are:

       stream_index
           Matches the stream with this index.

       stream_type[:stream_index]
           stream_type is one of following: 'v' for video, 'a' for audio, 's' for subtitle, 'd'
           for data, and 't' for attachments. If stream_index is given, then it matches the
           stream number stream_index of this type. Otherwise, it matches all streams of this
           type.

       p:program_id[:stream_index]
           If stream_index is given, then it matches the stream with number stream_index in the
           program with the id program_id. Otherwise, it matches all streams in the program.

       #stream_id
           Matches the stream by a format-specific ID.

       The exact semantics of stream specifiers is defined by the
       "avformat_match_stream_specifier()" function declared in the libavformat/avformat.h
       header.

DEMUXERS

       Demuxers are configured elements in FFmpeg that can read the multimedia streams from a
       particular type of file.

       When you configure your FFmpeg build, all the supported demuxers are enabled by default.
       You can list all available ones using the configure option "--list-demuxers".

       You can disable all the demuxers using the configure option "--disable-demuxers", and
       selectively enable a single demuxer with the option "--enable-demuxer=DEMUXER", or disable
       it with the option "--disable-demuxer=DEMUXER".

       The option "-demuxers" of the ff* tools will display the list of enabled demuxers. Use
       "-formats" to view a combined list of enabled demuxers and muxers.

       The description of some of the currently available demuxers follows.

   aa
       Audible Format 2, 3, and 4 demuxer.

       This demuxer is used to demux Audible Format 2, 3, and 4 (.aa) files.

   applehttp
       Apple HTTP Live Streaming demuxer.

       This demuxer presents all AVStreams from all variant streams.  The id field is set to the
       bitrate variant index number. By setting the discard flags on AVStreams (by pressing 'a'
       or 'v' in ffplay), the caller can decide which variant streams to actually receive.  The
       total bitrate of the variant that the stream belongs to is available in a metadata key
       named "variant_bitrate".

   apng
       Animated Portable Network Graphics demuxer.

       This demuxer is used to demux APNG files.  All headers, but the PNG signature, up to (but
       not including) the first fcTL chunk are transmitted as extradata.  Frames are then split
       as being all the chunks between two fcTL ones, or between the last fcTL and IEND chunks.

       -ignore_loop bool
           Ignore the loop variable in the file if set.

       -max_fps int
           Maximum framerate in frames per second (0 for no limit).

       -default_fps int
           Default framerate in frames per second when none is specified in the file (0 meaning
           as fast as possible).

   asf
       Advanced Systems Format demuxer.

       This demuxer is used to demux ASF files and MMS network streams.

       -no_resync_search bool
           Do not try to resynchronize by looking for a certain optional start code.

   concat
       Virtual concatenation script demuxer.

       This demuxer reads a list of files and other directives from a text file and demuxes them
       one after the other, as if all their packets had been muxed together.

       The timestamps in the files are adjusted so that the first file starts at 0 and each next
       file starts where the previous one finishes. Note that it is done globally and may cause
       gaps if all streams do not have exactly the same length.

       All files must have the same streams (same codecs, same time base, etc.).

       The duration of each file is used to adjust the timestamps of the next file: if the
       duration is incorrect (because it was computed using the bit-rate or because the file is
       truncated, for example), it can cause artifacts. The "duration" directive can be used to
       override the duration stored in each file.

       Syntax

       The script is a text file in extended-ASCII, with one directive per line.  Empty lines,
       leading spaces and lines starting with '#' are ignored. The following directive is
       recognized:

       "file path"
           Path to a file to read; special characters and spaces must be escaped with backslash
           or single quotes.

           All subsequent file-related directives apply to that file.

       "ffconcat version 1.0"
           Identify the script type and version. It also sets the safe option to 1 if it was -1.

           To make FFmpeg recognize the format automatically, this directive must appear exactly
           as is (no extra space or byte-order-mark) on the very first line of the script.

       "duration dur"
           Duration of the file. This information can be specified from the file; specifying it
           here may be more efficient or help if the information from the file is not available
           or accurate.

           If the duration is set for all files, then it is possible to seek in the whole
           concatenated video.

       "inpoint timestamp"
           In point of the file. When the demuxer opens the file it instantly seeks to the
           specified timestamp. Seeking is done so that all streams can be presented successfully
           at In point.

           This directive works best with intra frame codecs, because for non-intra frame ones
           you will usually get extra packets before the actual In point and the decoded content
           will most likely contain frames before In point too.

           For each file, packets before the file In point will have timestamps less than the
           calculated start timestamp of the file (negative in case of the first file), and the
           duration of the files (if not specified by the "duration" directive) will be reduced
           based on their specified In point.

           Because of potential packets before the specified In point, packet timestamps may
           overlap between two concatenated files.

       "outpoint timestamp"
           Out point of the file. When the demuxer reaches the specified decoding timestamp in
           any of the streams, it handles it as an end of file condition and skips the current
           and all the remaining packets from all streams.

           Out point is exclusive, which means that the demuxer will not output packets with a
           decoding timestamp greater or equal to Out point.

           This directive works best with intra frame codecs and formats where all streams are
           tightly interleaved. For non-intra frame codecs you will usually get additional
           packets with presentation timestamp after Out point therefore the decoded content will
           most likely contain frames after Out point too. If your streams are not tightly
           interleaved you may not get all the packets from all streams before Out point and you
           may only will be able to decode the earliest stream until Out point.

           The duration of the files (if not specified by the "duration" directive) will be
           reduced based on their specified Out point.

       "file_packet_metadata key=value"
           Metadata of the packets of the file. The specified metadata will be set for each file
           packet. You can specify this directive multiple times to add multiple metadata
           entries.

       "stream"
           Introduce a stream in the virtual file.  All subsequent stream-related directives
           apply to the last introduced stream.  Some streams properties must be set in order to
           allow identifying the matching streams in the subfiles.  If no streams are defined in
           the script, the streams from the first file are copied.

       "exact_stream_id id"
           Set the id of the stream.  If this directive is given, the string with the
           corresponding id in the subfiles will be used.  This is especially useful for MPEG-PS
           (VOB) files, where the order of the streams is not reliable.

       Options

       This demuxer accepts the following option:

       safe
           If set to 1, reject unsafe file paths. A file path is considered safe if it does not
           contain a protocol specification and is relative and all components only contain
           characters from the portable character set (letters, digits, period, underscore and
           hyphen) and have no period at the beginning of a component.

           If set to 0, any file name is accepted.

           The default is 1.

           -1 is equivalent to 1 if the format was automatically probed and 0 otherwise.

       auto_convert
           If set to 1, try to perform automatic conversions on packet data to make the streams
           concatenable.  The default is 1.

           Currently, the only conversion is adding the h264_mp4toannexb bitstream filter to
           H.264 streams in MP4 format. This is necessary in particular if there are resolution
           changes.

       segment_time_metadata
           If set to 1, every packet will contain the lavf.concat.start_time and the
           lavf.concat.duration packet metadata values which are the start_time and the duration
           of the respective file segments in the concatenated output expressed in microseconds.
           The duration metadata is only set if it is known based on the concat file.  The
           default is 0.

       Examples

       ·   Use absolute filenames and include some comments:

                   # my first filename
                   file /mnt/share/file-1.wav
                   # my second filename including whitespace
                   file '/mnt/share/file 2.wav'
                   # my third filename including whitespace plus single quote
                   file '/mnt/share/file 3'\''.wav'

       ·   Allow for input format auto-probing, use safe filenames and set the duration of the
           first file:

                   ffconcat version 1.0

                   file file-1.wav
                   duration 20.0

                   file subdir/file-2.wav

   flv, live_flv
       Adobe Flash Video Format demuxer.

       This demuxer is used to demux FLV files and RTMP network streams. In case of live network
       streams, if you force format, you may use live_flv option instead of flv to survive
       timestamp discontinuities.

               ffmpeg -f flv -i myfile.flv ...
               ffmpeg -f live_flv -i rtmp://<any.server>/anything/key ....

       -flv_metadata bool
           Allocate the streams according to the onMetaData array content.

   gif
       Animated GIF demuxer.

       It accepts the following options:

       min_delay
           Set the minimum valid delay between frames in hundredths of seconds.  Range is 0 to
           6000. Default value is 2.

       max_gif_delay
           Set the maximum valid delay between frames in hundredth of seconds.  Range is 0 to
           65535. Default value is 65535 (nearly eleven minutes), the maximum value allowed by
           the specification.

       default_delay
           Set the default delay between frames in hundredths of seconds.  Range is 0 to 6000.
           Default value is 10.

       ignore_loop
           GIF files can contain information to loop a certain number of times (or infinitely).
           If ignore_loop is set to 1, then the loop setting from the input will be ignored and
           looping will not occur. If set to 0, then looping will occur and will cycle the number
           of times according to the GIF. Default value is 1.

       For example, with the overlay filter, place an infinitely looping GIF over another video:

               ffmpeg -i input.mp4 -ignore_loop 0 -i input.gif -filter_complex overlay=shortest=1 out.mkv

       Note that in the above example the shortest option for overlay filter is used to end the
       output video at the length of the shortest input file, which in this case is input.mp4 as
       the GIF in this example loops infinitely.

   hls
       HLS demuxer

       It accepts the following options:

       live_start_index
           segment index to start live streams at (negative values are from the end).

       allowed_extensions
           ',' separated list of file extensions that hls is allowed to access.

       max_reload
           Maximum number of times a insufficient list is attempted to be reloaded.  Default
           value is 1000.

   image2
       Image file demuxer.

       This demuxer reads from a list of image files specified by a pattern.  The syntax and
       meaning of the pattern is specified by the option pattern_type.

       The pattern may contain a suffix which is used to automatically determine the format of
       the images contained in the files.

       The size, the pixel format, and the format of each image must be the same for all the
       files in the sequence.

       This demuxer accepts the following options:

       framerate
           Set the frame rate for the video stream. It defaults to 25.

       loop
           If set to 1, loop over the input. Default value is 0.

       pattern_type
           Select the pattern type used to interpret the provided filename.

           pattern_type accepts one of the following values.

           none
               Disable pattern matching, therefore the video will only contain the specified
               image. You should use this option if you do not want to create sequences from
               multiple images and your filenames may contain special pattern characters.

           sequence
               Select a sequence pattern type, used to specify a sequence of files indexed by
               sequential numbers.

               A sequence pattern may contain the string "%d" or "%0Nd", which specifies the
               position of the characters representing a sequential number in each filename
               matched by the pattern. If the form "%d0Nd" is used, the string representing the
               number in each filename is 0-padded and N is the total number of 0-padded digits
               representing the number. The literal character '%' can be specified in the pattern
               with the string "%%".

               If the sequence pattern contains "%d" or "%0Nd", the first filename of the file
               list specified by the pattern must contain a number inclusively contained between
               start_number and start_number+start_number_range-1, and all the following numbers
               must be sequential.

               For example the pattern "img-%03d.bmp" will match a sequence of filenames of the
               form img-001.bmp, img-002.bmp, ..., img-010.bmp, etc.; the pattern
               "i%%m%%g-%d.jpg" will match a sequence of filenames of the form i%m%g-1.jpg,
               i%m%g-2.jpg, ..., i%m%g-10.jpg, etc.

               Note that the pattern must not necessarily contain "%d" or "%0Nd", for example to
               convert a single image file img.jpeg you can employ the command:

                       ffmpeg -i img.jpeg img.png

           glob
               Select a glob wildcard pattern type.

               The pattern is interpreted like a "glob()" pattern. This is only selectable if
               libavformat was compiled with globbing support.

           glob_sequence (deprecated, will be removed)
               Select a mixed glob wildcard/sequence pattern.

               If your version of libavformat was compiled with globbing support, and the
               provided pattern contains at least one glob meta character among "%*?[]{}" that is
               preceded by an unescaped "%", the pattern is interpreted like a "glob()" pattern,
               otherwise it is interpreted like a sequence pattern.

               All glob special characters "%*?[]{}" must be prefixed with "%". To escape a
               literal "%" you shall use "%%".

               For example the pattern "foo-%*.jpeg" will match all the filenames prefixed by
               "foo-" and terminating with ".jpeg", and "foo-%?%?%?.jpeg" will match all the
               filenames prefixed with "foo-", followed by a sequence of three characters, and
               terminating with ".jpeg".

               This pattern type is deprecated in favor of glob and sequence.

           Default value is glob_sequence.

       pixel_format
           Set the pixel format of the images to read. If not specified the pixel format is
           guessed from the first image file in the sequence.

       start_number
           Set the index of the file matched by the image file pattern to start to read from.
           Default value is 0.

       start_number_range
           Set the index interval range to check when looking for the first image file in the
           sequence, starting from start_number. Default value is 5.

       ts_from_file
           If set to 1, will set frame timestamp to modification time of image file. Note that
           monotonity of timestamps is not provided: images go in the same order as without this
           option. Default value is 0.  If set to 2, will set frame timestamp to the modification
           time of the image file in nanosecond precision.

       video_size
           Set the video size of the images to read. If not specified the video size is guessed
           from the first image file in the sequence.

       Examples

       ·   Use ffmpeg for creating a video from the images in the file sequence img-001.jpeg,
           img-002.jpeg, ..., assuming an input frame rate of 10 frames per second:

                   ffmpeg -framerate 10 -i 'img-%03d.jpeg' out.mkv

       ·   As above, but start by reading from a file with index 100 in the sequence:

                   ffmpeg -framerate 10 -start_number 100 -i 'img-%03d.jpeg' out.mkv

       ·   Read images matching the "*.png" glob pattern , that is all the files terminating with
           the ".png" suffix:

                   ffmpeg -framerate 10 -pattern_type glob -i "*.png" out.mkv

   libgme
       The Game Music Emu library is a collection of video game music file emulators.

       See <http://code.google.com/p/game-music-emu/> for more information.

       Some files have multiple tracks. The demuxer will pick the first track by default. The
       track_index option can be used to select a different track. Track indexes start at 0. The
       demuxer exports the number of tracks as tracks meta data entry.

       For very large files, the max_size option may have to be adjusted.

   libopenmpt
       libopenmpt based module demuxer

       See <https://lib.openmpt.org/libopenmpt/> for more information.

       Some files have multiple subsongs (tracks) this can be set with the subsong option.

       It accepts the following options:

       subsong
           Set the subsong index. This can be either  'all', 'auto', or the index of the subsong.
           Subsong indexes start at 0. The default is 'auto'.

           The default value is to let libopenmpt choose.

       layout
           Set the channel layout. Valid values are 1, 2, and 4 channel layouts.  The default
           value is STEREO.

       sample_rate
           Set the sample rate for libopenmpt to output.  Range is from 1000 to INT_MAX. The
           value default is 48000.

   mov/mp4/3gp/QuickTime
       QuickTime / MP4 demuxer.

       This demuxer accepts the following options:

       enable_drefs
           Enable loading of external tracks, disabled by default.  Enabling this can
           theoretically leak information in some use cases.

       use_absolute_path
           Allows loading of external tracks via absolute paths, disabled by default.  Enabling
           this poses a security risk. It should only be enabled if the source is known to be non
           malicious.

   mpegts
       MPEG-2 transport stream demuxer.

       This demuxer accepts the following options:

       resync_size
           Set size limit for looking up a new synchronization. Default value is 65536.

       fix_teletext_pts
           Override teletext packet PTS and DTS values with the timestamps calculated from the
           PCR of the first program which the teletext stream is part of and is not discarded.
           Default value is 1, set this option to 0 if you want your teletext packet PTS and DTS
           values untouched.

       ts_packetsize
           Output option carrying the raw packet size in bytes.  Show the detected raw packet
           size, cannot be set by the user.

       scan_all_pmts
           Scan and combine all PMTs. The value is an integer with value from -1 to 1 (-1 means
           automatic setting, 1 means enabled, 0 means disabled). Default value is -1.

   mpjpeg
       MJPEG encapsulated in multi-part MIME demuxer.

       This demuxer allows reading of MJPEG, where each frame is represented as a part of
       multipart/x-mixed-replace stream.

       strict_mime_boundary
           Default implementation applies a relaxed standard to multi-part MIME boundary
           detection, to prevent regression with numerous existing endpoints not generating a
           proper MIME MJPEG stream. Turning this option on by setting it to 1 will result in a
           stricter check of the boundary value.

   rawvideo
       Raw video demuxer.

       This demuxer allows one to read raw video data. Since there is no header specifying the
       assumed video parameters, the user must specify them in order to be able to decode the
       data correctly.

       This demuxer accepts the following options:

       framerate
           Set input video frame rate. Default value is 25.

       pixel_format
           Set the input video pixel format. Default value is "yuv420p".

       video_size
           Set the input video size. This value must be specified explicitly.

       For example to read a rawvideo file input.raw with ffplay, assuming a pixel format of
       "rgb24", a video size of "320x240", and a frame rate of 10 images per second, use the
       command:

               ffplay -f rawvideo -pixel_format rgb24 -video_size 320x240 -framerate 10 input.raw

   sbg
       SBaGen script demuxer.

       This demuxer reads the script language used by SBaGen <http://uazu.net/sbagen/> to
       generate binaural beats sessions. A SBG script looks like that:

               -SE
               a: 300-2.5/3 440+4.5/0
               b: 300-2.5/0 440+4.5/3
               off: -
               NOW      == a
               +0:07:00 == b
               +0:14:00 == a
               +0:21:00 == b
               +0:30:00    off

       A SBG script can mix absolute and relative timestamps. If the script uses either only
       absolute timestamps (including the script start time) or only relative ones, then its
       layout is fixed, and the conversion is straightforward. On the other hand, if the script
       mixes both kind of timestamps, then the NOW reference for relative timestamps will be
       taken from the current time of day at the time the script is read, and the script layout
       will be frozen according to that reference. That means that if the script is directly
       played, the actual times will match the absolute timestamps up to the sound controller's
       clock accuracy, but if the user somehow pauses the playback or seeks, all times will be
       shifted accordingly.

   tedcaptions
       JSON captions used for <http://www.ted.com/>.

       TED does not provide links to the captions, but they can be guessed from the page. The
       file tools/bookmarklets.html from the FFmpeg source tree contains a bookmarklet to expose
       them.

       This demuxer accepts the following option:

       start_time
           Set the start time of the TED talk, in milliseconds. The default is 15000 (15s). It is
           used to sync the captions with the downloadable videos, because they include a 15s
           intro.

       Example: convert the captions to a format most players understand:

               ffmpeg -i http://www.ted.com/talks/subtitles/id/1/lang/en talk1-en.srt

MUXERS

       Muxers are configured elements in FFmpeg which allow writing multimedia streams to a
       particular type of file.

       When you configure your FFmpeg build, all the supported muxers are enabled by default. You
       can list all available muxers using the configure option "--list-muxers".

       You can disable all the muxers with the configure option "--disable-muxers" and
       selectively enable / disable single muxers with the options "--enable-muxer=MUXER" /
       "--disable-muxer=MUXER".

       The option "-muxers" of the ff* tools will display the list of enabled muxers. Use
       "-formats" to view a combined list of enabled demuxers and muxers.

       A description of some of the currently available muxers follows.

   aiff
       Audio Interchange File Format muxer.

       Options

       It accepts the following options:

       write_id3v2
           Enable ID3v2 tags writing when set to 1. Default is 0 (disabled).

       id3v2_version
           Select ID3v2 version to write. Currently only version 3 and 4 (aka.  ID3v2.3 and
           ID3v2.4) are supported. The default is version 4.

   asf
       Advanced Systems Format muxer.

       Note that Windows Media Audio (wma) and Windows Media Video (wmv) use this muxer too.

       Options

       It accepts the following options:

       packet_size
           Set the muxer packet size. By tuning this setting you may reduce data fragmentation or
           muxer overhead depending on your source. Default value is 3200, minimum is 100,
           maximum is 64k.

   avi
       Audio Video Interleaved muxer.

       Options

       It accepts the following options:

       reserve_index_space
           Reserve the specified amount of bytes for the OpenDML master index of each stream
           within the file header. By default additional master indexes are embedded within the
           data packets if there is no space left in the first master index and are linked
           together as a chain of indexes. This index structure can cause problems for some use
           cases, e.g. third-party software strictly relying on the OpenDML index specification
           or when file seeking is slow. Reserving enough index space in the file header avoids
           these problems.

           The required index space depends on the output file size and should be about 16 bytes
           per gigabyte. When this option is omitted or set to zero the necessary index space is
           guessed.

       write_channel_mask
           Write the channel layout mask into the audio stream header.

           This option is enabled by default. Disabling the channel mask can be useful in
           specific scenarios, e.g. when merging multiple audio streams into one for
           compatibility with software that only supports a single audio stream in AVI (see the
           "amerge" section in the ffmpeg-filters manual).

   chromaprint
       Chromaprint fingerprinter

       This muxer feeds audio data to the Chromaprint library, which generates a fingerprint for
       the provided audio data. It takes a single signed native-endian 16-bit raw audio stream.

       Options

       silence_threshold
           Threshold for detecting silence, ranges from 0 to 32767. -1 for default (required for
           use with the AcoustID service).

       algorithm
           Algorithm index to fingerprint with.

       fp_format
           Format to output the fingerprint as. Accepts the following options:

           raw Binary raw fingerprint

           compressed
               Binary compressed fingerprint

           base64
               Base64 compressed fingerprint

   crc
       CRC (Cyclic Redundancy Check) testing format.

       This muxer computes and prints the Adler-32 CRC of all the input audio and video frames.
       By default audio frames are converted to signed 16-bit raw audio and video frames to raw
       video before computing the CRC.

       The output of the muxer consists of a single line of the form: CRC=0xCRC, where CRC is a
       hexadecimal number 0-padded to 8 digits containing the CRC for all the decoded input
       frames.

       See also the framecrc muxer.

       Examples

       For example to compute the CRC of the input, and store it in the file out.crc:

               ffmpeg -i INPUT -f crc out.crc

       You can print the CRC to stdout with the command:

               ffmpeg -i INPUT -f crc -

       You can select the output format of each frame with ffmpeg by specifying the audio and
       video codec and format. For example to compute the CRC of the input audio converted to PCM
       unsigned 8-bit and the input video converted to MPEG-2 video, use the command:

               ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f crc -

   flv
       Adobe Flash Video Format muxer.

       This muxer accepts the following options:

       flvflags flags
           Possible values:

           aac_seq_header_detect
               Place AAC sequence header based on audio stream data.

           no_sequence_end
               Disable sequence end tag.

           no_metadata
               Disable metadata tag.

           no_duration_filesize
               Disable duration and filesize in metadata when they are equal to zero at the end
               of stream. (Be used to non-seekable living stream).

           add_keyframe_index
               Used to facilitate seeking; particularly for HTTP pseudo streaming.

   framecrc
       Per-packet CRC (Cyclic Redundancy Check) testing format.

       This muxer computes and prints the Adler-32 CRC for each audio and video packet. By
       default audio frames are converted to signed 16-bit raw audio and video frames to raw
       video before computing the CRC.

       The output of the muxer consists of a line for each audio and video packet of the form:

               <stream_index>, <packet_dts>, <packet_pts>, <packet_duration>, <packet_size>, 0x<CRC>

       CRC is a hexadecimal number 0-padded to 8 digits containing the CRC of the packet.

       Examples

       For example to compute the CRC of the audio and video frames in INPUT, converted to raw
       audio and video packets, and store it in the file out.crc:

               ffmpeg -i INPUT -f framecrc out.crc

       To print the information to stdout, use the command:

               ffmpeg -i INPUT -f framecrc -

       With ffmpeg, you can select the output format to which the audio and video frames are
       encoded before computing the CRC for each packet by specifying the audio and video codec.
       For example, to compute the CRC of each decoded input audio frame converted to PCM
       unsigned 8-bit and of each decoded input video frame converted to MPEG-2 video, use the
       command:

               ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -

       See also the crc muxer.

   framehash
       Per-packet hash testing format.

       This muxer computes and prints a cryptographic hash for each audio and video packet. This
       can be used for packet-by-packet equality checks without having to individually do a
       binary comparison on each.

       By default audio frames are converted to signed 16-bit raw audio and video frames to raw
       video before computing the hash, but the output of explicit conversions to other codecs
       can also be used. It uses the SHA-256 cryptographic hash function by default, but supports
       several other algorithms.

       The output of the muxer consists of a line for each audio and video packet of the form:

               <stream_index>, <packet_dts>, <packet_pts>, <packet_duration>, <packet_size>, <hash>

       hash is a hexadecimal number representing the computed hash for the packet.

       hash algorithm
           Use the cryptographic hash function specified by the string algorithm.  Supported
           values include "MD5", "murmur3", "RIPEMD128", "RIPEMD160", "RIPEMD256", "RIPEMD320",
           "SHA160", "SHA224", "SHA256" (default), "SHA512/224", "SHA512/256", "SHA384",
           "SHA512", "CRC32" and "adler32".

       Examples

       To compute the SHA-256 hash of the audio and video frames in INPUT, converted to raw audio
       and video packets, and store it in the file out.sha256:

               ffmpeg -i INPUT -f framehash out.sha256

       To print the information to stdout, using the MD5 hash function, use the command:

               ffmpeg -i INPUT -f framehash -hash md5 -

       See also the hash muxer.

   framemd5
       Per-packet MD5 testing format.

       This is a variant of the framehash muxer. Unlike that muxer, it defaults to using the MD5
       hash function.

       Examples

       To compute the MD5 hash of the audio and video frames in INPUT, converted to raw audio and
       video packets, and store it in the file out.md5:

               ffmpeg -i INPUT -f framemd5 out.md5

       To print the information to stdout, use the command:

               ffmpeg -i INPUT -f framemd5 -

       See also the framehash and md5 muxers.

   gif
       Animated GIF muxer.

       It accepts the following options:

       loop
           Set the number of times to loop the output. Use "-1" for no loop, 0 for looping
           indefinitely (default).

       final_delay
           Force the delay (expressed in centiseconds) after the last frame. Each frame ends with
           a delay until the next frame. The default is "-1", which is a special value to tell
           the muxer to re-use the previous delay. In case of a loop, you might want to customize
           this value to mark a pause for instance.

       For example, to encode a gif looping 10 times, with a 5 seconds delay between the loops:

               ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif

       Note 1: if you wish to extract the frames into separate GIF files, you need to force the
       image2 muxer:

               ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"

       Note 2: the GIF format has a very large time base: the delay between two frames can
       therefore not be smaller than one centi second.

   hash
       Hash testing format.

       This muxer computes and prints a cryptographic hash of all the input audio and video
       frames. This can be used for equality checks without having to do a complete binary
       comparison.

       By default audio frames are converted to signed 16-bit raw audio and video frames to raw
       video before computing the hash, but the output of explicit conversions to other codecs
       can also be used. Timestamps are ignored. It uses the SHA-256 cryptographic hash function
       by default, but supports several other algorithms.

       The output of the muxer consists of a single line of the form: algo=hash, where algo is a
       short string representing the hash function used, and hash is a hexadecimal number
       representing the computed hash.

       hash algorithm
           Use the cryptographic hash function specified by the string algorithm.  Supported
           values include "MD5", "murmur3", "RIPEMD128", "RIPEMD160", "RIPEMD256", "RIPEMD320",
           "SHA160", "SHA224", "SHA256" (default), "SHA512/224", "SHA512/256", "SHA384",
           "SHA512", "CRC32" and "adler32".

       Examples

       To compute the SHA-256 hash of the input converted to raw audio and video, and store it in
       the file out.sha256:

               ffmpeg -i INPUT -f hash out.sha256

       To print an MD5 hash to stdout use the command:

               ffmpeg -i INPUT -f hash -hash md5 -

       See also the framehash muxer.

   hls
       Apple HTTP Live Streaming muxer that segments MPEG-TS according to the HTTP Live Streaming
       (HLS) specification.

       It creates a playlist file, and one or more segment files. The output filename specifies
       the playlist filename.

       By default, the muxer creates a file for each segment produced. These files have the same
       name as the playlist, followed by a sequential number and a .ts extension.

       For example, to convert an input file with ffmpeg:

               ffmpeg -i in.nut out.m3u8

       This example will produce the playlist, out.m3u8, and segment files: out0.ts, out1.ts,
       out2.ts, etc.

       See also the segment muxer, which provides a more generic and flexible implementation of a
       segmenter, and can be used to perform HLS segmentation.

       Options

       This muxer supports the following options:

       hls_init_time seconds
           Set the initial target segment length in seconds. Default value is 0.  Segment will be
           cut on the next key frame after this time has passed on the first m3u8 list.  After
           the initial playlist is filled ffmpeg will cut segments at duration equal to
           "hls_time"

       hls_time seconds
           Set the target segment length in seconds. Default value is 2.  Segment will be cut on
           the next key frame after this time has passed.

       hls_list_size size
           Set the maximum number of playlist entries. If set to 0 the list file will contain all
           the segments. Default value is 5.

       hls_ts_options options_list
           Set output format options using a :-separated list of key=value parameters. Values
           containing ":" special characters must be escaped.

       hls_wrap wrap
           This is a deprecated option, you can use "hls_list_size" and "hls_flags
           delete_segments" instead it

           This option is useful to avoid to fill the disk with many segment files, and limits
           the maximum number of segment files written to disk to wrap.

       hls_start_number_source
           Start the playlist sequence number ("#EXT-X-MEDIA-SEQUENCE") according to the
           specified source.  Unless "hls_flags single_file" is set, it also specifies source of
           starting sequence numbers of segment and subtitle filenames. In any case, if
           "hls_flags append_list" is set and read playlist sequence number is greater than the
           specified start sequence number, then that value will be used as start value.

           It accepts the following values:

           generic (default)
               Set the starting sequence numbers according to start_number option value.

           epoch
               The start number will be the seconds since epoch (1970-01-01 00:00:00)

           datetime
               The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g.
               20161231235759.

       start_number number
           Start the playlist sequence number ("#EXT-X-MEDIA-SEQUENCE") from the specified number
           when hls_start_number_source value is generic. (This is the default case.)  Unless
           "hls_flags single_file" is set, it also specifies starting sequence numbers of segment
           and subtitle filenames.  Default value is 0.

       hls_allow_cache allowcache
           Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.

       hls_base_url baseurl
           Append baseurl to every entry in the playlist.  Useful to generate playlists with
           absolute paths.

           Note that the playlist sequence number must be unique for each segment and it is not
           to be confused with the segment filename sequence number which can be cyclic, for
           example if the wrap option is specified.

       hls_segment_filename filename
           Set the segment filename. Unless "hls_flags single_file" is set, filename is used as a
           string format with the segment number:

                   ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8

           This example will produce the playlist, out.m3u8, and segment files: file000.ts,
           file001.ts, file002.ts, etc.

           filename may contain full path or relative path specification, but only the file name
           part without any path info will be contained in the m3u8 segment list.  Should a
           relative path be specified, the path of the created segment files will be relative to
           the current working directory.  When use_localtime_mkdir is set, the whole expanded
           value of filename will be written into the m3u8 segment list.

       use_localtime
           Use strftime() on filename to expand the segment filename with localtime.  The segment
           number is also available in this mode, but to use it, you need to specify
           second_level_segment_index hls_flag and %%d will be the specifier.

                   ffmpeg -i in.nut -use_localtime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8

           This example will produce the playlist, out.m3u8, and segment files:
           file-20160215-1455569023.ts, file-20160215-1455569024.ts, etc.  Note: On some
           systems/environments, the %s specifier is not available. See
             "strftime()" documentation.

                   ffmpeg -i in.nut -use_localtime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8

           This example will produce the playlist, out.m3u8, and segment files:
           file-20160215-0001.ts, file-20160215-0002.ts, etc.

       use_localtime_mkdir
           Used together with -use_localtime, it will create all subdirectories which is expanded
           in filename.

                   ffmpeg -i in.nut -use_localtime 1 -use_localtime_mkdir 1 -hls_segment_filename '%Y%m%d/file-%Y%m%d-%s.ts' out.m3u8

           This example will create a directory 201560215 (if it does not exist), and then
           produce the playlist, out.m3u8, and segment files:
           20160215/file-20160215-1455569023.ts, 20160215/file-20160215-1455569024.ts, etc.

                   ffmpeg -i in.nut -use_localtime 1 -use_localtime_mkdir 1 -hls_segment_filename '%Y/%m/%d/file-%Y%m%d-%s.ts' out.m3u8

           This example will create a directory hierarchy 2016/02/15 (if any of them do not
           exist), and then produce the playlist, out.m3u8, and segment files:
           2016/02/15/file-20160215-1455569023.ts, 2016/02/15/file-20160215-1455569024.ts, etc.

       hls_key_info_file key_info_file
           Use the information in key_info_file for segment encryption. The first line of
           key_info_file specifies the key URI written to the playlist. The key URL is used to
           access the encryption key during playback. The second line specifies the path to the
           key file used to obtain the key during the encryption process. The key file is read as
           a single packed array of 16 octets in binary format. The optional third line specifies
           the initialization vector (IV) as a hexadecimal string to be used instead of the
           segment sequence number (default) for encryption. Changes to key_info_file will result
           in segment encryption with the new key/IV and an entry in the playlist for the new key
           URI/IV.

           Key info file format:

                   <key URI>
                   <key file path>
                   <IV> (optional)

           Example key URIs:

                   http://server/file.key
                   /path/to/file.key
                   file.key

           Example key file paths:

                   file.key
                   /path/to/file.key

           Example IV:

                   0123456789ABCDEF0123456789ABCDEF

           Key info file example:

                   http://server/file.key
                   /path/to/file.key
                   0123456789ABCDEF0123456789ABCDEF

           Example shell script:

                   #!/bin/sh
                   BASE_URL=${1:-'.'}
                   openssl rand 16 > file.key
                   echo $BASE_URL/file.key > file.keyinfo
                   echo file.key >> file.keyinfo
                   echo $(openssl rand -hex 16) >> file.keyinfo
                   ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
                     -hls_key_info_file file.keyinfo out.m3u8

       hls_flags flags
           Possible values:

           single_file
               If this flag is set, the muxer will store all segments in a single MPEG-TS file,
               and will use byte ranges in the playlist. HLS playlists generated with this way
               will have the version number 4.  For example:

                       ffmpeg -i in.nut -hls_flags single_file out.m3u8

               Will produce the playlist, out.m3u8, and a single segment file, out.ts.

           delete_segments
               Segment files removed from the playlist are deleted after a period of time equal
               to the duration of the segment plus the duration of the playlist.

           append_list
               Append new segments into the end of old segment list, and remove the
               "#EXT-X-ENDLIST" from the old segment list.

           round_durations
               Round the duration info in the playlist file segment info to integer values,
               instead of using floating point.

           discont_start
               Add the "#EXT-X-DISCONTINUITY" tag to the playlist, before the first segment's
               information.

           omit_endlist
               Do not append the "EXT-X-ENDLIST" tag at the end of the playlist.

           split_by_time
               Allow segments to start on frames other than keyframes. This improves behavior on
               some players when the time between keyframes is inconsistent, but may make things
               worse on others, and can cause some oddities during seeking. This flag should be
               used with the "hls_time" option.

           program_date_time
               Generate "EXT-X-PROGRAM-DATE-TIME" tags.

           second_level_segment_index
               Makes it possible to use segment indexes as %%d in hls_segment_filename expression
               besides date/time values when use_localtime is on.  To get fixed width numbers
               with trailing zeroes, %%0xd format is available where x is the required width.

           second_level_segment_size
               Makes it possible to use segment sizes (counted in bytes) as %%s in
               hls_segment_filename expression besides date/time values when use_localtime is on.
               To get fixed width numbers with trailing zeroes, %%0xs format is available where x
               is the required width.

           second_level_segment_duration
               Makes it possible to use segment duration (calculated  in microseconds) as %%t in
               hls_segment_filename expression besides date/time values when use_localtime is on.
               To get fixed width numbers with trailing zeroes, %%0xt format is available where x
               is the required width.

                       ffmpeg -i sample.mpeg \
                          -f hls -hls_time 3 -hls_list_size 5 \
                          -hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
                          -use_localtime 1 -use_localtime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8

               This will produce segments like this:
               segment_20170102194334_0003_00122200_0000003000000.ts,
               segment_20170102194334_0004_00120072_0000003000000.ts etc.

           temp_file
               Write segment data to filename.tmp and rename to filename only once the segment is
               complete. A webserver serving up segments can be configured to reject requests to
               *.tmp to prevent access to in-progress segments before they have been added to the
               m3u8 playlist.

       hls_playlist_type event
           Emit "#EXT-X-PLAYLIST-TYPE:EVENT" in the m3u8 header. Forces hls_list_size to 0; the
           playlist can only be appended to.

       hls_playlist_type vod
           Emit "#EXT-X-PLAYLIST-TYPE:VOD" in the m3u8 header. Forces hls_list_size to 0; the
           playlist must not change.

       method
           Use the given HTTP method to create the hls files.

                   ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8

           This example will upload all the mpegts segment files to the HTTP server using the
           HTTP PUT method, and update the m3u8 files every "refresh" times using the same
           method.  Note that the HTTP server must support the given method for uploading files.

   ico
       ICO file muxer.

       Microsoft's icon file format (ICO) has some strict limitations that should be noted:

       ·   Size cannot exceed 256 pixels in any dimension

       ·   Only BMP and PNG images can be stored

       ·   If a BMP image is used, it must be one of the following pixel formats:

                   BMP Bit Depth      FFmpeg Pixel Format
                   1bit               pal8
                   4bit               pal8
                   8bit               pal8
                   16bit              rgb555le
                   24bit              bgr24
                   32bit              bgra

       ·   If a BMP image is used, it must use the BITMAPINFOHEADER DIB header

       ·   If a PNG image is used, it must use the rgba pixel format

   image2
       Image file muxer.

       The image file muxer writes video frames to image files.

       The output filenames are specified by a pattern, which can be used to produce sequentially
       numbered series of files.  The pattern may contain the string "%d" or "%0Nd", this string
       specifies the position of the characters representing a numbering in the filenames. If the
       form "%0Nd" is used, the string representing the number in each filename is 0-padded to N
       digits. The literal character '%' can be specified in the pattern with the string "%%".

       If the pattern contains "%d" or "%0Nd", the first filename of the file list specified will
       contain the number 1, all the following numbers will be sequential.

       The pattern may contain a suffix which is used to automatically determine the format of
       the image files to write.

       For example the pattern "img-%03d.bmp" will specify a sequence of filenames of the form
       img-001.bmp, img-002.bmp, ..., img-010.bmp, etc.  The pattern "img%%-%d.jpg" will specify
       a sequence of filenames of the form img%-1.jpg, img%-2.jpg, ..., img%-10.jpg, etc.

       Examples

       The following example shows how to use ffmpeg for creating a sequence of files
       img-001.jpeg, img-002.jpeg, ..., taking one image every second from the input video:

               ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'

       Note that with ffmpeg, if the format is not specified with the "-f" option and the output
       filename specifies an image file format, the image2 muxer is automatically selected, so
       the previous command can be written as:

               ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'

       Note also that the pattern must not necessarily contain "%d" or "%0Nd", for example to
       create a single image file img.jpeg from the start of the input video you can employ the
       command:

               ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg

       The strftime option allows you to expand the filename with date and time information.
       Check the documentation of the "strftime()" function for the syntax.

       For example to generate image files from the "strftime()" "%Y-%m-%d_%H-%M-%S" pattern, the
       following ffmpeg command can be used:

               ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"

       Options

       start_number
           Start the sequence from the specified number. Default value is 0.

       update
           If set to 1, the filename will always be interpreted as just a filename, not a
           pattern, and the corresponding file will be continuously overwritten with new images.
           Default value is 0.

       strftime
           If set to 1, expand the filename with date and time information from "strftime()".
           Default value is 0.

       The image muxer supports the .Y.U.V image file format. This format is special in that that
       each image frame consists of three files, for each of the YUV420P components. To read or
       write this image file format, specify the name of the '.Y' file. The muxer will
       automatically open the '.U' and '.V' files as required.

   matroska
       Matroska container muxer.

       This muxer implements the matroska and webm container specs.

       Metadata

       The recognized metadata settings in this muxer are:

       title
           Set title name provided to a single track.

       language
           Specify the language of the track in the Matroska languages form.

           The language can be either the 3 letters bibliographic ISO-639-2 (ISO 639-2/B) form
           (like "fre" for French), or a language code mixed with a country code for specialities
           in languages (like "fre-ca" for Canadian French).

       stereo_mode
           Set stereo 3D video layout of two views in a single video track.

           The following values are recognized:

           mono
               video is not stereo

           left_right
               Both views are arranged side by side, Left-eye view is on the left

           bottom_top
               Both views are arranged in top-bottom orientation, Left-eye view is at bottom

           top_bottom
               Both views are arranged in top-bottom orientation, Left-eye view is on top

           checkerboard_rl
               Each view is arranged in a checkerboard interleaved pattern, Left-eye view being
               first

           checkerboard_lr
               Each view is arranged in a checkerboard interleaved pattern, Right-eye view being
               first

           row_interleaved_rl
               Each view is constituted by a row based interleaving, Right-eye view is first row

           row_interleaved_lr
               Each view is constituted by a row based interleaving, Left-eye view is first row

           col_interleaved_rl
               Both views are arranged in a column based interleaving manner, Right-eye view is
               first column

           col_interleaved_lr
               Both views are arranged in a column based interleaving manner, Left-eye view is
               first column

           anaglyph_cyan_red
               All frames are in anaglyph format viewable through red-cyan filters

           right_left
               Both views are arranged side by side, Right-eye view is on the left

           anaglyph_green_magenta
               All frames are in anaglyph format viewable through green-magenta filters

           block_lr
               Both eyes laced in one Block, Left-eye view is first

           block_rl
               Both eyes laced in one Block, Right-eye view is first

       For example a 3D WebM clip can be created using the following command line:

               ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm

       Options

       This muxer supports the following options:

       reserve_index_space
           By default, this muxer writes the index for seeking (called cues in Matroska terms) at
           the end of the file, because it cannot know in advance how much space to leave for the
           index at the beginning of the file. However for some use cases -- e.g.  streaming
           where seeking is possible but slow -- it is useful to put the index at the beginning
           of the file.

           If this option is set to a non-zero value, the muxer will reserve a given amount of
           space in the file header and then try to write the cues there when the muxing
           finishes. If the available space does not suffice, muxing will fail. A safe size for
           most use cases should be about 50kB per hour of video.

           Note that cues are only written if the output is seekable and this option will have no
           effect if it is not.

   md5
       MD5 testing format.

       This is a variant of the hash muxer. Unlike that muxer, it defaults to using the MD5 hash
       function.

       Examples

       To compute the MD5 hash of the input converted to raw audio and video, and store it in the
       file out.md5:

               ffmpeg -i INPUT -f md5 out.md5

       You can print the MD5 to stdout with the command:

               ffmpeg -i INPUT -f md5 -

       See also the hash and framemd5 muxers.

   mov, mp4, ismv
       MOV/MP4/ISMV (Smooth Streaming) muxer.

       The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4 file has all the
       metadata about all packets stored in one location (written at the end of the file, it can
       be moved to the start for better playback by adding faststart to the movflags, or using
       the qt-faststart tool). A fragmented file consists of a number of fragments, where packets
       and metadata about these packets are stored together. Writing a fragmented file has the
       advantage that the file is decodable even if the writing is interrupted (while a normal
       MOV/MP4 is undecodable if it is not properly finished), and it requires less memory when
       writing very long files (since writing normal MOV/MP4 files stores info about every single
       packet in memory until the file is closed). The downside is that it is less compatible
       with other applications.

       Options

       Fragmentation is enabled by setting one of the AVOptions that define how to cut the file
       into fragments:

       -moov_size bytes
           Reserves space for the moov atom at the beginning of the file instead of placing the
           moov atom at the end. If the space reserved is insufficient, muxing will fail.

       -movflags frag_keyframe
           Start a new fragment at each video keyframe.

       -frag_duration duration
           Create fragments that are duration microseconds long.

       -frag_size size
           Create fragments that contain up to size bytes of payload data.

       -movflags frag_custom
           Allow the caller to manually choose when to cut fragments, by calling
           "av_write_frame(ctx, NULL)" to write a fragment with the packets written so far. (This
           is only useful with other applications integrating libavformat, not from ffmpeg.)

       -min_frag_duration duration
           Don't create fragments that are shorter than duration microseconds long.

       If more than one condition is specified, fragments are cut when one of the specified
       conditions is fulfilled. The exception to this is "-min_frag_duration", which has to be
       fulfilled for any of the other conditions to apply.

       Additionally, the way the output file is written can be adjusted through a few other
       options:

       -movflags empty_moov
           Write an initial moov atom directly at the start of the file, without describing any
           samples in it. Generally, an mdat/moov pair is written at the start of the file, as a
           normal MOV/MP4 file, containing only a short portion of the file. With this option
           set, there is no initial mdat atom, and the moov atom only describes the tracks but
           has a zero duration.

           This option is implicitly set when writing ismv (Smooth Streaming) files.

       -movflags separate_moof
           Write a separate moof (movie fragment) atom for each track. Normally, packets for all
           tracks are written in a moof atom (which is slightly more efficient), but with this
           option set, the muxer writes one moof/mdat pair for each track, making it easier to
           separate tracks.

           This option is implicitly set when writing ismv (Smooth Streaming) files.

       -movflags faststart
           Run a second pass moving the index (moov atom) to the beginning of the file.  This
           operation can take a while, and will not work in various situations such as fragmented
           output, thus it is not enabled by default.

       -movflags rtphint
           Add RTP hinting tracks to the output file.

       -movflags disable_chpl
           Disable Nero chapter markers (chpl atom).  Normally, both Nero chapters and a
           QuickTime chapter track are written to the file. With this option set, only the
           QuickTime chapter track will be written. Nero chapters can cause failures when the
           file is reprocessed with certain tagging programs, like mp3Tag 2.61a and iTunes 11.3,
           most likely other versions are affected as well.

       -movflags omit_tfhd_offset
           Do not write any absolute base_data_offset in tfhd atoms. This avoids tying fragments
           to absolute byte positions in the file/streams.

       -movflags default_base_moof
           Similarly to the omit_tfhd_offset, this flag avoids writing the absolute
           base_data_offset field in tfhd atoms, but does so by using the new default-base-is-
           moof flag instead. This flag is new from 14496-12:2012. This may make the fragments
           easier to parse in certain circumstances (avoiding basing track fragment location
           calculations on the implicit end of the previous track fragment).

       -write_tmcd
           Specify "on" to force writing a timecode track, "off" to disable it and "auto" to
           write a timecode track only for mov and mp4 output (default).

       Example

       Smooth Streaming content can be pushed in real time to a publishing point on IIS with this
       muxer. Example:

               ffmpeg -re <<normal input/transcoding options>> -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)

       Audible AAX

       Audible AAX files are encrypted M4B files, and they can be decrypted by specifying a 4
       byte activation secret.

               ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4

   mp3
       The MP3 muxer writes a raw MP3 stream with the following optional features:

       ·   An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and 2.4
           are supported, the "id3v2_version" private option controls which one is used (3 or 4).
           Setting "id3v2_version" to 0 disables the ID3v2 header completely.

           The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.  The
           pictures are supplied to the muxer in form of a video stream with a single packet.
           There can be any number of those streams, each will correspond to a single APIC frame.
           The stream metadata tags title and comment map to APIC description and picture type
           respectively. See <http://id3.org/id3v2.4.0-frames> for allowed picture types.

           Note that the APIC frames must be written at the beginning, so the muxer will buffer
           the audio frames until it gets all the pictures. It is therefore advised to provide
           the pictures as soon as possible to avoid excessive buffering.

       ·   A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by default,
           but will be written only if the output is seekable. The "write_xing" private option
           can be used to disable it.  The frame contains various information that may be useful
           to the decoder, like the audio duration or encoder delay.

       ·   A legacy ID3v1 tag at the end of the file (disabled by default). It may be enabled
           with the "write_id3v1" private option, but as its capabilities are very limited, its
           usage is not recommended.

       Examples:

       Write an mp3 with an ID3v2.3 header and an ID3v1 footer:

               ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3

       To attach a picture to an mp3 file select both the audio and the picture stream with
       "map":

               ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
               -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3

       Write a "clean" MP3 without any extra features:

               ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3

   mpegts
       MPEG transport stream muxer.

       This muxer implements ISO 13818-1 and part of ETSI EN 300 468.

       The recognized metadata settings in mpegts muxer are "service_provider" and
       "service_name". If they are not set the default for "service_provider" is FFmpeg and the
       default for "service_name" is Service01.

       Options

       The muxer options are:

       mpegts_transport_stream_id integer
           Set the transport_stream_id. This identifies a transponder in DVB.  Default is 0x0001.

       mpegts_original_network_id integer
           Set the original_network_id. This is unique identifier of a network in DVB. Its main
           use is in the unique identification of a service through the path Original_Network_ID,
           Transport_Stream_ID. Default is 0x0001.

       mpegts_service_id integer
           Set the service_id, also known as program in DVB. Default is 0x0001.

       mpegts_service_type integer
           Set the program service_type. Default is "digital_tv".  Accepts the following options:

           hex_value
               Any hexdecimal value between 0x01 to 0xff as defined in ETSI 300 468.

           digital_tv
               Digital TV service.

           digital_radio
               Digital Radio service.

           teletext
               Teletext service.

           advanced_codec_digital_radio
               Advanced Codec Digital Radio service.

           mpeg2_digital_hdtv
               MPEG2 Digital HDTV service.

           advanced_codec_digital_sdtv
               Advanced Codec Digital SDTV service.

           advanced_codec_digital_hdtv
               Advanced Codec Digital HDTV service.

       mpegts_pmt_start_pid integer
           Set the first PID for PMT. Default is 0x1000. Max is 0x1f00.

       mpegts_start_pid integer
           Set the first PID for data packets. Default is 0x0100. Max is 0x0f00.

       mpegts_m2ts_mode boolean
           Enable m2ts mode if set to 1. Default value is "-1" which disables m2ts mode.

       muxrate integer
           Set a constant muxrate. Default is VBR.

       pes_payload_size integer
           Set minimum PES packet payload in bytes. Default is 2930.

       mpegts_flags flags
           Set mpegts flags. Accepts the following options:

           resend_headers
               Reemit PAT/PMT before writing the next packet.

           latm
               Use LATM packetization for AAC.

           pat_pmt_at_frames
               Reemit PAT and PMT at each video frame.

           system_b
               Conform to System B (DVB) instead of System A (ATSC).

           initial_discontinuity
               Mark the initial packet of each stream as discontinuity.

       resend_headers integer
           Reemit PAT/PMT before writing the next packet. This option is deprecated: use
           mpegts_flags instead.

       mpegts_copyts boolean
           Preserve original timestamps, if value is set to 1. Default value is "-1", which
           results in shifting timestamps so that they start from 0.

       omit_video_pes_length boolean
           Omit the PES packet length for video packets. Default is 1 (true).

       pcr_period integer
           Override the default PCR retransmission time in milliseconds. Ignored if variable
           muxrate is selected. Default is 20.

       pat_period double
           Maximum time in seconds between PAT/PMT tables.

       sdt_period double
           Maximum time in seconds between SDT tables.

       tables_version integer
           Set PAT, PMT and SDT version (default 0, valid values are from 0 to 31, inclusively).
           This option allows updating stream structure so that standard consumer may detect the
           change. To do so, reopen output "AVFormatContext" (in case of API usage) or restart
           ffmpeg instance, cyclically changing tables_version value:

                   ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
                   ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
                   ...
                   ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
                   ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
                   ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
                   ...

       Example

               ffmpeg -i file.mpg -c copy \
                    -mpegts_original_network_id 0x1122 \
                    -mpegts_transport_stream_id 0x3344 \
                    -mpegts_service_id 0x5566 \
                    -mpegts_pmt_start_pid 0x1500 \
                    -mpegts_start_pid 0x150 \
                    -metadata service_provider="Some provider" \
                    -metadata service_name="Some Channel" \
                    out.ts

   mxf, mxf_d10
       MXF muxer.

       Options

       The muxer options are:

       store_user_comments bool
           Set if user comments should be stored if available or never.  IRT D-10 does not allow
           user comments. The default is thus to write them for mxf but not for mxf_d10

   null
       Null muxer.

       This muxer does not generate any output file, it is mainly useful for testing or
       benchmarking purposes.

       For example to benchmark decoding with ffmpeg you can use the command:

               ffmpeg -benchmark -i INPUT -f null out.null

       Note that the above command does not read or write the out.null file, but specifying the
       output file is required by the ffmpeg syntax.

       Alternatively you can write the command as:

               ffmpeg -benchmark -i INPUT -f null -

   nut
       -syncpoints flags
           Change the syncpoint usage in nut:

           default use the normal low-overhead seeking aids.
           none do not use the syncpoints at all, reducing the overhead but making the stream
           non-seekable;
                   Use of this option is not recommended, as the resulting files are very damage
                   sensitive and seeking is not possible. Also in general the overhead from
                   syncpoints is negligible. Note, -C<write_index> 0 can be used to disable
                   all growing data tables, allowing to mux endless streams with limited memory
                   and without these disadvantages.

           timestamped extend the syncpoint with a wallclock field.

           The none and timestamped flags are experimental.

       -write_index bool
           Write index at the end, the default is to write an index.

               ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor

   ogg
       Ogg container muxer.

       -page_duration duration
           Preferred page duration, in microseconds. The muxer will attempt to create pages that
           are approximately duration microseconds long. This allows the user to compromise
           between seek granularity and container overhead. The default is 1 second. A value of 0
           will fill all segments, making pages as large as possible. A value of 1 will
           effectively use 1 packet-per-page in most situations, giving a small seek granularity
           at the cost of additional container overhead.

       -serial_offset value
           Serial value from which to set the streams serial number.  Setting it to different and
           sufficiently large values ensures that the produced ogg files can be safely chained.

   segment, stream_segment, ssegment
       Basic stream segmenter.

       This muxer outputs streams to a number of separate files of nearly fixed duration. Output
       filename pattern can be set in a fashion similar to image2, or by using a "strftime"
       template if the strftime option is enabled.

       "stream_segment" is a variant of the muxer used to write to streaming output formats, i.e.
       which do not require global headers, and is recommended for outputting e.g. to MPEG
       transport stream segments.  "ssegment" is a shorter alias for "stream_segment".

       Every segment starts with a keyframe of the selected reference stream, which is set
       through the reference_stream option.

       Note that if you want accurate splitting for a video file, you need to make the input key
       frames correspond to the exact splitting times expected by the segmenter, or the segment
       muxer will start the new segment with the key frame found next after the specified start
       time.

       The segment muxer works best with a single constant frame rate video.

       Optionally it can generate a list of the created segments, by setting the option
       segment_list. The list type is specified by the segment_list_type option. The entry
       filenames in the segment list are set by default to the basename of the corresponding
       segment files.

       See also the hls muxer, which provides a more specific implementation for HLS
       segmentation.

       Options

       The segment muxer supports the following options:

       increment_tc 1|0
           if set to 1, increment timecode between each segment If this is selected, the input
           need to have a timecode in the first video stream. Default value is 0.

       reference_stream specifier
           Set the reference stream, as specified by the string specifier.  If specifier is set
           to "auto", the reference is chosen automatically. Otherwise it must be a stream
           specifier (see the ``Stream specifiers'' chapter in the ffmpeg manual) which specifies
           the reference stream. The default value is "auto".

       segment_format format
           Override the inner container format, by default it is guessed by the filename
           extension.

       segment_format_options options_list
           Set output format options using a :-separated list of key=value parameters. Values
           containing the ":" special character must be escaped.

       segment_list name
           Generate also a listfile named name. If not specified no listfile is generated.

       segment_list_flags flags
           Set flags affecting the segment list generation.

           It currently supports the following flags:

           cache
               Allow caching (only affects M3U8 list files).

           live
               Allow live-friendly file generation.

       segment_list_size size
           Update the list file so that it contains at most size segments. If 0 the list file
           will contain all the segments. Default value is 0.

       segment_list_entry_prefix prefix
           Prepend prefix to each entry. Useful to generate absolute paths.  By default no prefix
           is applied.

       segment_list_type type
           Select the listing format.

           The following values are recognized:

           flat
               Generate a flat list for the created segments, one segment per line.

           csv, ext
               Generate a list for the created segments, one segment per line, each line matching
               the format (comma-separated values):

                       <segment_filename>,<segment_start_time>,<segment_end_time>

               segment_filename is the name of the output file generated by the muxer according
               to the provided pattern. CSV escaping (according to RFC4180) is applied if
               required.

               segment_start_time and segment_end_time specify the segment start and end time
               expressed in seconds.

               A list file with the suffix ".csv" or ".ext" will auto-select this format.

               ext is deprecated in favor or csv.

           ffconcat
               Generate an ffconcat file for the created segments. The resulting file can be read
               using the FFmpeg concat demuxer.

               A list file with the suffix ".ffcat" or ".ffconcat" will auto-select this format.

           m3u8
               Generate an extended M3U8 file, version 3, compliant with
               <http://tools.ietf.org/id/draft-pantos-http-live-streaming>.

               A list file with the suffix ".m3u8" will auto-select this format.

           If not specified the type is guessed from the list file name suffix.

       segment_time time
           Set segment duration to time, the value must be a duration specification. Default
           value is "2". See also the segment_times option.

           Note that splitting may not be accurate, unless you force the reference stream key-
           frames at the given time. See the introductory notice and the examples below.

       segment_atclocktime 1|0
           If set to "1" split at regular clock time intervals starting from 00:00 o'clock. The
           time value specified in segment_time is used for setting the length of the splitting
           interval.

           For example with segment_time set to "900" this makes it possible to create files at
           12:00 o'clock, 12:15, 12:30, etc.

           Default value is "0".

       segment_clocktime_offset duration
           Delay the segment splitting times with the specified duration when using
           segment_atclocktime.

           For example with segment_time set to "900" and segment_clocktime_offset set to "300"
           this makes it possible to create files at 12:05, 12:20, 12:35, etc.

           Default value is "0".

       segment_clocktime_wrap_duration duration
           Force the segmenter to only start a new segment if a packet reaches the muxer within
           the specified duration after the segmenting clock time. This way you can make the
           segmenter more resilient to backward local time jumps, such as leap seconds or
           transition to standard time from daylight savings time.

           Default is the maximum possible duration which means starting a new segment regardless
           of the elapsed time since the last clock time.

       segment_time_delta delta
           Specify the accuracy time when selecting the start time for a segment, expressed as a
           duration specification. Default value is "0".

           When delta is specified a key-frame will start a new segment if its PTS satisfies the
           relation:

                   PTS >= start_time - time_delta

           This option is useful when splitting video content, which is always split at GOP
           boundaries, in case a key frame is found just before the specified split time.

           In particular may be used in combination with the ffmpeg option force_key_frames. The
           key frame times specified by force_key_frames may not be set accurately because of
           rounding issues, with the consequence that a key frame time may result set just before
           the specified time. For constant frame rate videos a value of 1/(2*frame_rate) should
           address the worst case mismatch between the specified time and the time set by
           force_key_frames.

       segment_times times
           Specify a list of split points. times contains a list of comma separated duration
           specifications, in increasing order. See also the segment_time option.

       segment_frames frames
           Specify a list of split video frame numbers. frames contains a list of comma separated
           integer numbers, in increasing order.

           This option specifies to start a new segment whenever a reference stream key frame is
           found and the sequential number (starting from 0) of the frame is greater or equal to
           the next value in the list.

       segment_wrap limit
           Wrap around segment index once it reaches limit.

       segment_start_number number
           Set the sequence number of the first segment. Defaults to 0.

       strftime 1|0
           Use the "strftime" function to define the name of the new segments to write. If this
           is selected, the output segment name must contain a "strftime" function template.
           Default value is 0.

       break_non_keyframes 1|0
           If enabled, allow segments to start on frames other than keyframes. This improves
           behavior on some players when the time between keyframes is inconsistent, but may make
           things worse on others, and can cause some oddities during seeking. Defaults to 0.

       reset_timestamps 1|0
           Reset timestamps at the begin of each segment, so that each segment will start with
           near-zero timestamps. It is meant to ease the playback of the generated segments. May
           not work with some combinations of muxers/codecs. It is set to 0 by default.

       initial_offset offset
           Specify timestamp offset to apply to the output packet timestamps. The argument must
           be a time duration specification, and defaults to 0.

       write_empty_segments 1|0
           If enabled, write an empty segment if there are no packets during the period a segment
           would usually span. Otherwise, the segment will be filled with the next packet
           written. Defaults to 0.

       Examples

       ·   Remux the content of file in.mkv to a list of segments out-000.nut, out-001.nut, etc.,
           and write the list of generated segments to out.list:

                   ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.list out%03d.nut

       ·   Segment input and set output format options for the output segments:

                   ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4

       ·   Segment the input file according to the split points specified by the segment_times
           option:

                   ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 out%03d.nut

       ·   Use the ffmpeg force_key_frames option to force key frames in the input at the
           specified location, together with the segment option segment_time_delta to account for
           possible roundings operated when setting key frame times.

                   ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
                   -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut

           In order to force key frames on the input file, transcoding is required.

       ·   Segment the input file by splitting the input file according to the frame numbers
           sequence specified with the segment_frames option:

                   ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut

       ·   Convert the in.mkv to TS segments using the "libx264" and "aac" encoders:

                   ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts

       ·   Segment the input file, and create an M3U8 live playlist (can be used as live HLS
           source):

                   ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
                   -segment_list_flags +live -segment_time 10 out%03d.mkv

   smoothstreaming
       Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving
       with conventional web server.

       window_size
           Specify the number of fragments kept in the manifest. Default 0 (keep all).

       extra_window_size
           Specify the number of fragments kept outside of the manifest before removing from
           disk. Default 5.

       lookahead_count
           Specify the number of lookahead fragments. Default 2.

       min_frag_duration
           Specify the minimum fragment duration (in microseconds). Default 5000000.

       remove_at_exit
           Specify whether to remove all fragments when finished. Default 0 (do not remove).

   fifo
       The fifo pseudo-muxer allows the separation of encoding and muxing by using first-in-
       first-out queue and running the actual muxer in a separate thread. This is especially
       useful in combination with the tee muxer and can be used to send data to several
       destinations with different reliability/writing speed/latency.

       API users should be aware that callback functions (interrupt_callback, io_open and
       io_close) used within its AVFormatContext must be thread-safe.

       The behavior of the fifo muxer if the queue fills up or if the output fails is selectable,

       ·   output can be transparently restarted with configurable delay between retries based on
           real time or time of the processed stream.

       ·   encoding can be blocked during temporary failure, or continue transparently dropping
           packets in case fifo queue fills up.

       fifo_format
           Specify the format name. Useful if it cannot be guessed from the output name suffix.

       queue_size
           Specify size of the queue (number of packets). Default value is 60.

       format_opts
           Specify format options for the underlying muxer. Muxer options can be specified as a
           list of key=value pairs separated by ':'.

       drop_pkts_on_overflow bool
           If set to 1 (true), in case the fifo queue fills up, packets will be dropped rather
           than blocking the encoder. This makes it possible to continue streaming without
           delaying the input, at the cost of omitting part of the stream. By default this option
           is set to 0 (false), so in such cases the encoder will be blocked until the muxer
           processes some of the packets and none of them is lost.

       attempt_recovery bool
           If failure occurs, attempt to recover the output. This is especially useful when used
           with network output, since it makes it possible to restart streaming transparently.
           By default this option is set to 0 (false).

       max_recovery_attempts
           Sets maximum number of successive unsuccessful recovery attempts after which the
           output fails permanently. By default this option is set to 0 (unlimited).

       recovery_wait_time duration
           Waiting time before the next recovery attempt after previous unsuccessful recovery
           attempt. Default value is 5 seconds.

       recovery_wait_streamtime bool
           If set to 0 (false), the real time is used when waiting for the recovery attempt (i.e.
           the recovery will be attempted after at least recovery_wait_time seconds).  If set to
           1 (true), the time of the processed stream is taken into account instead (i.e. the
           recovery will be attempted after at least recovery_wait_time seconds of the stream is
           omitted).  By default, this option is set to 0 (false).

       recover_any_error bool
           If set to 1 (true), recovery will be attempted regardless of type of the error causing
           the failure. By default this option is set to 0 (false) and in case of certain
           (usually permanent) errors the recovery is not attempted even when attempt_recovery is
           set to 1.

       restart_with_keyframe bool
           Specify whether to wait for the keyframe after recovering from queue overflow or
           failure. This option is set to 0 (false) by default.

       Examples

       ·   Stream something to rtmp server, continue processing the stream at real-time rate even
           in case of temporary failure (network outage) and attempt to recover streaming every
           second indefinitely.

                   ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
                     -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name

   tee
       The tee muxer can be used to write the same data to several files or any other kind of
       muxer. It can be used, for example, to both stream a video to the network and save it to
       disk at the same time.

       It is different from specifying several outputs to the ffmpeg command-line tool because
       the audio and video data will be encoded only once with the tee muxer; encoding can be a
       very expensive process. It is not useful when using the libavformat API directly because
       it is then possible to feed the same packets to several muxers directly.

       use_fifo bool
           If set to 1, slave outputs will be processed in separate thread using fifo muxer. This
           allows to compensate for different speed/latency/reliability of outputs and setup
           transparent recovery. By default this feature is turned off.

       fifo_options
           Options to pass to fifo pseudo-muxer instances. See fifo.

       The slave outputs are specified in the file name given to the muxer, separated by '|'. If
       any of the slave name contains the '|' separator, leading or trailing spaces or any
       special character, it must be escaped (see the "Quoting and escaping" section in the
       ffmpeg-utils(1) manual).

       Muxer options can be specified for each slave by prepending them as a list of key=value
       pairs separated by ':', between square brackets. If the options values contain a special
       character or the ':' separator, they must be escaped; note that this is a second level
       escaping.

       The following special options are also recognized:

       f   Specify the format name. Useful if it cannot be guessed from the output name suffix.

       bsfs[/spec]
           Specify a list of bitstream filters to apply to the specified output.

       use_fifo bool
           This allows to override tee muxer use_fifo option for individual slave muxer.

       fifo_options
           This allows to override tee muxer fifo_options for individual slave muxer.  See fifo.

           It is possible to specify to which streams a given bitstream filter applies, by
           appending a stream specifier to the option separated by "/". spec must be a stream
           specifier (see Format stream specifiers).  If the stream specifier is not specified,
           the bitstream filters will be applied to all streams in the output.

           Several bitstream filters can be specified, separated by ",".

       select
           Select the streams that should be mapped to the slave output, specified by a stream
           specifier. If not specified, this defaults to all the input streams. You may use
           multiple stream specifiers separated by commas (",") e.g.: "a:0,v"

       onfail
           Specify behaviour on output failure. This can be set to either "abort" (which is
           default) or "ignore". "abort" will cause whole process to fail in case of failure on
           this slave output. "ignore" will ignore failure on this output, so other outputs will
           continue without being affected.

       Examples

       ·   Encode something and both archive it in a WebM file and stream it as MPEG-TS over UDP
           (the streams need to be explicitly mapped):

                   ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
                     "archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"

       ·   As above, but continue streaming even if output to local file fails (for example local
           drive fills up):

                   ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
                     "[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"

       ·   Use ffmpeg to encode the input, and send the output to three different destinations.
           The "dump_extra" bitstream filter is used to add extradata information to all the
           output video keyframes packets, as requested by the MPEG-TS format. The select option
           is applied to out.aac in order to make it contain only audio packets.

                   ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
                          -f tee "[bsfs/v=dump_extra]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"

       ·   As below, but select only stream "a:1" for the audio output. Note that a second level
           escaping must be performed, as ":" is a special character used to separate options.

                   ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
                          -f tee "[bsfs/v=dump_extra]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"

       Note: some codecs may need different options depending on the output format; the auto-
       detection of this can not work with the tee muxer. The main example is the global_header
       flag.

   webm_dash_manifest
       WebM DASH Manifest muxer.

       This muxer implements the WebM DASH Manifest specification to generate the DASH manifest
       XML. It also supports manifest generation for DASH live streams.

       For more information see:

       ·   WebM DASH Specification:
           <https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification>

       ·   ISO DASH Specification:
           <http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip>

       Options

       This muxer supports the following options:

       adaptation_sets
           This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x
           and y are the unique identifiers of the adaptation sets and a,b,c,d and e are the
           indices of the corresponding audio and video streams. Any number of adaptation sets
           can be added using this option.

       live
           Set this to 1 to create a live stream DASH Manifest. Default: 0.

       chunk_start_index
           Start index of the first chunk. This will go in the startNumber attribute of the
           SegmentTemplate element in the manifest. Default: 0.

       chunk_duration_ms
           Duration of each chunk in milliseconds. This will go in the duration attribute of the
           SegmentTemplate element in the manifest. Default: 1000.

       utc_timing_url
           URL of the page that will return the UTC timestamp in ISO format. This will go in the
           value attribute of the UTCTiming element in the manifest.  Default: None.

       time_shift_buffer_depth
           Smallest time (in seconds) shifting buffer for which any Representation is guaranteed
           to be available. This will go in the timeShiftBufferDepth attribute of the MPD
           element. Default: 60.

       minimum_update_period
           Minimum update period (in seconds) of the manifest. This will go in the
           minimumUpdatePeriod attribute of the MPD element. Default: 0.

       Example

               ffmpeg -f webm_dash_manifest -i video1.webm \
                      -f webm_dash_manifest -i video2.webm \
                      -f webm_dash_manifest -i audio1.webm \
                      -f webm_dash_manifest -i audio2.webm \
                      -map 0 -map 1 -map 2 -map 3 \
                      -c copy \
                      -f webm_dash_manifest \
                      -adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
                      manifest.xml

   webm_chunk
       WebM Live Chunk Muxer.

       This muxer writes out WebM headers and chunks as separate files which can be consumed by
       clients that support WebM Live streams via DASH.

       Options

       This muxer supports the following options:

       chunk_start_index
           Index of the first chunk (defaults to 0).

       header
           Filename of the header where the initialization data will be written.

       audio_chunk_duration
           Duration of each audio chunk in milliseconds (defaults to 5000).

       Example

               ffmpeg -f v4l2 -i /dev/video0 \
                      -f alsa -i hw:0 \
                      -map 0:0 \
                      -c:v libvpx-vp9 \
                      -s 640x360 -keyint_min 30 -g 30 \
                      -f webm_chunk \
                      -header webm_live_video_360.hdr \
                      -chunk_start_index 1 \
                      webm_live_video_360_%d.chk \
                      -map 1:0 \
                      -c:a libvorbis \
                      -b:a 128k \
                      -f webm_chunk \
                      -header webm_live_audio_128.hdr \
                      -chunk_start_index 1 \
                      -audio_chunk_duration 1000 \
                      webm_live_audio_128_%d.chk

METADATA

       FFmpeg is able to dump metadata from media files into a simple UTF-8-encoded INI-like text
       file and then load it back using the metadata muxer/demuxer.

       The file format is as follows:

       1.  A file consists of a header and a number of metadata tags divided into sections, each
           on its own line.

       2.  The header is a ;FFMETADATA string, followed by a version number (now 1).

       3.  Metadata tags are of the form key=value

       4.  Immediately after header follows global metadata

       5.  After global metadata there may be sections with per-stream/per-chapter metadata.

       6.  A section starts with the section name in uppercase (i.e. STREAM or CHAPTER) in
           brackets ([, ]) and ends with next section or end of file.

       7.  At the beginning of a chapter section there may be an optional timebase to be used for
           start/end values. It must be in form TIMEBASE=num/den, where num and den are integers.
           If the timebase is missing then start/end times are assumed to be in milliseconds.

           Next a chapter section must contain chapter start and end times in form START=num,
           END=num, where num is a positive integer.

       8.  Empty lines and lines starting with ; or # are ignored.

       9.  Metadata keys or values containing special characters (=, ;, #, \ and a newline) must
           be escaped with a backslash \.

       10. Note that whitespace in metadata (e.g. foo = bar) is considered to be a part of the
           tag (in the example above key is foo , value is
            bar).

       A ffmetadata file might look like this:

               ;FFMETADATA1
               title=bike\\shed
               ;this is a comment
               artist=FFmpeg troll team

               [CHAPTER]
               TIMEBASE=1/1000
               START=0
               #chapter ends at 0:01:00
               END=60000
               title=chapter \#1
               [STREAM]
               title=multi\
               line

       By using the ffmetadata muxer and demuxer it is possible to extract metadata from an input
       file to an ffmetadata file, and then transcode the file into an output file with the
       edited ffmetadata file.

       Extracting an ffmetadata file with ffmpeg goes as follows:

               ffmpeg -i INPUT -f ffmetadata FFMETADATAFILE

       Reinserting edited metadata information from the FFMETADATAFILE file can be done as:

               ffmpeg -i INPUT -i FFMETADATAFILE -map_metadata 1 -codec copy OUTPUT

SEE ALSO

       ffmpeg(1), ffplay(1), ffprobe(1), ffserver(1), libavformat(3)

AUTHORS

       The FFmpeg developers.

       For details about the authorship, see the Git history of the project
       (git://source.ffmpeg.org/ffmpeg), e.g. by typing the command git log in the FFmpeg source
       directory, or browsing the online repository at <http://source.ffmpeg.org>.

       Maintainers for the specific components are listed in the file MAINTAINERS in the source
       code tree.

                                                                                FFMPEG-FORMATS(1)