diff --git "a/ffmpeg/doc/ffmpeg-formats.html" "b/ffmpeg/doc/ffmpeg-formats.html" deleted file mode 100644--- "a/ffmpeg/doc/ffmpeg-formats.html" +++ /dev/null @@ -1,6872 +0,0 @@ - - - - - - - FFmpeg Formats Documentation - - - - - - -
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- FFmpeg Formats Documentation -

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Table of Contents

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1 Description

- -

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

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-
-

2 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. -

-
-
max_probe_packets integer (input)
-

Set the maximum number of buffered packets when probing a codec. -Default is 2500 packets. -

-
-
packetsize integer (output)
-

Set packet size. -

-
-
fflags flags
-

Set format flags. Some are implemented for a limited number of formats. -

-

Possible values for input files: -

-
‘discardcorrupt’
-

Discard corrupted packets. -

-
‘fastseek’
-

Enable fast, but inaccurate seeks for some formats. -

-
‘genpts’
-

Generate missing PTS if DTS is present. -

-
‘igndts’
-

Ignore DTS if PTS is also set. In case the PTS is set, the DTS value -is set to NOPTS. This is ignored when the nofillin flag is set. -

-
‘ignidx’
-

Ignore index. -

-
‘nobuffer’
-

Reduce the latency introduced by buffering during initial input streams analysis. -

-
‘nofillin’
-

Do not fill in missing values in packet fields that can be exactly calculated. -

-
‘noparse’
-

Disable AVParsers, this needs +nofillin too. -

-
‘sortdts’
-

Try to interleave output packets by DTS. At present, available only for AVIs with an index. -

-
- -

Possible values for output files: -

-
‘autobsf’
-

Automatically apply bitstream filters as required by the output format. Enabled by default. -

-
‘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. -

-
‘flush_packets’
-

Write out packets immediately. -

-
‘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. -

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‘buffer’
-

Detect improper bitstream length. -

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‘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. -

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‘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 10000000 (10 seconds). -

-

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 is -1 (auto), which -means that the underlying protocol will decide, 1 enables it, and has the -effect of reducing the latency, 0 disables it and may increase IO throughput 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 indentation: -

-
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. -

-
-
skip_estimate_duration_from_pts bool (input)
-

Skip estimation of input duration if it requires an additional probing for PTS at end of file. -At present, applicable for MPEG-PS and MPEG-TS. -

-
-
duration_probesize integer (input)
-

Set probing size, in bytes, for input duration estimation when it actually requires -an additional probing for PTS at end of file (at present: MPEG-PS and MPEG-TS). -It is aimed at users interested in better durations probing for itself, or indirectly -because using the concat demuxer, for example. -The typical use case is an MPEG-TS CBR with a high bitrate, high video buffering and -ending cleaning with similar PTS for video and audio: in such a scenario, the large -physical gap between the last video packet and the last audio packet makes it necessary -to read many bytes in order to get the video stream duration. -Another use case is where the default probing behaviour only reaches a single video frame which is -not the last one of the stream due to frame reordering, so the duration is not accurate. -Setting this option has a performance impact even for small files because the probing -size is fixed. -Default behaviour is a general purpose trade-off, largely adaptive, but the probing size -will not be extended to get streams durations at all costs. -Must be an integer not lesser than 1, or 0 for default behaviour. -

-
-
strict, f_strict integer (input/output)
-

Specify how strictly to follow the standards. f_strict is deprecated and -should be used only via the ffmpeg tool. -

-

Possible values: -

-
‘very’
-

strictly conform to an older more strict version of the spec or reference software -

-
‘strict’
-

strictly conform to all the things in the spec no matter what consequences -

-
‘normal’
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‘unofficial’
-

allow unofficial extensions -

-
‘experimental’
-

allow non standardized experimental things, experimental -(unfinished/work in progress/not well tested) decoders and encoders. -Note: experimental decoders can pose a security risk, do not use this for -decoding untrusted input. -

-
- -
-
- - - -
-

2.1 Format stream specifiers

- -

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

-

The exact semantics of stream specifiers is defined by the -avformat_match_stream_specifier() function declared in the -libavformat/avformat.h header and documented in the -Stream specifiers section in the ffmpeg(1) manual. -

-
-
-
-

3 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. -

- -
-

3.1 aa

- -

Audible Format 2, 3, and 4 demuxer. -

-

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

-
-
-

3.2 aac

- -

Raw Audio Data Transport Stream AAC demuxer. -

-

This demuxer is used to demux an ADTS input containing a single AAC stream -alongwith any ID3v1/2 or APE tags in it. -

-
-
-

3.3 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. Default is enabled. -

-
-
-max_fps int
-

Maximum framerate in frames per second. Default of 0 imposes no limit. -

-
-
-default_fps int
-

Default framerate in frames per second when none is specified in the file -(0 meaning as fast as possible). Default is 15. -

-
-
- -
-
-

3.4 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. -

-
- -
-
-

3.5 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. -

- -
-

3.5.1 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. -

-

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. -This directive is deprecated, use file_packet_meta instead. -

-
-
file_packet_meta 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. -

-
-
option key value
-

Option to access, open and probe the file. -Can be present multiple times. -

-
-
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. -

-
-
stream_meta key value
-

Metadata for the stream. -Can be present multiple times. -

-
-
stream_codec value
-

Codec for the stream. -

-
-
stream_extradata hex_string
-

Extradata for the string, encoded in hexadecimal. -

-
-
chapter id start end
-

Add a chapter. id is an unique identifier, possibly small and -consecutive. -

-
-
- -
-
-

3.5.2 Options

- -

This demuxer accepts the following option: -

-
-
safe
-

If set to 1, reject unsafe file paths and directives. -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. -

-
-
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. -

-
-
- -
-
-

3.5.3 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
-
    -
- -
-
-
-

3.6 dash

- -

Dynamic Adaptive Streaming over HTTP demuxer. -

-

This demuxer presents all AVStreams found in the manifest. -By setting the discard flags on AVStreams the caller can decide -which streams to actually receive. -Each stream mirrors the id and bandwidth properties from the -<Representation> as metadata keys named "id" and "variant_bitrate" respectively. -

- -
-

3.6.1 Options

- -

This demuxer accepts the following option: -

-
-
cenc_decryption_key
-

16-byte key, in hex, to decrypt files encrypted using ISO Common Encryption (CENC/AES-128 CTR; ISO/IEC 23001-7). -

-
-
- -
-
-
-

3.7 dvdvideo

- -

DVD-Video demuxer, powered by libdvdnav and libdvdread. -

-

Can directly ingest DVD titles, specifically sequential PGCs, into -a conversion pipeline. Menu assets, such as background video or audio, -can also be demuxed given the menu’s coordinates (at best effort). -Seeking is not supported at this time. -

-

Block devices (DVD drives), ISO files, and directory structures are accepted. -Activate with -f dvdvideo in front of one of these inputs. -

-

This demuxer does NOT have decryption code of any kind. You are on your own -working with encrypted DVDs, and should not expect support on the matter. -

-

Underlying playback is handled by libdvdnav, and structure parsing by libdvdread. -FFmpeg must be built with GPL library support available as well as the -configure switches --enable-libdvdnav and --enable-libdvdread. -

-

You will need to provide either the desired "title number" or exact PGC/PG coordinates. -Many open-source DVD players and tools can aid in providing this information. -If not specified, the demuxer will default to title 1 which works for many discs. -However, due to the flexibility of the format, it is recommended to check manually. -There are many discs that are authored strangely or with invalid headers. -

-

If the input is a real DVD drive, please note that there are some drives which may -silently fail on reading bad sectors from the disc, returning random bits instead -which is effectively corrupt data. This is especially prominent on aging or rotting discs. -A second pass and integrity checks would be needed to detect the corruption. -This is not an FFmpeg issue. -

- -
-

3.7.1 Background

- -

DVD-Video is not a directly accessible, linear container format in the -traditional sense. Instead, it allows for complex and programmatic playback of -carefully muxed MPEG-PS streams that are stored in headerless VOB files. -To the end-user, these streams are known simply as "titles", but the actual -logical playback sequence is defined by one or more "PGCs", or Program Group Chains, -within the title. The PGC is in turn comprised of multiple "PGs", or Programs", -which are the actual video segments (and for a typical video feature, sequentially -ordered). The PGC structure, along with stream layout and metadata, are stored in -IFO files that need to be parsed. PGCs can be thought of as playlists in easier terms. -

-

An actual DVD player relies on user GUI interaction via menus and an internal VM -to drive the direction of demuxing. Generally, the user would either navigate (via menus) -or automatically be redirected to the PGC of their choice. During this process and -the subsequent playback, the DVD player’s internal VM also maintains a state and -executes instructions that can create jumps to different sectors during playback. -This is why libdvdnav is involved, as a linear read of the MPEG-PS blobs on the -disc (VOBs) is not enough to produce the right sequence in many cases. -

-

There are many other DVD structures (a long subject) that will not be discussed here. -NAV packets, in particular, are handled by this demuxer to build accurate timing -but not emitted as a stream. For a good high-level understanding, refer to: -https://code.videolan.org/videolan/libdvdnav/-/blob/master/doc/dvd_structures -

-
-
-

3.7.2 Options

- -

This demuxer accepts the following options: -

-
-
title int
-

The title number to play. Must be set if pgc and pg are not set. -Not applicable to menus. -Default is 0 (auto), which currently only selects the first available title (title 1) -and notifies the user about the implications. -

-
-
chapter_start int
-

The chapter, or PTT (part-of-title), number to start at. Not applicable to menus. -Default is 1. -

-
-
chapter_end int
-

The chapter, or PTT (part-of-title), number to end at. Not applicable to menus. -Default is 0, which is a special value to signal end at the last possible chapter. -

-
-
angle int
-

The video angle number, referring to what is essentially an additional -video stream that is composed from alternate frames interleaved in the VOBs. -Not applicable to menus. -Default is 1. -

-
-
region int
-

The region code to use for playback. Some discs may use this to default playback -at a particular angle in different regions. This option will not affect the region code -of a real DVD drive, if used as an input. Not applicable to menus. -Default is 0, "world". -

-
-
menu bool
-

Demux menu assets instead of navigating a title. Requires exact coordinates -of the menu (menu_lu, menu_vts, pgc, pg). -Default is false. -

-
-
menu_lu int
-

The menu language to demux. In DVD, menus are grouped by language. -Default is 1, the first language unit. -

-
-
menu_vts int
-

The VTS where the menu lives, or 0 if it is a VMG menu (root-level). -Default is 1, menu of the first VTS. -

-
-
pgc int
-

The entry PGC to start playback, in conjunction with pg. -Alternative to setting title. -Chapter markers are not supported at this time. -Must be explicitly set for menus. -Default is 0, automatically resolve from value of title. -

-
-
pg int
-

The entry PG to start playback, in conjunction with pgc. -Alternative to setting title. -Chapter markers are not supported at this time. -Default is 1, the first PG of the PGC. -

-
-
preindex bool
-

Enable this to have accurate chapter (PTT) markers and duration measurement, -which requires a slow second pass read in order to index the chapter marker -timestamps from NAV packets. This is non-ideal extra work for real optical drives. -It is recommended and faster to use this option with a backup of the DVD structure -stored on a hard drive. Not compatible with pgc and pg. -Default is 0, false. -

-
-
trim bool
-

Skip padding cells (i.e. cells shorter than 1 second) from the beginning. -There exist many discs with filler segments at the beginning of the PGC, -often with junk data intended for controlling a real DVD player’s -buffering speed and with no other material data value. -Not applicable to menus. -Default is 1, true. -

-
-
- -
-
-

3.7.3 Examples

- -
    -
  • Open title 3 from a given DVD structure: -
    -
    ffmpeg -f dvdvideo -title 3 -i <path to DVD> ...
-
    - -
  • Open chapters 3-6 from title 1 from a given DVD structure: -
    -
    ffmpeg -f dvdvideo -chapter_start 3 -chapter_end 6 -title 1 -i <path to DVD> ...
-
    - -
  • Open only chapter 5 from title 1 from a given DVD structure: -
    -
    ffmpeg -f dvdvideo -chapter_start 5 -chapter_end 5 -title 1 -i <path to DVD> ...
-
    - -
  • Demux menu with language 1 from VTS 1, PGC 1, starting at PG 1: -
    -
    ffmpeg -f dvdvideo -menu 1 -menu_lu 1 -menu_vts 1 -pgc 1 -pg 1 -i <path to DVD> ...
-
    -
- -
-
-
-

3.8 ea

- -

Electronic Arts Multimedia format demuxer. -

-

This format is used by various Electronic Arts games. -

- -
-

3.8.1 Options

- -
-
merge_alpha bool
-
-

Normally the VP6 alpha channel (if exists) is returned as a secondary video -stream, by setting this option you can make the demuxer return a single video -stream which contains the alpha channel in addition to the ordinary video. -

-
-
- -
-
-
-

3.9 imf

- -

Interoperable Master Format demuxer. -

-

This demuxer presents audio and video streams found in an IMF Composition, as -specified in SMPTE ST 2067-2. -

-
-
ffmpeg [-assetmaps <path of ASSETMAP1>,<path of ASSETMAP2>,...] -i <path of CPL> ...
-
- -

If -assetmaps is not specified, the demuxer looks for a file called -ASSETMAP.xml in the same directory as the CPL. -

-
-
-

3.10 flv, live_flv, kux

- -

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. -KUX is a flv variant used on the Youku platform. -

-
-
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. -

-
-
-flv_ignore_prevtag bool
-

Ignore the size of previous tag value. -

-
-
-flv_full_metadata bool
-

Output all context of the onMetadata. -

-
- -
-
-

3.11 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. -

-
-
-

3.12 hls

- -

HLS demuxer -

-

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". -

-

It accepts the following options: -

-
-
live_start_index
-

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

-
-
prefer_x_start
-

prefer to use #EXT-X-START if it’s in playlist instead of live_start_index. -

-
-
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. -

-
-
m3u8_hold_counters
-

The maximum number of times to load m3u8 when it refreshes without new segments. -Default value is 1000. -

-
-
http_persistent
-

Use persistent HTTP connections. Applicable only for HTTP streams. -Enabled by default. -

-
-
http_multiple
-

Use multiple HTTP connections for downloading HTTP segments. -Enabled by default for HTTP/1.1 servers. -

-
-
http_seekable
-

Use HTTP partial requests for downloading HTTP segments. -0 = disable, 1 = enable, -1 = auto, Default is auto. -

-
-
seg_format_options
-

Set options for the demuxer of media segments using a list of key=value pairs separated by :. -

-
-
seg_max_retry
-

Maximum number of times to reload a segment on error, useful when segment skip on network error is not desired. -Default value is 0. -

-
- -
-
-

3.13 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. -

-
export_path_metadata
-

If set to 1, will add two extra fields to the metadata found in input, making them -also available for other filters (see drawtext filter for examples). Default -value is 0. The extra fields are described below: -

-
lavf.image2dec.source_path
-

Corresponds to the full path to the input file being read. -

-
lavf.image2dec.source_basename
-

Corresponds to the name of the file being read. -

-
- -
-
- - -
-

3.13.1 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
-
    -
- -
-
-
-

3.14 libgme

- -

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

-

See https://bitbucket.org/mpyne/game-music-emu/overview for more information. -

-

It accepts the following options: -

-
-
track_index
-

Set the index of which track to demux. The demuxer can only export one track. -Track indexes start at 0. Default is to pick the first track. Number of tracks -is exported as tracks metadata entry. -

-
-
sample_rate
-

Set the sampling rate of the exported track. Range is 1000 to 999999. Default is 44100. -

-
-
max_size (bytes)
-

The demuxer buffers the entire file into memory. Adjust this value to set the maximum buffer size, -which in turn, acts as a ceiling for the size of files that can be read. -Default is 50 MiB. -

-
-
- -
-
-

3.15 libmodplug

- -

ModPlug based module demuxer -

-

See https://github.com/Konstanty/libmodplug -

-

It will export one 2-channel 16-bit 44.1 kHz audio stream. -Optionally, a pal8 16-color video stream can be exported with or without printed metadata. -

-

It accepts the following options: -

-
-
noise_reduction
-

Apply a simple low-pass filter. Can be 1 (on) or 0 (off). Default is 0. -

-
-
reverb_depth
-

Set amount of reverb. Range 0-100. Default is 0. -

-
-
reverb_delay
-

Set delay in ms, clamped to 40-250 ms. Default is 0. -

-
-
bass_amount
-

Apply bass expansion a.k.a. XBass or megabass. Range is 0 (quiet) to 100 (loud). Default is 0. -

-
-
bass_range
-

Set cutoff i.e. upper-bound for bass frequencies. Range is 10-100 Hz. Default is 0. -

-
-
surround_depth
-

Apply a Dolby Pro-Logic surround effect. Range is 0 (quiet) to 100 (heavy). Default is 0. -

-
-
surround_delay
-

Set surround delay in ms, clamped to 5-40 ms. Default is 0. -

-
-
max_size
-

The demuxer buffers the entire file into memory. Adjust this value to set the maximum buffer size, -which in turn, acts as a ceiling for the size of files that can be read. Range is 0 to 100 MiB. -0 removes buffer size limit (not recommended). Default is 5 MiB. -

-
-
video_stream_expr
-

String which is evaluated using the eval API to assign colors to the generated video stream. -Variables which can be used are x, y, w, h, t, speed, -tempo, order, pattern and row. -

-
-
video_stream
-

Generate video stream. Can be 1 (on) or 0 (off). Default is 0. -

-
-
video_stream_w
-

Set video frame width in ’chars’ where one char indicates 8 pixels. Range is 20-512. Default is 30. -

-
-
video_stream_h
-

Set video frame height in ’chars’ where one char indicates 8 pixels. Range is 20-512. Default is 30. -

-
-
video_stream_ptxt
-

Print metadata on video stream. Includes speed, tempo, order, pattern, -row and ts (time in ms). Can be 1 (on) or 0 (off). Default is 1. -

-
-
- -
-
-

3.16 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. -

-
- -
-
-

3.17 mov/mp4/3gp

- -

Demuxer for Quicktime File Format & ISO/IEC Base Media File Format (ISO/IEC 14496-12 or MPEG-4 Part 12, ISO/IEC 15444-12 or JPEG 2000 Part 12). -

-

Registered extensions: mov, mp4, m4a, 3gp, 3g2, mj2, psp, m4b, ism, ismv, isma, f4v -

- -
-

3.17.1 Options

- -

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. -

-
-
seek_streams_individually
-

When seeking, identify the closest point in each stream individually and demux packets in -that stream from identified point. This can lead to a different sequence of packets compared -to demuxing linearly from the beginning. Default is true. -

-
-
ignore_editlist
-

Ignore any edit list atoms. The demuxer, by default, modifies the stream index to reflect the -timeline described by the edit list. Default is false. -

-
-
advanced_editlist
-

Modify the stream index to reflect the timeline described by the edit list. ignore_editlist -must be set to false for this option to be effective. -If both ignore_editlist and this option are set to false, then only the -start of the stream index is modified to reflect initial dwell time or starting timestamp -described by the edit list. Default is true. -

-
-
ignore_chapters
-

Don’t parse chapters. This includes GoPro ’HiLight’ tags/moments. Note that chapters are -only parsed when input is seekable. Default is false. -

-
-
use_mfra_for
-

For seekable fragmented input, set fragment’s starting timestamp from media fragment random access box, if present. -

-

Following options are available: -

-
‘auto’
-

Auto-detect whether to set mfra timestamps as PTS or DTS (default) -

-
-
‘dts’
-

Set mfra timestamps as DTS -

-
-
‘pts’
-

Set mfra timestamps as PTS -

-
-
‘0’
-

Don’t use mfra box to set timestamps -

-
- -
-
use_tfdt
-

For fragmented input, set fragment’s starting timestamp to baseMediaDecodeTime from the tfdt box. -Default is enabled, which will prefer to use the tfdt box to set DTS. Disable to use the earliest_presentation_time from the sidx box. -In either case, the timestamp from the mfra box will be used if it’s available and use_mfra_for is -set to pts or dts. -

-
-
export_all
-

Export unrecognized boxes within the udta box as metadata entries. The first four -characters of the box type are set as the key. Default is false. -

-
-
export_xmp
-

Export entire contents of XMP_ box and uuid box as a string with key xmp. Note that -if export_all is set and this option isn’t, the contents of XMP_ box are still exported -but with key XMP_. Default is false. -

-
-
activation_bytes
-

4-byte key required to decrypt Audible AAX and AAX+ files. See Audible AAX subsection below. -

-
-
audible_fixed_key
-

Fixed key used for handling Audible AAX/AAX+ files. It has been pre-set so should not be necessary to -specify. -

-
-
decryption_key
-

16-byte key, in hex, to decrypt files encrypted using ISO Common Encryption (CENC/AES-128 CTR; ISO/IEC 23001-7). -

-
-
max_stts_delta
-

Very high sample deltas written in a trak’s stts box may occasionally be intended but usually they are written in -error or used to store a negative value for dts correction when treated as signed 32-bit integers. This option lets -the user set an upper limit, beyond which the delta is clamped to 1. Values greater than the limit if negative when -cast to int32 are used to adjust onward dts. -

-

Unit is the track time scale. Range is 0 to UINT_MAX. Default is UINT_MAX - 48000*10 which allows up to -a 10 second dts correction for 48 kHz audio streams while accommodating 99.9% of uint32 range. -

-
-
interleaved_read
-

Interleave packets from multiple tracks at demuxer level. For badly interleaved files, this prevents playback issues -caused by large gaps between packets in different tracks, as MOV/MP4 do not have packet placement requirements. -However, this can cause excessive seeking on very badly interleaved files, due to seeking between tracks, so disabling -it may prevent I/O issues, at the expense of playback. -

-
-
- -
-
-

3.17.2 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
-
- -
-
-
-

3.18 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. -

-
-
skip_unknown_pmt
-

Skip PMTs for programs not defined in the PAT. Default value is 0. -

-
-
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. -

-
-
merge_pmt_versions
-

Re-use existing streams when a PMT’s version is updated and elementary -streams move to different PIDs. Default value is 0. -

-
-
max_packet_size
-

Set maximum size, in bytes, of packet emitted by the demuxer. Payloads above this size -are split across multiple packets. Range is 1 to INT_MAX/2. Default is 204800 bytes. -

-
- -
-
-

3.19 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. -

-
- -
-
-

3.20 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
-
- -
-
-

3.21 rcwt

- -

RCWT (Raw Captions With Time) is a format native to ccextractor, a commonly -used open source tool for processing 608/708 Closed Captions (CC) sources. -For more information on the format, see (ffmpeg-formats)rcwtenc. -

-

This demuxer implements the specification as of March 2024, which has -been stable and unchanged since April 2014. -

- -
-

3.21.1 Examples

- -
    -
  • Render CC to ASS using the built-in decoder: -
    -
    ffmpeg -i CC.rcwt.bin CC.ass
-
    -

    Note that if your output appears to be empty, you may have to manually -set the decoder’s data_field option to pick the desired CC substream. -

    -
  • Convert an RCWT backup to Scenarist (SCC) format: -
    -
    ffmpeg -i CC.rcwt.bin -c:s copy CC.scc
-
    -

    Note that the SCC format does not support all of the possible CC extensions -that can be stored in RCWT (such as EIA-708). -

- -
-
-
-

3.22 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. -

-
-
-

3.23 tedcaptions

- -

JSON captions used for TED Talks. -

-

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
-
- -
-
-

3.24 vapoursynth

- -

Vapoursynth wrapper. -

-

Due to security concerns, Vapoursynth scripts will not -be autodetected so the input format has to be forced. For ff* CLI tools, -add -f vapoursynth before the input -i yourscript.vpy. -

-

This demuxer accepts the following option: -

-
max_script_size
-

The demuxer buffers the entire script into memory. Adjust this value to set the maximum buffer size, -which in turn, acts as a ceiling for the size of scripts that can be read. -Default is 1 MiB. -

-
- -
-
-

3.25 w64

- -

Sony Wave64 Audio demuxer. -

-

This demuxer accepts the following options: -

-
max_size
-

See the same option for the wav demuxer. -

-
- -
-
-

3.26 wav

- -

RIFF Wave Audio demuxer. -

-

This demuxer accepts the following options: -

-
max_size
-

Specify the maximum packet size in bytes for the demuxed packets. By default -this is set to 0, which means that a sensible value is chosen based on the -input format. -

-
- -
-
-
-

4 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. -

- -
-

4.1 Raw muxers

- -

This section covers raw muxers. They accept a single stream matching -the designated codec. They do not store timestamps or metadata. The -recognized extension is the same as the muxer name unless indicated -otherwise. -

-

It comprises the following muxers. The media type and the eventual -extensions used to automatically selects the muxer from the output -extensions are also shown. -

-
-
‘ac3 audio’
-

Dolby Digital, also known as AC-3. -

-
-
‘adx audio’
-

CRI Middleware ADX audio. -

-

This muxer will write out the total sample count near the start of the -first packet when the output is seekable and the count can be stored -in 32 bits. -

-
-
‘aptx audio’
-

aptX (Audio Processing Technology for Bluetooth) -

-
-
‘aptx_hd audio (aptxdh)’
-

aptX HD (Audio Processing Technology for Bluetooth) audio -

-
-
‘avs2 video (avs, avs2)’
-

AVS2-P2 (Audio Video Standard - Second generation - Part 2) / -IEEE 1857.4 video -

-
-
‘avs3 video (avs3)’
-

AVS3-P2 (Audio Video Standard - Third generation - Part 2) / -IEEE 1857.10 video -

-
-
‘cavsvideo video (cavs)’
-

Chinese AVS (Audio Video Standard - First generation) -

-
-
‘codec2raw audio’
-

Codec 2 audio. -

-

No extension is registered so format name has to be supplied e.g. with -the ffmpeg CLI tool -f codec2raw. -

-
-
‘data any’
-

Generic data muxer. -

-

This muxer accepts a single stream with any codec of any type. The -input stream has to be selected using the -map option with the -ffmpeg CLI tool. -

-

No extension is registered so format name has to be supplied e.g. with -the ffmpeg CLI tool -f data. -

-
-
‘dfpwm audio (dfpwm)’
-

Raw DFPWM1a (Dynamic Filter Pulse With Modulation) audio muxer. -

-
-
‘dirac video (drc, vc2)’
-

BBC Dirac video. -

-

The Dirac Pro codec is a subset and is standardized as SMPTE VC-2. -

-
-
‘dnxhd video (dnxhd, dnxhr)’
-

Avid DNxHD video. -

-

It is standardized as SMPTE VC-3. Accepts DNxHR streams. -

-
-
‘dts audio’
-

DTS Coherent Acoustics (DCA) audio -

-
-
‘eac3 audio’
-

Dolby Digital Plus, also known as Enhanced AC-3 -

-
-
‘evc video (evc)’
-

MPEG-5 Essential Video Coding (EVC) / EVC / MPEG-5 Part 1 EVC video -

-
-
‘g722 audio’
-

ITU-T G.722 audio -

-
-
‘g723_1 audio (tco, rco)’
-

ITU-T G.723.1 audio -

-
-
‘g726 audio’
-

ITU-T G.726 big-endian ("left-justified") audio. -

-

No extension is registered so format name has to be supplied e.g. with -the ffmpeg CLI tool -f g726. -

-
-
‘g726le audio’
-

ITU-T G.726 little-endian ("right-justified") audio. -

-

No extension is registered so format name has to be supplied e.g. with -the ffmpeg CLI tool -f g726le. -

-
-
‘gsm audio’
-

Global System for Mobile Communications audio -

-
-
‘h261 video’
-

ITU-T H.261 video -

-
-
‘h263 video’
-

ITU-T H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2 video -

-
-
‘h264 video (h264, 264)’
-

ITU-T H.264 / MPEG-4 Part 10 AVC video. Bitstream shall be converted -to Annex B syntax if it’s in length-prefixed mode. -

-
-
‘hevc video (hevc, h265, 265)’
-

ITU-T H.265 / MPEG-H Part 2 HEVC video. Bitstream shall be converted -to Annex B syntax if it’s in length-prefixed mode. -

-
-
‘m4v video’
-

MPEG-4 Part 2 video -

-
-
‘mjpeg video (mjpg, mjpeg)’
-

Motion JPEG video -

-
-
‘mlp audio’
-

Meridian Lossless Packing, also known as Packed PCM -

-
-
‘mp2 audio (mp2, m2a, mpa)’
-

MPEG-1 Audio Layer II audio -

-
-
‘mpeg1video video (mpg, mpeg, m1v)’
-

MPEG-1 Part 2 video. -

-
-
‘mpeg2video video (m2v)’
-

ITU-T H.262 / MPEG-2 Part 2 video -

-
-
‘obu video’
-

AV1 low overhead Open Bitstream Units muxer. -

-

Temporal delimiter OBUs will be inserted in all temporal units of the -stream. -

-
-
‘rawvideo video (yuv, rgb)’
-

Raw uncompressed video. -

-
-
‘sbc audio (sbc, msbc)’
-

Bluetooth SIG low-complexity subband codec audio -

-
-
‘truehd audio (thd)’
-

Dolby TrueHD audio -

-
-
‘vc1 video’
-

SMPTE 421M / VC-1 video -

-
- - -
-

4.1.1 Examples

- -
    -
  • Store raw video frames with the ‘rawvideo’ muxer using ffmpeg: -
    -
    ffmpeg -f lavfi -i testsrc -t 10 -s hd1080p testsrc.yuv
-
    - -

    Since the rawvideo muxer do not store the information related to size -and format, this information must be provided when demuxing the file: -

    -
    ffplay -video_size 1920x1080 -pixel_format rgb24 -f rawvideo testsrc.rgb
-
    -
- -
-
-
-

4.2 Raw PCM muxers

-

This section covers raw PCM (Pulse-Code Modulation) audio muxers. -

-

They accept a single stream matching the designated codec. They do not -store timestamps or metadata. The recognized extension is the same as -the muxer name. -

-

It comprises the following muxers. The optional additional extension -used to automatically select the muxer from the output extension is -also shown in parentheses. -

-
-
‘alaw (al)’
-

PCM A-law -

-
-
‘f32be’
-

PCM 32-bit floating-point big-endian -

-
-
‘f32le’
-

PCM 32-bit floating-point little-endian -

-
-
‘f64be’
-

PCM 64-bit floating-point big-endian -

-
-
‘f64le’
-

PCM 64-bit floating-point little-endian -

-
-
‘mulaw (ul)’
-

PCM mu-law -

-
-
‘s16be’
-

PCM signed 16-bit big-endian -

-
-
‘s16le’
-

PCM signed 16-bit little-endian -

-
-
‘s24be’
-

PCM signed 24-bit big-endian -

-
-
‘s24le’
-

PCM signed 24-bit little-endian -

-
-
‘s32be’
-

PCM signed 32-bit big-endian -

-
-
‘s32le’
-

PCM signed 32-bit little-endian -

-
-
‘s8 (sb)’
-

PCM signed 8-bit -

-
-
‘u16be’
-

PCM unsigned 16-bit big-endian -

-
-
‘u16le’
-

PCM unsigned 16-bit little-endian -

-
-
‘u24be’
-

PCM unsigned 24-bit big-endian -

-
-
‘u24le’
-

PCM unsigned 24-bit little-endian -

-
-
‘u32be’
-

PCM unsigned 32-bit big-endian -

-
-
‘u32le’
-

PCM unsigned 32-bit little-endian -

-
-
‘u8 (ub)’
-

PCM unsigned 8-bit -

-
-
‘vidc’
-

PCM Archimedes VIDC -

-
- -
-
-

4.3 MPEG-1/MPEG-2 program stream muxers

- -

This section covers formats belonging to the MPEG-1 and MPEG-2 Systems -family. -

-

The MPEG-1 Systems format (also known as ISO/IEEC 11172-1 or MPEG-1 -program stream) has been adopted for the format of media track stored -in VCD (Video Compact Disc). -

-

The MPEG-2 Systems standard (also known as ISO/IEEC 13818-1) covers -two containers formats, one known as transport stream and one known as -program stream; only the latter is covered here. -

-

The MPEG-2 program stream format (also known as VOB due to the -corresponding file extension) is an extension of MPEG-1 program -stream: in addition to support different codecs for the audio and -video streams, it also stores subtitles and navigation metadata. -MPEG-2 program stream has been adopted for storing media streams in -SVCD and DVD storage devices. -

-

This section comprises the following muxers. -

-
-
‘mpeg (mpg,mpeg)’
-

MPEG-1 Systems / MPEG-1 program stream muxer. -

-
-
‘vcd’
-

MPEG-1 Systems / MPEG-1 program stream (VCD) muxer. -

-

This muxer can be used to generate tracks in the format accepted by -the VCD (Video Compact Disc) storage devices. -

-

It is the same as the ‘mpeg’ muxer with a few differences. -

-
-
‘vob’
-

MPEG-2 program stream (VOB) muxer. -

-
-
‘dvd’
-

MPEG-2 program stream (DVD VOB) muxer. -

-

This muxer can be used to generate tracks in the format accepted by -the DVD (Digital Versatile Disc) storage devices. -

-

This is the same as the ‘vob’ muxer with a few differences. -

-
-
‘svcd (vob)’
-

MPEG-2 program stream (SVCD VOB) muxer. -

-

This muxer can be used to generate tracks in the format accepted by -the SVCD (Super Video Compact Disc) storage devices. -

-

This is the same as the ‘vob’ muxer with a few differences. -

-
- - -
-

4.3.1 Options

-
-
muxrate rate
-

Set user-defined mux rate expressed as a number of bits/s. If not -specied the automatically computed mux rate is employed. Default value -is 0. -

-
-
preload delay
-

Set initial demux-decode delay in microseconds. Default value is -500000. -

-
- -
-
-
-

4.4 MOV/MPEG-4/ISOMBFF muxers

- -

This section covers formats belonging to the QuickTime / MOV family, -including the MPEG-4 Part 14 format and ISO base media file format -(ISOBMFF). These formats share a common structure based on the ISO -base media file format (ISOBMFF). -

-

The MOV format was originally developed for use with Apple QuickTime. -It was later used as the basis for the MPEG-4 Part 1 (later Part 14) -format, also known as ISO/IEC 14496-1. That format was then -generalized into ISOBMFF, also named MPEG-4 Part 12 format, ISO/IEC -14496-12, or ISO/IEC 15444-12. -

-

It comprises the following muxers. -

-
-
‘3gp’
-

Third Generation Partnership Project (3GPP) format for 3G UMTS -multimedia services -

-
-
‘3g2’
-

Third Generation Partnership Project 2 (3GP2 or 3GPP2) format for 3G -CDMA2000 multimedia services, similar to ‘3gp’ with extensions -and limitations -

-
-
‘f4v’
-

Adobe Flash Video format -

-
-
‘ipod’
-

MPEG-4 audio file format, as MOV/MP4 but limited to contain only audio -streams, typically played with the Apple ipod device -

-
-
‘ismv’
-

Microsoft IIS (Internet Information Services) Smooth Streaming -Audio/Video (ISMV or ISMA) format. This is based on MPEG-4 Part 14 -format with a few incompatible variants, used to stream media files -for the Microsoft IIS server. -

-
-
‘mov’
-

QuickTime player format identified by the .mov extension -

-
-
‘mp4’
-

MP4 or MPEG-4 Part 14 format -

-
-
‘psp’
-

PlayStation Portable MP4/MPEG-4 Part 14 format variant. This is based -on MPEG-4 Part 14 format with a few incompatible variants, used to -play files on PlayStation devices. -

-
- - -
-

4.4.1 Fragmentation

- -

The ‘mov’, ‘mp4’, and ‘ismv’ muxers support -fragmentation. Normally, a MOV/MP4 file has all the metadata about all -packets stored in one location. -

-

This data is usually written at the end of the file, but 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. -

-

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

-
frag_duration
-
frag_size
-
min_frag_duration
-
movflags +frag_keyframe
-
movflags +frag_custom
-
- -

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

-
-
-

4.4.2 Options

- -
-
brand brand_string
-

Override major brand. -

-
-
empty_hdlr_name bool
-

Enable to skip writing the name inside a hdlr box. -Default is false. -

-
-
encryption_key key
-

set the media encryption key in hexadecimal format -

-
-
encryption_kid kid
-

set the media encryption key identifier in hexadecimal format -

-
-
encryption_scheme scheme
-

configure the encryption scheme, allowed values are ‘none’, and -‘cenc-aes-ctr’ -

-
-
frag_duration duration
-

Create fragments that are duration microseconds long. -

-
-
frag_interleave number
-

Interleave samples within fragments (max number of consecutive -samples, lower is tighter interleaving, but with more overhead. It is -set to 0 by default. -

-
-
frag_size size
-

create fragments that contain up to size bytes of payload data -

-
-
iods_audio_profile profile
-

specify iods number for the audio profile atom (from -1 to 255), -default is -1 -

-
-
iods_video_profile profile
-

specify iods number for the video profile atom (from -1 to 255), -default is -1 -

-
-
ism_lookahead num_entries
-

specify number of lookahead entries for ISM files (from 0 to 255), -default is 0 -

-
-
min_frag_duration duration
-

do not create fragments that are shorter than duration microseconds long -

-
-
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. -

-
-
mov_gamma gamma
-

specify gamma value for gama atom (as a decimal number from 0 to 10), -default is 0.0, must be set together with + movflags -

-
-
movflags flags
-

Set various muxing switches. The following flags can be used: -

-
‘cmaf’
-

write CMAF (Common Media Application Format) compatible fragmented -MP4 output -

-
-
‘dash’
-

write DASH (Dynamic Adaptive Streaming over HTTP) compatible fragmented -MP4 output -

-
-
‘default_base_moof’
-

Similarly to the ‘omit_tfhd_offset’ flag, 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). -

-
-
‘delay_moov’
-

delay writing the initial moov until the first fragment is cut, or -until the first fragment flush -

-
-
‘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. -

-
-
‘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. -

-
-
‘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.) -

-
-
‘frag_discont’
-

signal that the next fragment is discontinuous from earlier ones -

-
-
‘frag_every_frame’
-

fragment at every frame -

-
-
‘frag_keyframe’
-

start a new fragment at each video keyframe -

-
-
‘global_sidx’
-

write a global sidx index at the start of the file -

-
-
‘isml’
-

create a live smooth streaming feed (for pushing to a publishing point) -

-
-
‘negative_cts_offsets’
-

Enables utilization of version 1 of the CTTS box, in which the CTS offsets can -be negative. This enables the initial sample to have DTS/CTS of zero, and -reduces the need for edit lists for some cases such as video tracks with -B-frames. Additionally, eases conformance with the DASH-IF interoperability -guidelines. -

-

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

-
-
‘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. -

-
-
‘prefer_icc’
-

If writing colr atom prioritise usage of ICC profile if it exists in -stream packet side data. -

-
-
‘rtphint’
-

add RTP hinting tracks to the output file -

-
-
‘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. -

-
-
‘skip_sidx’
-

Skip writing of sidx atom. When bitrate overhead due to sidx atom is -high, this option could be used for cases where sidx atom is not -mandatory. When the ‘global_sidx’ flag is enabled, this option -is ignored. -

-
-
‘skip_trailer’
-

skip writing the mfra/tfra/mfro trailer for fragmented files -

-
-
‘use_metadata_tags’
-

use mdta atom for metadata -

-
-
‘write_colr’
-

write colr atom even if the color info is unspecified. This flag is -experimental, may be renamed or changed, do not use from scripts. -

-
-
‘write_gama’
-

write deprecated gama atom -

-
-
‘hybrid_fragmented’
-

For recoverability - write the output file as a fragmented file. -This allows the intermediate file to be read while being written -(in particular, if the writing process is aborted uncleanly). When -writing is finished, the file is converted to a regular, non-fragmented -file, which is more compatible and allows easier and quicker seeking. -

-

If writing is aborted, the intermediate file can manually be -remuxed to get a regular, non-fragmented file of what had been -written into the unfinished file. -

-
- -
-
movie_timescale scale
-

Set the timescale written in the movie header box (mvhd). -Range is 1 to INT_MAX. Default is 1000. -

-
-
rtpflags flags
-

Add RTP hinting tracks to the output file. -

-

The following flags can be used: -

-
‘h264_mode0’
-

use mode 0 for H.264 in RTP -

-
-
‘latm’
-

use MP4A-LATM packetization instead of MPEG4-GENERIC for AAC -

-
-
‘rfc2190’
-

use RFC 2190 packetization instead of RFC 4629 for H.263 -

-
-
‘send_bye’
-

send RTCP BYE packets when finishing -

-
-
‘skip_rtcp’
-

do not send RTCP sender reports -

-
- -
-
skip_iods bool
-

skip writing iods atom (default value is true) -

-
-
use_editlist bool
-

use edit list (default value is auto) -

-
-
use_stream_ids_as_track_ids bool
-

use stream ids as track ids (default value is false) -

-
-
video_track_timescale scale
-

Set the timescale used for video tracks. Range is 0 to INT_MAX. If -set to 0, the timescale is automatically set based on the -native stream time base. Default is 0. -

-
-
write_btrt bool
-

Force or disable writing bitrate box inside stsd box of a track. The -box contains decoding buffer size (in bytes), maximum bitrate and -average bitrate for the track. The box will be skipped if none of -these values can be computed. Default is -1 or auto, -which will write the box only in MP4 mode. -

-
-
write_prft option
-

Write producer time reference box (PRFT) with a specified time source for the -NTP field in the PRFT box. Set value as ‘wallclock’ to specify timesource -as wallclock time and ‘pts’ to specify timesource as input packets’ PTS -values. -

-
-
write_tmcd bool
-

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). -

-

Setting value to ‘pts’ is applicable only for a live encoding use case, -where PTS values are set as as wallclock time at the source. For example, an -encoding use case with decklink capture source where video_pts and -audio_pts are set to ‘abs_wallclock’. -

-
- -
-
-

4.4.3 Examples

- -
    -
  • Push Smooth Streaming content in real time to a publishing point on -IIS with the ‘ismv’ muxer using ffmpeg: -
    -
    ffmpeg -re <normal input/transcoding options> -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
-
    -
- -
-
-
-

4.5 a64

-

A64 Commodore 64 video muxer. -

-

This muxer accepts a single a64_multi or a64_multi5 -codec video stream. -

-
-
-

4.6 ac4

-

Raw AC-4 audio muxer. -

-

This muxer accepts a single ac4 audio stream. -

- -
-

4.6.1 Options

-
-
write_crc bool
-

when enabled, write a CRC checksum for each packet to the output, -default is false -

-
- -
-
-
-

4.7 adts

-

Audio Data Transport Stream muxer. -

-

It accepts a single AAC stream. -

- -
-

4.7.1 Options

-
-
write_id3v2 bool
-

Enable to write ID3v2.4 tags at the start of the stream. Default is -disabled. -

-
-
write_apetag bool
-

Enable to write APE tags at the end of the stream. Default is -disabled. -

-
-
write_mpeg2 bool
-

Enable to set MPEG version bit in the ADTS frame header to 1 which -indicates MPEG-2. Default is 0, which indicates MPEG-4. -

-
- -
-
-
-

4.8 aea

-

MD STUDIO audio muxer. -

-

This muxer accepts a single ATRAC1 audio stream with either one or two channels -and a sample rate of 44100Hz. -

-

As AEA supports storing the track title, this muxer will also write -the title from stream’s metadata to the container. -

-
-
-

4.9 aiff

-

Audio Interchange File Format muxer. -

- -
-

4.9.1 Options

-
-
write_id3v2 bool
-

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

-
-
id3v2_version bool
-

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

-
- -
-
-
-

4.10 alp

-

High Voltage Software’s Lego Racers game audio muxer. -

-

It accepts a single ADPCM_IMA_ALP stream with no more than 2 channels -and a sample rate not greater than 44100 Hz. -

-

Extensions: tun, pcm -

- -
-

4.10.1 Options

-
-
type type
-

Set file type. -

-

type accepts the following values: -

-
‘tun’
-

Set file type as music. Must have a sample rate of 22050 Hz. -

-
-
‘pcm’
-

Set file type as sfx. -

-
-
‘auto’
-

Set file type as per output file extension. .pcm results in -type pcm else type tun is set. (default) -

-
-
-
- -
-
-
-

4.11 amr

-

3GPP AMR (Adaptive Multi-Rate) audio muxer. -

-

It accepts a single audio stream containing an AMR NB stream. -

-
-
-

4.12 amv

-

AMV (Actions Media Video) format muxer. -

-
-
-

4.13 apm

-

Ubisoft Rayman 2 APM audio muxer. -

-

It accepts a single ADPCM IMA APM audio stream. -

-
-
-

4.14 apng

-

Animated Portable Network Graphics muxer. -

-

It accepts a single APNG video stream. -

- -
-

4.14.1 Options

-
-
final_delay delay
-

Force a delay expressed in seconds after the last frame of each -repetition. Default value is 0.0. -

-
-
plays repetitions
-

specify how many times to play the content, 0 causes an infinte -loop, with 1 there is no loop -

-
- -
-
-

4.14.2 Examples

-
    -
  • Use ffmpeg to generate an APNG output with 2 repetitions, -and with a delay of half a second after the first repetition: -
    -
    ffmpeg -i INPUT -final_delay 0.5 -plays 2 out.apng
-
    -
- -
-
-
-

4.15 argo_asf

-

Argonaut Games ASF audio muxer. -

-

It accepts a single ADPCM audio stream. -

- -
-

4.15.1 Options

-
-
version_major version
-

override file major version, specified as an integer, default value is -2 -

-
-
version_minor version
-

override file minor version, specified as an integer, default value is -1 -

-
-
name name
-

Embed file name into file, if not specified use the output file -name. The name is truncated to 8 characters. -

-
- -
-
-
-

4.16 argo_cvg

-

Argonaut Games CVG audio muxer. -

-

It accepts a single one-channel ADPCM 22050Hz audio stream. -

-

The loop and reverb options set the corresponding -flags in the header which can be later retrieved to process the audio -stream accordingly. -

- -
-

4.16.1 Options

-
-
skip_rate_check bool
-

skip sample rate check (default is false) -

-
-
loop bool
-

set loop flag (default is false) -

-
-
reverb boolean
-

set reverb flag (default is true) -

-
- -
-
-
-

4.17 asf, asf_stream

-

Advanced / Active Systems (or Streaming) Format audio muxer. -

-

The ‘asf_stream’ variant should be selected for streaming. -

-

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

- -
-

4.17.1 Options

-
-
packet_size size
-

Set the muxer packet size as a number of bytes. 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 64Ki. -

-
- -
-
-
-

4.18 ass

-

ASS/SSA (SubStation Alpha) subtitles muxer. -

-

It accepts a single ASS subtitles stream. -

- -
-

4.18.1 Options

-
-
ignore_readorder bool
-

Write dialogue events immediately, even if they are out-of-order, -default is false, otherwise they are cached until the expected -time event is found. -

-
- -
-
-
-

4.19 ast

-

AST (Audio Stream) muxer. -

-

This format is used to play audio on some Nintendo Wii games. -

-

It accepts a single audio stream. -

-

The loopstart and loopend options can be used to -define a section of the file to loop for players honoring such -options. -

- -
-

4.19.1 Options

-
-
loopstart start
-

Specify loop start position expressesd in milliseconds, from -1 -to INT_MAX, in case -1 is set then no loop is specified -(default -1) and the loopend value is ignored. -

-
-
loopend end
-

Specify loop end position expressed in milliseconds, from 0 to -INT_MAX, default is 0, in case 0 is set it -assumes the total stream duration. -

-
- -
-
-
-

4.20 au

-

SUN AU audio muxer. -

-

It accepts a single audio stream. -

-
-
-

4.21 avi

-

Audio Video Interleaved muxer. -

-

AVI is a proprietary format developed by Microsoft, and later formally specified -through the Open DML specification. -

-

Because of differences in players implementations, it might be required to set -some options to make sure that the generated output can be correctly played by -the target player. -

- -
-

4.21.1 Options

-
-
flipped_raw_rgb bool
-

If set to true, store positive height for raw RGB bitmaps, which -indicates bitmap is stored bottom-up. Note that this option does not flip the -bitmap which has to be done manually beforehand, e.g. by using the ‘vflip’ -filter. Default is false and indicates bitmap is stored top down. -

-
-
reserve_index_space size
-

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. -

-

Default value is 0. -

-
-
write_channel_mask bool
-

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). -

-
- -
-
-
-

4.22 avif

-

AV1 (Alliance for Open Media Video codec 1) image format muxer. -

-

This muxers stores images encoded using the AV1 codec. -

-

It accepts one or two video streams. In case two video streams are -provided, the second one shall contain a single plane storing the -alpha mask. -

-

In case more than one image is provided, the generated output is -considered an animated AVIF and the number of loops can be specified -with the loop option. -

-

This is based on the specification by Alliance for Open Media at url -https://aomediacodec.github.io/av1-avif. -

- -
-

4.22.1 Options

-
-
loop count
-

number of times to loop an animated AVIF, 0 specify an infinite -loop, default is 0 -

-
-
movie_timescale timescale
-

Set the timescale written in the movie header box (mvhd). -Range is 1 to INT_MAX. Default is 1000. -

-
- -
-
-
-

4.23 avm2

-

ShockWave Flash (SWF) / ActionScript Virtual Machine 2 (AVM2) format muxer. -

-

It accepts one audio stream, one video stream, or both. -

-
-
-

4.24 bit

-

G.729 (.bit) file format muxer. -

-

It accepts a single G.729 audio stream. -

-
-
-

4.25 caf

-

Apple CAF (Core Audio Format) muxer. -

-

It accepts a single audio stream. -

-
-
-

4.26 codec2

-

Codec2 audio audio muxer. -

-

It accepts a single codec2 audio stream. -

-
-
-

4.27 chromaprint

-

Chromaprint fingerprinter muxers. -

-

To enable compilation of this filter you need to configure FFmpeg with ---enable-chromaprint. -

-

This muxer feeds audio data to the Chromaprint library, which -generates a fingerprint for the provided audio data. See: -https://acoustid.org/chromaprint -

-

It takes a single signed native-endian 16-bit raw audio stream of at -most 2 channels. -

- -
-

4.27.1 Options

-
-
algorithm version
-

Select version of algorithm to fingerprint with. Range is 0 to -4. Version 3 enables silence detection. Default is 1. -

-
-
fp_format format
-

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

-
‘base64’
-

Base64 compressed fingerprint (default) -

-
-
‘compressed’
-

Binary compressed fingerprint -

-
-
‘raw’
-

Binary raw fingerprint -

-
- -
-
silence_threshold threshold
-

Threshold for detecting silence. Range is from -1 to -32767, where -1 disables silence detection. Silence -detection can only be used with version 3 of the algorithm. -

-

Silence detection must be disabled for use with the AcoustID -service. Default is -1. -

-
- -
-
-
-

4.28 crc

-

CRC (Cyclic Redundancy Check) muxer. -

-

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. -

- -
-

4.28.1 Examples

-
    -
  • Use ffmpeg to compute the CRC of the input, and store it in -the file out.crc: -
    -
    ffmpeg -i INPUT -f crc out.crc
-
    - -
  • Use ffmpeg to 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 -
-
    -
- -
-
-
-

4.29 dash

-

Dynamic Adaptive Streaming over HTTP (DASH) muxer. -

-

This muxer creates segments and manifest files according to the -MPEG-DASH standard ISO/IEC 23009-1:2014 and following standard -updates. -

-

For more information see: -

- -

This muxer creates an MPD (Media Presentation Description) manifest -file and segment files for each stream. Segment files are placed in -the same directory of the MPD manifest file. -

-

The segment filename might contain pre-defined identifiers used in the -manifest SegmentTemplate section as defined in section -5.3.9.4.4 of the standard. -

-

Available identifiers are $RepresentationID$, $Number$, -$Bandwidth$, and $Time$. In addition to the standard -identifiers, an ffmpeg-specific $ext$ identifier is also -supported. When specified, ffmpeg will replace $ext$ -in the file name with muxing format’s extensions such as mp4, -webm etc. -

- -
-

4.29.1 Options

-
-
adaptation_sets adaptation_sets
-

Assign streams to adaptation sets, specified in the MPD manifest -AdaptationSets section. -

-

An adaptation set contains a set of one or more streams accessed as a -single subset, e.g. corresponding streams encoded at different size -selectable by the user depending on the available bandwidth, or to -different audio streams with a different language. -

-

Each adaptation set is specified with the syntax: -

-
id=index,streams=streams
-
- -

where index must be a numerical index, and streams is a -sequence of ,-separated stream indices. Multiple adaptation -sets can be specified, separated by spaces. -

-

To map all video (or audio) streams to an adaptation set, v (or -a) can be used as stream identifier instead of IDs. -

-

When no assignment is defined, this defaults to an adaptation set for -each stream. -

-

The following optional fields can also be specified: -

-
-
descriptor
-

Define the descriptor as defined by ISO/IEC 23009-1:2014/Amd.2:2015. -

-

For example: -

-
<SupplementalProperty schemeIdUri=\"urn:mpeg:dash:srd:2014\" value=\"0,0,0,1,1,2,2\"/>
-
- -

The descriptor string should be a self-closing XML tag. -

-
-
frag_duration
-

Override the global fragment duration specified with the -frag_duration option. -

-
-
frag_type
-

Override the global fragment type specified with the -frag_type option. -

-
-
seg_duration
-

Override the global segment duration specified with the -seg_duration option. -

-
-
trick_id
-

Mark an adaptation set as containing streams meant to be used for -Trick Mode for the referenced adaptation set. -

-
- -

A few examples of possible values for the adaptation_sets -option follow: -

-
id=0,seg_duration=2,frag_duration=1,frag_type=duration,streams=v id=1,seg_duration=2,frag_type=none,streams=a
-
- -
-
id=0,seg_duration=2,frag_type=none,streams=0 id=1,seg_duration=10,frag_type=none,trick_id=0,streams=1
-
- -
-
dash_segment_type type
-

Set DASH segment files type. -

-

Possible values: -

-
‘auto’
-

The dash segment files format will be selected based on the stream -codec. This is the default mode. -

-
‘mp4’
-

the dash segment files will be in ISOBMFF/MP4 format -

-
‘webm’
-

the dash segment files will be in WebM format -

-
- -
-
extra_window_size size
-

Set the maximum number of segments kept outside of the manifest before -removing from disk. -

-
-
format_options options_list
-

Set container format (mp4/webm) options using a :-separated list of -key=value parameters. Values containing : special characters must be -escaped. -

-
-
frag_duration duration
-

Set the length in seconds of fragments within segments, fractional -value can also be set. -

-
-
frag_type type
-

Set the type of interval for fragmentation. -

-

Possible values: -

-
‘auto’
-

set one fragment per segment -

-
-
‘every_frame’
-

fragment at every frame -

-
-
‘duration’
-

fragment at specific time intervals -

-
-
‘pframes’
-

fragment at keyframes and following P-Frame reordering (Video only, -experimental) -

-
- -
-
global_sidx bool
-

Write global SIDX atom. Applicable only for single file, mp4 -output, non-streaming mode. -

-
-
hls_master_name file_name
-

HLS master playlist name. Default is master.m3u8. -

-
-
hls_playlist bool
-

Generate HLS playlist files. The master playlist is generated with -filename specified by the hls_master_name option. One media -playlist file is generated for each stream with filenames -media_0.m3u8, media_1.m3u8, etc. -

-
-
http_opts http_opts
-

Specify a list of :-separated key=value options to pass to the -underlying HTTP protocol. Applicable only for HTTP output. -

-
-
http_persistent bool
-

Use persistent HTTP connections. Applicable only for HTTP output. -

-
-
http_user_agent user_agent
-

Override User-Agent field in HTTP header. Applicable only for HTTP -output. -

-
-
ignore_io_errors bool
-

Ignore IO errors during open and write. Useful for long-duration runs -with network output. This is disabled by default. -

-
-
index_correction bool
-

Enable or disable segment index correction logic. Applicable only when -use_template is enabled and use_timeline is -disabled. This is disabled by default. -

-

When enabled, the logic monitors the flow of segment indexes. If a -streams’s segment index value is not at the expected real time -position, then the logic corrects that index value. -

-

Typically this logic is needed in live streaming use cases. The -network bandwidth fluctuations are common during long run -streaming. Each fluctuation can cause the segment indexes fall behind -the expected real time position. -

-
-
init_seg_name init_name
-

DASH-templated name to use for the initialization segment. Default is -init-stream$RepresentationID$.$ext$. $ext$ is replaced -with the file name extension specific for the segment format. -

-
-
ldash bool
-

Enable Low-latency Dash by constraining the presence and values of -some elements. This is disabled by default. -

-
-
lhls bool
-

Enable Low-latency HLS (LHLS). Add #EXT-X-PREFETCH tag with -current segment’s URI. hls.js player folks are trying to standardize -an open LHLS spec. The draft spec is available at -https://github.com/video-dev/hlsjs-rfcs/blob/lhls-spec/proposals/0001-lhls.md. -

-

This option tries to comply with the above open spec. It enables -streaming and hls_playlist options automatically. -This is an experimental feature. -

-

Note: This is not Apple’s version LHLS. See -https://datatracker.ietf.org/doc/html/draft-pantos-hls-rfc8216bis -

-
-
master_m3u8_publish_rate segment_intervals_count
-

Publish master playlist repeatedly every after specified number of -segment intervals. -

-
-
max_playback_rate rate
-

Set the maximum playback rate indicated as appropriate for the -purposes of automatically adjusting playback latency and buffer -occupancy during normal playback by clients. -

-
-
media_seg_name segment_name
-

DASH-templated name to use for the media segments. Default is -chunk-stream$RepresentationID$-$Number%05d$.$ext$. $ext$ -is replaced with the file name extension specific for the segment -format. -

-
-
method method
-

Use the given HTTP method to create output files. Generally set to PUT -or POST. -

-
-
min_playback_rate rate
-

Set the minimum playback rate indicated as appropriate for the -purposes of automatically adjusting playback latency and buffer -occupancy during normal playback by clients. -

-
-
mpd_profile flags
-

Set one or more MPD manifest profiles. -

-

Possible values: -

-
‘dash’
-

MPEG-DASH ISO Base media file format live profile -

-
‘dvb_dash’
-

DVB-DASH profile -

-
- -

Default value is dash. -

-
-
remove_at_exit bool
-

Enable or disable removal of all segments when finished. This is -disabled by default. -

-
-
seg_duration duration
-

Set the segment length in seconds (fractional value can be set). The -value is treated as average segment duration when the -use_template option is enabled and the use_timeline -option is disabled and as minimum segment duration for all the other -use cases. -

-

Default value is 5. -

-
-
single_file bool
-

Enable or disable storing all segments in one file, accessed using -byte ranges. This is disabled by default. -

-

The name of the single file can be specified with the -single_file_name option, if not specified assume the basename -of the manifest file with the output format extension. -

-
-
single_file_name file_name
-

DASH-templated name to use for the manifest baseURL -element. Imply that the single_file option is set to -true. In the template, $ext$ is replaced with the file -name extension specific for the segment format. -

-
-
streaming bool
-

Enable or disable chunk streaming mode of output. In chunk streaming -mode, each frame will be a moof fragment which forms a -chunk. This is disabled by default. -

-
-
target_latency target_latency
-

Set an intended target latency in seconds for serving (fractional -value can be set). Applicable only when the streaming and -write_prft options are enabled. This is an informative fields -clients can use to measure the latency of the service. -

-
-
timeout timeout
-

Set timeout for socket I/O operations expressed in seconds (fractional -value can be set). Applicable only for HTTP output. -

-
-
update_period period
-

Set the MPD update period, for dynamic content. The unit is -second. If set to 0, the period is automatically computed. -

-

Default value is 0. -

-
-
use_template bool
-

Enable or disable use of SegmentTemplate instead of -SegmentList in the manifest. This is enabled by default. -

-
-
use_timeline bool
-

Enable or disable use of SegmentTimeline within the -SegmentTemplate manifest section. This is enabled by default. -

-
-
utc_timing_url url
-

URL of the page that will return the UTC timestamp in ISO -format, for example https://time.akamai.com/?iso -

-
-
window_size size
-

Set the maximum number of segments kept in the manifest, discard the -oldest one. This is useful for live streaming. -

-

If the value is 0, all segments are kept in the -manifest. Default value is 0. -

-
-
write_prft write_prft
-

Write Producer Reference Time elements on supported streams. This also -enables writing prft boxes in the underlying muxer. Applicable only -when the utc_url option is enabled. It is set to auto by -default, in which case the muxer will attempt to enable it only in -modes that require it. -

-
- -
-
-

4.29.2 Example

-

Generate a DASH output reading from an input source in realtime using -ffmpeg. -

-

Two multimedia streams are generated from the input file, both -containing a video stream encoded through ‘libx264’, and an audio -stream encoded with ‘libfdk_aac’. The first multimedia stream -contains video with a bitrate of 800k and audio at the default rate, -the second with video scaled to 320x170 pixels at 300k and audio -resampled at 22005 Hz. -

-

The window_size option keeps only the latest 5 segments with -the default duration of 5 seconds. -

-
-
ffmpeg -re -i <input> -map 0 -map 0 -c:a libfdk_aac -c:v libx264 \
--b:v:0 800k -profile:v:0 main \
--b:v:1 300k -s:v:1 320x170 -profile:v:1 baseline -ar:a:1 22050 \
--bf 1 -keyint_min 120 -g 120 -sc_threshold 0 -b_strategy 0 \
--use_timeline 1 -use_template 1 -window_size 5 \
--adaptation_sets "id=0,streams=v id=1,streams=a" \
--f dash /path/to/out.mpd
-
- -
-
-
-

4.30 daud

-

D-Cinema audio muxer. -

-

It accepts a single 6-channels audio stream resampled at 96000 Hz -encoded with the ‘pcm_24daud’ codec. -

- -
-

4.30.1 Example

-

Use ffmpeg to mux input audio to a ‘5.1’ channel layout -resampled at 96000Hz: -

-
ffmpeg -i INPUT -af aresample=96000,pan=5.1 slow.302
-
- -

For ffmpeg versions before 7.0 you might have to use the ‘asetnsamples’ -filter to limit the muxed packet size, because this format does not support -muxing packets larger than 65535 bytes (3640 samples). For newer ffmpeg -versions audio is automatically packetized to 36000 byte (2000 sample) packets. -

-
-
-
-

4.31 dv

-

DV (Digital Video) muxer. -

-

It accepts exactly one ‘dvvideo’ video stream and at most two -‘pcm_s16’ audio streams. More constraints are defined by the -property of the video, which must correspond to a DV video supported -profile, and on the framerate. -

- -
-

4.31.1 Example

-

Use ffmpeg to convert the input: -

-
ffmpeg -i INPUT -s:v 720x480 -pix_fmt yuv411p -r 29.97 -ac 2 -ar 48000 -y out.dv
-
- -
-
-
-

4.32 ffmetadata

-

FFmpeg metadata muxer. -

-

This muxer writes the streams metadata in the ‘ffmetadata’ -format. -

-

See the Metadata chapter for -information about the format. -

- -
-

4.32.1 Example

- -

Use ffmpeg to extract metadata from an input file to a metadata.ffmeta -file in ‘ffmetadata’ format: -

-
ffmpeg -i INPUT -f ffmetadata metadata.ffmeta
-
- -
-
-
-

4.33 fifo

-

FIFO (First-In First-Out) muxer. -

-

The ‘fifo’ pseudo-muxer allows the separation of encoding and -muxing by using a 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. -

-

The target muxer is either selected from the output name or specified -through the fifo_format option. -

-

The behavior of the ‘fifo’ muxer if the queue fills up or if the -output fails (e.g. if a packet cannot be written to the output) 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 the FIFO queue fills up. -
- -

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

- -
-

4.33.1 Options

-
-
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 -false. -

-
-
drop_pkts_on_overflow bool
-

If set to 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 false, so in -such cases the encoder will be blocked until the muxer processes some -of the packets and none of them is lost. -

-
-
fifo_format format_name
-

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

-
-
format_opts options
-

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

-
-
max_recovery_attempts count
-

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

-
-
queue_size size
-

Specify size of the queue as a number of packets. Default value is -60. -

-
-
recover_any_error bool
-

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

-
-
recovery_wait_streamtime bool
-

If set to false, the real time is used when waiting for the -recovery attempt (i.e. the recovery will be attempted after the time -specified by the recovery_wait_time option). -

-

If set to true, the time of the processed stream is taken into -account instead (i.e. the recovery will be attempted after discarding -the packets corresponding to the recovery_wait_time option). -

-

By default this option is set to false. -

-
-
recovery_wait_time duration
-

Specify waiting time in seconds before the next recovery attempt after -previous unsuccessful recovery attempt. Default value is 5. -

-
-
restart_with_keyframe bool
-

Specify whether to wait for the keyframe after recovering from -queue overflow or failure. This option is set to false by default. -

-
-
timeshift duration
-

Buffer the specified amount of packets and delay writing the -output. Note that the value of the queue_size option must be -big enough to store the packets for timeshift. At the end of the input -the fifo buffer is flushed at realtime speed. -

-
- -
-
-

4.33.2 Example

- -

Use ffmpeg to stream to an 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 \
-  -drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 \
-  -map 0:v -map 0:a rtmp://example.com/live/stream_name
-
- -
-
-
-

4.34 film_cpk

-

Sega film (.cpk) muxer. -

-

This format was used as internal format for several Sega games. -

-

For more information regarding the Sega film file format, visit -http://wiki.multimedia.cx/index.php?title=Sega_FILM. -

-

It accepts at maximum one ‘cinepak’ or raw video stream, and at -maximum one audio stream. -

-
-
-

4.35 filmstrip

-

Adobe Filmstrip muxer. -

-

This format is used by several Adobe tools to store a generated filmstrip export. It -accepts a single raw video stream. -

-
-
-

4.36 fits

-

Flexible Image Transport System (FITS) muxer. -

-

This image format is used to store astronomical data. -

-

For more information regarding the format, visit -https://fits.gsfc.nasa.gov. -

-
-
-

4.37 flac

-

Raw FLAC audio muxer. -

-

This muxer accepts exactly one FLAC audio stream. Additionally, it is possible to add -images with disposition ‘attached_pic’. -

- -
-

4.37.1 Options

-
-
write_header bool
-

write the file header if set to true, default is true -

-
- -
-
-

4.37.2 Example

-

Use ffmpeg to store the audio stream from an input file, -together with several pictures used with ‘attached_pic’ -disposition: -

-
ffmpeg -i INPUT -i pic1.png -i pic2.jpg -map 0:a -map 1 -map 2 -disposition:v attached_pic OUTPUT
-
- -
-
-
-

4.38 flv

-

Adobe Flash Video Format muxer. -

- -
-

4.38.1 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. -

-
-
-
- -
-
-
-

4.39 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, 0xCRC
-
- -

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

- -
-

4.39.1 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. -

-
-
-
-

4.40 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. -

-
-
- - -
-

4.40.1 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. -

-
-
-
-

4.41 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. -

- -
-

4.41.1 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. -

-
-
-
-

4.42 gif

-

Animated GIF muxer. -

-

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

- -
-

4.42.1 Options

-
-
loop bool
-

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

-
-
final_delay 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. -

-
- -
-
-

4.42.2 Example

-

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"
-
- -
-
-
-

4.43 gxf

-

General eXchange Format (GXF) muxer. -

-

GXF was developed by Grass Valley Group, then standardized by SMPTE as SMPTE -360M and was extended in SMPTE RDD 14-2007 to include high-definition video -resolutions. -

-

It accepts at most one video stream with codec ‘mjpeg’, or -‘mpeg1video’, or ‘mpeg2video’, or ‘dvvideo’ with resolution -‘512x480’ or ‘608x576’, and several audio streams with rate 48000Hz -and codec ‘pcm16_le’. -

-
-
-

4.44 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. -

-
-
- - -
-

4.44.1 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. -

-
-
-
-

4.45 hds

-

HTTP Dynamic Streaming (HDS) muxer. -

-

HTTP dynamic streaming, or HDS, is an adaptive bitrate streaming method -developed by Adobe. HDS delivers MP4 video content over HTTP connections. HDS -can be used for on-demand streaming or live streaming. -

-

This muxer creates an .f4m (Adobe Flash Media Manifest File) manifest, an .abst -(Adobe Bootstrap File) for each stream, and segment files in a directory -specified as the output. -

-

These needs to be accessed by an HDS player throuhg HTTPS for it to be able to -perform playback on the generated stream. -

- -
-

4.45.1 Options

-
-
extra_window_size int
-

number of fragments kept outside of the manifest before removing from disk -

-
-
min_frag_duration microseconds
-

minimum fragment duration (in microseconds), default value is 1 second -(10000000) -

-
-
remove_at_exit bool
-

remove all fragments when finished when set to true -

-
-
window_size int
-

number of fragments kept in the manifest, if set to a value different from -0. By default all segments are kept in the output directory. -

-
- -
-
-

4.45.2 Example

-

Use ffmpeg to generate HDS files to the output.hds directory in -real-time rate: -

-
ffmpeg -re -i INPUT -f hds -b:v 200k output.hds
-
- -
-
-
-

4.46 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. -

-

Make sure to require a closed GOP when encoding and to set the GOP -size to fit your segment time constraint. -

-

For example, to convert an input file with ffmpeg: -

-
ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 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. -

- -
-

4.46.1 Options

-
-
hls_init_time duration
-

Set the initial target segment length. Default value is 0. -

-

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

-

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 duration
-

Set the target segment length. Default value is 2. -

-

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

Set the number of unreferenced segments to keep on disk before hls_flags delete_segments -deletes them. Increase this to allow continue clients to download segments which -were recently referenced in the playlist. Default value is 1, meaning segments older than -hls_list_size+1 will be deleted. -

-
-
hls_start_number_source 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 start numbers according to the start_number option value. -

-
-
epoch
-

Set the start number as the seconds since epoch (1970-01-01 00:00:00). -

-
-
epoch_us
-

Set the start number as the microseconds since epoch (1970-01-01 00:00:00). -

-
-
datetime
-

Set the start number 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 bool
-

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 the hls_flags option is set with -‘single_file’, filename is used as a string format with the -segment number appended. -

-

For example: -

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

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

-

filename may contain a full path or relative path specification, -but only the file name part without any path 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 strftime_mkdir is set, the whole expanded value of filename will be written into the m3u8 segment list. -

-

When var_stream_map is set with two or more variant streams, the -filename pattern must contain the string "%v", and this string will be -expanded to the position of variant stream index in the generated segment file -names. -

-

For example: -

-
ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
-  -map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0 v:1,a:1" \
-  -hls_segment_filename 'file_%v_%03d.ts' out_%v.m3u8
-
- -

will produce the playlists segment file sets: -file_0_000.ts, file_0_001.ts, file_0_002.ts, etc. and -file_1_000.ts, file_1_001.ts, file_1_002.ts, etc. -

-

The string "%v" may be present in the filename or in the last directory name -containing the file, but only in one of them. (Additionally, %v may appear multiple times in the last -sub-directory or filename.) If the string %v is present in the directory name, then -sub-directories are created after expanding the directory name pattern. This -enables creation of segments corresponding to different variant streams in -subdirectories. -

-

For example: -

-
ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
-  -map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0 v:1,a:1" \
-  -hls_segment_filename 'vs%v/file_%03d.ts' vs%v/out.m3u8
-
-

will produce the playlists segment file sets: -vs0/file_000.ts, vs0/file_001.ts, vs0/file_002.ts, etc. and -vs1/file_000.ts, vs1/file_001.ts, vs1/file_002.ts, etc. -

-
-
strftime bool
-

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 set ‘second_level_segment_index’ in the hls_flag and -%%d will be the specifier. -

-

For example: -

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

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. -

-

For example: -

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

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

-
-
strftime_mkdir bool
-

Used together with strftime, it will create all subdirectories which -are present in the expanded values of option hls_segment_filename. -

-

For example: -

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

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. -

-

For example: -

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

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_segment_options options_list
-

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

-
-
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 if hls_flags periodic_rekey is enabled. -

-

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_enc bool
-

Enable (1) or disable (0) the AES128 encryption. -When enabled every segment generated is encrypted and the encryption key -is saved as playlist name.key. -

-
-
hls_enc_key key
-

Specify a 16-octet key to encrypt the segments, by default it is randomly -generated. -

-
-
hls_enc_key_url keyurl
-

If set, keyurl is prepended instead of baseurl to the key filename -in the playlist. -

-
-
hls_enc_iv iv
-

Specify the 16-octet initialization vector for every segment instead of the -autogenerated ones. -

-
-
hls_segment_type flags
-

Possible values: -

-
-
‘mpegts’
-

Output segment files in MPEG-2 Transport Stream format. This is -compatible with all HLS versions. -

-
-
‘fmp4’
-

Output segment files in fragmented MP4 format, similar to MPEG-DASH. -fmp4 files may be used in HLS version 7 and above. -

-
- -
-
hls_fmp4_init_filename filename
-

Set filename for the fragment files header file, default filename is init.mp4. -

-

When strftime is enabled, filename is expanded to the segment filename with localtime. -

-

For example: -

-
ffmpeg -i in.nut -hls_segment_type fmp4 -strftime 1 -hls_fmp4_init_filename "%s_init.mp4" out.m3u8
-
-

will produce init like this 1602678741_init.mp4. -

-
-
hls_fmp4_init_resend bool
-

Resend init file after m3u8 file refresh every time, default is 0. -

-

When var_stream_map is set with two or more variant streams, the -filename pattern must contain the string "%v", this string specifies -the position of variant stream index in the generated init file names. -The string "%v" may be present in the filename or in the last directory name -containing the file. If the string is present in the directory name, then -sub-directories are created after expanding the directory name pattern. This -enables creation of init files corresponding to different variant streams in -subdirectories. -

-
-
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. -If there are no other features requiring higher HLS versions be used, -then this will allow ffmpeg to output a HLS version 2 m3u8. -

-
-
‘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. -

-
-
‘periodic_rekey’
-

The file specified by hls_key_info_file will be checked periodically and -detect updates to the encryption info. Be sure to replace this file atomically, -including the file containing the AES encryption key. -

-
-
‘independent_segments’
-

Add the #EXT-X-INDEPENDENT-SEGMENTS tag to playlists that has video segments -and when all the segments of that playlist are guaranteed to start with a key frame. -

-
-
‘iframes_only’
-

Add the #EXT-X-I-FRAMES-ONLY tag to playlists that has video segments -and can play only I-frames in the #EXT-X-BYTERANGE mode. -

-
-
‘split_by_time’
-

Allow segments to start on frames other than key frames. This improves -behavior on some players when the time between key frames 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’
-

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

-
-
‘second_level_segment_size’
-

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

-
-
‘second_level_segment_duration’
-

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

-

For example: -

-
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 \
-   -strftime 1 -strftime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
-
-

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. -

-

This flag also affects how m3u8 playlist files are created. If this flag is set, -all playlist files will be written into a temporary file and renamed after they -are complete, similarly as segments are handled. But playlists with file -protocol and with hls_playlist_type type other than ‘vod’ are -always written into a temporary file regardless of this flag. -

-

Master playlist files specified with master_pl_name, if any, with -file protocol, are always written into temporary file regardless of this -flag if master_pl_publish_rate value is other than zero. -

-
- -
-
hls_playlist_type type
-

If type is ‘event’, emit #EXT-X-PLAYLIST-TYPE:EVENT in the m3u8 -header. This forces hls_list_size to 0; the playlist can only be -appended to. -

-

If type is ‘vod’, emit #EXT-X-PLAYLIST-TYPE:VOD in the m3u8 -header. This forces hls_list_size to 0; the playlist must not change. -

-
-
method method
-

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

-

For example: -

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

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. -

-
-
http_user_agent agent
-

Override User-Agent field in HTTP header. Applicable only for HTTP output. -

-
-
var_stream_map stream_map
-

Specify a map string defining how to group the audio, video and subtitle streams -into different variant streams. The variant stream groups are separated by -space. -

-

Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are -the keys to specify audio, video and subtitle streams respectively. -Allowed values are 0 to 9 (limited just based on practical usage). -

-

When there are two or more variant streams, the output filename pattern must -contain the string "%v": this string specifies the position of variant stream -index in the output media playlist filenames. The string "%v" may be present in -the filename or in the last directory name containing the file. If the string is -present in the directory name, then sub-directories are created after expanding -the directory name pattern. This enables creation of variant streams in -subdirectories. -

-

A few examples follow. -

-
    -
  • Create two hls variant streams. The first variant stream will contain video -stream of bitrate 1000k and audio stream of bitrate 64k and the second variant -stream will contain video stream of bitrate 256k and audio stream of bitrate -32k. Here, two media playlist with file names out_0.m3u8 and -out_1.m3u8 will be created. -
    -
    ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
-  -map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0 v:1,a:1" \
-  http://example.com/live/out_%v.m3u8
-
    - -
  • If you want something meaningful text instead of indexes in result names, you -may specify names for each or some of the variants. The following example will -create two hls variant streams as in the previous one. But here, the two media -playlist with file names out_my_hd.m3u8 and out_my_sd.m3u8 will be -created. -
    -
    ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
-  -map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0,name:my_hd v:1,a:1,name:my_sd" \
-  http://example.com/live/out_%v.m3u8
-
    - -
  • Create three hls variant streams. The first variant stream will be a video only -stream with video bitrate 1000k, the second variant stream will be an audio only -stream with bitrate 64k and the third variant stream will be a video only stream -with bitrate 256k. Here, three media playlist with file names out_0.m3u8, -out_1.m3u8 and out_2.m3u8 will be created. -
    -
    ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
-  -map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
-  http://example.com/live/out_%v.m3u8
-
    - -
  • Create the variant streams in subdirectories. Here, the first media playlist is -created at http://example.com/live/vs_0/out.m3u8 and the second one at -http://example.com/live/vs_1/out.m3u8. -
    -
    ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
-  -map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0 v:1,a:1" \
-  http://example.com/live/vs_%v/out.m3u8
-
    - -
  • Create two audio only and two video only variant streams. In addition to the -#EXT-X-STREAM-INF tag for each variant stream in the master playlist, the -#EXT-X-MEDIA tag is also added for the two audio only variant streams and -they are mapped to the two video only variant streams with audio group names -’aud_low’ and ’aud_high’. -By default, a single hls variant containing all the encoded streams is created. -
    -
    ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k -b:v:1 3000k  \
-  -map 0:a -map 0:a -map 0:v -map 0:v -f hls \
-  -var_stream_map "a:0,agroup:aud_low a:1,agroup:aud_high v:0,agroup:aud_low v:1,agroup:aud_high" \
-  -master_pl_name master.m3u8 \
-  http://example.com/live/out_%v.m3u8
-
    - -
  • -Create two audio only and one video only variant streams. In addition to the -#EXT-X-STREAM-INF tag for each variant stream in the master playlist, the -#EXT-X-MEDIA tag is also added for the two audio only variant streams and -they are mapped to the one video only variant streams with audio group name -’aud_low’, and the audio group have default stat is NO or YES. -By default, a single hls variant containing all the encoded streams is created. -
    -
    ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
-  -map 0:a -map 0:a -map 0:v -f hls \
-  -var_stream_map "a:0,agroup:aud_low,default:yes a:1,agroup:aud_low v:0,agroup:aud_low" \
-  -master_pl_name master.m3u8 \
-  http://example.com/live/out_%v.m3u8
-
    - -
  • Create two audio only and one video only variant streams. In addition to the -#EXT-X-STREAM-INF tag for each variant stream in the master playlist, the -#EXT-X-MEDIA tag is also added for the two audio only variant streams and -they are mapped to the one video only variant streams with audio group name -’aud_low’, and the audio group have default stat is NO or YES, and one audio -have and language is named ENG, the other audio language is named CHN. By -default, a single hls variant containing all the encoded streams is created. -
    -
    ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
-  -map 0:a -map 0:a -map 0:v -f hls \
-  -var_stream_map "a:0,agroup:aud_low,default:yes,language:ENG a:1,agroup:aud_low,language:CHN v:0,agroup:aud_low" \
-  -master_pl_name master.m3u8 \
-  http://example.com/live/out_%v.m3u8
-
    - -
  • Create a single variant stream. Add the #EXT-X-MEDIA tag with -TYPE=SUBTITLES in the master playlist with webvtt subtitle group name -’subtitle’ and optional subtitle name, e.g. ’English’. Make sure the input -file has one text subtitle stream at least. -
    -
    ffmpeg -y -i input_with_subtitle.mkv \
- -b:v:0 5250k -c:v h264 -pix_fmt yuv420p -profile:v main -level 4.1 \
- -b:a:0 256k \
- -c:s webvtt -c:a mp2 -ar 48000 -ac 2 -map 0:v -map 0:a:0 -map 0:s:0 \
- -f hls -var_stream_map "v:0,a:0,s:0,sgroup:subtitle,sname:English" \
- -master_pl_name master.m3u8 -t 300 -hls_time 10 -hls_init_time 4 -hls_list_size \
- 10 -master_pl_publish_rate 10 -hls_flags \
- delete_segments+discont_start+split_by_time ./tmp/video.m3u8
-
    -
- -
-
cc_stream_map cc_stream_map
-

Map string which specifies different closed captions groups and their -attributes. The closed captions stream groups are separated by space. -

-

Expected string format is like this -"ccgroup:<group name>,instreamid:<INSTREAM-ID>,language:<language code> ....". -’ccgroup’ and ’instreamid’ are mandatory attributes. ’language’ is an optional -attribute. -

-

The closed captions groups configured using this option are mapped to different -variant streams by providing the same ’ccgroup’ name in the -var_stream_map string. -

-

For example: -

-
ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
-  -a53cc:0 1 -a53cc:1 1 \
-  -map 0:v -map 0:a -map 0:v -map 0:a -f hls \
-  -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en ccgroup:cc,instreamid:CC2,language:sp" \
-  -var_stream_map "v:0,a:0,ccgroup:cc v:1,a:1,ccgroup:cc" \
-  -master_pl_name master.m3u8 \
-  http://example.com/live/out_%v.m3u8
-
-

will add two #EXT-X-MEDIA tags with TYPE=CLOSED-CAPTIONS in the -master playlist for the INSTREAM-IDs ’CC1’ and ’CC2’. Also, it will add -CLOSED-CAPTIONS attribute with group name ’cc’ for the two output variant -streams. -

-

If var_stream_map is not set, then the first available ccgroup in -cc_stream_map is mapped to the output variant stream. -

-

For example: -

-
ffmpeg -re -i in.ts -b:v 1000k -b:a 64k -a53cc 1 -f hls \
-  -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en" \
-  -master_pl_name master.m3u8 \
-  http://example.com/live/out.m3u8
-
-

this will add #EXT-X-MEDIA tag with TYPE=CLOSED-CAPTIONS in the -master playlist with group name ’cc’, language ’en’ (english) and INSTREAM-ID -’CC1’. Also, it will add CLOSED-CAPTIONS attribute with group name ’cc’ -for the output variant stream. -

-
-
master_pl_name name
-

Create HLS master playlist with the given name. -

-

For example: -

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

creates an HLS master playlist with name master.m3u8 which is published -at http://example.com/live/. -

-
-
master_pl_publish_rate count
-

Publish master play list repeatedly every after specified number of segment intervals. -

-

For example: -

-
ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
--hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
-
-

creates an HLS master playlist with name master.m3u8 and keeps -publishing it repeatedly every after 30 segments i.e. every after 60s. -

-
-
http_persistent bool
-

Use persistent HTTP connections. Applicable only for HTTP output. -

-
-
timeout timeout
-

Set timeout for socket I/O operations. Applicable only for HTTP output. -

-
-
ignore_io_errors bool
-

Ignore IO errors during open, write and delete. Useful for long-duration runs with network output. -

-
-
headers headers
-

Set custom HTTP headers, can override built in default headers. Applicable only for HTTP output. -

-
- -
-
-
-

4.47 iamf

-

Immersive Audio Model and Formats (IAMF) muxer. -

-

IAMF is used to provide immersive audio content for presentation on a wide range -of devices in both streaming and offline applications. These applications -include internet audio streaming, multicasting/broadcasting services, file -download, gaming, communication, virtual and augmented reality, and others. In -these applications, audio may be played back on a wide range of devices, e.g., -headphones, mobile phones, tablets, TVs, sound bars, home theater systems, and -big screens. -

-

This format was promoted and desgined by Alliance for Open Media. -

-

For more information about this format, see https://aomedia.org/iamf/. -

-
-
-

4.48 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 -
- -
-
-

4.49 ilbc

-

Internet Low Bitrate Codec (iLBC) raw muxer. -

-

It accepts a single ‘ilbc’ audio stream. -

-
-
-

4.50 image2, image2pipe

-

Image file muxer. -

-

The ‘image2’ 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. -

-

The image muxer supports the .Y.U.V image file format. This format is -special in 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. -

-

The ‘image2pipe’ muxer accepts the same options as the ‘image2’ muxer, -but ignores the pattern verification and expansion, as it is supposed to write -to the command output rather than to an actual stored file. -

- -
-

4.50.1 Options

-
-
frame_pts bool
-

If set to 1, expand the filename with the packet PTS (presentation time stamp). -Default value is 0. -

-
-
start_number count
-

Start the sequence from the specified number. Default value is 1. -

-
-
update bool
-

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 bool
-

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

-
-
atomic_writing bool
-

Write output to a temporary file, which is renamed to target filename once -writing is completed. Default is disabled. -

-
-
protocol_opts options_list
-

Set protocol options as a :-separated list of key=value parameters. Values -containing the : special character must be escaped. -

-
- -
-
-

4.50.2 Examples

-
    -
  • 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. - -

    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"
-
    - -
  • Set the file name with current frame’s PTS: -
    -
    ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg
-
    - -
  • Publish contents of your desktop directly to a WebDAV server every second: -
    -
    ffmpeg -f x11grab -framerate 1 -i :0.0 -q:v 6 -update 1 -protocol_opts method=PUT http://example.com/desktop.jpg
-
    -
- -
-
-
-

4.51 ircam

-

Berkeley / IRCAM / CARL Sound Filesystem (BICSF) format muxer. -

-

The Berkeley/IRCAM/CARL Sound Format, developed in the 1980s, is a result of the -merging of several different earlier sound file formats and systems including -the csound system developed by Dr Gareth Loy at the Computer Audio Research Lab -(CARL) at UC San Diego, the IRCAM sound file system developed by Rob Gross and -Dan Timis at the Institut de Recherche et Coordination Acoustique / Musique in -Paris and the Berkeley Fast Filesystem. -

-

It was developed initially as part of the Berkeley/IRCAM/CARL Sound Filesystem, -a suite of programs designed to implement a filesystem for audio applications -running under Berkeley UNIX. It was particularly popular in academic music -research centres, and was used a number of times in the creation of early -computer-generated compositions. -

-

This muxer accepts a single audio stream containing PCM data. -

-
-
-

4.52 ivf

-

On2 IVF muxer. -

-

IVF was developed by On2 Technologies (formerly known as Duck -Corporation), to store internally developed codecs. -

-

This muxer accepts a single ‘vp8’, ‘vp9’, or ‘av1’ -video stream. -

-
-
-

4.53 jacosub

-

JACOsub subtitle format muxer. -

-

This muxer accepts a single ‘jacosub’ subtitles stream. -

-

For more information about the format, see -http://unicorn.us.com/jacosub/jscripts.html. -

-
-
-

4.54 kvag

-

Simon & Schuster Interactive VAG muxer. -

-

This custom VAG container is used by some Simon & Schuster Interactive -games such as "Real War", and "Real War: Rogue States". -

-

This muxer accepts a single ‘adpcm_ima_ssi’ audio stream. -

-
-
-

4.55 lc3

-

Bluetooth SIG Low Complexity Communication Codec audio (LC3), or -ETSI TS 103 634 Low Complexity Communication Codec plus (LC3plus). -

-

This muxer accepts a single ‘lc3’ audio stream. -

-
-
-

4.56 lrc

-

LRC lyrics file format muxer. -

-

LRC (short for LyRiCs) is a computer file format that synchronizes -song lyrics with an audio file, such as MP3, Vorbis, or MIDI. -

-

This muxer accepts a single ‘subrip’ or ‘text’ subtitles stream. -

- -
-

4.56.1 Metadata

-

The following metadata tags are converted to the format corresponding -metadata: -

-
-
title
-
album
-
artist
-
author
-
creator
-
encoder
-
encoder_version
-
- -

If ‘encoder_version’ is not explicitly set, it is automatically -set to the libavformat version. -

-
-
-
-

4.57 matroska

-

Matroska container muxer. -

-

This muxer implements the matroska and webm container specs. -

- -
-

4.57.1 Metadata

-

The recognized metadata settings in this muxer are: -

-
-
title
-

Set title name provided to a single track. This gets mapped to -the FileDescription element for a stream written as attachment. -

-
-
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
-
- -
-
-

4.57.2 Options

-
-
reserve_index_space size
-

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 size bytes -of space in the file header and then try to write the cues there when the muxing -finishes. If the reserved space does not suffice, no Cues will be written, the -file will be finalized and writing the trailer will return an error. -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. -

-
-
cues_to_front bool
-

If set, the muxer will write the index at the beginning of the file -by shifting the main data if necessary. This can be combined with -reserve_index_space in which case the data is only shifted if -the initially reserved space turns out to be insufficient. -

-

This option is ignored if the output is unseekable. -

-
-
cluster_size_limit size
-

Store at most the provided amount of bytes in a cluster. -

-

If not specified, the limit is set automatically to a sensible -hardcoded fixed value. -

-
-
cluster_time_limit duration
-

Store at most the provided number of milliseconds in a cluster. -

-

If not specified, the limit is set automatically to a sensible -hardcoded fixed value. -

-
-
dash bool
-

Create a WebM file conforming to WebM DASH specification. By default -it is set to false. -

-
-
dash_track_number index
-

Track number for the DASH stream. By default it is set to 1. -

-
-
live bool
-

Write files assuming it is a live stream. By default it is set to -false. -

-
-
allow_raw_vfw bool
-

Allow raw VFW mode. By default it is set to false. -

-
-
flipped_raw_rgb bool
-

If set to true, store positive height for raw RGB bitmaps, which indicates -bitmap is stored bottom-up. Note that this option does not flip the bitmap -which has to be done manually beforehand, e.g. by using the ‘vflip’ filter. -Default is false and indicates bitmap is stored top down. -

-
-
write_crc32 bool
-

Write a CRC32 element inside every Level 1 element. By default it is -set to true. This option is ignored for WebM. -

-
-
default_mode mode
-

Control how the FlagDefault of the output tracks will be set. -It influences which tracks players should play by default. The default mode -is ‘passthrough’. -

-
‘infer’
-

Every track with disposition default will have the FlagDefault set. -Additionally, for each type of track (audio, video or subtitle), if no track -with disposition default of this type exists, then the first track of this type -will be marked as default (if existing). This ensures that the default flag -is set in a sensible way even if the input originated from containers that -lack the concept of default tracks. -

-
‘infer_no_subs’
-

This mode is the same as infer except that if no subtitle track with -disposition default exists, no subtitle track will be marked as default. -

-
‘passthrough’
-

In this mode the FlagDefault is set if and only if the AV_DISPOSITION_DEFAULT -flag is set in the disposition of the corresponding stream. -

-
-
-
- -
-
-
-

4.58 md5

-

MD5 testing format. -

-

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

-

See also the hash and framemd5 muxers. -

- -
-

4.58.1 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
-
    - -
  • To print the MD5 hash to stdout: -
    -
    ffmpeg -i INPUT -f md5 -
-
    -
- -
-
-
-

4.59 microdvd

-

MicroDVD subtitle format muxer. -

-

This muxer accepts a single ‘microdvd’ subtitles stream. -

-
-
-

4.60 mmf

-

Synthetic music Mobile Application Format (SMAF) format muxer. -

-

SMAF is a music data format specified by Yamaha for portable -electronic devices, such as mobile phones and personal digital -assistants. -

-

This muxer accepts a single ‘adpcm_yamaha’ audio stream. -

-
-
-

4.61 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
-
- -
-
-

4.62 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’. -

- -
-

4.62.1 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 hexadecimal value between 0x01 and 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 PMTs. Default is 0x1000, minimum is 0x0020, -maximum is 0x1ffa. This option has no effect in m2ts mode where the PMT -PID is fixed 0x0100. -

-
-
mpegts_start_pid integer
-

Set the first PID for elementary streams. Default is 0x0100, minimum is -0x0020, maximum is 0x1ffa. This option has no effect in m2ts mode -where the elementary stream PIDs are fixed. -

-
-
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. -

-
‘nit’
-

Emit NIT table. -

-
‘omit_rai’
-

Disable writing of random access indicator. -

-
- -
-
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. Default is --1 which means that the PCR interval will be determined automatically: -20 ms is used for CBR streams, the highest multiple of the frame duration which -is less than 100 ms is used for VBR streams. -

-
-
pat_period duration
-

Maximum time in seconds between PAT/PMT tables. Default is 0.1. -

-
-
sdt_period duration
-

Maximum time in seconds between SDT tables. Default is 0.5. -

-
-
nit_period duration
-

Maximum time in seconds between NIT tables. Default is 0.5. -

-
-
tables_version integer
-

Set PAT, PMT, SDT and NIT 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
-...
-
-
-
- -
-
-

4.62.2 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
-
- -
-
-
-

4.63 mxf, mxf_d10, mxf_opatom

- -

MXF muxer. -

- -
-

4.63.1 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 and mxf_opatom but not for mxf_d10 -

-
- -
-
-
-

4.64 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 -
-
- -
-
-

4.65 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, -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
-
- -
-
-

4.66 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. -

-
-
- -
-
-

4.67 rcwt

- -

RCWT (Raw Captions With Time) is a format native to ccextractor, a commonly -used open source tool for processing 608/708 Closed Captions (CC) sources. -It can be used to archive the original extracted CC bitstream and to produce -a source file for later processing or conversion. The format allows -for interoperability between ccextractor and FFmpeg, is simple to parse, -and can be used to create a backup of the CC presentation. -

-

This muxer implements the specification as of March 2024, which has -been stable and unchanged since April 2014. -

-

This muxer will have some nuances from the way that ccextractor muxes RCWT. -No compatibility issues when processing the output with ccextractor -have been observed as a result of this so far, but mileage may vary -and outputs will not be a bit-exact match. -

-

A free specification of RCWT can be found here: -https://github.com/CCExtractor/ccextractor/blob/master/docs/BINARY_FILE_FORMAT.TXT -

- -
-

4.67.1 Examples

- -
    -
  • Extract Closed Captions to RCWT using lavfi: -
    -
    ffmpeg -f lavfi -i "movie=INPUT.mkv[out+subcc]" -map 0:s:0 -c:s copy -f rcwt CC.rcwt.bin
-
    -
- -
-
-
-

4.68 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. -

- -
-

4.68.1 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. -

-
-
min_seg_duration time
-

Set minimum segment duration to time, the value must be a duration -specification. This prevents the muxer ending segments at a duration below -this value. Only effective with segment_time. Default value is "0". -

-
-
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 beginning 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. -

-
- -

Make sure to require a closed GOP when encoding and to set the GOP -size to fit your segment time constraint. -

-
-
-

4.68.2 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 hevc -flags +cgop -g 60 -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
-
    -
- -
-
-
-

4.69 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). -

-
-
- -
-
-

4.70 streamhash

- -

Per stream hash testing format. -

-

This muxer computes and prints a cryptographic hash of all the input frames, -on a per-stream basis. 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 one line per stream of the form: -streamindex,streamtype,algo=hash, where -streamindex is the index of the mapped stream, streamtype is a -single character indicating the type of stream, 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. -

-
-
- - -
-

4.70.1 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 streamhash out.sha256
-
- -

To print an MD5 hash to stdout use the command: -

-
ffmpeg -i INPUT -f streamhash -hash md5 -
-
- -

See also the hash and framehash muxers. -

-
-
-
-

4.71 tee

- -

The tee muxer can be used to write the same data to several outputs, such as files or streams. -It can be used, for example, to stream a video over a network and save it to disk at the same time. -

-

It is different from specifying several outputs to the ffmpeg -command-line tool. With the tee muxer, the audio and video data will be encoded only once. -With conventional multiple outputs, multiple encoding operations in parallel are initiated, -which can be a very expensive process. The tee muxer is not useful when using the libavformat API -directly because it is then possible to feed the same packets to several muxers directly. -

-

Since the tee muxer does not represent any particular output format, ffmpeg cannot auto-select -output streams. So all streams intended for output must be specified using -map. See -the examples below. -

-

Some encoders may need different options depending on the output format; -the auto-detection of this can not work with the tee muxer, so they need to be explicitly specified. -The main example is the global_header flag. -

-

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, those must be -escaped (see the "Quoting and escaping" -section in the ffmpeg-utils(1) manual). -

- -
-

4.71.1 Options

- -
-
use_fifo bool
-

If set to 1, slave outputs will be processed in separate threads using the 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. -

-
-
- -

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. Required if it cannot be guessed from the -output URL. -

-
-
bsfs[/spec]
-

Specify a list of bitstream filters to apply to the specified -output. -

-

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. This will cause that output operation -to fail if the output contains streams to which the bitstream filter cannot -be applied e.g. h264_mp4toannexb being applied to an output containing an audio stream. -

-

Options for a bitstream filter must be specified in the form of opt=value. -

-

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

-
-
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. -

-
-
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 mapped streams. This will cause that output operation to fail -if the output format does not accept all mapped 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. -

-
- -
-
-

4.71.2 Examples

- -
    -
  • Encode something and both archive it in a WebM file and stream it -as MPEG-TS over UDP: -
    -
    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=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
-
    - -
  • As above, 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=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
-
    -
- -
-
-
-

4.72 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. -

- -
-

4.72.1 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). -

-
- -
-
-

4.72.2 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
-
- -
-
-
-

4.73 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: -

- - - -
-

4.73.1 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. -

-
-
- -
-
-

4.73.2 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
-
- -
-
-
-
-

5 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 nanoseconds. - -

    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
-
- - -
-
-

6 See Also

- -

ffmpeg, ffplay, ffprobe, -libavformat -

- -
-
-

7 Authors

- -

The FFmpeg developers. -

-

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

-

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

- -
-
-

- This document was generated using makeinfo. -

-
- -