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FFMPEG(1) FFMPEG(1)

NAME
ffmpeg - ffmpeg media converter

SYNOPSIS
ffmpeg [global_options] {[input_file_options] -i input_url} ... {[out-
put_file_options] output_url} ...

DESCRIPTION
ffmpeg is a universal media converter. It can read a wide variety of inputs
- including live grabbing/recording devices - filter, and transcode them
into a plethora of output formats.

ffmpeg reads from an arbitrary number of inputs (which can be regular
files, pipes, network streams, grabbing devices, etc.), specified by the
"-i" option, and writes to an arbitrary number of outputs, which are speci-
fied by a plain output url. Anything found on the command line which cannot
be interpreted as an option is considered to be an output url.

Each input or output can, in principle, contain any number of elementary
streams of different types (video/audio/subtitle/attachment/data), though
the allowed stream counts and/or types may be limited by the container for-
mat. Selecting which streams from which inputs will go into which output is
either done automatically or with the "-map" option (see the Stream selec-
tion chapter).

To refer to inputs/outputs in options, you must use their indices
(0-based). E.g. the first input is 0, the second is 1, etc. Similarly,
streams within an input/output are referred to by their indices. E.g. "2:3"
refers to the fourth stream in the third input or output. Also see the
Stream specifiers chapter.

As a general rule, options are applied to the next specified file. There-
fore, order is important, and you can have the same option on the command
line multiple times. Each occurrence is then applied to the next input or
output file. Exceptions from this rule are the global options (e.g. ver-
bosity level), which should be specified first.

Do not mix input and output files -- first specify all input files, then
all output files. Also do not mix options which belong to different files.
All options apply ONLY to the next input or output file and are reset be-
tween files.

Some simple examples follow.

* Convert an input media file to a different format, by re-encoding media
streams:

ffmpeg -i input.avi output.mp4

* Set the video bitrate of the output file to 64 kbit/s:

ffmpeg -i input.avi -b:v 64k -bufsize 64k output.mp4

* Force the frame rate of the output file to 24 fps:

ffmpeg -i input.avi -r 24 output.mp4

* Force the frame rate of the input file (valid for raw formats only) to
1 fps and the frame rate of the output file to 24 fps:

ffmpeg -r 1 -i input.m2v -r 24 output.mp4

The format option may be needed for raw input files.

DETAILED DESCRIPTION
ffmpeg builds a transcoding pipeline out of the components listed below.
The program's operation then consists of input data chunks flowing from the
sources down the pipes towards the sinks, while being transformed by the
components they encounter along the way.

The following kinds of components are available:

* Demuxers (short for "demultiplexers") read an input source in order to
extract

* global properties such as metadata or chapters;

* list of input elementary streams and their properties

One demuxer instance is created for each -i option, and sends encoded
packets to decoders or muxers.

In other literature, demuxers are sometimes called splitters, because
their main function is splitting a file into elementary streams (though
some files only contain one elementary stream).

A schematic representation of a demuxer looks like this:

aaaaaaaaaaaa~aaaaaaaaaaaaaaaaaaaaaaaa
a demuxer a a packets for stream 0
aaaaaaaaaaaa! elementary stream 0 aaaaaaaaaaaaaaaaaaaaaaaao
a a a
a global aaaaaaaaaaaaaaaaaaaaaaaaax
apropertiesa a packets for stream 1
a and a elementary stream 1 aaaaaaaaaaaaaaaaaaaaaaaao
a metadata a a
a aaaaaaaaaaaaaaaaaaaaaaaaax
a a a
a a ........... a
a a a
a aaaaaaaaaaaaaaaaaaaaaaaaax
a a a packets for stream N
a a elementary stream N aaaaaaaaaaaaaaaaaaaaaaaao
a a a
aaaaaaaaaaaa'aaaaaaaaaaaaaaaaaaaaaaaa
a^2
a
a read from file, network stream,
a grabbing device, etc.
a

* Decoders receive encoded (compressed) packets for an audio, video, or
subtitle elementary stream, and decode them into raw frames (arrays of
pixels for video, PCM for audio). A decoder is typically associated
with (and receives its input from) an elementary stream in a demuxer,
but sometimes may also exist on its own (see Loopback decoders).

A schematic representation of a decoder looks like this:

aaaaaaaaaaa
packets a a raw frames
aaaaaaaaaaoa decoder aaaaaaaaaaaaaao
a a
aaaaaaaaaaa

* Filtergraphs process and transform raw audio or video frames. A filter-
graph consists of one or more individual filters linked into a graph.
Filtergraphs come in two flavors - simple and complex, configured with
the -filter and -filter_complex options, respectively.

A simple filtergraph is associated with an output elementary stream; it
receives the input to be filtered from a decoder and sends filtered
output to that output stream's encoder.

A simple video filtergraph that performs deinterlacing (using the
"yadif" deinterlacer) followed by resizing (using the "scale" filter)
can look like this:

aaaaaaaaaaaaaaaaaaaaaaaaaa
a simple filtergraph a
frames from aaaaaaaaaaaaaaaaaaaaaaaaaa! frames for
a decoder a aaaaaaaaa aaaaaaaaa a an encoder
aaaaaaaaaaaaaoaaaoa yadif aaaoa scale aaaoaaaaaaaaaaaaaao
a aaaaaaaaa aaaaaaaaa a
aaaaaaaaaaaaaaaaaaaaaaaaaa

A complex filtergraph is standalone and not associated with any spe-
cific stream. It may have multiple (or zero) inputs, potentially of
different types (audio or video), each of which receiving data either
from a decoder or another complex filtergraph's output. It also has one
or more outputs that feed either an encoder or another complex filter-
graph's input.

The following example diagram represents a complex filtergraph with 3
inputs and 2 outputs (all video):

aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
a complex filtergraph a
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa!
frames aaaaaaaaa aaaaaaaaaaa aaaaaaaaaaa aaaaaaaaaax frames
aaaaaaaaaaoainput 0aaaoa overlay aaaaaaaoa overlay aaaoaoutput 0aaaaaaaaaao
aaaaaaaaa a a a a aaaaaaaaaax
frames aaaaaaaaaaao_a a aaoa a a
aaaaaaaaaaoainput 1aa aaaaaaaaaaa a aaaaaaaaaaa a
aaaaaaaaa a _ a
frames aaaaaaaaa aaaaaaa aaaaaaa~aa aaaaaaaaaax frames
aaaaaaaaaaoainput 2aaoascaleaaoasplitaaaaaaaaaaaaaaaaaoaoutput 1aaaaaaaaaao
aaaaaaaaa aaaaaaa aaaaaaa aaaaaaaaaax
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

Frames from second input are overlaid over those from the first. Frames
from the third input are rescaled, then the duplicated into two identi-
cal streams. One of them is overlaid over the combined first two in-
puts, with the result exposed as the filtergraph's first output. The
other duplicate ends up being the filtergraph's second output.

* Encoders receive raw audio, video, or subtitle frames and encode them
into encoded packets. The encoding (compression) process is typically
lossy - it degrades stream quality to make the output smaller; some en-
coders are lossless, but at the cost of much higher output size. A
video or audio encoder receives its input from some filtergraph's out-
put, subtitle encoders receive input from a decoder (since subtitle
filtering is not supported yet). Every encoder is associated with some
muxer's output elementary stream and sends its output to that muxer.

A schematic representation of an encoder looks like this:

aaaaaaaaaaa
raw frames a a packets
aaaaaaaaaaaaaoa encoder aaaaaaaaaaao
a a
aaaaaaaaaaa

* Muxers (short for "multiplexers") receive encoded packets for their el-
ementary streams from encoders (the transcoding path) or directly from
demuxers (the streamcopy path), interleave them (when there is more
than one elementary stream), and write the resulting bytes into the
output file (or pipe, network stream, etc.).

A schematic representation of a muxer looks like this:

aaaaaaaaaaaaaaaaaaaaaaaa~aaaaaaaaaaaa
packets for stream 0 a a muxer a
aaaaaaaaaaaaaaaaaaaaaaaoa elementary stream 0 aaaaaaaaaaaaa!
a a a
aaaaaaaaaaaaaaaaaaaaaaaax global a
packets for stream 1 a aproperties a
aaaaaaaaaaaaaaaaaaaaaaaoa elementary stream 1 a and a
a a metadata a
aaaaaaaaaaaaaaaaaaaaaaaax a
a a a
a ........... a a
a a a
aaaaaaaaaaaaaaaaaaaaaaaax a
packets for stream N a a a
aaaaaaaaaaaaaaaaaaaaaaaoa elementary stream N a a
a a a
aaaaaaaaaaaaaaaaaaaaaaaa'aaaaaa~aaaaaa
a
write to file, network stream, a
grabbing device, etc. a
a
a1/4

Streamcopy
The simplest pipeline in ffmpeg is single-stream streamcopy, that is copy-
ing one input elementary stream's packets without decoding, filtering, or
encoding them. As an example, consider an input file called INPUT.mkv with
3 elementary streams, from which we take the second and write it to file
OUTPUT.mp4. A schematic representation of such a pipeline looks like this:

aaaaaaaaaaaa~aaaaaaaaaaaaaaaaaaaaaa
a demuxer a a unused
aaaaaaaaaaaa! elementary stream 0 aaaaaaaaaa^3
a a a
aINPUT.mkv aaaaaaaaaaaaaaaaaaaaaaax aaaaaaaaaaaaaaaaaaaaaaaa~aaaaaaaaaaaa
a a a packets a a muxer a
a a elementary stream 1 aaaaaaaaaaaoa elementary stream 0 aaaaaaaaaaaaa!
a a a a aOUTPUT.mp4 a
a aaaaaaaaaaaaaaaaaaaaaaax aaaaaaaaaaaaaaaaaaaaaaaa'aaaaaaaaaaaa
a a a unused
a a elementary stream 2 aaaaaaaaaa^3
a a a
aaaaaaaaaaaa'aaaaaaaaaaaaaaaaaaaaaa

The above pipeline can be constructed with the following commandline:

ffmpeg -i INPUT.mkv -map 0:1 -c copy OUTPUT.mp4

In this commandline

* there is a single input INPUT.mkv;

* there are no input options for this input;

* there is a single output OUTPUT.mp4;

* there are two output options for this output:

* "-map 0:1" selects the input stream to be used - from input with
index 0 (i.e. the first one) the stream with index 1 (i.e. the sec-
ond one);

* "-c copy" selects the "copy" encoder, i.e. streamcopy with no de-
coding or encoding.

Streamcopy is useful for changing the elementary stream count, container
format, or modifying container-level metadata. Since there is no decoding
or encoding, it is very fast and there is no quality loss. However, it
might not work in some cases because of a variety of factors (e.g. certain
information required by the target container is not available in the
source). Applying filters is obviously also impossible, since filters work
on decoded frames.

More complex streamcopy scenarios can be constructed - e.g. combining
streams from two input files into a single output:

aaaaaaaaaaaa~aaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaaa~aaaaaaaaaaaa
a demuxer 0a a packets a a muxer a
aaaaaaaaaaaa!elementary stream 0 aaaaaaaaaaoaelementary stream 0 aaaaaaaaaaaaa!
aINPUT0.mkva a a aOUTPUT.mp4 a
aaaaaaaaaaaa'aaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaaax a
aaaaaaaaaaaa~aaaaaaaaaaaaaaaaaaaaa a a a
a demuxer 1a a packets aelementary stream 1 a a
aaaaaaaaaaaa!elementary stream 0 aaaaaaaaaaoa a a
aINPUT1.aaca a aaaaaaaaaaaaaaaaaaaaaa'aaaaaaaaaaaa
aaaaaaaaaaaa'aaaaaaaaaaaaaaaaaaaaa

that can be built by the commandline

ffmpeg -i INPUT0.mkv -i INPUT1.aac -map 0:0 -map 1:0 -c copy OUTPUT.mp4

The output -map option is used twice here, creating two streams in the out-
put file - one fed by the first input and one by the second. The single in-
stance of the -c option selects streamcopy for both of those streams. You
could also use multiple instances of this option together with Stream spec-
ifiers to apply different values to each stream, as will be demonstrated in
following sections.

A converse scenario is splitting multiple streams from a single input into
multiple outputs:

aaaaaaaaaaaa~aaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaa~aaaaaaaaaaaa
a demuxer a a packets a a muxer 0 a
aaaaaaaaaaaa! elementary stream 0 aaaaaaaaaaaoaelementary stream 0aaaaaaaaaaaaa!
a a a a aOUTPUT0.mp4a
aINPUT.mkv aaaaaaaaaaaaaaaaaaaaaaax aaaaaaaaaaaaaaaaaaaaa'aaaaaaaaaaaa
a a a packets aaaaaaaaaaaaaaaaaaaaa~aaaaaaaaaaaa
a a elementary stream 1 aaaaaaaaaaaoa a muxer 1 a
a a a aelementary stream 0aaaaaaaaaaaaa!
aaaaaaaaaaaa'aaaaaaaaaaaaaaaaaaaaaa a aOUTPUT1.mp4a
aaaaaaaaaaaaaaaaaaaaa'aaaaaaaaaaaa

built with

ffmpeg -i INPUT.mkv -map 0:0 -c copy OUTPUT0.mp4 -map 0:1 -c copy OUTPUT1.mp4

Note how a separate instance of the -c option is needed for every output
file even though their values are the same. This is because non-global op-
tions (which is most of them) only apply in the context of the file before
which they are placed.

These examples can of course be further generalized into arbitrary remap-
pings of any number of inputs into any number of outputs.

Transcoding
Transcoding is the process of decoding a stream and then encoding it again.
Since encoding tends to be computationally expensive and in most cases de-
grades the stream quality (i.e. it is lossy), you should only transcode
when you need to and perform streamcopy otherwise. Typical reasons to
transcode are:

* applying filters - e.g. resizing, deinterlacing, or overlaying video;
resampling or mixing audio;

* you want to feed the stream to something that cannot decode the origi-
nal codec.

Note that ffmpeg will transcode all audio, video, and subtitle streams un-
less you specify -c copy for them.

Consider an example pipeline that reads an input file with one audio and
one video stream, transcodes the video and copies the audio into a single
output file. This can be schematically represented as follows

aaaaaaaaaaaa~aaaaaaaaaaaaaaaaaaaaaa
a demuxer a a audio packets
aaaaaaaaaaaa! stream 0 (audio) aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa(R)
a a a a
aINPUT.mkv aaaaaaaaaaaaaaaaaaaaaaax video aaaaaaaaaaa raw a
a a a packets a video a video frames a
a a stream 1 (video) aaaaaaaaaaaoa decoder aaaaaaaaaaaaaaaa(R) a
a a a a a a a
aaaaaaaaaaaa'aaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaa a a
a1/4 a1/4
a a
aaaaaaaaaaaa~aaaaaaaaaaaaaaaaaaaaaa video aaaaaaaaaaa a a
a muxer a a packets a video a a a_
aaaaaaaaaaaa! stream 0 (video) aaaaaaaaaaaax encoder aaaaaaaaaaaaaaaa a
a a a a(libx264)a a
aOUTPUT.mp4aaaaaaaaaaaaaaaaaaaaaaax aaaaaaaaaaa a
a a a a_
a a stream 1 (audio) aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
a a a
aaaaaaaaaaaa'aaaaaaaaaaaaaaaaaaaaaa

and implemented with the following commandline:

ffmpeg -i INPUT.mkv -map 0:v -map 0:a -c:v libx264 -c:a copy OUTPUT.mp4

Note how it uses stream specifiers ":v" and ":a" to select input streams
and apply different values of the -c option to them; see the Stream speci-
fiers section for more details.

Filtering
When transcoding, audio and video streams can be filtered before encoding,
with either a simple or complex filtergraph.

Simple filtergraphs

Simple filtergraphs are those that have exactly one input and output, both
of the same type (audio or video). They are configured with the per-stream
-filter option (with -vf and -af aliases for -filter:v (video) and -fil-
ter:a (audio) respectively). Note that simple filtergraphs are tied to
their output stream, so e.g. if you have multiple audio streams, -af will
create a separate filtergraph for each one.

Taking the transcoding example from above, adding filtering (and omitting
audio, for clarity) makes it look like this:

aaaaaaaaaaaa~aaaaaaaaaaaaaaaa
a demuxer a a aaaaaaaaaaa
aaaaaaaaaaaa! video stream a packets a video a frames
aINPUT.mkv a aaaaaaaaaaaoa decoder aaaaaaaoaaaa(R)
a a a aaaaaaaaaaa a
aaaaaaaaaaaa'aaaaaaaaaaaaaaaa _
aaaaaaaaaaaaaaaaaaaaaaaaa
a aaaaaaaaaaaaaaaaaaaaaaaaaa
a a simple filtergraph a
a aaaaaaaaaaaaaaaaaaaaaaaaaa!
a a aaaaaaaaa aaaaaaaaa a
a<degree>aaaoaaaoa yadif aaaoa scale aaaoaa(R)
a aaaaaaaaa aaaaaaaaa aa
aaaaaaaaaaaaaaaaaaaaaaaaaaa
a
a
aaaaaaaaaaaa~aaaaaaaaaaaaaaaa video aaaaaaaaaaa a
a muxer a a packets a video a a _
aaaaaaaaaaaa! video stream aaaaaaaaaaaax encoder aaaaaaaaaaaaaaaaa
aOUTPUT.mp4a a a a
a a a aaaaaaaaaaa
aaaaaaaaaaaa'aaaaaaaaaaaaaaaa

Complex filtergraphs

Complex filtergraphs are those which cannot be described as simply a linear
processing chain applied to one stream. This is the case, for example, when
the graph has more than one input and/or output, or when output stream type
is different from input. Complex filtergraphs are configured with the -fil-
ter_complex option. Note that this option is global, since a complex fil-
tergraph, by its nature, cannot be unambiguously associated with a single
stream or file. Each instance of -filter_complex creates a new complex fil-
tergraph, and there can be any number of them.

A trivial example of a complex filtergraph is the "overlay" filter, which
has two video inputs and one video output, containing one video overlaid on
top of the other. Its audio counterpart is the "amix" filter.

Loopback decoders
While decoders are normally associated with demuxer streams, it is also
possible to create "loopback" decoders that decode the output from some en-
coder and allow it to be fed back to complex filtergraphs. This is done
with the "-dec" directive, which takes as a parameter the index of the out-
put stream that should be decoded. Every such directive creates a new loop-
back decoder, indexed with successive integers starting at zero. These in-
dices should then be used to refer to loopback decoders in complex filter-
graph link labels, as described in the documentation for -filter_complex.

Decoding AVOptions can be passed to loopback decoders by placing them be-
fore "-dec", analogously to input/output options.

E.g. the following example:

ffmpeg -i INPUT \
-map 0:v:0 -c:v libx264 -crf 45 -f null - \
-threads 3 -dec 0:0 \
-filter_complex '[0:v][dec:0]hstack[stack]' \
-map '[stack]' -c:v ffv1 OUTPUT

reads an input video and

* (line 2) encodes it with "libx264" at low quality;

* (line 3) decodes this encoded stream using 3 threads;

* (line 4) places decoded video side by side with the original input
video;

* (line 5) combined video is then losslessly encoded and written into
OUTPUT.

Such a transcoding pipeline can be represented with the following diagram:

aaaaaaaaaaaa~aaaaaaaaaaaaaaaa
a demuxer a a aaaaaaaaaaa aaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaaa
aaaaaaaaaaaa! video stream a a video a a video a a null muxer a
a INPUT a aaaaoa decoder aaaa~aaaaaaaaaoa encoder aaa~aaoa(discards its input)a
a a a aaaaaaaaaaa a a(libx264)a a aaaaaaaaaaaaaaaaaaaaaa
aaaaaaaaaaaa'aaaaaaaaaaaaaaaa _ aaaaaaaaaaa a
aaaaaaaaaaaa aaaaaaaaaaa a
a aloopback a a _
a aaaaaaaaaaaaaax decoder aaaaaaaaa
a a aaaaaaaaaaa
a a
a a
a a aaaaaaaaaaaaaaaaaaaaa
a a acomplex filtergrapha
a a aaaaaaaaaaaaaaaaaaaaa!
a a a aaaaaaaaaaaaaaa a
a<degree>aa<<aaoaaaoa hstack aaaoaa(R)
a<degree>aaoaaaoa a aa
a aaaaaaaaaaaaaaa aa
aaaaaaaaaaaaaaaaaaaaaa
a
aaaaaaaaaaaa~aaaaaaaaaaaaaaaa aaaaaaaaaaa a
a muxer a a a video a a _
aaaaaaaaaaaa! video stream aaaax encoder aaaaaaaaaaaaaaaaaaaa
a OUTPUT a a a (ffv1) a
a a a aaaaaaaaaaa
aaaaaaaaaaaa'aaaaaaaaaaaaaaaa

STREAM SELECTION
ffmpeg provides the "-map" option for manual control of stream selection in
each output file. Users can skip "-map" and let ffmpeg perform automatic
stream selection as described below. The "-vn / -an / -sn / -dn" options
can be used to skip inclusion of video, audio, subtitle and data streams
respectively, whether manually mapped or automatically selected, except for
those streams which are outputs of complex filtergraphs.

Description
The sub-sections that follow describe the various rules that are involved
in stream selection. The examples that follow next show how these rules
are applied in practice.

While every effort is made to accurately reflect the behavior of the pro-
gram, FFmpeg is under continuous development and the code may have changed
since the time of this writing.

Automatic stream selection

In the absence of any map options for a particular output file, ffmpeg in-
spects the output format to check which type of streams can be included in
it, viz. video, audio and/or subtitles. For each acceptable stream type,
ffmpeg will pick one stream, when available, from among all the inputs.

It will select that stream based upon the following criteria:

* for video, it is the stream with the highest resolution,

* for audio, it is the stream with the most channels,

* for subtitles, it is the first subtitle stream found but there's a
caveat. The output format's default subtitle encoder can be either
text-based or image-based, and only a subtitle stream of the same type
will be chosen.

In the case where several streams of the same type rate equally, the stream
with the lowest index is chosen.

Data or attachment streams are not automatically selected and can only be
included using "-map".

Manual stream selection

When "-map" is used, only user-mapped streams are included in that output
file, with one possible exception for filtergraph outputs described below.

Complex filtergraphs

If there are any complex filtergraph output streams with unlabeled pads,
they will be added to the first output file. This will lead to a fatal er-
ror if the stream type is not supported by the output format. In the ab-
sence of the map option, the inclusion of these streams leads to the auto-
matic stream selection of their types being skipped. If map options are
present, these filtergraph streams are included in addition to the mapped
streams.

Complex filtergraph output streams with labeled pads must be mapped once
and exactly once.

Stream handling

Stream handling is independent of stream selection, with an exception for
subtitles described below. Stream handling is set via the "-codec" option
addressed to streams within a specific output file. In particular, codec
options are applied by ffmpeg after the stream selection process and thus
do not influence the latter. If no "-codec" option is specified for a
stream type, ffmpeg will select the default encoder registered by the out-
put file muxer.

An exception exists for subtitles. If a subtitle encoder is specified for
an output file, the first subtitle stream found of any type, text or image,
will be included. ffmpeg does not validate if the specified encoder can
convert the selected stream or if the converted stream is acceptable within
the output format. This applies generally as well: when the user sets an
encoder manually, the stream selection process cannot check if the encoded
stream can be muxed into the output file. If it cannot, ffmpeg will abort
and all output files will fail to be processed.

Examples
The following examples illustrate the behavior, quirks and limitations of
ffmpeg's stream selection methods.

They assume the following three input files.

input file 'A.avi'
stream 0: video 640x360
stream 1: audio 2 channels

input file 'B.mp4'
stream 0: video 1920x1080
stream 1: audio 2 channels
stream 2: subtitles (text)
stream 3: audio 5.1 channels
stream 4: subtitles (text)

input file 'C.mkv'
stream 0: video 1280x720
stream 1: audio 2 channels
stream 2: subtitles (image)

Example: automatic stream selection

ffmpeg -i A.avi -i B.mp4 out1.mkv out2.wav -map 1:a -c:a copy out3.mov

There are three output files specified, and for the first two, no "-map"
options are set, so ffmpeg will select streams for these two files automat-
ically.

out1.mkv is a Matroska container file and accepts video, audio and subtitle
streams, so ffmpeg will try to select one of each type.For video, it will
select "stream 0" from B.mp4, which has the highest resolution among all
the input video streams.For audio, it will select "stream 3" from B.mp4,
since it has the greatest number of channels.For subtitles, it will select
"stream 2" from B.mp4, which is the first subtitle stream from among A.avi
and B.mp4.

out2.wav accepts only audio streams, so only "stream 3" from B.mp4 is se-
lected.

For out3.mov, since a "-map" option is set, no automatic stream selection
will occur. The "-map 1:a" option will select all audio streams from the
second input B.mp4. No other streams will be included in this output file.

For the first two outputs, all included streams will be transcoded. The en-
coders chosen will be the default ones registered by each output format,
which may not match the codec of the selected input streams.

For the third output, codec option for audio streams has been set to
"copy", so no decoding-filtering-encoding operations will occur, or can oc-
cur. Packets of selected streams shall be conveyed from the input file and
muxed within the output file.

Example: automatic subtitles selection

ffmpeg -i C.mkv out1.mkv -c:s dvdsub -an out2.mkv

Although out1.mkv is a Matroska container file which accepts subtitle
streams, only a video and audio stream shall be selected. The subtitle
stream of C.mkv is image-based and the default subtitle encoder of the Ma-
troska muxer is text-based, so a transcode operation for the subtitles is
expected to fail and hence the stream isn't selected. However, in out2.mkv,
a subtitle encoder is specified in the command and so, the subtitle stream
is selected, in addition to the video stream. The presence of "-an" dis-
ables audio stream selection for out2.mkv.

Example: unlabeled filtergraph outputs

ffmpeg -i A.avi -i C.mkv -i B.mp4 -filter_complex "overlay" out1.mp4 out2.srt

A filtergraph is setup here using the "-filter_complex" option and consists
of a single video filter. The "overlay" filter requires exactly two video
inputs, but none are specified, so the first two available video streams
are used, those of A.avi and C.mkv. The output pad of the filter has no la-
bel and so is sent to the first output file out1.mp4. Due to this, auto-
matic selection of the video stream is skipped, which would have selected
the stream in B.mp4. The audio stream with most channels viz. "stream 3" in
B.mp4, is chosen automatically. No subtitle stream is chosen however, since
the MP4 format has no default subtitle encoder registered, and the user
hasn't specified a subtitle encoder.

The 2nd output file, out2.srt, only accepts text-based subtitle streams.
So, even though the first subtitle stream available belongs to C.mkv, it is
image-based and hence skipped. The selected stream, "stream 2" in B.mp4,
is the first text-based subtitle stream.

Example: labeled filtergraph outputs

ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0[outv];overlay;aresample" \
-map '[outv]' -an out1.mp4 \
out2.mkv \
-map '[outv]' -map 1:a:0 out3.mkv

The above command will fail, as the output pad labelled "[outv]" has been
mapped twice. None of the output files shall be processed.

ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0[outv];overlay;aresample" \
-an out1.mp4 \
out2.mkv \
-map 1:a:0 out3.mkv

This command above will also fail as the hue filter output has a label,
"[outv]", and hasn't been mapped anywhere.

The command should be modified as follows,

ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0,split=2[outv1][outv2];overlay;aresample" \
-map '[outv1]' -an out1.mp4 \
out2.mkv \
-map '[outv2]' -map 1:a:0 out3.mkv

The video stream from B.mp4 is sent to the hue filter, whose output is
cloned once using the split filter, and both outputs labelled. Then a copy
each is mapped to the first and third output files.

The overlay filter, requiring two video inputs, uses the first two unused
video streams. Those are the streams from A.avi and C.mkv. The overlay out-
put isn't labelled, so it is sent to the first output file out1.mp4, re-
gardless of the presence of the "-map" option.

The aresample filter is sent the first unused audio stream, that of A.avi.
Since this filter output is also unlabelled, it too is mapped to the first
output file. The presence of "-an" only suppresses automatic or manual
stream selection of audio streams, not outputs sent from filtergraphs. Both
these mapped streams shall be ordered before the mapped stream in out1.mp4.

The video, audio and subtitle streams mapped to "out2.mkv" are entirely de-
termined by automatic stream selection.

out3.mkv consists of the cloned video output from the hue filter and the
first audio stream from B.mp4.

OPTIONS
All the numerical options, if not specified otherwise, accept a string rep-
resenting a number as input, which may be followed by one of the SI unit
prefixes, for example: 'K', 'M', or 'G'.

If 'i' is appended to the SI unit prefix, the complete prefix will be in-
terpreted as a unit prefix for binary multiples, which are based on powers
of 1024 instead of powers of 1000. Appending 'B' to the SI unit prefix mul-
tiplies the value by 8. This allows using, for example: 'KB', 'MiB', 'G'
and 'B' as number suffixes.

Options which do not take arguments are boolean options, and set the corre-
sponding value to true. They can be set to false by prefixing the option
name with "no". For example using "-nofoo" will set the boolean option with
name "foo" to false.

Options that take arguments support a special syntax where the argument
given on the command line is interpreted as a path to the file from which
the actual argument value is loaded. To use this feature, add a forward
slash '/' immediately before the option name (after the leading dash). E.g.

ffmpeg -i INPUT -/filter:v filter.script OUTPUT

will load a filtergraph description from the file named filter.script.

Stream specifiers
Some options are applied per-stream, e.g. bitrate or codec. Stream speci-
fiers are used to precisely specify which stream(s) a given option belongs
to.

A stream specifier is a string generally appended to the option name and
separated from it by a colon. E.g. "-codec:a:1 ac3" contains the "a:1"
stream specifier, which matches the second audio stream. Therefore, it
would select the ac3 codec for the second audio stream.

A stream specifier can match several streams, so that the option is applied
to all of them. E.g. the stream specifier in "-b:a 128k" matches all audio
streams.

An empty stream specifier matches all streams. For example, "-codec copy"
or "-codec: copy" would copy all the streams without reencoding.

Possible forms of stream specifiers are:

stream_index
Matches the stream with this index. E.g. "-threads:1 4" would set the
thread count for the second stream to 4. If stream_index is used as an
additional stream specifier (see below), then it selects stream number
stream_index from the matching streams. Stream numbering is based on
the order of the streams as detected by libavformat except when a
stream group specifier or program ID is also specified. In this case it
is based on the ordering of the streams in the group or program.

stream_type[:additional_stream_specifier]
stream_type is one of following: 'v' or 'V' for video, 'a' for audio,
's' for subtitle, 'd' for data, and 't' for attachments. 'v' matches
all video streams, 'V' only matches video streams which are not at-
tached pictures, video thumbnails or cover arts. If addi-
tional_stream_specifier is used, then it matches streams which both
have this type and match the additional_stream_specifier. Otherwise, it
matches all streams of the specified type.

g:group_specifier[:additional_stream_specifier]
Matches streams which are in the group with the specifier group_speci-
fier. if additional_stream_specifier is used, then it matches streams
which both are part of the group and match the additional_stream_speci-
fier. group_specifier may be one of the following:

group_index
Match the stream with this group index.

#group_id or i:group_id
Match the stream with this group id.

p:program_id[:additional_stream_specifier]
Matches streams which are in the program with the id program_id. If ad-
ditional_stream_specifier is used, then it matches streams which both
are part of the program and match the additional_stream_specifier.

#stream_id or i:stream_id
Match the stream by stream id (e.g. PID in MPEG-TS container).

m:key[:value]
Matches streams with the metadata tag key having the specified value.
If value is not given, matches streams that contain the given tag with
any value. The colon character ':' in key or value needs to be back-
slash-escaped.

disp:dispositions[:additional_stream_specifier]
Matches streams with the given disposition(s). dispositions is a list
of one or more dispositions (as printed by the -dispositions option)
joined with '+'.

u Matches streams with usable configuration, the codec must be defined
and the essential information such as video dimension or audio sample
rate must be present.

Note that in ffmpeg, matching by metadata will only work properly for
input files.

Generic options
These options are shared amongst the ff* tools.

-L, -license
Show license.

-h, -?, -help, --help [arg]
Show help. An optional parameter may be specified to print help about a
specific item. If no argument is specified, only basic (non advanced)
tool options are shown.

Possible values of arg are:

longPrint advanced tool options in addition to the basic tool options.

fullPrint complete list of options, including shared and private op-
tions for encoders, decoders, demuxers, muxers, filters, etc.

decoder=decoder_name
Print detailed information about the decoder named decoder_name.
Use the -decoders option to get a list of all decoders.

encoder=encoder_name
Print detailed information about the encoder named encoder_name.
Use the -encoders option to get a list of all encoders.

demuxer=demuxer_name
Print detailed information about the demuxer named demuxer_name.
Use the -formats option to get a list of all demuxers and muxers.

muxer=muxer_name
Print detailed information about the muxer named muxer_name. Use
the -formats option to get a list of all muxers and demuxers.

filter=filter_name
Print detailed information about the filter named filter_name. Use
the -filters option to get a list of all filters.

bsf=bitstream_filter_name
Print detailed information about the bitstream filter named bit-
stream_filter_name. Use the -bsfs option to get a list of all bit-
stream filters.

protocol=protocol_name
Print detailed information about the protocol named protocol_name.
Use the -protocols option to get a list of all protocols.

-version
Show version.

-buildconf
Show the build configuration, one option per line.

-formats
Show available formats (including devices).

-demuxers
Show available demuxers.

-muxers
Show available muxers.

-devices
Show available devices.

-codecs
Show all codecs known to libavcodec.

Note that the term 'codec' is used throughout this documentation as a
shortcut for what is more correctly called a media bitstream format.

-decoders
Show available decoders.

-encoders
Show all available encoders.

-bsfs
Show available bitstream filters.

-protocols
Show available protocols.

-filters
Show available libavfilter filters.

-pix_fmts
Show available pixel formats.

-sample_fmts
Show available sample formats.

-layouts
Show channel names and standard channel layouts.

-dispositions
Show stream dispositions.

-colors
Show recognized color names.

-sources device[,opt1=val1[,opt2=val2]...]
Show autodetected sources of the input device. Some devices may pro-
vide system-dependent source names that cannot be autodetected. The
returned list cannot be assumed to be always complete.

ffmpeg -sources pulse,server=192.168.0.4

-sinks device[,opt1=val1[,opt2=val2]...]
Show autodetected sinks of the output device. Some devices may provide
system-dependent sink names that cannot be autodetected. The returned
list cannot be assumed to be always complete.

ffmpeg -sinks pulse,server=192.168.0.4

-loglevel [flags+]loglevel | -v [flags+]loglevel
Set logging level and flags used by the library.

The optional flags prefix can consist of the following values:

repeat
Indicates that repeated log output should not be compressed to the
first line and the "Last message repeated n times" line will be
omitted.

level
Indicates that log output should add a "[level]" prefix to each
message line. This can be used as an alternative to log coloring,
e.g. when dumping the log to file.

timeIndicates that log lines should be prefixed with time information.

datetime
Indicates that log lines should be prefixed with date and time in-
formation.

Flags can also be used alone by adding a '+'/'-' prefix to set/reset a
single flag without affecting other flags or changing loglevel. When
setting both flags and loglevel, a '+' separator is expected between
the last flags value and before loglevel.

loglevel is a string or a number containing one of the following val-
ues:

quiet, -8
Show nothing at all; be silent.

panic, 0
Only show fatal errors which could lead the process to crash, such
as an assertion failure. This is not currently used for anything.

fatal, 8
Only show fatal errors. These are errors after which the process
absolutely cannot continue.

error, 16
Show all errors, including ones which can be recovered from.

warning, 24
Show all warnings and errors. Any message related to possibly in-
correct or unexpected events will be shown.

info, 32
Show informative messages during processing. This is in addition to
warnings and errors. This is the default value.

verbose, 40
Same as "info", except more verbose.

debug, 48
Show everything, including debugging information.

trace, 56

For example to enable repeated log output, add the "level" prefix, and
set loglevel to "verbose":

ffmpeg -loglevel repeat+level+verbose -i input output

Another example that enables repeated log output without affecting cur-
rent state of "level" prefix flag or loglevel:

ffmpeg [...] -loglevel +repeat

By default the program logs to stderr. If coloring is supported by the
terminal, colors are used to mark errors and warnings. Log coloring can
be disabled setting the environment variable AV_LOG_FORCE_NOCOLOR, or
can be forced setting the environment variable AV_LOG_FORCE_COLOR.

-report
Dump full command line and log output to a file named "program-YYYYM-
MDD-HHMMSS.log" in the current directory. This file can be useful for
bug reports. It also implies "-loglevel debug".

Setting the environment variable FFREPORT to any value has the same ef-
fect. If the value is a ':'-separated key=value sequence, these options
will affect the report; option values must be escaped if they contain
special characters or the options delimiter ':' (see the ``Quoting and
escaping'' section in the ffmpeg-utils manual).

The following options are recognized:

fileset the file name to use for the report; %p is expanded to the name
of the program, %t is expanded to a timestamp, "%%" is expanded to
a plain "%"

level
set the log verbosity level using a numerical value (see
"-loglevel").

For example, to output a report to a file named ffreport.log using a
log level of 32 (alias for log level "info"):

FFREPORT=file=ffreport.log:level=32 ffmpeg -i input output

Errors in parsing the environment variable are not fatal, and will not
appear in the report.

-hide_banner
Suppress printing banner.

All FFmpeg tools will normally show a copyright notice, build options
and library versions. This option can be used to suppress printing this
information.

-cpuflags flags (global)
Allows setting and clearing cpu flags. This option is intended for
testing. Do not use it unless you know what you're doing.

ffmpeg -cpuflags -sse+mmx ...
ffmpeg -cpuflags mmx ...
ffmpeg -cpuflags 0 ...

Possible flags for this option are:

x86
mmx
mmxext
sse
sse2
sse2slow
sse3
sse3slow
ssse3
atom
sse4.1
sse4.2
avx
avx2
xop
fma3
fma4
3dnow
3dnowext
bmi1
bmi2
cmov

ARM
armv5te
armv6
armv6t2
vfp
vfpv3
neon
setend

AArch64
armv8
vfp
neon

PowerPC
altivec

Specific Processors
pentium2
pentium3
pentium4
k6
k62
athlon
athlonxp
k8

-cpucount count (global)
Override detection of CPU count. This option is intended for testing.
Do not use it unless you know what you're doing.

ffmpeg -cpucount 2

-max_alloc bytes
Set the maximum size limit for allocating a block on the heap by ffm-
peg's family of malloc functions. Exercise extreme caution when using
this option. Don't use if you do not understand the full consequence of
doing so. Default is INT_MAX.

AVOptions
These options are provided directly by the libavformat, libavdevice and
libavcodec libraries. To see the list of available AVOptions, use the -help
option. They are separated into two categories:

generic
These options can be set for any container, codec or device. Generic
options are listed under AVFormatContext options for containers/devices
and under AVCodecContext options for codecs.

private
These options are specific to the given container, device or codec.
Private options are listed under their corresponding containers/de-
vices/codecs.

For example to write an ID3v2.3 header instead of a default ID3v2.4 to an
MP3 file, use the id3v2_version private option of the MP3 muxer:

ffmpeg -i input.flac -id3v2_version 3 out.mp3

All codec AVOptions are per-stream, and thus a stream specifier should be
attached to them:

ffmpeg -i multichannel.mxf -map 0:v:0 -map 0:a:0 -map 0:a:0 -c:a:0 ac3 -b:a:0 640k -ac:a:1 2 -c:a:1 aac -b:2 128k out.mp4

In the above example, a multichannel audio stream is mapped twice for out-
put. The first instance is encoded with codec ac3 and bitrate 640k. The
second instance is downmixed to 2 channels and encoded with codec aac. A
bitrate of 128k is specified for it using absolute index of the output
stream.

Note: the -nooption syntax cannot be used for boolean AVOptions, use -op-
tion 0/-option 1.

Note: the old undocumented way of specifying per-stream AVOptions by
prepending v/a/s to the options name is now obsolete and will be removed
soon.

Main options
-f fmt (input/output)
Force input or output file format. The format is normally auto detected
for input files and guessed from the file extension for output files,
so this option is not needed in most cases.

-i url (input)
input file url

-y (global)
Overwrite output files without asking.

-n (global)
Do not overwrite output files, and exit immediately if a specified out-
put file already exists.

-stream_loop number (input)
Set number of times input stream shall be looped. Loop 0 means no loop,
loop -1 means infinite loop.

-recast_media (global)
Allow forcing a decoder of a different media type than the one detected
or designated by the demuxer. Useful for decoding media data muxed as
data streams.

-c[:stream_specifier] codec (input/output,per-stream)
-codec[:stream_specifier] codec (input/output,per-stream)
Select an encoder (when used before an output file) or a decoder (when
used before an input file) for one or more streams. codec is the name
of a decoder/encoder or a special value "copy" (output only) to indi-
cate that the stream is not to be re-encoded.

For example

ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT

encodes all video streams with libx264 and copies all audio streams.

For each stream, the last matching "c" option is applied, so

ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT

will copy all the streams except the second video, which will be en-
coded with libx264, and the 138th audio, which will be encoded with
libvorbis.

-t duration (input/output)
When used as an input option (before "-i"), limit the duration of data
read from the input file.

When used as an output option (before an output url), stop writing the
output after its duration reaches duration.

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

-to and -t are mutually exclusive and -t has priority.

-to position (input/output)
Stop writing the output or reading the input at position. position
must be a time duration specification, see the Time duration section in
the ffmpeg-utils(1) manual.

-to and -t are mutually exclusive and -t has priority.

-fs limit_size (output)
Set the file size limit, expressed in bytes. No further chunk of bytes
is written after the limit is exceeded. The size of the output file is
slightly more than the requested file size.

-ss position (input/output)
When used as an input option (before "-i"), seeks in this input file to
position. Note that in most formats it is not possible to seek exactly,
so ffmpeg will seek to the closest seek point before position. When
transcoding and -accurate_seek is enabled (the default), this extra
segment between the seek point and position will be decoded and dis-
carded. When doing stream copy or when -noaccurate_seek is used, it
will be preserved.

When used as an output option (before an output url), decodes but dis-
cards input until the timestamps reach position.

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

-sseof position (input)
Like the "-ss" option but relative to the "end of file". That is nega-
tive values are earlier in the file, 0 is at EOF.

-isync input_index (input)
Assign an input as a sync source.

This will take the difference between the start times of the target and
reference inputs and offset the timestamps of the target file by that
difference. The source timestamps of the two inputs should derive from
the same clock source for expected results. If "copyts" is set then
"start_at_zero" must also be set. If either of the inputs has no start-
ing timestamp then no sync adjustment is made.

Acceptable values are those that refer to a valid ffmpeg input index.
If the sync reference is the target index itself or -1, then no adjust-
ment is made to target timestamps. A sync reference may not itself be
synced to any other input.

Default value is -1.

-itsoffset offset (input)
Set the input time offset.

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

The offset is added to the timestamps of the input files. Specifying a
positive offset means that the corresponding streams are delayed by the
time duration specified in offset.

-itsscale scale (input,per-stream)
Rescale input timestamps. scale should be a floating point number.

-timestamp date (output)
Set the recording timestamp in the container.

date must be a date specification, see the Date section in the ffm-
peg-utils(1) manual.

-metadata[:metadata_specifier] key=value (output,per-metadata)
Set a metadata key/value pair.

An optional metadata_specifier may be given to set metadata on streams,
chapters or programs. See "-map_metadata" documentation for details.

This option overrides metadata set with "-map_metadata". It is also
possible to delete metadata by using an empty value.

For example, for setting the title in the output file:

ffmpeg -i in.avi -metadata title="my title" out.flv

To set the language of the first audio stream:

ffmpeg -i INPUT -metadata:s:a:0 language=eng OUTPUT

-disposition[:stream_specifier] value (output,per-stream)
Sets the disposition flags for a stream.

Default value: by default, all disposition flags are copied from the
input stream, unless the output stream this option applies to is fed by
a complex filtergraph - in that case no disposition flags are set by
default.

value is a sequence of disposition flags separated by '+' or '-'. A '+'
prefix adds the given disposition, '-' removes it. If the first flag is
also prefixed with '+' or '-', the resulting disposition is the default
value updated by value. If the first flag is not prefixed, the result-
ing disposition is value. It is also possible to clear the disposition
by setting it to 0.

If no "-disposition" options were specified for an output file, ffmpeg
will automatically set the 'default' disposition flag on the first
stream of each type, when there are multiple streams of this type in
the output file and no stream of that type is already marked as de-
fault.

The "-dispositions" option lists the known disposition flags.

For example, to make the second audio stream the default stream:

ffmpeg -i in.mkv -c copy -disposition:a:1 default out.mkv

To make the second subtitle stream the default stream and remove the
default disposition from the first subtitle stream:

ffmpeg -i in.mkv -c copy -disposition:s:0 0 -disposition:s:1 default out.mkv

To add an embedded cover/thumbnail:

ffmpeg -i in.mp4 -i IMAGE -map 0 -map 1 -c copy -c:v:1 png -disposition:v:1 attached_pic out.mp4

To add the 'original' and remove the 'comment' disposition flag from
the first audio stream without removing its other disposition flags:

ffmpeg -i in.mkv -c copy -disposition:a:0 +original-comment out.mkv

To remove the 'original' and add the 'comment' disposition flag to the
first audio stream without removing its other disposition flags:

ffmpeg -i in.mkv -c copy -disposition:a:0 -original+comment out.mkv

To set only the 'original' and 'comment' disposition flags on the first
audio stream (and remove its other disposition flags):

ffmpeg -i in.mkv -c copy -disposition:a:0 original+comment out.mkv

To remove all disposition flags from the first audio stream:

ffmpeg -i in.mkv -c copy -disposition:a:0 0 out.mkv

Not all muxers support embedded thumbnails, and those who do, only sup-
port a few formats, like JPEG or PNG.

-program [title=title:][program_num=program_num:]st=stream[:st=stream...]
(output)
Creates a program with the specified title, program_num and adds the
specified stream(s) to it.

-stream_group [map=in-
put_file_id=stream_group][type=type:]st=stream[:st=stream][:stg=stream_group][:id=stream_group_id...]
(output)
Creates a stream group of the specified type and stream_group_id, or by
mapping an input group, adding the specified stream(s) and/or previ-
ously defined stream_group(s) to it.

type can be one of the following:

iamf_audio_element
Groups streams that belong to the same IAMF Audio Element

For this group type, the following options are available

audio_element_type
The Audio Element type. The following values are supported:

channel
Scalable channel audio representation

scene
Ambisonics representation

demixing
Demixing information used to reconstruct a scalable channel au-
dio representation. This option must be separated from the
rest with a ',', and takes the following key=value options

parameter_id
An identifier parameters blocks in frames may refer to

dmixp_mode
A pre-defined combination of demixing parameters

recon_gain
Recon gain information used to reconstruct a scalable channel
audio representation. This option must be separated from the
rest with a ',', and takes the following key=value options

parameter_id
An identifier parameters blocks in frames may refer to

layer
A layer defining a Channel Layout in the Audio Element. This
option must be separated from the rest with a ','. Several ','
separated entries can be defined, and at least one must be set.

It takes the following ":"-separated key=value options

ch_layout
The layer's channel layout

flags
The following flags are available:

recon_gain
Whether to signal if recon_gain is present as metadata
in parameter blocks within frames

output_gain
output_gain_flags
Which channels output_gain applies to. The following flags
are available:

FL
FR
BL
BR
TFL
TFR

ambisonics_mode
The ambisonics mode. This has no effect if audio_ele-
ment_type is set to channel.

The following values are supported:

monoEach ambisonics channel is coded as an individual mono
stream in the group

default_w
Default weight value

iamf_mix_presentation
Groups streams that belong to all IAMF Audio Element the same IAMF
Mix Presentation references

For this group type, the following options are available

submix
A sub-mix within the Mix Presentation. This option must be
separated from the rest with a ','. Several ',' separated en-
tries can be defined, and at least one must be set.

It takes the following ":"-separated key=value options

parameter_id
An identifier parameters blocks in frames may refer to, for
post-processing the mixed audio signal to generate the au-
dio signal for playback

parameter_rate
The sample rate duration fields in parameters blocks in
frames that refer to this parameter_id are expressed as

default_mix_gain
Default mix gain value to apply when there are no parameter
blocks sharing the same parameter_id for a given frame

element
References an Audio Element used in this Mix Presentation
to generate the final output audio signal for playback.
This option must be separated from the rest with a '|'.
Several '|' separated entries can be defined, and at least
one must be set.

It takes the following ":"-separated key=value options:

stg The stream_group_id for an Audio Element which this
sub-mix refers to

parameter_id
An identifier parameters blocks in frames may refer to,
for applying any processing to the referenced and ren-
dered Audio Element before being summed with other
processed Audio Elements

parameter_rate
The sample rate duration fields in parameters blocks in
frames that refer to this parameter_id are expressed as

default_mix_gain
Default mix gain value to apply when there are no para-
meter blocks sharing the same parameter_id for a given
frame

annotations
A key=value string describing the sub-mix element where
"key" is a string conforming to BCP-47 that specifies
the language for the "value" string. "key" must be the
same as the one in the mix's annotations

headphones_rendering_mode
Indicates whether the input channel-based Audio Element
is rendered to stereo loudspeakers or spatialized with
a binaural renderer when played back on headphones.
This has no effect if the referenced Audio Element's
audio_element_type is set to channel.

The following values are supported:

stereo
binaural

layout
Specifies the layouts for this sub-mix on which the loud-
ness information was measured. This option must be sepa-
rated from the rest with a '|'. Several '|' separated en-
tries can be defined, and at least one must be set.

It takes the following ":"-separated key=value options:

layout_type
loudspeakers
The layout follows the loudspeaker sound system
convention of ITU-2051-3.

binaural
The layout is binaural.

sound_system
Channel layout matching one of Sound Systems A to J of
ITU-2051-3, plus 7.1.2 and 3.1.2 This has no effect if
layout_type is set to binaural.

integrated_loudness
The program integrated loudness information, as defined
in ITU-1770-4.

digital_peak
The digital (sampled) peak value of the audio signal,
as defined in ITU-1770-4.

true_peak
The true peak of the audio signal, as defined in
ITU-1770-4.

dialog_anchored_loudness
The Dialogue loudness information, as defined in
ITU-1770-4.

album_anchored_loudness
The Album loudness information, as defined in
ITU-1770-4.

annotations
A key=value string string describing the mix where "key" is a
string conforming to BCP-47 that specifies the language for the
"value" string. "key" must be the same as the ones in all
sub-mix element's annotationss

E.g. to create an scalable 5.1 IAMF file from several WAV input files

ffmpeg -i front.wav -i back.wav -i center.wav -i lfe.wav
-map 0:0 -map 1:0 -map 2:0 -map 3:0 -c:a opus
-stream_group type=iamf_audio_element:id=1:st=0:st=1:st=2:st=3,
demixing=parameter_id=998,
recon_gain=parameter_id=101,
layer=ch_layout=stereo,
layer=ch_layout=5.1(side),
-stream_group type=iamf_mix_presentation:id=2:stg=0:annotations=en-us=Mix_Presentation,
submix=parameter_id=100:parameter_rate=48000|element=stg=0:parameter_id=100:annotations=en-us=Scalable_Submix|layout=sound_system=stereo|layout=sound_system=5.1(side)
-streamid 0:0 -streamid 1:1 -streamid 2:2 -streamid 3:3 output.iamf

To copy the two stream groups (Audio Element and Mix Presentation) from
an input IAMF file with four streams into an mp4 output

ffmpeg -i input.iamf -c:a copy -stream_group map=0=0:st=0:st=1:st=2:st=3 -stream_group map=0=1:stg=0
-streamid 0:0 -streamid 1:1 -streamid 2:2 -streamid 3:3 output.mp4

-target type (output)
Specify target file type ("vcd", "svcd", "dvd", "dv", "dv50"). type may
be prefixed with "pal-", "ntsc-" or "film-" to use the corresponding
standard. All the format options (bitrate, codecs, buffer sizes) are
then set automatically. You can just type:

ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg

Nevertheless you can specify additional options as long as you know
they do not conflict with the standard, as in:

ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg

The parameters set for each target are as follows.

VCD

<pal>:
-f vcd -muxrate 1411200 -muxpreload 0.44 -packetsize 2324
-s 352x288 -r 25
-codec:v mpeg1video -g 15 -b:v 1150k -maxrate:v 1150k -minrate:v 1150k -bufsize:v 327680
-ar 44100 -ac 2
-codec:a mp2 -b:a 224k

<ntsc>:
-f vcd -muxrate 1411200 -muxpreload 0.44 -packetsize 2324
-s 352x240 -r 30000/1001
-codec:v mpeg1video -g 18 -b:v 1150k -maxrate:v 1150k -minrate:v 1150k -bufsize:v 327680
-ar 44100 -ac 2
-codec:a mp2 -b:a 224k

<film>:
-f vcd -muxrate 1411200 -muxpreload 0.44 -packetsize 2324
-s 352x240 -r 24000/1001
-codec:v mpeg1video -g 18 -b:v 1150k -maxrate:v 1150k -minrate:v 1150k -bufsize:v 327680
-ar 44100 -ac 2
-codec:a mp2 -b:a 224k

SVCD

<pal>:
-f svcd -packetsize 2324
-s 480x576 -pix_fmt yuv420p -r 25
-codec:v mpeg2video -g 15 -b:v 2040k -maxrate:v 2516k -minrate:v 0 -bufsize:v 1835008 -scan_offset 1
-ar 44100
-codec:a mp2 -b:a 224k

<ntsc>:
-f svcd -packetsize 2324
-s 480x480 -pix_fmt yuv420p -r 30000/1001
-codec:v mpeg2video -g 18 -b:v 2040k -maxrate:v 2516k -minrate:v 0 -bufsize:v 1835008 -scan_offset 1
-ar 44100
-codec:a mp2 -b:a 224k

<film>:
-f svcd -packetsize 2324
-s 480x480 -pix_fmt yuv420p -r 24000/1001
-codec:v mpeg2video -g 18 -b:v 2040k -maxrate:v 2516k -minrate:v 0 -bufsize:v 1835008 -scan_offset 1
-ar 44100
-codec:a mp2 -b:a 224k

DVD

<pal>:
-f dvd -muxrate 10080k -packetsize 2048
-s 720x576 -pix_fmt yuv420p -r 25
-codec:v mpeg2video -g 15 -b:v 6000k -maxrate:v 9000k -minrate:v 0 -bufsize:v 1835008
-ar 48000
-codec:a ac3 -b:a 448k

<ntsc>:
-f dvd -muxrate 10080k -packetsize 2048
-s 720x480 -pix_fmt yuv420p -r 30000/1001
-codec:v mpeg2video -g 18 -b:v 6000k -maxrate:v 9000k -minrate:v 0 -bufsize:v 1835008
-ar 48000
-codec:a ac3 -b:a 448k

<film>:
-f dvd -muxrate 10080k -packetsize 2048
-s 720x480 -pix_fmt yuv420p -r 24000/1001
-codec:v mpeg2video -g 18 -b:v 6000k -maxrate:v 9000k -minrate:v 0 -bufsize:v 1835008
-ar 48000
-codec:a ac3 -b:a 448k

<pal>:
-f dv
-s 720x576 -pix_fmt yuv420p -r 25
-ar 48000 -ac 2

<ntsc>:
-f dv
-s 720x480 -pix_fmt yuv411p -r 30000/1001
-ar 48000 -ac 2

<film>:
-f dv
-s 720x480 -pix_fmt yuv411p -r 24000/1001
-ar 48000 -ac 2

The "dv50" target is identical to the "dv" target except that the pixel
format set is "yuv422p" for all three standards.

Any user-set value for a parameter above will override the target pre-
set value. In that case, the output may not comply with the target
standard.

-dn (input/output)
As an input option, blocks all data streams of a file from being fil-
tered or being automatically selected or mapped for any output. See
"-discard" option to disable streams individually.

As an output option, disables data recording i.e. automatic selection
or mapping of any data stream. For full manual control see the "-map"
option.

-dframes number (output)
Set the number of data frames to output. This is an obsolete alias for
"-frames:d", which you should use instead.

-frames[:stream_specifier] framecount (output,per-stream)
Stop writing to the stream after framecount frames.

-q[:stream_specifier] q (output,per-stream)
-qscale[:stream_specifier] q (output,per-stream)
Use fixed quality scale (VBR). The meaning of q/qscale is codec-depen-
dent. If qscale is used without a stream_specifier then it applies
only to the video stream, this is to maintain compatibility with previ-
ous behavior and as specifying the same codec specific value to 2 dif-
ferent codecs that is audio and video generally is not what is intended
when no stream_specifier is used.

-filter[:stream_specifier] filtergraph (output,per-stream)
Create the filtergraph specified by filtergraph and use it to filter
the stream.

filtergraph is a description of the filtergraph to apply to the stream,
and must have a single input and a single output of the same type of
the stream. In the filtergraph, the input is associated to the label
"in", and the output to the label "out". See the ffmpeg-filters manual
for more information about the filtergraph syntax.

See the -filter_complex option if you want to create filtergraphs with
multiple inputs and/or outputs.

-reinit_filter[:stream_specifier] integer (input,per-stream)
This boolean option determines if the filtergraph(s) to which this
stream is fed gets reinitialized when input frame parameters change
mid-stream. This option is enabled by default as most video and all au-
dio filters cannot handle deviation in input frame properties. Upon
reinitialization, existing filter state is lost, like e.g. the frame
count "n" reference available in some filters. Any frames buffered at
time of reinitialization are lost. The properties where a change trig-
gers reinitialization are, for video, frame resolution or pixel format;
for audio, sample format, sample rate, channel count or channel layout.

-drop_changed[:stream_specifier] integer (input,per-stream)
This boolean option determines whether a frame with differing frame pa-
rameters mid-stream gets dropped instead of leading to filtergraph
reinitialization, as that would lead to loss of filter state. Generally
useful to avoid corrupted yet decodable packets in live streaming in-
puts. Default is false.

-filter_threads nb_threads (global)
Defines how many threads are used to process a filter pipeline. Each
pipeline will produce a thread pool with this many threads available
for parallel processing. The default is the number of available CPUs.

-filter_buffered_frames nb_frames (global)
Defines the maximum number of buffered frames allowed in a filtergraph.
Under normal circumstances, a filtergraph should not buffer more than a
few frames, especially if frames are being fed to it and read from it
in a balanced way (which is the intended behavior in ffmpeg). That
said, this option allows you to limit the total number of frames
buffered across all links in a filtergraph. If more frames are gener-
ated, filtering is aborted and an error is returned. The default value
is 0, which means no limit.

-pre[:stream_specifier] preset_name (output,per-stream)
Specify the preset for matching stream(s).

-stats (global)
Log encoding progress/statistics as "info"-level log (see "-loglevel").
It is on by default, to explicitly disable it you need to specify
"-nostats".

-stats_period time (global)
Set period at which encoding progress/statistics are updated. Default
is 0.5 seconds.

-print_graphs (global)
Prints execution graph details to stderr in the format set via
-print_graphs_format.

-print_graphs_file filename (global)
Writes execution graph details to the specified file in the format set
via -print_graphs_format.

-print_graphs_format format (global)
Sets the output format (available formats are: default, compact, csv,
flat, ini, json, xml, mermaid, mermaidhtml) The default format is json.

-progress url (global)
Send program-friendly progress information to url.

Progress information is written periodically and at the end of the en-
coding process. It is made of "key=value" lines. key consists of only
alphanumeric characters. The last key of a sequence of progress infor-
mation is always "progress" with the value "continue" or "end".

The update period is set using "-stats_period".

For example, log progress information to stdout:

ffmpeg -progress pipe:1 -i in.mkv out.mkv

-stdin
Enable interaction on standard input. On by default unless standard in-
put is used as an input. To explicitly disable interaction you need to
specify "-nostdin".

Disabling interaction on standard input is useful, for example, if ffm-
peg is in the background process group. Roughly the same result can be
achieved with "ffmpeg ... < /dev/null" but it requires a shell.

-debug_ts (global)
Print timestamp/latency information. It is off by default. This option
is mostly useful for testing and debugging purposes, and the output
format may change from one version to another, so it should not be em-
ployed by portable scripts.

See also the option "-fdebug ts".

-attach filename (output)
Add an attachment to the output file. This is supported by a few for-
mats like Matroska for e.g. fonts used in rendering subtitles. Attach-
ments are implemented as a specific type of stream, so this option will
add a new stream to the file. It is then possible to use per-stream op-
tions on this stream in the usual way. Attachment streams created with
this option will be created after all the other streams (i.e. those
created with "-map" or automatic mappings).

Note that for Matroska you also have to set the mimetype metadata tag:

ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv

(assuming that the attachment stream will be third in the output file).

-dump_attachment[:stream_specifier] filename (input,per-stream)
Extract the matching attachment stream into a file named filename. If
filename is empty, then the value of the "filename" metadata tag will
be used.

E.g. to extract the first attachment to a file named 'out.ttf':

ffmpeg -dump_attachment:t:0 out.ttf -i INPUT

To extract all attachments to files determined by the "filename" tag:

ffmpeg -dump_attachment:t "" -i INPUT

Technical note -- attachments are implemented as codec extradata, so
this option can actually be used to extract extradata from any stream,
not just attachments.

Video Options
-vframes number (output)
Set the number of video frames to output. This is an obsolete alias for
"-frames:v", which you should use instead.

-r[:stream_specifier] fps (input/output,per-stream)
Set frame rate (Hz value, fraction or abbreviation).

As an input option, ignore any timestamps stored in the file and in-
stead generate timestamps assuming constant frame rate fps. This is
not the same as the -framerate option used for some input formats like
image2 or v4l2 (it used to be the same in older versions of FFmpeg).
If in doubt use -framerate instead of the input option -r.

As an output option:

video encoding
Duplicate or drop frames right before encoding them to achieve con-
stant output frame rate fps.

video streamcopy
Indicate to the muxer that fps is the stream frame rate. No data is
dropped or duplicated in this case. This may produce invalid files
if fps does not match the actual stream frame rate as determined by
packet timestamps. See also the "setts" bitstream filter.

-fpsmax[:stream_specifier] fps (output,per-stream)
Set maximum frame rate (Hz value, fraction or abbreviation).

Clamps output frame rate when output framerate is auto-set and is
higher than this value. Useful in batch processing or when input fram-
erate is wrongly detected as very high. It cannot be set together with
"-r". It is ignored during streamcopy.

-s[:stream_specifier] size (input/output,per-stream)
Set frame size.

As an input option, this is a shortcut for the video_size private op-
tion, recognized by some demuxers for which the frame size is either
not stored in the file or is configurable -- e.g. raw video or video
grabbers.

As an output option, this inserts the "scale" video filter to the end
of the corresponding filtergraph. Please use the "scale" filter di-
rectly to insert it at the beginning or some other place.

The format is wxh (default - same as source).

-aspect[:stream_specifier] aspect (output,per-stream)
Set the video display aspect ratio specified by aspect.

aspect can be a floating point number string, or a string of the form
num:den, where num and den are the numerator and denominator of the as-
pect ratio. For example "4:3", "16:9", "1.3333", and "1.7777" are valid
argument values.

If used together with -vcodec copy, it will affect the aspect ratio
stored at container level, but not the aspect ratio stored in encoded
frames, if it exists.

-display_rotation[:stream_specifier] rotation (input,per-stream)
Set video rotation metadata.

rotation is a decimal number specifying the amount in degree by which
the video should be rotated counter-clockwise before being displayed.

This option overrides the rotation/display transform metadata stored in
the file, if any. When the video is being transcoded (rather than
copied) and "-autorotate" is enabled, the video will be rotated at the
filtering stage. Otherwise, the metadata will be written into the out-
put file if the muxer supports it.

If the "-display_hflip" and/or "-display_vflip" options are given, they
are applied after the rotation specified by this option.

-display_hflip[:stream_specifier] (input,per-stream)
Set whether on display the image should be horizontally flipped.

See the "-display_rotation" option for more details.

-display_vflip[:stream_specifier] (input,per-stream)
Set whether on display the image should be vertically flipped.

See the "-display_rotation" option for more details.

-vn (input/output)
As an input option, blocks all video streams of a file from being fil-
tered or being automatically selected or mapped for any output. See
"-discard" option to disable streams individually.

As an output option, disables video recording i.e. automatic selection
or mapping of any video stream. For full manual control see the "-map"
option.

-vcodec codec (output)
Set the video codec. This is an alias for "-codec:v".

-pass[:stream_specifier] n (output,per-stream)
Select the pass number (1 or 2). It is used to do two-pass video encod-
ing. The statistics of the video are recorded in the first pass into a
log file (see also the option -passlogfile), and in the second pass
that log file is used to generate the video at the exact requested bi-
trate. On pass 1, you may just deactivate audio and set output to
null, examples for Windows and Unix:

ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL
ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null

-passlogfile[:stream_specifier] prefix (output,per-stream)
Set two-pass log file name prefix to prefix, the default file name pre-
fix is ``ffmpeg2pass''. The complete file name will be PREFIX-N.log,
where N is a number specific to the output stream

-vf filtergraph (output)
Create the filtergraph specified by filtergraph and use it to filter
the stream.

This is an alias for "-filter:v", see the -filter option.

-autorotate
Automatically rotate the video according to file metadata. Enabled by
default, use -noautorotate to disable it.

-autoscale
Automatically scale the video according to the resolution of first
frame. Enabled by default, use -noautoscale to disable it. When au-
toscale is disabled, all output frames of filter graph might not be in
the same resolution and may be inadequate for some encoder/muxer.
Therefore, it is not recommended to disable it unless you really know
what you are doing. Disable autoscale at your own risk.

Advanced Video options
-pix_fmt[:stream_specifier] format (input/output,per-stream)
Set pixel format. Use "-pix_fmts" to show all the supported pixel for-
mats. If the selected pixel format can not be selected, ffmpeg will
print a warning and select the best pixel format supported by the en-
coder. If pix_fmt is prefixed by a "+", ffmpeg will exit with an error
if the requested pixel format can not be selected, and automatic con-
versions inside filtergraphs are disabled. If pix_fmt is a single "+",
ffmpeg selects the same pixel format as the input (or graph output) and
automatic conversions are disabled.

-sws_flags flags (input/output)
Set default flags for the libswscale library. These flags are used by
automatically inserted "scale" filters and those within simple filter-
graphs, if not overridden within the filtergraph definition.

See the ffmpeg-scaler manual for a list of scaler options.

-rc_override[:stream_specifier] override (output,per-stream)
Rate control override for specific intervals, formatted as
"int,int,int" list separated with slashes. Two first values are the be-
ginning and end frame numbers, last one is quantizer to use if posi-
tive, or quality factor if negative.

-vstats
Dump video coding statistics to vstats_HHMMSS.log. See the vstats file
format section for the format description.

-vstats_file file
Dump video coding statistics to file. See the vstats file format sec-
tion for the format description.

-vstats_version file
Specify which version of the vstats format to use. Default is 2. See
the vstats file format section for the format description.

-vtag fourcc/tag (output)
Force video tag/fourcc. This is an alias for "-tag:v".

-force_key_frames[:stream_specifier] time[,time...] (output,per-stream)
-force_key_frames[:stream_specifier] expr:expr (output,per-stream)
-force_key_frames[:stream_specifier] source (output,per-stream)
-force_key_frames[:stream_specifier] scd_metadata (output,per-stream)
force_key_frames can take arguments of the following form:

time[,time...]
If the argument consists of timestamps, ffmpeg will round the spec-
ified times to the nearest output timestamp as per the encoder time
base and force a keyframe at the first frame having timestamp equal
or greater than the computed timestamp. Note that if the encoder
time base is too coarse, then the keyframes may be forced on frames
with timestamps lower than the specified time. The default encoder
time base is the inverse of the output framerate but may be set
otherwise via "-enc_time_base".

If one of the times is ""chapters"[delta]", it is expanded into the
time of the beginning of all chapters in the file, shifted by
delta, expressed as a time in seconds. This option can be useful
to ensure that a seek point is present at a chapter mark or any
other designated place in the output file.

For example, to insert a key frame at 5 minutes, plus key frames
0.1 second before the beginning of every chapter:

-force_key_frames 0:05:00,chapters-0.1

expr:expr
If the argument is prefixed with "expr:", the string expr is inter-
preted like an expression and is evaluated for each frame. A key
frame is forced in case the evaluation is non-zero.

The expression in expr can contain the following constants:

n the number of current processed frame, starting from 0

n_forced
the number of forced frames

prev_forced_n
the number of the previous forced frame, it is "NAN" when no
keyframe was forced yet

prev_forced_t
the time of the previous forced frame, it is "NAN" when no
keyframe was forced yet

t the time of the current processed frame

For example to force a key frame every 5 seconds, you can specify:

-force_key_frames expr:gte(t,n_forced*5)

To force a key frame 5 seconds after the time of the last forced
one, starting from second 13:

-force_key_frames expr:if(isnan(prev_forced_t),gte(t,13),gte(t,prev_forced_t+5))

source
If the argument is "source", ffmpeg will force a key frame if the
current frame being encoded is marked as a key frame in its source.
In cases where this particular source frame has to be dropped, en-
force the next available frame to become a key frame instead.

scd_metadata
If the argument is "scd_metadata", ffmpeg will force a key frame if
the current frame contains a metadata entry with the key
"lavfi.scd.time". The metadata can be added by filters like
"scdet" and "scdet_vulkan". Avoid inserting filters that duplicate
frames after "scdet", as this can cause duplicate metadata for mul-
tiple frames and repeated insertion of key frames.

Note that forcing too many keyframes is very harmful for the lookahead
algorithms of certain encoders: using fixed-GOP options or similar
would be more efficient.

-apply_cropping[:stream_specifier] source (input,per-stream)
Automatically crop the video after decoding according to file metadata.
Default is all.

none (0)
Don't apply any cropping metadata.

all (1)
Apply both codec and container level croppping. This is the default
mode.

codec (2)
Apply codec level croppping.

container (3)
Apply container level croppping.

-copyinkf[:stream_specifier] (output,per-stream)
When doing stream copy, copy also non-key frames found at the begin-
ning.

-init_hw_device type[=name][:device[,key=value...]]
Initialise a new hardware device of type type called name, using the
given device parameters. If no name is specified it will receive a de-
fault name of the form "type%d".

The meaning of device and the following arguments depends on the device
type:

cudadevice is the number of the CUDA device.

The following options are recognized:

primary_ctx
If set to 1, uses the primary device context instead of creat-
ing a new one.

Examples:

-init_hw_device cuda:1
Choose the second device on the system.

-init_hw_device cuda:0,primary_ctx=1
Choose the first device and use the primary device context.

dxva2
device is the number of the Direct3D 9 display adapter.

d3d11va
device is the number of the Direct3D 11 display adapter. If not
specified, it will attempt to use the default Direct3D 11 display
adapter or the first Direct3D 11 display adapter whose hardware
VendorId is specified by vendor_id.

Examples:

-init_hw_device d3d11va
Create a d3d11va device on the default Direct3D 11 display
adapter.

-init_hw_device d3d11va:1
Create a d3d11va device on the Direct3D 11 display adapter
specified by index 1.

-init_hw_device d3d11va:,vendor_id=0x8086
Create a d3d11va device on the first Direct3D 11 display
adapter whose hardware VendorId is 0x8086.

vaapi
device is either an X11 display name, a DRM render node or a Di-
rectX adapter index. If not specified, it will attempt to open the
default X11 display ($DISPLAY) and then the first DRM render node
(/dev/dri/renderD128), or the default DirectX adapter on Windows.

The following options are recognized:

kernel_driver
When device is not specified, use this option to specify the
name of the kernel driver associated with the desired device.
This option is available only when the hardware acceleration
method drm and vaapi are enabled.

vendor_id
When device and kernel_driver are not specified, use this op-
tion to specify the vendor id associated with the desired de-
vice. This option is available only when the hardware accelera-
tion method drm and vaapi are enabled and kernel_driver is not
specified.

Examples:

-init_hw_device vaapi
Create a vaapi device on the default device.

-init_hw_device vaapi:/dev/dri/renderD129
Create a vaapi device on DRM render node /dev/dri/renderD129.

-init_hw_device vaapi:1
Create a vaapi device on DirectX adapter 1.

-init_hw_device vaapi:,kernel_driver=i915
Create a vaapi device on a device associated with kernel driver
i915.

-init_hw_device vaapi:,vendor_id=0x8086
Create a vaapi device on a device associated with vendor id
0x8086.

vdpau
device is an X11 display name. If not specified, it will attempt
to open the default X11 display ($DISPLAY).

qsv device selects a value in MFX_IMPL_*. Allowed values are:

auto
sw
hw
auto_any
hw_any
hw2
hw3
hw4

If not specified, auto_any is used. (Note that it may be easier to
achieve the desired result for QSV by creating the platform-appro-
priate subdevice (dxva2 or d3d11va or vaapi) and then deriving a
QSV device from that.)

The following options are recognized:

child_device
Specify a DRM render node on Linux or DirectX adapter on Win-
dows.

child_device_type
Choose platform-appropriate subdevice type. On Windows d3d11va
is used as default subdevice type when "--enable-libvpl" is
specified at configuration time, dxva2 is used as default sub-
device type when "--enable-libmfx" is specified at configura-
tion time. On Linux user can use vaapi only as subdevice type.

Examples:

-init_hw_device qsv:hw,child_device=/dev/dri/renderD129
Create a QSV device with MFX_IMPL_HARDWARE on DRM render node
/dev/dri/renderD129.

-init_hw_device qsv:hw,child_device=1
Create a QSV device with MFX_IMPL_HARDWARE on DirectX adapter
1.

-init_hw_device qsv:hw,child_device_type=d3d11va
Choose the GPU subdevice with type d3d11va and create QSV de-
vice with MFX_IMPL_HARDWARE.

-init_hw_device qsv:hw,child_device_type=dxva2
Choose the GPU subdevice with type dxva2 and create QSV device
with MFX_IMPL_HARDWARE.

-init_hw_device qsv:hw,child_device=1,child_device_type=d3d11va
Create a QSV device with MFX_IMPL_HARDWARE on DirectX adapter 1
with subdevice type d3d11va.

-init_hw_device vaapi=va:/dev/dri/renderD129 -init_hw_device
qsv=hw1@va
Create a VAAPI device called va on /dev/dri/renderD129, then
derive a QSV device called hw1 from device va.

opencl
device selects the platform and device as platform_index.device_in-
dex.

The set of devices can also be filtered using the key-value pairs
to find only devices matching particular platform or device
strings.

The strings usable as filters are:

platform_profile
platform_version
platform_name
platform_vendor
platform_extensions
device_name
device_vendor
driver_version
device_version
device_profile
device_extensions
device_type

The indices and filters must together uniquely select a device.

Examples:

-init_hw_device opencl:0.1
Choose the second device on the first platform.

-init_hw_device opencl:,device_name=Foo9000
Choose the device with a name containing the string Foo9000.

-init_hw_device opencl:1,device_type=gpu,device_exten-
sions=cl_khr_fp16
Choose the GPU device on the second platform supporting the
cl_khr_fp16 extension.

vulkan
If device is an integer, it selects the device by its index in a
system-dependent list of devices. If device is any other string,
it selects the first device with a name containing that string as a
substring.

The following options are recognized:

debug
If set to 1, enables the validation layer, if installed.

linear_images
If set to 1, images allocated by the hwcontext will be linear
and locally mappable.

instance_extensions
A plus separated list of additional instance extensions to en-
able.

device_extensions
A plus separated list of additional device extensions to en-
able.

Examples:

-init_hw_device vulkan:1
Choose the second device on the system.

-init_hw_device vulkan:RADV
Choose the first device with a name containing the string RADV.

-init_hw_device vulkan:0,instance_extensions=VK_KHR_wayland_sur-
face+VK_KHR_xcb_surface
Choose the first device and enable the Wayland and XCB instance
extensions.

-init_hw_device type[=name]@source
Initialise a new hardware device of type type called name, deriving it
from the existing device with the name source.

-init_hw_device list
List all hardware device types supported in this build of ffmpeg.

-filter_hw_device name
Pass the hardware device called name to all filters in any filter
graph. This can be used to set the device to upload to with the "hwu-
pload" filter, or the device to map to with the "hwmap" filter. Other
filters may also make use of this parameter when they require a hard-
ware device. Note that this is typically only required when the input
is not already in hardware frames - when it is, filters will derive the
device they require from the context of the frames they receive as in-
put.

This is a global setting, so all filters will receive the same device.

-hwaccel[:stream_specifier] hwaccel (input,per-stream)
Use hardware acceleration to decode the matching stream(s). The allowed
values of hwaccel are:

noneDo not use any hardware acceleration (the default).

autoAutomatically select the hardware acceleration method.

vdpau
Use VDPAU (Video Decode and Presentation API for Unix) hardware ac-
celeration.

dxva2
Use DXVA2 (DirectX Video Acceleration) hardware acceleration.

d3d11va
Use D3D11VA (DirectX Video Acceleration) hardware acceleration.

vaapi
Use VAAPI (Video Acceleration API) hardware acceleration.

qsv Use the Intel QuickSync Video acceleration for video transcoding.

Unlike most other values, this option does not enable accelerated
decoding (that is used automatically whenever a qsv decoder is se-
lected), but accelerated transcoding, without copying the frames
into the system memory.

For it to work, both the decoder and the encoder must support QSV
acceleration and no filters must be used.

videotoolbox
Use Video Toolbox hardware acceleration.

This option has no effect if the selected hwaccel is not available or
not supported by the chosen decoder.

Note that most acceleration methods are intended for playback and will
not be faster than software decoding on modern CPUs. Additionally, ffm-
peg will usually need to copy the decoded frames from the GPU memory
into the system memory, resulting in further performance loss. This op-
tion is thus mainly useful for testing.

-hwaccel_device[:stream_specifier] hwaccel_device (input,per-stream)
Select a device to use for hardware acceleration.

This option only makes sense when the -hwaccel option is also speci-
fied. It can either refer to an existing device created with
-init_hw_device by name, or it can create a new device as if
-init_hw_device type:hwaccel_device were called immediately before.

-hwaccels
List all hardware acceleration components enabled in this build of ffm-
peg. Actual runtime availability depends on the hardware and its suit-
able driver being installed.

-fix_sub_duration_heartbeat[:stream_specifier]
Set a specific output video stream as the heartbeat stream according to
which to split and push through currently in-progress subtitle upon re-
ceipt of a random access packet.

This lowers the latency of subtitles for which the end packet or the
following subtitle has not yet been received. As a drawback, this will
most likely lead to duplication of subtitle events in order to cover
the full duration, so when dealing with use cases where latency of when
the subtitle event is passed on to output is not relevant this option
should not be utilized.

Requires -fix_sub_duration to be set for the relevant input subtitle
stream for this to have any effect, as well as for the input subtitle
stream having to be directly mapped to the same output in which the
heartbeat stream resides.

Audio Options
-aframes number (output)
Set the number of audio frames to output. This is an obsolete alias for
"-frames:a", which you should use instead.

-ar[:stream_specifier] freq (input/output,per-stream)
Set the audio sampling frequency. For output streams it is set by de-
fault to the frequency of the corresponding input stream. For input
streams this option only makes sense for audio grabbing devices and raw
demuxers and is mapped to the corresponding demuxer options.

-aq q (output)
Set the audio quality (codec-specific, VBR). This is an alias for -q:a.

-ac[:stream_specifier] channels (input/output,per-stream)
Set the number of audio channels. For output streams it is set by de-
fault to the number of input audio channels. For input streams this op-
tion only makes sense for audio grabbing devices and raw demuxers and
is mapped to the corresponding demuxer options.

-an (input/output)
As an input option, blocks all audio streams of a file from being fil-
tered or being automatically selected or mapped for any output. See
"-discard" option to disable streams individually.

As an output option, disables audio recording i.e. automatic selection
or mapping of any audio stream. For full manual control see the "-map"
option.

-acodec codec (input/output)
Set the audio codec. This is an alias for "-codec:a".

-sample_fmt[:stream_specifier] sample_fmt (output,per-stream)
Set the audio sample format. Use "-sample_fmts" to get a list of sup-
ported sample formats.

-af filtergraph (output)
Create the filtergraph specified by filtergraph and use it to filter
the stream.

This is an alias for "-filter:a", see the -filter option.

Advanced Audio options
-atag fourcc/tag (output)
Force audio tag/fourcc. This is an alias for "-tag:a".

-ch_layout[:stream_specifier] layout (input/output,per-stream)
Alias for "-channel_layout".

-channel_layout[:stream_specifier] layout (input/output,per-stream)
Set the audio channel layout. For output streams it is set by default
to the input channel layout. For input streams it overrides the channel
layout of the input. Not all decoders respect the overridden channel
layout. This option also sets the channel layout for audio grabbing de-
vices and raw demuxers and is mapped to the corresponding demuxer op-
tion.

-guess_layout_max channels (input,per-stream)
If some input channel layout is not known, try to guess only if it cor-
responds to at most the specified number of channels. For example, 2
tells to ffmpeg to recognize 1 channel as mono and 2 channels as stereo
but not 6 channels as 5.1. The default is to always try to guess. Use 0
to disable all guessing. Using the "-channel_layout" option to explic-
itly specify an input layout also disables guessing.

Subtitle options
-scodec codec (input/output)
Set the subtitle codec. This is an alias for "-codec:s".

-sn (input/output)
As an input option, blocks all subtitle streams of a file from being
filtered or being automatically selected or mapped for any output. See
"-discard" option to disable streams individually.

As an output option, disables subtitle recording i.e. automatic selec-
tion or mapping of any subtitle stream. For full manual control see the
"-map" option.

Advanced Subtitle options
-fix_sub_duration
Fix subtitles durations. For each subtitle, wait for the next packet in
the same stream and adjust the duration of the first to avoid overlap.
This is necessary with some subtitles codecs, especially DVB subtitles,
because the duration in the original packet is only a rough estimate
and the end is actually marked by an empty subtitle frame. Failing to
use this option when necessary can result in exaggerated durations or
muxing failures due to non-monotonic timestamps.

Note that this option will delay the output of all data until the next
subtitle packet is decoded: it may increase memory consumption and la-
tency a lot.

-canvas_size size
Set the size of the canvas used to render subtitles.

Advanced options
-map [-]input_file_id[:stream_specifier][:view_specifier][:?] | [linklabel]
(output)
Create one or more streams in the output file. This option has two
forms for specifying the data source(s): the first selects one or more
streams from some input file (specified with "-i"), the second takes an
output from some complex filtergraph (specified with "-filter_com-
plex").

In the first form, an output stream is created for every stream from
the input file with the index input_file_id. If stream_specifier is
given, only those streams that match the specifier are used (see the
Stream specifiers section for the stream_specifier syntax).

A "-" character before the stream identifier creates a "negative" map-
ping. It disables matching streams from already created mappings.

An optional view_specifier may be given after the stream specifier,
which for multiview video specifies the view to be used. The view spec-
ifier may have one of the following formats:

view:view_id
select a view by its ID; view_id may be set to 'all' to use all the
views interleaved into one stream;

vidx:view_idx
select a view by its index; i.e. 0 is the base view, 1 is the first
non-base view, etc.

vpos:position
select a view by its display position; position may be "left" or
"right"

The default for transcoding is to only use the base view, i.e. the
equivalent of "vidx:0". For streamcopy, view specifiers are not sup-
ported and all views are always copied.

A trailing "?" after the stream index will allow the map to be op-
tional: if the map matches no streams the map will be ignored instead
of failing. Note the map will still fail if an invalid input file index
is used; such as if the map refers to a non-existent input.

An alternative [linklabel] form will map outputs from complex filter
graphs (see the -filter_complex option) to the output file. linklabel
must correspond to a defined output link label in the graph.

This option may be specified multiple times, each adding more streams
to the output file. Any given input stream may also be mapped any num-
ber of times as a source for different output streams, e.g. in order to
use different encoding options and/or filters. The streams are created
in the output in the same order in which the "-map" options are given
on the commandline.

Using this option disables the default mappings for this output file.

Examples:

map everything
To map ALL streams from the first input file to output

ffmpeg -i INPUT -map 0 output

select specific stream
If you have two audio streams in the first input file, these
streams are identified by 0:0 and 0:1. You can use "-map" to select
which streams to place in an output file. For example:

ffmpeg -i INPUT -map 0:1 out.wav

will map the second input stream in INPUT to the (single) output
stream in out.wav.

create multiple streams
To select the stream with index 2 from input file a.mov (specified
by the identifier 0:2), and stream with index 6 from input b.mov
(specified by the identifier 1:6), and copy them to the output file
out.mov:

ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov

create multiple streams 2
To select all video and the third audio stream from an input file:

ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT

negative map
To map all the streams except the second audio, use negative map-
pings

ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT

optional map
To map the video and audio streams from the first input, and using
the trailing "?", ignore the audio mapping if no audio streams ex-
ist in the first input:

ffmpeg -i INPUT -map 0:v -map 0:a? OUTPUT

map by language
To pick the English audio stream:

ffmpeg -i INPUT -map 0:m:language:eng OUTPUT

-ignore_unknown
Ignore input streams with unknown type instead of failing if copying
such streams is attempted.

-copy_unknown
Allow input streams with unknown type to be copied instead of failing
if copying such streams is attempted.

-map_metadata[:metadata_spec_out] infile[:metadata_spec_in] (out-
put,per-metadata)
Set metadata information of the next output file from infile. Note that
those are file indices (zero-based), not filenames. Optional meta-
data_spec_in/out parameters specify, which metadata to copy. A meta-
data specifier can have the following forms:

g global metadata, i.e. metadata that applies to the whole file

s[:stream_spec]
per-stream metadata. stream_spec is a stream specifier as described
in the Stream specifiers chapter. In an input metadata specifier,
the first matching stream is copied from. In an output metadata
specifier, all matching streams are copied to.

c:chapter_index
per-chapter metadata. chapter_index is the zero-based chapter in-
dex.

p:program_index
per-program metadata. program_index is the zero-based program in-
dex.

If metadata specifier is omitted, it defaults to global.

By default, global metadata is copied from the first input file,
per-stream and per-chapter metadata is copied along with streams/chap-
ters. These default mappings are disabled by creating any mapping of
the relevant type. A negative file index can be used to create a dummy
mapping that just disables automatic copying.

For example to copy metadata from the first stream of the input file to
global metadata of the output file:

ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3

To do the reverse, i.e. copy global metadata to all audio streams:

ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv

Note that simple 0 would work as well in this example, since global
metadata is assumed by default.

-map_chapters input_file_index (output)
Copy chapters from input file with index input_file_index to the next
output file. If no chapter mapping is specified, then chapters are
copied from the first input file with at least one chapter. Use a nega-
tive file index to disable any chapter copying.

-benchmark (global)
Show benchmarking information at the end of an encode. Shows real,
system and user time used and maximum memory consumption. Maximum mem-
ory consumption is not supported on all systems, it will usually dis-
play as 0 if not supported.

-benchmark_all (global)
Show benchmarking information during the encode. Shows real, system
and user time used in various steps (audio/video encode/decode).

-timelimit duration (global)
Exit after ffmpeg has been running for duration seconds in CPU user
time.

-dump (global)
Dump each input packet to stderr.

-hex (global)
When dumping packets, also dump the payload.

-readrate speed (input)
Limit input read speed.

Its value is a floating-point positive number which represents the max-
imum duration of media, in seconds, that should be ingested in one sec-
ond of wallclock time. Default value is zero and represents no imposed
limitation on speed of ingestion. Value 1 represents real-time speed
and is equivalent to "-re".

Mainly used to simulate a capture device or live input stream (e.g.
when reading from a file). Should not be used with a low value when
input is an actual capture device or live stream as it may cause packet
loss.

It is useful for when flow speed of output packets is important, such
as live streaming.

-re (input)
Read input at native frame rate. This is equivalent to setting "-read-
rate 1".

-readrate_initial_burst seconds
Set an initial read burst time, in seconds, after which -re/-readrate
will be enforced.

-readrate_catchup speed (input)
If either the input or output is blocked leading to actual read speed
falling behind the specified readrate, then this rate takes effect till
the input catches up with the specified readrate. Must not be lower
than the primary readrate.

-vsync parameter (global)
-fps_mode[:stream_specifier] parameter (output,per-stream)
Set video sync method / framerate mode. vsync is applied to all output
video streams but can be overridden for a stream by setting fps_mode.
vsync is deprecated and will be removed in the future.

For compatibility reasons some of the values for vsync can be specified
as numbers (shown in parentheses in the following table).

passthrough (0)
Each frame is passed with its timestamp from the demuxer to the
muxer.

cfr (1)
Frames will be duplicated and dropped to achieve exactly the re-
quested constant frame rate.

vfr (2)
Frames are passed through with their timestamp or dropped so as to
prevent 2 frames from having the same timestamp.

auto (-1)
Chooses between cfr and vfr depending on muxer capabilities. This
is the default method.

Note that the timestamps may be further modified by the muxer, after
this. For example, in the case that the format option avoid_nega-
tive_ts is enabled.

With -map you can select from which stream the timestamps should be
taken. You can leave either video or audio unchanged and sync the re-
maining stream(s) to the unchanged one.

-frame_drop_threshold parameter
Frame drop threshold, which specifies how much behind video frames can
be before they are dropped. In frame rate units, so 1.0 is one frame.
The default is -1.1. One possible usecase is to avoid framedrops in
case of noisy timestamps or to increase frame drop precision in case of
exact timestamps.

-apad parameters (output,per-stream)
Pad the output audio stream(s). This is the same as applying "-af
apad". Argument is a string of filter parameters composed the same as
with the "apad" filter. "-shortest" must be set for this output for
the option to take effect.

-copyts
Do not process input timestamps, but keep their values without trying
to sanitize them. In particular, do not remove the initial start time
offset value.

Note that, depending on the vsync option or on specific muxer process-
ing (e.g. in case the format option avoid_negative_ts is enabled) the
output timestamps may mismatch with the input timestamps even when this
option is selected.

-start_at_zero
When used with copyts, shift input timestamps so they start at zero.

This means that using e.g. "-ss 50" will make output timestamps start
at 50 seconds, regardless of what timestamp the input file started at.

-copytb mode
Specify how to set the encoder timebase when stream copying. mode is
an integer numeric value, and can assume one of the following values:

1 Use the demuxer timebase.

The time base is copied to the output encoder from the correspond-
ing input demuxer. This is sometimes required to avoid non monoton-
ically increasing timestamps when copying video streams with vari-
able frame rate.

0 Use the decoder timebase.

The time base is copied to the output encoder from the correspond-
ing input decoder.

-1 Try to make the choice automatically, in order to generate a sane
output.

Default value is -1.

-enc_time_base[:stream_specifier] timebase (output,per-stream)
Set the encoder timebase. timebase can assume one of the following val-
ues:

0 Assign a default value according to the media type.

For video - use 1/framerate, for audio - use 1/samplerate.

demux
Use the timebase from the demuxer.

filter
Use the timebase from the filtergraph.

a positive number
Use the provided number as the timebase.

This field can be provided as a ratio of two integers (e.g. 1:24,
1:48000) or as a decimal number (e.g. 0.04166, 2.0833e-5)

Default value is 0.

-bitexact (input/output)
Enable bitexact mode for (de)muxer and (de/en)coder

-shortest (output)
Finish encoding when the shortest output stream ends.

Note that this option may require buffering frames, which introduces
extra latency. The maximum amount of this latency may be controlled
with the "-shortest_buf_duration" option.

-shortest_buf_duration duration (output)
The "-shortest" option may require buffering potentially large amounts
of data when at least one of the streams is "sparse" (i.e. has large
gaps between frames a this is typically the case for subtitles).

This option controls the maximum duration of buffered frames in sec-
onds. Larger values may allow the "-shortest" option to produce more
accurate results, but increase memory use and latency.

The default value is 10 seconds.

-dts_delta_threshold threshold
Timestamp discontinuity delta threshold, expressed as a decimal number
of seconds.

The timestamp discontinuity correction enabled by this option is only
applied to input formats accepting timestamp discontinuity (for which
the "AVFMT_TS_DISCONT" flag is enabled), e.g. MPEG-TS and HLS, and is
automatically disabled when employing the "-copyts" option (unless
wrapping is detected).

If a timestamp discontinuity is detected whose absolute value is
greater than threshold, ffmpeg will remove the discontinuity by de-
creasing/increasing the current DTS and PTS by the corresponding delta
value.

The default value is 10.

-dts_error_threshold threshold
Timestamp error delta threshold, expressed as a decimal number of sec-
onds.

The timestamp correction enabled by this option is only applied to in-
put formats not accepting timestamp discontinuity (for which the
"AVFMT_TS_DISCONT" flag is not enabled).

If a timestamp discontinuity is detected whose absolute value is
greater than threshold, ffmpeg will drop the PTS/DTS timestamp value.

The default value is "3600*30" (30 hours), which is arbitrarily picked
and quite conservative.

-muxdelay seconds (output)
Set the maximum demux-decode delay.

-muxpreload seconds (output)
Set the initial demux-decode delay.

-streamid output-stream-index:new-value (output)
Assign a new stream-id value to an output stream. This option should be
specified prior to the output filename to which it applies. For the
situation where multiple output files exist, a streamid may be reas-
signed to a different value.

For example, to set the stream 0 PID to 33 and the stream 1 PID to 36
for an output mpegts file:

ffmpeg -i inurl -streamid 0:33 -streamid 1:36 out.ts

-bsf[:stream_specifier] bitstream_filters (input/output,per-stream)
Apply bitstream filters to matching streams. The filters are applied to
each packet as it is received from the demuxer (when used as an input
option) or before it is sent to the muxer (when used as an output op-
tion).

bitstream_filters is a comma-separated list of bitstream filter speci-
fications, each of the form

<filter>[=<optname0>=<optval0>:<optname1>=<optval1>:...]

Any of the ',=:' characters that are to be a part of an option value
need to be escaped with a backslash.

Use the "-bsfs" option to get the list of bitstream filters.

E.g.

ffmpeg -bsf:v h264_mp4toannexb -i h264.mp4 -c:v copy -an out.h264

applies the "h264_mp4toannexb" bitstream filter (which converts MP4-en-
capsulated H.264 stream to Annex B) to the input video stream.

On the other hand,

ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt

applies the "mov2textsub" bitstream filter (which extracts text from
MOV subtitles) to the output subtitle stream. Note, however, that since
both examples use "-c copy", it matters little whether the filters are
applied on input or output - that would change if transcoding was hap-
pening.

-tag[:stream_specifier] codec_tag (input/output,per-stream)
Force a tag/fourcc for matching streams.

-timecode hh:mm:ssSEPff
Specify Timecode for writing. SEP is ':' for non drop timecode and ';'
(or '.') for drop.

ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg

-filter_complex filtergraph (global)
Define a complex filtergraph, i.e. one with arbitrary number of inputs
and/or outputs. For simple graphs -- those with one input and one out-
put of the same type -- see the -filter options. filtergraph is a de-
scription of the filtergraph, as described in the ``Filtergraph syn-
tax'' section of the ffmpeg-filters manual. This option may be speci-
fied multiple times - each use creates a new complex filtergraph.

Inputs to a complex filtergraph may come from different source types,
distinguished by the format of the corresponding link label:

* To connect an input stream, use "[file_index:stream_specifier]"
(i.e. the same syntax as -map). If stream_specifier matches multi-
ple streams, the first one will be used. For multiview video, the
stream specifier may be followed by the view specifier, see docu-
mentation for the -map option for its syntax.

* To connect a loopback decoder use [dec:dec_idx], where dec_idx is
the index of the loopback decoder to be connected to given input.
For multiview video, the decoder index may be followed by the view
specifier, see documentation for the -map option for its syntax.

* To connect an output from another complex filtergraph, use its link
label. E.g the following example:

ffmpeg -i input.mkv \
-filter_complex '[0:v]scale=size=hd1080,split=outputs=2[for_enc][orig_scaled]' \
-c:v libx264 -map '[for_enc]' output.mkv \
-dec 0:0 \
-filter_complex '[dec:0][orig_scaled]hstack[stacked]' \
-map '[stacked]' -c:v ffv1 comparison.mkv

reads an input video and

* (line 2) uses a complex filtergraph with one input and two out-
puts to scale the video to 1920x1080 and duplicate the result
to both outputs;

* (line 3) encodes one scaled output with "libx264" and writes
the result to output.mkv;

* (line 4) decodes this encoded stream with a loopback decoder;

* (line 5) places the output of the loopback decoder (i.e. the
"libx264"-encoded video) side by side with the scaled original
input;

* (line 6) combined video is then losslessly encoded and written
into comparison.mkv.

Note that the two filtergraphs cannot be combined into one, because
then there would be a cycle in the transcoding pipeline (filter-
graph output goes to encoding, from there to decoding, then back to
the same graph), and such cycles are not allowed.

An unlabeled input will be connected to the first unused input stream
of the matching type.

Output link labels are referred to with -map. Unlabeled outputs are
added to the first output file.

Note that with this option it is possible to use only lavfi sources
without normal input files.

For example, to overlay an image over video

ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map
'[out]' out.mkv

Here "[0:v]" refers to the first video stream in the first input file,
which is linked to the first (main) input of the overlay filter. Simi-
larly the first video stream in the second input is linked to the sec-
ond (overlay) input of overlay.

Assuming there is only one video stream in each input file, we can omit
input labels, so the above is equivalent to

ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map
'[out]' out.mkv

Furthermore we can omit the output label and the single output from the
filter graph will be added to the output file automatically, so we can
simply write

ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv

As a special exception, you can use a bitmap subtitle stream as input:
it will be converted into a video with the same size as the largest
video in the file, or 720x576 if no video is present. Note that this is
an experimental and temporary solution. It will be removed once libav-
filter has proper support for subtitles.

For example, to hardcode subtitles on top of a DVB-T recording stored
in MPEG-TS format, delaying the subtitles by 1 second:

ffmpeg -i input.ts -filter_complex \
'[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \
-sn -map '#0x2dc' output.mkv

(0x2d0, 0x2dc and 0x2ef are the MPEG-TS PIDs of respectively the video,
audio and subtitles streams; 0:0, 0:3 and 0:7 would have worked too)

To generate 5 seconds of pure red video using lavfi "color" source:

ffmpeg -filter_complex 'color=c=red' -t 5 out.mkv

-filter_complex_threads nb_threads (global)
Defines how many threads are used to process a filter_complex graph.
Similar to filter_threads but used for "-filter_complex" graphs only.
The default is the number of available CPUs.

-lavfi filtergraph (global)
Define a complex filtergraph, i.e. one with arbitrary number of inputs
and/or outputs. Equivalent to -filter_complex.

-accurate_seek (input)
This option enables or disables accurate seeking in input files with
the -ss option. It is enabled by default, so seeking is accurate when
transcoding. Use -noaccurate_seek to disable it, which may be useful
e.g. when copying some streams and transcoding the others.

-seek_timestamp (input)
This option enables or disables seeking by timestamp in input files
with the -ss option. It is disabled by default. If enabled, the argu-
ment to the -ss option is considered an actual timestamp, and is not
offset by the start time of the file. This matters only for files which
do not start from timestamp 0, such as transport streams.

-thread_queue_size size (input/output)
For input, this option sets the maximum number of queued packets when
reading from the file or device. With low latency / high rate live
streams, packets may be discarded if they are not read in a timely man-
ner; setting this value can force ffmpeg to use a separate input thread
and read packets as soon as they arrive. By default ffmpeg only does
this if multiple inputs are specified.

For output, this option specified the maximum number of packets that
may be queued to each muxing thread.

-sdp_file file (global)
Print sdp information for an output stream to file. This allows dump-
ing sdp information when at least one output isn't an rtp stream. (Re-
quires at least one of the output formats to be rtp).

-discard (input)
Allows discarding specific streams or frames from streams. Any input
stream can be fully discarded, using value "all" whereas selective dis-
carding of frames from a stream occurs at the demuxer and is not sup-
ported by all demuxers.

noneDiscard no frame.

default
Default, which discards no frames.

noref
Discard all non-reference frames.

bidir
Discard all bidirectional frames.

nokey
Discard all frames excepts keyframes.

all Discard all frames.

-abort_on flags (global)
Stop and abort on various conditions. The following flags are avail-
able:

empty_output
No packets were passed to the muxer, the output is empty.

empty_output_stream
No packets were passed to the muxer in some of the output streams.

-max_error_rate (global)
Set fraction of decoding frame failures across all inputs which when
crossed ffmpeg will return exit code 69. Crossing this threshold does
not terminate processing. Range is a floating-point number between 0 to
1. Default is 2/3.

-xerror (global)
Stop and exit on error

-max_muxing_queue_size packets (output,per-stream)
When transcoding audio and/or video streams, ffmpeg will not begin
writing into the output until it has one packet for each such stream.
While waiting for that to happen, packets for other streams are
buffered. This option sets the size of this buffer, in packets, for the
matching output stream.

The default value of this option should be high enough for most uses,
so only touch this option if you are sure that you need it.

-muxing_queue_data_threshold bytes (output,per-stream)
This is a minimum threshold until which the muxing queue size is not
taken into account. Defaults to 50 megabytes per stream, and is based
on the overall size of packets passed to the muxer.

-auto_conversion_filters (global)
Enable automatically inserting format conversion filters in all filter
graphs, including those defined by -vf, -af, -filter_complex and
-lavfi. If filter format negotiation requires a conversion, the ini-
tialization of the filters will fail. Conversions can still be per-
formed by inserting the relevant conversion filter (scale, aresample)
in the graph. On by default, to explicitly disable it you need to
specify "-noauto_conversion_filters".

-bits_per_raw_sample[:stream_specifier] value (output,per-stream)
Declare the number of bits per raw sample in the given output stream to
be value. Note that this option sets the information provided to the
encoder/muxer, it does not change the stream to conform to this value.
Setting values that do not match the stream properties may result in
encoding failures or invalid output files.

-stats_enc_pre[:stream_specifier] path (output,per-stream)
-stats_enc_post[:stream_specifier] path (output,per-stream)
-stats_mux_pre[:stream_specifier] path (output,per-stream)
Write per-frame encoding information about the matching streams into
the file given by path.

-stats_enc_pre writes information about raw video or audio frames right
before they are sent for encoding, while -stats_enc_post writes infor-
mation about encoded packets as they are received from the encoder.
-stats_mux_pre writes information about packets just as they are about
to be sent to the muxer. Every frame or packet produces one line in the
specified file. The format of this line is controlled by
-stats_enc_pre_fmt / -stats_enc_post_fmt / -stats_mux_pre_fmt.

When stats for multiple streams are written into a single file, the
lines corresponding to different streams will be interleaved. The pre-
cise order of this interleaving is not specified and not guaranteed to
remain stable between different invocations of the program, even with
the same options.

-stats_enc_pre_fmt[:stream_specifier] format_spec (output,per-stream)
-stats_enc_post_fmt[:stream_specifier] format_spec (output,per-stream)
-stats_mux_pre_fmt[:stream_specifier] format_spec (output,per-stream)
Specify the format for the lines written with -stats_enc_pre /
-stats_enc_post / -stats_mux_pre.

format_spec is a string that may contain directives of the form {fmt}.
format_spec is backslash-escaped --- use \{, \}, and \\ to write a lit-
eral {, }, or \, respectively, into the output.

The directives given with fmt may be one of the following:

fidxIndex of the output file.

sidxIndex of the output stream in the file.

n Frame number. Pre-encoding: number of frames sent to the encoder so
far. Post-encoding: number of packets received from the encoder so
far. Muxing: number of packets submitted to the muxer for this
stream so far.

ni Input frame number. Index of the input frame (i.e. output by a de-
coder) that corresponds to this output frame or packet. -1 if un-
available.

tb Timebase in which this frame/packet's timestamps are expressed, as
a rational number num/den. Note that encoder and muxer may use dif-
ferent timebases.

tbi Timebase for ptsi, as a rational number num/den. Available when
ptsi is available, 0/1 otherwise.

pts Presentation timestamp of the frame or packet, as an integer.
Should be multiplied by the timebase to compute presentation time.

ptsiPresentation timestamp of the input frame (see ni), as an integer.
Should be multiplied by tbi to compute presentation time. Printed
as (2^63 - 1 = 9223372036854775807) when not available.

t Presentation time of the frame or packet, as a decimal number.
Equal to pts multiplied by tb.

ti Presentation time of the input frame (see ni), as a decimal number.
Equal to ptsi multiplied by tbi. Printed as inf when not available.

dts (packet)
Decoding timestamp of the packet, as an integer. Should be multi-
plied by the timebase to compute presentation time.

dt (packet)
Decoding time of the frame or packet, as a decimal number. Equal to
dts multiplied by tb.

sn (frame,audio)
Number of audio samples sent to the encoder so far.

samp (frame,audio)
Number of audio samples in the frame.

size (packet)
Size of the encoded packet in bytes.

br (packet)
Current bitrate in bits per second.

abr (packet)
Average bitrate for the whole stream so far, in bits per second, -1
if it cannot be determined at this point.

key (packet)
Character 'K' if the packet contains a keyframe, character 'N' oth-
erwise.

Directives tagged with packet may only be used with -stats_enc_post_fmt
and -stats_mux_pre_fmt.

Directives tagged with frame may only be used with -stats_enc_pre_fmt.

Directives tagged with audio may only be used with audio streams.

The default format strings are:

pre-encoding
{fidx} {sidx} {n} {t}

post-encoding
{fidx} {sidx} {n} {t}

In the future, new items may be added to the end of the default format-
ting strings. Users who depend on the format staying exactly the same,
should prescribe it manually.

Note that stats for different streams written into the same file may
have different formats.

Preset files
A preset file contains a sequence of option=value pairs, one for each line,
specifying a sequence of options which would be awkward to specify on the
command line. Lines starting with the hash ('#') character are ignored and
are used to provide comments. Check the presets directory in the FFmpeg
source tree for examples.

There are two types of preset files: ffpreset and avpreset files.

ffpreset files

ffpreset files are specified with the "vpre", "apre", "spre", and "fpre"
options. The "fpre" option takes the filename of the preset instead of a
preset name as input and can be used for any kind of codec. For the "vpre",
"apre", and "spre" options, the options specified in a preset file are ap-
plied to the currently selected codec of the same type as the preset op-
tion.

The argument passed to the "vpre", "apre", and "spre" preset options iden-
tifies the preset file to use according to the following rules:

First ffmpeg searches for a file named arg.ffpreset in the directories
$FFMPEG_DATADIR (if set), and $HOME/.ffmpeg, and in the datadir defined at
configuration time (usually PREFIX/share/ffmpeg) or in a ffpresets folder
along the executable on win32, in that order. For example, if the argument
is "libvpx-1080p", it will search for the file libvpx-1080p.ffpreset.

If no such file is found, then ffmpeg will search for a file named
codec_name-arg.ffpreset in the above-mentioned directories, where
codec_name is the name of the codec to which the preset file options will
be applied. For example, if you select the video codec with "-vcodec lib-
vpx" and use "-vpre 1080p", then it will search for the file lib-
vpx-1080p.ffpreset.

avpreset files

avpreset files are specified with the "pre" option. They work similar to
ffpreset files, but they only allow encoder- specific options. Therefore,
an option=value pair specifying an encoder cannot be used.

When the "pre" option is specified, ffmpeg will look for files with the
suffix .avpreset in the directories $AVCONV_DATADIR (if set), and
$HOME/.avconv, and in the datadir defined at configuration time (usually
PREFIX/share/ffmpeg), in that order.

First ffmpeg searches for a file named codec_name-arg.avpreset in the
above-mentioned directories, where codec_name is the name of the codec to
which the preset file options will be applied. For example, if you select
the video codec with "-vcodec libvpx" and use "-pre 1080p", then it will
search for the file libvpx-1080p.avpreset.

If no such file is found, then ffmpeg will search for a file named arg.avp-
reset in the same directories.

vstats file format
The "-vstats" and "-vstats_file" options enable generation of a file con-
taining statistics about the generated video outputs.

The "-vstats_version" option controls the format version of the generated
file.

With version 1 the format is:

frame= <FRAME> q= <FRAME_QUALITY> PSNR= <PSNR> f_size= <FRAME_SIZE> s_size= <STREAM_SIZE>kB time= <TIMESTAMP> br= <BITRATE>kbits/s avg_br= <AVERAGE_BITRATE>kbits/s

With version 2 the format is:

out= <OUT_FILE_INDEX> st= <OUT_FILE_STREAM_INDEX> frame= <FRAME_NUMBER> q= <FRAME_QUALITY>f PSNR= <PSNR> f_size= <FRAME_SIZE> s_size= <STREAM_SIZE>kB time= <TIMESTAMP> br= <BITRATE>kbits/s avg_br= <AVERAGE_BITRATE>kbits/s

The value corresponding to each key is described below:

avg_br
average bitrate expressed in Kbits/s

br bitrate expressed in Kbits/s

frame
number of encoded frame

out out file index

PSNRPeak Signal to Noise Ratio

q quality of the frame

f_size
encoded packet size expressed as number of bytes

s_size
stream size expressed in KiB

st out file stream index

timetime of the packet

typepicture type

See also the -stats_enc options for an alternative way to show encoding
statistics.

EXAMPLES
Video and Audio grabbing
If you specify the input format and device then ffmpeg can grab video and
audio directly.

ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg

Or with an ALSA audio source (mono input, card id 1) instead of OSS:

ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg

Note that you must activate the right video source and channel before
launching ffmpeg with any TV viewer such as <http://linux.byte-
sex.org/xawtv/> by Gerd Knorr. You also have to set the audio recording
levels correctly with a standard mixer.

X11 grabbing
Grab the X11 display with ffmpeg via

ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0 /tmp/out.mpg

0.0 is display.screen number of your X11 server, same as the DISPLAY envi-
ronment variable.

ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0+10,20 /tmp/out.mpg

0.0 is display.screen number of your X11 server, same as the DISPLAY envi-
ronment variable. 10 is the x-offset and 20 the y-offset for the grabbing.

Video and Audio file format conversion
Any supported file format and protocol can serve as input to ffmpeg:

Examples:

* You can use YUV files as input:

ffmpeg -i /tmp/test%d.Y /tmp/out.mpg

It will use the files:

/tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
/tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...

The Y files use twice the resolution of the U and V files. They are raw
files, without header. They can be generated by all decent video de-
coders. You must specify the size of the image with the -s option if
ffmpeg cannot guess it.

* You can input from a raw YUV420P file:

ffmpeg -i /tmp/test.yuv /tmp/out.avi

test.yuv is a file containing raw YUV planar data. Each frame is com-
posed of the Y plane followed by the U and V planes at half vertical
and horizontal resolution.

* You can output to a raw YUV420P file:

ffmpeg -i mydivx.avi hugefile.yuv

* You can set several input files and output files:

ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg

Converts the audio file a.wav and the raw YUV video file a.yuv to MPEG
file a.mpg.

* You can also do audio and video conversions at the same time:

ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2

Converts a.wav to MPEG audio at 22050 Hz sample rate.

* You can encode to several formats at the same time and define a mapping
from input stream to output streams:

ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2

Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
file:index' specifies which input stream is used for each output
stream, in the order of the definition of output streams.

* You can transcode decrypted VOBs:

ffmpeg -i snatch_1.vob -f avi -c:v mpeg4 -b:v 800k -g 300 -bf 2 -c:a libmp3lame -b:a 128k snatch.avi

This is a typical DVD ripping example; the input is a VOB file, the
output an AVI file with MPEG-4 video and MP3 audio. Note that in this
command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
GOP size is 300 which means one intra frame every 10 seconds for
29.97fps input video. Furthermore, the audio stream is MP3-encoded so
you need to enable LAME support by passing "--enable-libmp3lame" to
configure. The mapping is particularly useful for DVD transcoding to
get the desired audio language.

NOTE: To see the supported input formats, use "ffmpeg -demuxers".

* You can extract images from a video, or create a video from many im-
ages:

For extracting images from a video:

ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg

This will extract one video frame per second from the video and will
output them in files named foo-001.jpeg, foo-002.jpeg, etc. Images will
be rescaled to fit the new WxH values.

If you want to extract just a limited number of frames, you can use the
above command in combination with the "-frames:v" or "-t" option, or in
combination with -ss to start extracting from a certain point in time.

For creating a video from many images:

ffmpeg -f image2 -framerate 12 -i foo-%03d.jpeg -s WxH foo.avi

The syntax "foo-%03d.jpeg" specifies to use a decimal number composed
of three digits padded with zeroes to express the sequence number. It
is the same syntax supported by the C printf function, but only formats
accepting a normal integer are suitable.

When importing an image sequence, -i also supports expanding shell-like
wildcard patterns (globbing) internally, by selecting the image2-spe-
cific "-pattern_type glob" option.

For example, for creating a video from filenames matching the glob pat-
tern "foo-*.jpeg":

ffmpeg -f image2 -pattern_type glob -framerate 12 -i 'foo-*.jpeg' -s WxH foo.avi

* You can put many streams of the same type in the output:

ffmpeg -i test1.avi -i test2.avi -map 1:1 -map 1:0 -map 0:1 -map 0:0 -c copy -y test12.nut

The resulting output file test12.nut will contain the first four
streams from the input files in reverse order.

* To force CBR video output:

ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v

* The four options lmin, lmax, mblmin and mblmax use 'lambda' units, but
you may use the QP2LAMBDA constant to easily convert from 'q' units:

ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext

SEE ALSO
ffmpeg-all(1), ffplay(1), ffprobe(1), ffmpeg-utils(1), ffmpeg-scaler(1),
ffmpeg-resampler(1), ffmpeg-codecs(1), ffmpeg-bitstream-filters(1), ffm-
peg-formats(1), ffmpeg-devices(1), ffmpeg-protocols(1), ffmpeg-filters(1)

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.

FFMPEG(1)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=ffmpeg&sektion=1&manpath=FreeBSD+15.1-RELEASE+and+Ports>

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