Sortix 1.1dev ports manual
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FFMPEG(1) | FFMPEG(1) |
NAME
ffmpeg - ffmpeg video converterSYNOPSIS
ffmpeg [ global_options] {[input_file_options] -i input_url} ... {[ output_file_options] output_url} ...DESCRIPTION
ffmpeg is a very fast video and audio converter that can also grab from a live audio/video source. It can also convert between arbitrary sample rates and resize video on the fly with a high quality polyphase filter. ffmpeg reads from an arbitrary number of input "files" (which can be regular files, pipes, network streams, grabbing devices, etc.), specified by the "-i" option, and writes to an arbitrary number of output "files", which are specified 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 url can, in principle, contain any number of streams of different types (video/audio/subtitle/attachment/data). The allowed number and/or types of streams may be limited by the container format. Selecting which streams from which inputs will go into which output is either done automatically or with the "-map" option (see the Stream selection chapter). To refer to input files in options, you must use their indices (0-based). E.g. the first input file is 0, the second is 1, etc. Similarly, streams within a file are referred to by their indices. E.g. "2:3" refers to the fourth stream in the third input file. Also see the Stream specifiers chapter. As a general rule, options are applied to the next specified file. Therefore, 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. verbosity 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 between files.- •
- To set the video bitrate of the output file to 64 kbit/s:
ffmpeg -i input.avi -b:v 64k -bufsize 64k output.avi
- •
- To force the frame rate of the output file to 24 fps:
ffmpeg -i input.avi -r 24 output.avi
- •
- To 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.avi
DETAILED DESCRIPTION
The transcoding process in ffmpeg for each output can be described by the following diagram:_______ ______________ | | | | | input | demuxer | encoded data | decoder | file | ---------> | packets | -----+ |_______| |______________| | v _________ | | | decoded | | frames | |_________| ________ ______________ | | | | | | | output | <-------- | encoded data | <----+ | file | muxer | packets | encoder |________| |______________|ffmpeg calls the libavformat library (containing demuxers) to read input files and get packets containing encoded data from them. When there are multiple input files, ffmpeg tries to keep them synchronized by tracking lowest timestamp on any active input stream. Encoded packets are then passed to the decoder (unless streamcopy is selected for the stream, see further for a description). The decoder produces uncompressed frames (raw video/PCM audio/...) which can be processed further by filtering (see next section). After filtering, the frames are passed to the encoder, which encodes them and outputs encoded packets. Finally those are passed to the muxer, which writes the encoded packets to the output file.
Filtering
Before encoding, ffmpeg can process raw audio and video frames using filters from the libavfilter library. Several chained filters form a filter graph. ffmpeg distinguishes between two types of filtergraphs: simple and complex. Simple filtergraphs Simple filtergraphs are those that have exactly one input and output, both of the same type. In the above diagram they can be represented by simply inserting an additional step between decoding and encoding:_________ ______________ | | | | | decoded | | encoded data | | frames |\ _ | packets | |_________| \ /||______________| \ __________ / simple _\|| | / encoder filtergraph | filtered |/ | frames | |__________|Simple filtergraphs are configured with the per-stream -filter option (with -vf and -af aliases for video and audio respectively). A simple filtergraph for video can look for example like this:
_______ _____________ _______ ________ | | | | | | | | | input | ---> | deinterlace | ---> | scale | ---> | output | |_______| |_____________| |_______| |________|Note that some filters change frame properties but not frame contents. E.g. the "fps" filter in the example above changes number of frames, but does not touch the frame contents. Another example is the "setpts" filter, which only sets timestamps and otherwise passes the frames unchanged. 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. They can be represented with the following diagram:
_________ | | | input 0 |\ __________ |_________| \ | | \ _________ /| output 0 | \ | | / |__________| _________ \| complex | / | | | |/ | input 1 |---->| filter |\ |_________| | | \ __________ /| graph | \ | | / | | \| output 1 | _________ / |_________| |__________| | | / | input 2 |/ |_________|Complex filtergraphs are configured with the -filter_complex option. Note that this option is global, since a complex filtergraph, by its nature, cannot be unambiguously associated with a single stream or file. The -lavfi option is equivalent to -filter_complex. 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.
Stream copy
Stream copy is a mode selected by supplying the "copy" parameter to the -codec option. It makes ffmpeg omit the decoding and encoding step for the specified stream, so it does only demuxing and muxing. It is useful for changing the container format or modifying container-level metadata. The diagram above will, in this case, simplify to this:_______ ______________ ________ | | | | | | | input | demuxer | encoded data | muxer | output | | file | ---------> | packets | -------> | file | |_______| |______________| |________|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 many factors. Applying filters is obviously also impossible, since filters work on uncompressed data.
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 program, 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 inspects 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.
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.movThere are three output files specified, and for the first two, no "-map" options are set, so ffmpeg will select streams for these two files automatically. 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 selected. 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 encoders 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 occur. 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.mkvAlthough 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 Matroska 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" disables 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.srtA 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 label and so is sent to the first output file out1.mp4. Due to this, automatic 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.mkvThe 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.mkvThis 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.mkvThe 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 output isn't labelled, so it is sent to the first output file out1.mp4, regardless 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 determined 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 representing 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 interpreted 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 multiplies 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 corresponding 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.Stream specifiers
Some options are applied per-stream, e.g. bitrate or codec. Stream specifiers 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 program ID is also specified. In this case it is based on the ordering of the streams in the 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 attached pictures, video thumbnails or cover arts. If additional_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.
- p:program_id[:additional_stream_specifier]
- Matches streams which are in the program with the id program_id. If additional_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.
- 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.
Generic options
These options are shared amongst the ff* tools.- -L
- 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.
- long
- Print advanced tool options in addition to the basic tool options.
- full
- Print complete list of options, including shared and private options 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 name filter_name. Use the -filters option to get a list of all filters.
- bsf=bitstream_filter_name
- Print detailed information about the bitstream filter name bitstream_filter_name. Use the -bsfs option to get a list of all bitstream filters.
- -version
- Show version.
- -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.
- -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.
- -colors
- Show recognized color names.
- -sources device[,opt1=val1[,opt2=val2]...]
- Show autodetected sources of the input device. Some devices
may provide 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.
- 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.
- 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 incorrect 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
ffmpeg -loglevel repeat+level+verbose -i input output
ffmpeg [...] -loglevel +repeat
- -report
- Dump full command line and log output to a file named
" program-YYYYMMDD-HHMMSS.log" in the
current directory. This file can be useful for bug reports. It also
implies "-loglevel debug".
- file
- set 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").
FFREPORT=file=ffreport.log:level=32 ffmpeg -i input output
- -hide_banner
- Suppress printing banner.
- -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 ...
- 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
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/devices/codecs.
ffmpeg -i input.flac -id3v2_version 3 out.mp3All 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.mp4In the above example, a multichannel audio stream is mapped twice for output. 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 -option 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 output 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.
- -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 indicate that the stream is not to be
re-encoded.
ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT
ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT
- -t duration (input/output)
- When used as an input option (before "-i"), limit
the duration of data read from the input file.
- -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.
- -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 discarded. When doing stream copy or
when -noaccurate_seek is used, it will be preserved.
- -sseof position (input)
- Like the "-ss" option but relative to the "end of file". That is negative values are earlier in the file, 0 is at EOF.
- -itsoffset offset (input)
- Set the input time 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.
- -metadata[:metadata_specifier] key=value (output,per-metadata)
- Set a metadata key/value pair.
ffmpeg -i in.avi -metadata title="my title" out.flv
ffmpeg -i INPUT -metadata:s:a:0 language=eng OUTPUT
- -disposition[:stream_specifier] value ( output,per-stream)
- Sets the disposition for a stream.
- default
- dub
- original
- comment
- lyrics
- karaoke
- forced
- hearing_impaired
- visual_impaired
- clean_effects
- attached_pic
- captions
- descriptions
- dependent
- metadata
ffmpeg -i in.mkv -c copy -disposition:a:1 default out.mkv
ffmpeg -i in.mkv -c copy -disposition:s:0 0 -disposition:s:1 default out.mkv
ffmpeg -i in.mp4 -i IMAGE -map 0 -map 1 -c copy -c:v:1 png -disposition:v:1 attached_pic out.mp4
- -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.
- -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
ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
- -dn (input/output)
- As an input option, blocks all data streams of a file from
being filtered or being automatically selected or mapped for any output.
See "-discard" option to disable streams individually.
- -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-dependent. If qscale is used without a stream_specifier then it applies only to the video stream, this is to maintain compatibility with previous behavior and as specifying the same codec specific value to 2 different 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.
- -filter_script[:stream_specifier] filename (output,per-stream)
- This option is similar to -filter, the only difference is that its argument is the name of the file from which a filtergraph description is to be read.
- -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.
- -pre[:stream_specifier] preset_name (output,per-stream)
- Specify the preset for matching stream(s).
- -stats (global)
- Print encoding progress/statistics. It is on by default, to explicitly disable it you need to specify "-nostats".
- -progress url (global)
- Send program-friendly progress information to url.
- -stdin
- Enable interaction on standard input. On by default unless
standard input is used as an input. To explicitly disable interaction you
need to specify "-nostdin".
- -debug_ts (global)
- Print timestamp 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
employed by portable scripts.
- -attach filename (output)
- Add an attachment to the output file. This is supported by
a few formats like Matroska for e.g. fonts used in rendering subtitles.
Attachments 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
options 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).
ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv
- -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.
ffmpeg -dump_attachment:t:0 out.ttf -i INPUT
ffmpeg -dump_attachment:t "" -i INPUT
- -noautorotate
- Disable automatically rotating video based on file metadata.
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).
- -s[:stream_specifier] size ( input/output,per-stream)
- Set frame size.
- -aspect[:stream_specifier] aspect (output,per-stream)
- Set the video display aspect ratio specified by
aspect.
- -vn (input/output)
- As an input option, blocks all video streams of a file from
being filtered or being automatically selected or mapped for any output.
See "-discard" option to disable streams individually.
- -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 encoding. 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
bitrate. 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 prefix 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.
Advanced Video options
- -pix_fmt[:stream_specifier] format (input/output,per-stream)
- Set pixel format. Use "-pix_fmts" to show all the supported pixel formats. If the selected pixel format can not be selected, ffmpeg will print a warning and select the best pixel format supported by the encoder. If pix_fmt is prefixed by a "+", ffmpeg will exit with an error if the requested pixel format can not be selected, and automatic conversions 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 SwScaler flags.
- -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 beginning and end frame numbers, last one is quantizer to use if positive, or quality factor if negative.
- -ilme
- Force interlacing support in encoder (MPEG-2 and MPEG-4 only). Use this option if your input file is interlaced and you want to keep the interlaced format for minimum losses. The alternative is to deinterlace the input stream with -deinterlace, but deinterlacing introduces losses.
- -psnr
- Calculate PSNR of compressed frames.
- -vstats
- Dump video coding statistics to vstats_HHMMSS.log.
- -vstats_file file
- Dump video coding statistics to file.
- -vstats_version file
- Specifies which version of the vstats format to use.
Default is 2.
- -top[:stream_specifier] n ( output,per-stream)
- top=1/bottom=0/auto=-1 field first
- -dc precision
- Intra_dc_precision.
- -vtag fourcc/tag (output)
- Force video tag/fourcc. This is an alias for "-tag:v".
- -qphist (global)
- Show QP histogram
- -vbsf bitstream_filter
- Deprecated see -bsf
- -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 can take arguments of the following form:
- time[,time...]
- If the argument consists of timestamps, ffmpeg will round
the specified 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".
-force_key_frames 0:05:00,chapters-0.1
- expr:expr
- If the argument is prefixed with "expr:", the
string expr is interpreted like an expression and is evaluated for
each frame. A key frame is forced in case the evaluation is non-zero.
- 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
-force_key_frames expr:gte(t,n_forced*5)
-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.
- -copyinkf[:stream_specifier] (output,per-stream )
- When doing stream copy, copy also non-key frames found at the beginning.
- -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 default name of the form " type%d".
- cuda
- device is the number of the CUDA device.
- dxva2
- device is the number of the Direct3D 9 display adapter.
- vaapi
- device is either an X11 display name or a DRM render node. If not specified, it will attempt to open the default X11 display ( $DISPLAY) and then the first DRM render node ( /dev/dri/renderD128).
- 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
- opencl
- device selects the platform and device as
platform_index.device_index.
- platform_profile
- platform_version
- platform_name
- platform_vendor
- platform_extensions
- device_name
- device_vendor
- driver_version
- device_version
- device_profile
- device_extensions
- device_type
- -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_extensions=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.
- 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 enable.
- device_extensions
- A plus separated list of additional device extensions to enable.
- -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_surface+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 "hwupload" filter, or the device to map to with the
"hwmap" filter. Other filters may also make use of this
parameter when they require a hardware 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 input.
- -hwaccel[:stream_specifier] hwaccel (input,per-stream)
- Use hardware acceleration to decode the matching stream(s). The allowed values of hwaccel are:
- none
- Do not use any hardware acceleration (the default).
- auto
- Automatically select the hardware acceleration method.
- vdpau
- Use VDPAU (Video Decode and Presentation API for Unix) hardware acceleration.
- dxva2
- Use DXVA2 (DirectX Video Acceleration) hardware acceleration.
- vaapi
- Use VAAPI (Video Acceleration API) hardware acceleration.
- qsv
- Use the Intel QuickSync Video acceleration for video
transcoding.
- -hwaccel_device[:stream_specifier] hwaccel_device (input,per-stream)
- Select a device to use for hardware acceleration.
- -hwaccels
- List all hardware acceleration methods supported in this build of ffmpeg.
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 default 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 default to the number of input audio channels. For input streams this option 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 filtered or being automatically selected or mapped for any output.
See "-discard" option to disable streams individually.
- -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 supported sample formats.
- -af filtergraph (output)
- Create the filtergraph specified by filtergraph and
use it to filter the stream.
Advanced Audio options
- -atag fourcc/tag (output)
- Force audio tag/fourcc. This is an alias for "-tag:a".
- -absf bitstream_filter
- Deprecated, see -bsf
- -guess_layout_max channels (input,per-stream )
- If some input channel layout is not known, try to guess only if it corresponds 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.
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.
- -sbsf bitstream_filter
- Deprecated, see -bsf
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.
- -canvas_size size
- Set the size of the canvas used to render subtitles.
Advanced options
- -map [-]input_file_id[:stream_specifier ][?][,sync_file_id [:stream_specifier]] | [linklabel] (output)
- Designate one or more input streams as a source for the
output file. Each input stream is identified by the input file index
input_file_id and the input stream index input_stream_id
within the input file. Both indices start at 0. If specified,
sync_file_id: stream_specifier sets which input stream is
used as a presentation sync reference.
ffmpeg -i INPUT -map 0 output
ffmpeg -i INPUT -map 0:1 out.wav
ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov
ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT
ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT
ffmpeg -i INPUT -map 0:v -map 0:a? OUTPUT
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_channel [input_file_id.stream_specifier .channel_id |-1][?][:output_file_id.stream_specifier ]
- Map an audio channel from a given input to an output. If
output_file_id.stream_specifier is not set, the audio
channel will be mapped on all the audio streams.
ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT
ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT
ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1
ffmpeg -i stereo.wav -map 0:0 -map 0:0 -map_channel 0.0.0:0.0 -map_channel 0.0.1:0.1 -y out.ogg
ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv
ffmpeg -i INPUT -map_channel 0.0.0 -map_channel 0.0.1? OUTPUT
- -map_metadata[:metadata_spec_out] infile [:metadata_spec_in] (output,per-metadata )
- Set metadata information of the next output file from infile. Note that those are file indices (zero-based), not filenames. Optional metadata_spec_in/out parameters specify, which metadata to copy. A metadata 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 index.
- p:program_index
- per-program metadata. program_index is the zero-based program index.
ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3
ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv
- -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 negative 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 memory consumption is not supported on all systems, it will usually display 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.
- -re (input)
- Read input at native frame rate. Mainly used to simulate a grab device, or live input stream (e.g. when reading from a file). Should not be used with actual grab devices or live input streams (where it can cause packet loss). By default ffmpeg attempts to read the input(s) as fast as possible. This option will slow down the reading of the input(s) to the native frame rate of the input(s). It is useful for real-time output (e.g. live streaming).
- -vsync parameter
- Video sync method. For compatibility reasons old values can be specified as numbers. Newly added values will have to be specified as strings always.
- 0, passthrough
- Each frame is passed with its timestamp from the demuxer to the muxer.
- 1, cfr
- Frames will be duplicated and dropped to achieve exactly the requested constant frame rate.
- 2, vfr
- Frames are passed through with their timestamp or dropped so as to prevent 2 frames from having the same timestamp.
- drop
- As passthrough but destroys all timestamps, making the muxer generate fresh timestamps based on frame-rate.
- -1, auto
- Chooses between 1 and 2 depending on muxer capabilities. This is the default method.
- -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.
- -async samples_per_second
- Audio sync method. "Stretches/squeezes" the audio
stream to match the timestamps, the parameter is the maximum samples per
second by which the audio is changed. -async 1 is a special case where
only the start of the audio stream is corrected without any later
correction.
- -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.
- -start_at_zero
- When used with copyts, shift input timestamps so
they start at zero.
- -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.
- 0
- Use the decoder timebase.
- -1
- Try to make the choice automatically, in order to generate a sane output.
- -enc_time_base[:stream_specifier] timebase (output,per-stream)
- Set the encoder timebase. timebase is a floating point number, and can assume one of the following values:
- 0
- Assign a default value according to the media type.
- -1
- Use the input stream timebase when possible.
- >0
- Use the provided number as the timebase.
- -bitexact (input/output)
- Enable bitexact mode for (de)muxer and (de/en)coder
- -shortest (output)
- Finish encoding when the shortest input stream ends.
- -dts_delta_threshold
- Timestamp discontinuity delta threshold.
- -dts_error_threshold seconds
- Timestamp error delta threshold. This threshold use to discard crazy/damaged timestamps and the default is 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 reassigned to a different value.
ffmpeg -i inurl -streamid 0:33 -streamid 1:36 out.ts
- -bsf[:stream_specifier] bitstream_filters (output,per-stream)
- Set bitstream filters for matching streams.
bitstream_filters is a comma-separated list of bitstream filters.
Use the "-bsfs" option to get the list of bitstream filters.
ffmpeg -i h264.mp4 -c:v copy -bsf:v h264_mp4toannexb -an out.h264 ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt
- -tag[:stream_specifier] codec_tag (input/output,per-stream)
- Force a tag/fourcc for matching streams.
- -timecode hh:mm:ss SEPff
- 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 output of the same type -- see the -filter options.
filtergraph is a description of the filtergraph, as described in
the ``Filtergraph syntax'' section of the ffmpeg-filters manual.
ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map '[out]' out.mkv
ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map '[out]' out.mkv
ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv
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.
- -filter_complex_script filename (global )
- This option is similar to -filter_complex, the only difference is that its argument is the name of the file from which a complex filtergraph description is to be read.
- -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 argument 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)
- 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 manner; raising this value can avoid it.
- -sdp_file file (global)
- Print sdp information for an output stream to file. This allows dumping sdp information when at least one output isn't an rtp stream. (Requires 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 discarding of frames from a stream occurs at the demuxer and is not supported by all demuxers.
- none
- Discard 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 available:
- 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.
- -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.
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)
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 applied to the currently selected codec of the same type as the preset option. The argument passed to the "vpre", "apre", and "spre" preset options identifies 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 libvpx" and use "-vpre 1080p", then it will search for the file libvpx-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.avpreset in the same directories.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.mpgOr 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.mpgNote that you must activate the right video source and channel before launching ffmpeg with any TV viewer such as < http://linux.bytesex.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 viaffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0 /tmp/out.mpg0.0 is display.screen number of your X11 server, same as the DISPLAY environment variable.
ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0+10,20 /tmp/out.mpg0.0 is display.screen number of your X11 server, same as the DISPLAY environment 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
/tmp/test0.Y, /tmp/test0.U, /tmp/test0.V, /tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
- •
- You can input from a raw YUV420P file:
ffmpeg -i /tmp/test.yuv /tmp/out.avi
- •
- 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
- •
- You can also do audio and video conversions at the same
time:
ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
- •
- 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
- •
- 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
- •
- You can extract images from a video, or create a video from
many images:
ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
ffmpeg -f image2 -framerate 12 -i foo-%03d.jpeg -s WxH foo.avi
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
- •
- 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