All the numerical options, if not specified otherwise, accept in input a string representing a number, which may contain one of the International System number postfixes, for example 'K', 'M', 'G'. If 'i' is appended after the postfix, powers of 2 are used instead of powers of 10. The 'B' postfix multiplies the value for 8, and can be appended after another postfix or used alone. This allows using for example 'KB', 'MiB', 'G' and 'B' as postfix.

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

Stream specifiers
=================

Some options are applied per-stream, e.g. bitrate or codec. Stream specifiers are used to precisely specify which stream(s) does a given option belong 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 option contains 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, the option is then 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.

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

p:PROGRAM_ID[:STREAM_INDEX]
     If STREAM_INDEX is given, then matches stream number STREAM_INDEX in program with id PROGRAM_ID. Otherwise matches all streams in this program.

#STREAM_ID
     Matches the stream by format-specific ID.

Generic options
===============

These options are shared amongst the av* tools.

-L
     Show license.

-h, -?, -help, --help [ARG]
     Show help. An optional parameter may be specified to print help about a specific item.

     Possible values of ARG are:

     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.

-version
     Show version.

-formats
     Show available formats.

     The fields preceding the format names have the following meanings:

     D
          Decoding available

     E
          Encoding available

-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.

-loglevel LOGLEVEL | -v LOGLEVEL
     Set the logging level used by the library. LOGLEVEL is a number or a string containing one of the following values:

     quiet

     panic

     fatal

     error

     warning

     info

     verbose

     debug

     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 NO_COLOR, or can be forced setting the environment variable AV_LOG_FORCE_COLOR. The use of the environment variable NO_COLOR is deprecated and will be dropped in a following FFmpeg version.

-report
     Dump full command line and console 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 verbose.

     Note: setting the environment variable FFREPORT to any value has the same effect.

-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 ...

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.

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 obviously per-stream, so the chapter on stream specifiers applies to them

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

Note2 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.

     [file avoptions_codec.texi not included]
     [file avoptions_format.texi not included]