1 All the numerical options, if not specified otherwise, accept in input
2 a string representing a number, which may contain one of the
3 International System number postfixes, for example 'K', 'M', 'G'.
4 If 'i' is appended after the postfix, powers of 2 are used instead of
5 powers of 10. The 'B' postfix multiplies the value for 8, and can be
6 appended after another postfix or used alone. This allows using for
7 example 'KB', 'MiB', 'G' and 'B' as postfix.
9 Options which do not take arguments are boolean options, and set the
10 corresponding value to true. They can be set to false by prefixing
11 with "no" the option name, for example using "-nofoo" in the
12 command line will set to false the boolean option with name "foo".
14 @anchor{Stream specifiers}
15 @section Stream specifiers
16 Some options are applied per-stream, e.g. bitrate or codec. Stream specifiers
17 are used to precisely specify which stream(s) does a given option belong to.
19 A stream specifier is a string generally appended to the option name and
20 separated from it by a colon. E.g. @code{-codec:a:1 ac3} option contains
21 @code{a:1} stream specifier, which matches the second audio stream. Therefore it
22 would select the ac3 codec for the second audio stream.
24 A stream specifier can match several streams, the option is then applied to all
25 of them. E.g. the stream specifier in @code{-b:a 128k} matches all audio
28 An empty stream specifier matches all streams, for example @code{-codec copy}
29 or @code{-codec: copy} would copy all the streams without reencoding.
31 Possible forms of stream specifiers are:
33 @item @var{stream_index}
34 Matches the stream with this index. E.g. @code{-threads:1 4} would set the
35 thread count for the second stream to 4.
36 @item @var{stream_type}[:@var{stream_index}]
37 @var{stream_type} is one of: 'v' for video, 'a' for audio, 's' for subtitle,
38 'd' for data and 't' for attachments. If @var{stream_index} is given, then
39 matches stream number @var{stream_index} of this type. Otherwise matches all
41 @item p:@var{program_id}[:@var{stream_index}]
42 If @var{stream_index} is given, then matches stream number @var{stream_index} in
43 program with id @var{program_id}. Otherwise matches all streams in this program.
44 @item #@var{stream_id}
45 Matches the stream by format-specific ID.
48 @section Generic options
50 These options are shared amongst the av* tools.
57 @item -h, -?, -help, --help [@var{arg}]
58 Show help. An optional parameter may be specified to print help about a specific
61 Possible values of @var{arg} are:
63 @item decoder=@var{decoder_name}
64 Print detailed information about the decoder named @var{decoder_name}. Use the
65 @option{-decoders} option to get a list of all decoders.
67 @item encoder=@var{encoder_name}
68 Print detailed information about the encoder named @var{encoder_name}. Use the
69 @option{-encoders} option to get a list of all encoders.
71 @item demuxer=@var{demuxer_name}
72 Print detailed information about the demuxer named @var{demuxer_name}. Use the
73 @option{-formats} option to get a list of all demuxers and muxers.
75 @item muxer=@var{muxer_name}
76 Print detailed information about the muxer named @var{muxer_name}. Use the
77 @option{-formats} option to get a list of all muxers and demuxers.
85 Show available formats.
87 The fields preceding the format names have the following meanings:
96 Show all codecs known to libavcodec.
98 Note that the term 'codec' is used throughout this documentation as a shortcut
99 for what is more correctly called a media bitstream format.
102 Show available decoders.
105 Show all available encoders.
108 Show available bitstream filters.
111 Show available protocols.
114 Show available libavfilter filters.
117 Show available pixel formats.
120 Show available sample formats.
122 @item -loglevel @var{loglevel} | -v @var{loglevel}
123 Set the logging level used by the library.
124 @var{loglevel} is a number or a string containing one of the following values:
136 By default the program logs to stderr, if coloring is supported by the
137 terminal, colors are used to mark errors and warnings. Log coloring
138 can be disabled setting the environment variable
139 @env{AV_LOG_FORCE_NOCOLOR} or @env{NO_COLOR}, or can be forced setting
140 the environment variable @env{AV_LOG_FORCE_COLOR}.
141 The use of the environment variable @env{NO_COLOR} is deprecated and
142 will be dropped in a following FFmpeg version.
145 Dump full command line and console output to a file named
146 @code{@var{program}-@var{YYYYMMDD}-@var{HHMMSS}.log} in the current
148 This file can be useful for bug reports.
149 It also implies @code{-loglevel verbose}.
151 Note: setting the environment variable @code{FFREPORT} to any value has the
154 @item -cpuflags flags (@emph{global})
155 Allows setting and clearing cpu flags. This option is intended
156 for testing. Do not use it unless you know what you're doing.
158 ffmpeg -cpuflags -sse+mmx ...
159 ffmpeg -cpuflags mmx ...
160 ffmpeg -cpuflags 0 ...
167 These options are provided directly by the libavformat, libavdevice and
168 libavcodec libraries. To see the list of available AVOptions, use the
169 @option{-help} option. They are separated into two categories:
172 These options can be set for any container, codec or device. Generic options
173 are listed under AVFormatContext options for containers/devices and under
174 AVCodecContext options for codecs.
176 These options are specific to the given container, device or codec. Private
177 options are listed under their corresponding containers/devices/codecs.
180 For example to write an ID3v2.3 header instead of a default ID3v2.4 to
181 an MP3 file, use the @option{id3v2_version} private option of the MP3
184 ffmpeg -i input.flac -id3v2_version 3 out.mp3
187 All codec AVOptions are obviously per-stream, so the chapter on stream
188 specifiers applies to them
190 Note @option{-nooption} syntax cannot be used for boolean AVOptions,
191 use @option{-option 0}/@option{-option 1}.
193 Note2 old undocumented way of specifying per-stream AVOptions by prepending
194 v/a/s to the options name is now obsolete and will be removed soon.
196 @include avoptions_codec.texi
197 @include avoptions_format.texi