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 SI unit prefixes, for example 'K', 'M', 'G'.
4 If 'i' is appended after the prefix, binary prefixes are used,
5 which are based on powers of 1024 instead of powers of 1000.
6 The 'B' postfix multiplies the value by 8, and can be
7 appended after a unit prefix or used alone. This allows using for
8 example 'KB', 'MiB', 'G' and 'B' as number postfix.
10 Options which do not take arguments are boolean options, and set the
11 corresponding value to true. They can be set to false by prefixing
12 with "no" the option name, for example using "-nofoo" in the
13 command line will set to false the boolean option with name "foo".
15 @anchor{Stream specifiers}
16 @section Stream specifiers
17 Some options are applied per-stream, e.g. bitrate or codec. Stream specifiers
18 are used to precisely specify which stream(s) does a given option belong to.
20 A stream specifier is a string generally appended to the option name and
21 separated from it by a colon. E.g. @code{-codec:a:1 ac3} option contains
22 @code{a:1} stream specifier, which matches the second audio stream. Therefore it
23 would select the ac3 codec for the second audio stream.
25 A stream specifier can match several streams, the option is then applied to all
26 of them. E.g. the stream specifier in @code{-b:a 128k} matches all audio
29 An empty stream specifier matches all streams, for example @code{-codec copy}
30 or @code{-codec: copy} would copy all the streams without reencoding.
32 Possible forms of stream specifiers are:
34 @item @var{stream_index}
35 Matches the stream with this index. E.g. @code{-threads:1 4} would set the
36 thread count for the second stream to 4.
37 @item @var{stream_type}[:@var{stream_index}]
38 @var{stream_type} is one of: 'v' for video, 'a' for audio, 's' for subtitle,
39 'd' for data and 't' for attachments. If @var{stream_index} is given, then
40 matches stream number @var{stream_index} of this type. Otherwise matches all
42 @item p:@var{program_id}[:@var{stream_index}]
43 If @var{stream_index} is given, then matches stream number @var{stream_index} in
44 program with id @var{program_id}. Otherwise matches all streams in this program.
45 @item #@var{stream_id}
46 Matches the stream by format-specific ID.
49 @section Generic options
51 These options are shared amongst the av* tools.
58 @item -h, -?, -help, --help [@var{arg}]
59 Show help. An optional parameter may be specified to print help about a specific
62 Possible values of @var{arg} are:
64 @item decoder=@var{decoder_name}
65 Print detailed information about the decoder named @var{decoder_name}. Use the
66 @option{-decoders} option to get a list of all decoders.
68 @item encoder=@var{encoder_name}
69 Print detailed information about the encoder named @var{encoder_name}. Use the
70 @option{-encoders} option to get a list of all encoders.
72 @item demuxer=@var{demuxer_name}
73 Print detailed information about the demuxer named @var{demuxer_name}. Use the
74 @option{-formats} option to get a list of all demuxers and muxers.
76 @item muxer=@var{muxer_name}
77 Print detailed information about the muxer named @var{muxer_name}. Use the
78 @option{-formats} option to get a list of all muxers and demuxers.
86 Show available formats.
88 The fields preceding the format names have the following meanings:
97 Show all codecs known to libavcodec.
99 Note that the term 'codec' is used throughout this documentation as a shortcut
100 for what is more correctly called a media bitstream format.
103 Show available decoders.
106 Show all available encoders.
109 Show available bitstream filters.
112 Show available protocols.
115 Show available libavfilter filters.
118 Show available pixel formats.
121 Show available sample formats.
124 Show channel names and standard channel layouts.
126 @item -loglevel @var{loglevel} | -v @var{loglevel}
127 Set the logging level used by the library.
128 @var{loglevel} is a number or a string containing one of the following values:
140 By default the program logs to stderr, if coloring is supported by the
141 terminal, colors are used to mark errors and warnings. Log coloring
142 can be disabled setting the environment variable
143 @env{AV_LOG_FORCE_NOCOLOR} or @env{NO_COLOR}, or can be forced setting
144 the environment variable @env{AV_LOG_FORCE_COLOR}.
145 The use of the environment variable @env{NO_COLOR} is deprecated and
146 will be dropped in a following FFmpeg version.
149 Dump full command line and console output to a file named
150 @code{@var{program}-@var{YYYYMMDD}-@var{HHMMSS}.log} in the current
152 This file can be useful for bug reports.
153 It also implies @code{-loglevel verbose}.
155 Setting the environment variable @code{FFREPORT} to any value has the same
156 effect. If the value is a ':'-separated key=value sequence, these options
157 will affect the report; options values must be
158 @ref{quoting_and_escaping, escaped} if they contain special characters or
159 the options delimiter ':'. The following option is recognized:
162 set the file name to use for the report; @code{%p} is expanded to the name
163 of the program, @code{%t} is expanded to a timestamp, @code{%%} is expanded
167 Errors in parsing the environment variable are not fatal, and will not
168 appear in the report.
170 @item -cpuflags flags (@emph{global})
171 Allows setting and clearing cpu flags. This option is intended
172 for testing. Do not use it unless you know what you're doing.
174 ffmpeg -cpuflags -sse+mmx ...
175 ffmpeg -cpuflags mmx ...
176 ffmpeg -cpuflags 0 ...
183 These options are provided directly by the libavformat, libavdevice and
184 libavcodec libraries. To see the list of available AVOptions, use the
185 @option{-help} option. They are separated into two categories:
188 These options can be set for any container, codec or device. Generic options
189 are listed under AVFormatContext options for containers/devices and under
190 AVCodecContext options for codecs.
192 These options are specific to the given container, device or codec. Private
193 options are listed under their corresponding containers/devices/codecs.
196 For example to write an ID3v2.3 header instead of a default ID3v2.4 to
197 an MP3 file, use the @option{id3v2_version} private option of the MP3
200 ffmpeg -i input.flac -id3v2_version 3 out.mp3
203 All codec AVOptions are obviously per-stream, so the chapter on stream
204 specifiers applies to them
206 Note @option{-nooption} syntax cannot be used for boolean AVOptions,
207 use @option{-option 0}/@option{-option 1}.
209 Note2 old undocumented way of specifying per-stream AVOptions by prepending
210 v/a/s to the options name is now obsolete and will be removed soon.
212 @include avoptions_codec.texi
213 @include avoptions_format.texi