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. 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. @example ffmpeg -i INPUT -/filter:v filter.script OUTPUT @end example will load a filtergraph description from the file named @file{filter.script}. @anchor{Stream specifiers} @section 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. @code{-codec:a:1 ac3} contains the @code{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 @code{-b:a 128k} matches all audio streams. An empty stream specifier matches all streams. For example, @code{-codec copy} or @code{-codec: copy} would copy all the streams without reencoding. Possible forms of stream specifiers are: @table @option @item @var{stream_index} Matches the stream with this index. E.g. @code{-threads:1 4} would set the thread count for the second stream to 4. If @var{stream_index} is used as an additional stream specifier (see below), then it selects stream number @var{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. @item @var{stream_type}[:@var{additional_stream_specifier}] @var{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 @var{additional_stream_specifier} is used, then it matches streams which both have this type and match the @var{additional_stream_specifier}. Otherwise, it matches all streams of the specified type. @item g:@var{group_specifier}[:@var{additional_stream_specifier}] Matches streams which are in the group with the specifier @var{group_specifier}. if @var{additional_stream_specifier} is used, then it matches streams which both are part of the group and match the @var{additional_stream_specifier}. @var{group_specifier} may be one of the following: @table @option @item @var{group_index} Match the stream with this group index. @item #@var{group_id} or i:@var{group_id} Match the stream with this group id. @end table @item p:@var{program_id}[:@var{additional_stream_specifier}] Matches streams which are in the program with the id @var{program_id}. If @var{additional_stream_specifier} is used, then it matches streams which both are part of the program and match the @var{additional_stream_specifier}. @item #@var{stream_id} or i:@var{stream_id} Match the stream by stream id (e.g. PID in MPEG-TS container). @item m:@var{key}[:@var{value}] Matches streams with the metadata tag @var{key} having the specified value. If @var{value} is not given, matches streams that contain the given tag with any value. @item 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 @command{ffmpeg}, matching by metadata will only work properly for input files. @end table @section Generic options These options are shared amongst the ff* tools. @table @option @item -L Show license. @item -h, -?, -help, --help [@var{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 @var{arg} are: @table @option @item long Print advanced tool options in addition to the basic tool options. @item full Print complete list of options, including shared and private options for encoders, decoders, demuxers, muxers, filters, etc. @item decoder=@var{decoder_name} Print detailed information about the decoder named @var{decoder_name}. Use the @option{-decoders} option to get a list of all decoders. @item encoder=@var{encoder_name} Print detailed information about the encoder named @var{encoder_name}. Use the @option{-encoders} option to get a list of all encoders. @item demuxer=@var{demuxer_name} Print detailed information about the demuxer named @var{demuxer_name}. Use the @option{-formats} option to get a list of all demuxers and muxers. @item muxer=@var{muxer_name} Print detailed information about the muxer named @var{muxer_name}. Use the @option{-formats} option to get a list of all muxers and demuxers. @item filter=@var{filter_name} Print detailed information about the filter named @var{filter_name}. Use the @option{-filters} option to get a list of all filters. @item bsf=@var{bitstream_filter_name} Print detailed information about the bitstream filter named @var{bitstream_filter_name}. Use the @option{-bsfs} option to get a list of all bitstream filters. @item protocol=@var{protocol_name} Print detailed information about the protocol named @var{protocol_name}. Use the @option{-protocols} option to get a list of all protocols. @end table @item -version Show version. @item -buildconf Show the build configuration, one option per line. @item -formats Show available formats (including devices). @item -demuxers Show available demuxers. @item -muxers Show available muxers. @item -devices Show available devices. @item -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. @item -decoders Show available decoders. @item -encoders Show all available encoders. @item -bsfs Show available bitstream filters. @item -protocols Show available protocols. @item -filters Show available libavfilter filters. @item -pix_fmts Show available pixel formats. @item -sample_fmts Show available sample formats. @item -layouts Show channel names and standard channel layouts. @item -dispositions Show stream dispositions. @item -colors Show recognized color names. @item -sources @var{device}[,@var{opt1}=@var{val1}[,@var{opt2}=@var{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. @example ffmpeg -sources pulse,server=192.168.0.4 @end example @item -sinks @var{device}[,@var{opt1}=@var{val1}[,@var{opt2}=@var{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. @example ffmpeg -sinks pulse,server=192.168.0.4 @end example @item -loglevel [@var{flags}+]@var{loglevel} | -v [@var{flags}+]@var{loglevel} Set logging level and flags used by the library. The optional @var{flags} prefix can consist of the following values: @table @samp @item 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. @item level Indicates that log output should add a @code{[level]} prefix to each message line. This can be used as an alternative to log coloring, e.g. when dumping the log to file. @end table Flags can also be used alone by adding a '+'/'-' prefix to set/reset a single flag without affecting other @var{flags} or changing @var{loglevel}. When setting both @var{flags} and @var{loglevel}, a '+' separator is expected between the last @var{flags} value and before @var{loglevel}. @var{loglevel} is a string or a number containing one of the following values: @table @samp @item quiet, -8 Show nothing at all; be silent. @item 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. @item fatal, 8 Only show fatal errors. These are errors after which the process absolutely cannot continue. @item error, 16 Show all errors, including ones which can be recovered from. @item warning, 24 Show all warnings and errors. Any message related to possibly incorrect or unexpected events will be shown. @item info, 32 Show informative messages during processing. This is in addition to warnings and errors. This is the default value. @item verbose, 40 Same as @code{info}, except more verbose. @item debug, 48 Show everything, including debugging information. @item trace, 56 @end table For example to enable repeated log output, add the @code{level} prefix, and set @var{loglevel} to @code{verbose}: @example ffmpeg -loglevel repeat+level+verbose -i input output @end example Another example that enables repeated log output without affecting current state of @code{level} prefix flag or @var{loglevel}: @example ffmpeg [...] -loglevel +repeat @end example 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 @env{AV_LOG_FORCE_NOCOLOR}, or can be forced setting the environment variable @env{AV_LOG_FORCE_COLOR}. @item -report Dump full command line and log output to a file named @code{@var{program}-@var{YYYYMMDD}-@var{HHMMSS}.log} in the current directory. This file can be useful for bug reports. It also implies @code{-loglevel debug}. Setting the environment variable @env{FFREPORT} to any value has the same effect. 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: @table @option @item file set the file name to use for the report; @code{%p} is expanded to the name of the program, @code{%t} is expanded to a timestamp, @code{%%} is expanded to a plain @code{%} @item level set the log verbosity level using a numerical value (see @code{-loglevel}). @end table For example, to output a report to a file named @file{ffreport.log} using a log level of @code{32} (alias for log level @code{info}): @example FFREPORT=file=ffreport.log:level=32 ffmpeg -i input output @end example Errors in parsing the environment variable are not fatal, and will not appear in the report. @item -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. @item -cpuflags flags (@emph{global}) Allows setting and clearing cpu flags. This option is intended for testing. Do not use it unless you know what you're doing. @example ffmpeg -cpuflags -sse+mmx ... ffmpeg -cpuflags mmx ... ffmpeg -cpuflags 0 ... @end example Possible flags for this option are: @table @samp @item x86 @table @samp @item mmx @item mmxext @item sse @item sse2 @item sse2slow @item sse3 @item sse3slow @item ssse3 @item atom @item sse4.1 @item sse4.2 @item avx @item avx2 @item xop @item fma3 @item fma4 @item 3dnow @item 3dnowext @item bmi1 @item bmi2 @item cmov @end table @item ARM @table @samp @item armv5te @item armv6 @item armv6t2 @item vfp @item vfpv3 @item neon @item setend @end table @item AArch64 @table @samp @item armv8 @item vfp @item neon @end table @item PowerPC @table @samp @item altivec @end table @item Specific Processors @table @samp @item pentium2 @item pentium3 @item pentium4 @item k6 @item k62 @item athlon @item athlonxp @item k8 @end table @end table @item -cpucount @var{count} (@emph{global}) Override detection of CPU count. This option is intended for testing. Do not use it unless you know what you're doing. @example ffmpeg -cpucount 2 @end example @item -max_alloc @var{bytes} Set the maximum size limit for allocating a block on the heap by ffmpeg's family of malloc functions. Exercise @strong{extreme caution} when using this option. Don't use if you do not understand the full consequence of doing so. Default is INT_MAX. @end table @section AVOptions These options are provided directly by the libavformat, libavdevice and libavcodec libraries. To see the list of available AVOptions, use the @option{-help} option. They are separated into two categories: @table @option @item 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. @item private These options are specific to the given container, device or codec. Private options are listed under their corresponding containers/devices/codecs. @end table For example to write an ID3v2.3 header instead of a default ID3v2.4 to an MP3 file, use the @option{id3v2_version} private option of the MP3 muxer: @example ffmpeg -i input.flac -id3v2_version 3 out.mp3 @end example All codec AVOptions are per-stream, and thus a stream specifier should be attached to them: @example 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 @end example In 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 @option{-nooption} syntax cannot be used for boolean AVOptions, use @option{-option 0}/@option{-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.