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diff --git a/ffmpeg/doc/ffmpeg.texi b/ffmpeg/doc/ffmpeg.texi deleted file mode 100644 index 0a930ce..0000000 --- a/ffmpeg/doc/ffmpeg.texi +++ /dev/null @@ -1,1497 +0,0 @@ -\input texinfo @c -*- texinfo -*- - -@settitle ffmpeg Documentation -@titlepage -@center @titlefont{ffmpeg Documentation} -@end titlepage - -@top - -@contents - -@chapter Synopsis - -ffmpeg [@var{global_options}] @{[@var{input_file_options}] -i @file{input_file}@} ... @{[@var{output_file_options}] @file{output_file}@} ... - -@chapter Description -@c man begin DESCRIPTION - -@command{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. - -@command{ffmpeg} reads from an arbitrary number of input "files" (which can be regular -files, pipes, network streams, grabbing devices, etc.), specified by the -@code{-i} option, and writes to an arbitrary number of output "files", which are -specified by a plain output filename. Anything found on the command line which -cannot be interpreted as an option is considered to be an output filename. - -Each input or output file 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 @code{-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 @code{0}, the second is @code{1}, etc. Similarly, streams -within a file are referred to by their indices. E.g. @code{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. - -@itemize -@item -To set the video bitrate of the output file to 64 kbit/s: -@example -ffmpeg -i input.avi -b:v 64k -bufsize 64k output.avi -@end example - -@item -To force the frame rate of the output file to 24 fps: -@example -ffmpeg -i input.avi -r 24 output.avi -@end example - -@item -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: -@example -ffmpeg -r 1 -i input.m2v -r 24 output.avi -@end example -@end itemize - -The format option may be needed for raw input files. - -@c man end DESCRIPTION - -@chapter Detailed description -@c man begin DETAILED DESCRIPTION - -The transcoding process in @command{ffmpeg} for each output can be described by -the following diagram: - -@example - _______ ______________ _________ ______________ ________ -| | | | | | | | | | -| input | demuxer | encoded data | decoder | decoded | encoder | encoded data | muxer | output | -| file | ---------> | packets | ---------> | frames | ---------> | packets | -------> | file | -|_______| |______________| |_________| |______________| |________| - -@end example - -@command{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, @command{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. - -@section Filtering -Before encoding, @command{ffmpeg} can process raw audio and video frames using -filters from the libavfilter library. Several chained filters form a filter -graph. @command{ffmpeg} distinguishes between two types of filtergraphs: -simple and complex. - -@subsection 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: - -@example - _________ __________ ______________ -| | | | | | -| decoded | simple filtergraph | filtered | encoder | encoded data | -| frames | -------------------> | frames | ---------> | packets | -|_________| |__________| |______________| - -@end example - -Simple filtergraphs are configured with the per-stream @option{-filter} option -(with @option{-vf} and @option{-af} aliases for video and audio respectively). -A simple filtergraph for video can look for example like this: - -@example - _______ _____________ _______ _____ ________ -| | | | | | | | | | -| input | ---> | deinterlace | ---> | scale | ---> | fps | ---> | output | -|_______| |_____________| |_______| |_____| |________| - -@end example - -Note that some filters change frame properties but not frame contents. E.g. the -@code{fps} filter in the example above changes number of frames, but does not -touch the frame contents. Another example is the @code{setpts} filter, which -only sets timestamps and otherwise passes the frames unchanged. - -@subsection 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: - -@example - _________ -| | -| input 0 |\ __________ -|_________| \ | | - \ _________ /| output 0 | - \ | | / |__________| - _________ \| complex | / -| | | |/ -| input 1 |---->| filter |\ -|_________| | | \ __________ - /| graph | \ | | - / | | \| output 1 | - _________ / |_________| |__________| -| | / -| input 2 |/ -|_________| - -@end example - -Complex filtergraphs are configured with the @option{-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 @option{-lavfi} option is equivalent to @option{-filter_complex}. - -A trivial example of a complex filtergraph is the @code{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 @code{amix} filter. - -@section Stream copy -Stream copy is a mode selected by supplying the @code{copy} parameter to the -@option{-codec} option. It makes @command{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: - -@example - _______ ______________ ________ -| | | | | | -| input | demuxer | encoded data | muxer | output | -| file | ---------> | packets | -------> | file | -|_______| |______________| |________| - -@end example - -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. - -@c man end DETAILED DESCRIPTION - -@chapter Stream selection -@c man begin STREAM SELECTION - -By default, @command{ffmpeg} includes only one stream of each type (video, audio, subtitle) -present in the input files and adds them to each output file. It picks the -"best" of each 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. In the case where several streams of -the same type rate equally, the stream with the lowest index is chosen. - -You can disable some of those defaults by using the @code{-vn/-an/-sn} options. For -full manual control, use the @code{-map} option, which disables the defaults just -described. - -@c man end STREAM SELECTION - -@chapter Options -@c man begin OPTIONS - -@include fftools-common-opts.texi - -@section Main options - -@table @option - -@item -f @var{fmt} (@emph{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. - -@item -i @var{filename} (@emph{input}) -input file name - -@item -y (@emph{global}) -Overwrite output files without asking. - -@item -n (@emph{global}) -Do not overwrite output files, and exit immediately if a specified -output file already exists. - -@item -c[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream}) -@itemx -codec[:@var{stream_specifier}] @var{codec} (@emph{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. @var{codec} is the name of a -decoder/encoder or a special value @code{copy} (output only) to indicate that -the stream is not to be re-encoded. - -For example -@example -ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT -@end example -encodes all video streams with libx264 and copies all audio streams. - -For each stream, the last matching @code{c} option is applied, so -@example -ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT -@end example -will copy all the streams except the second video, which will be encoded with -libx264, and the 138th audio, which will be encoded with libvorbis. - -@item -t @var{duration} (@emph{output}) -Stop writing the output after its duration reaches @var{duration}. -@var{duration} may be a number in seconds, or in @code{hh:mm:ss[.xxx]} form. - --to and -t are mutually exclusive and -t has priority. - -@item -to @var{position} (@emph{output}) -Stop writing the output at @var{position}. -@var{position} may be a number in seconds, or in @code{hh:mm:ss[.xxx]} form. - --to and -t are mutually exclusive and -t has priority. - -@item -fs @var{limit_size} (@emph{output}) -Set the file size limit, expressed in bytes. - -@item -ss @var{position} (@emph{input/output}) -When used as an input option (before @code{-i}), seeks in this input file to -@var{position}. Note the in most formats it is not possible to seek exactly, so -@command{ffmpeg} will seek to the closest seek point before @var{position}. -When transcoding and @option{-accurate_seek} is enabled (the default), this -extra segment between the seek point and @var{position} will be decoded and -discarded. When doing stream copy or when @option{-noaccurate_seek} is used, it -will be preserved. - -When used as an output option (before an output filename), decodes but discards -input until the timestamps reach @var{position}. - -@var{position} may be either in seconds or in @code{hh:mm:ss[.xxx]} form. - -@item -itsoffset @var{offset} (@emph{input}) -Set the input time offset in seconds. -@code{[-]hh:mm:ss[.xxx]} syntax is also supported. -The offset is added to the timestamps of the input files. -Specifying a positive offset means that the corresponding -streams are delayed by @var{offset} seconds. - -@item -timestamp @var{time} (@emph{output}) -Set the recording timestamp in the container. -The syntax for @var{time} is: -@example -now|([(YYYY-MM-DD|YYYYMMDD)[T|t| ]]((HH:MM:SS[.m...])|(HHMMSS[.m...]))[Z|z]) -@end example -If the value is "now" it takes the current time. -Time is local time unless 'Z' or 'z' is appended, in which case it is -interpreted as UTC. -If the year-month-day part is not specified it takes the current -year-month-day. - -@item -metadata[:metadata_specifier] @var{key}=@var{value} (@emph{output,per-metadata}) -Set a metadata key/value pair. - -An optional @var{metadata_specifier} may be given to set metadata -on streams or chapters. See @code{-map_metadata} documentation for -details. - -This option overrides metadata set with @code{-map_metadata}. It is -also possible to delete metadata by using an empty value. - -For example, for setting the title in the output file: -@example -ffmpeg -i in.avi -metadata title="my title" out.flv -@end example - -To set the language of the first audio stream: -@example -ffmpeg -i INPUT -metadata:s:a:1 language=eng OUTPUT -@end example - -@item -target @var{type} (@emph{output}) -Specify target file type (@code{vcd}, @code{svcd}, @code{dvd}, @code{dv}, -@code{dv50}). @var{type} may be prefixed with @code{pal-}, @code{ntsc-} or -@code{film-} to use the corresponding standard. All the format options -(bitrate, codecs, buffer sizes) are then set automatically. You can just type: - -@example -ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg -@end example - -Nevertheless you can specify additional options as long as you know -they do not conflict with the standard, as in: - -@example -ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg -@end example - -@item -dframes @var{number} (@emph{output}) -Set the number of data frames to record. This is an alias for @code{-frames:d}. - -@item -frames[:@var{stream_specifier}] @var{framecount} (@emph{output,per-stream}) -Stop writing to the stream after @var{framecount} frames. - -@item -q[:@var{stream_specifier}] @var{q} (@emph{output,per-stream}) -@itemx -qscale[:@var{stream_specifier}] @var{q} (@emph{output,per-stream}) -Use fixed quality scale (VBR). The meaning of @var{q}/@var{qscale} is -codec-dependent. -If @var{qscale} is used without a @var{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. - -@anchor{filter_option} -@item -filter[:@var{stream_specifier}] @var{filtergraph} (@emph{output,per-stream}) -Create the filtergraph specified by @var{filtergraph} and use it to -filter the stream. - -@var{filtergraph} is a description of the filtergraph to apply to -the stream, and must have a single input and a single output of the -same type of the stream. In the filtergraph, the input is associated -to the label @code{in}, and the output to the label @code{out}. See -the ffmpeg-filters manual for more information about the filtergraph -syntax. - -See the @ref{filter_complex_option,,-filter_complex option} if you -want to create filtergraphs with multiple inputs and/or outputs. - -@item -filter_script[:@var{stream_specifier}] @var{filename} (@emph{output,per-stream}) -This option is similar to @option{-filter}, the only difference is that its -argument is the name of the file from which a filtergraph description is to be -read. - -@item -pre[:@var{stream_specifier}] @var{preset_name} (@emph{output,per-stream}) -Specify the preset for matching stream(s). - -@item -stats (@emph{global}) -Print encoding progress/statistics. It is on by default, to explicitly -disable it you need to specify @code{-nostats}. - -@item -progress @var{url} (@emph{global}) -Send program-friendly progress information to @var{url}. - -Progress information is written approximately every second and at the end of -the encoding process. It is made of "@var{key}=@var{value}" lines. @var{key} -consists of only alphanumeric characters. The last key of a sequence of -progress information is always "progress". - -@item -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 -@code{-nostdin}. - -Disabling interaction on standard input is useful, for example, if -ffmpeg is in the background process group. Roughly the same result can -be achieved with @code{ffmpeg ... < /dev/null} but it requires a -shell. - -@item -debug_ts (@emph{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. - -See also the option @code{-fdebug ts}. - -@item -attach @var{filename} (@emph{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 @code{-map} or automatic mappings). - -Note that for Matroska you also have to set the mimetype metadata tag: -@example -ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv -@end example -(assuming that the attachment stream will be third in the output file). - -@item -dump_attachment[:@var{stream_specifier}] @var{filename} (@emph{input,per-stream}) -Extract the matching attachment stream into a file named @var{filename}. If -@var{filename} is empty, then the value of the @code{filename} metadata tag -will be used. - -E.g. to extract the first attachment to a file named 'out.ttf': -@example -ffmpeg -dump_attachment:t:0 out.ttf -i INPUT -@end example -To extract all attachments to files determined by the @code{filename} tag: -@example -ffmpeg -dump_attachment:t "" -i INPUT -@end example - -Technical note -- attachments are implemented as codec extradata, so this -option can actually be used to extract extradata from any stream, not just -attachments. - -@end table - -@section Video Options - -@table @option -@item -vframes @var{number} (@emph{output}) -Set the number of video frames to record. This is an alias for @code{-frames:v}. -@item -r[:@var{stream_specifier}] @var{fps} (@emph{input/output,per-stream}) -Set frame rate (Hz value, fraction or abbreviation). - -As an input option, ignore any timestamps stored in the file and instead -generate timestamps assuming constant frame rate @var{fps}. - -As an output option, duplicate or drop input frames to achieve constant output -frame rate @var{fps}. - -@item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream}) -Set frame size. - -As an input option, this is a shortcut for the @option{video_size} private -option, recognized by some demuxers for which the frame size is either not -stored in the file or is configurable -- e.g. raw video or video grabbers. - -As an output option, this inserts the @code{scale} video filter to the -@emph{end} of the corresponding filtergraph. Please use the @code{scale} filter -directly to insert it at the beginning or some other place. - -The format is @samp{wxh} (default - same as source). - -@item -aspect[:@var{stream_specifier}] @var{aspect} (@emph{output,per-stream}) -Set the video display aspect ratio specified by @var{aspect}. - -@var{aspect} can be a floating point number string, or a string of the -form @var{num}:@var{den}, where @var{num} and @var{den} are the -numerator and denominator of the aspect ratio. For example "4:3", -"16:9", "1.3333", and "1.7777" are valid argument values. - -If used together with @option{-vcodec copy}, it will affect the aspect ratio -stored at container level, but not the aspect ratio stored in encoded -frames, if it exists. - -@item -vn (@emph{output}) -Disable video recording. - -@item -vcodec @var{codec} (@emph{output}) -Set the video codec. This is an alias for @code{-codec:v}. - -@item -pass[:@var{stream_specifier}] @var{n} (@emph{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: -@example -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 -@end example - -@item -passlogfile[:@var{stream_specifier}] @var{prefix} (@emph{output,per-stream}) -Set two-pass log file name prefix to @var{prefix}, the default file name -prefix is ``ffmpeg2pass''. The complete file name will be -@file{PREFIX-N.log}, where N is a number specific to the output -stream - -@item -vlang @var{code} -Set the ISO 639 language code (3 letters) of the current video stream. - -@item -vf @var{filtergraph} (@emph{output}) -Create the filtergraph specified by @var{filtergraph} and use it to -filter the stream. - -This is an alias for @code{-filter:v}, see the @ref{filter_option,,-filter option}. -@end table - -@section Advanced Video Options - -@table @option -@item -pix_fmt[:@var{stream_specifier}] @var{format} (@emph{input/output,per-stream}) -Set pixel format. Use @code{-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 @var{pix_fmt} is prefixed by a @code{+}, ffmpeg will exit with an error -if the requested pixel format can not be selected, and automatic conversions -inside filtergraphs are disabled. -If @var{pix_fmt} is a single @code{+}, ffmpeg selects the same pixel format -as the input (or graph output) and automatic conversions are disabled. - -@item -sws_flags @var{flags} (@emph{input/output}) -Set SwScaler flags. -@item -vdt @var{n} -Discard threshold. - -@item -rc_override[:@var{stream_specifier}] @var{override} (@emph{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. - -@item -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 -@option{-deinterlace}, but deinterlacing introduces losses. -@item -psnr -Calculate PSNR of compressed frames. -@item -vstats -Dump video coding statistics to @file{vstats_HHMMSS.log}. -@item -vstats_file @var{file} -Dump video coding statistics to @var{file}. -@item -top[:@var{stream_specifier}] @var{n} (@emph{output,per-stream}) -top=1/bottom=0/auto=-1 field first -@item -dc @var{precision} -Intra_dc_precision. -@item -vtag @var{fourcc/tag} (@emph{output}) -Force video tag/fourcc. This is an alias for @code{-tag:v}. -@item -qphist (@emph{global}) -Show QP histogram -@item -vbsf @var{bitstream_filter} -Deprecated see -bsf - -@item -force_key_frames[:@var{stream_specifier}] @var{time}[,@var{time}...] (@emph{output,per-stream}) -@item -force_key_frames[:@var{stream_specifier}] expr:@var{expr} (@emph{output,per-stream}) -Force key frames at the specified timestamps, more precisely at the first -frames after each specified time. - -If the argument is prefixed with @code{expr:}, the string @var{expr} -is interpreted like an expression and is evaluated for each frame. A -key frame is forced in case the evaluation is non-zero. - -If one of the times is "@code{chapters}[@var{delta}]", it is expanded into -the time of the beginning of all chapters in the file, shifted by -@var{delta}, expressed as a time in seconds. -This option can be useful to ensure that a seek point is present at a -chapter mark or any other designated place in the output file. - -For example, to insert a key frame at 5 minutes, plus key frames 0.1 second -before the beginning of every chapter: -@example --force_key_frames 0:05:00,chapters-0.1 -@end example - -The expression in @var{expr} can contain the following constants: -@table @option -@item n -the number of current processed frame, starting from 0 -@item n_forced -the number of forced frames -@item prev_forced_n -the number of the previous forced frame, it is @code{NAN} when no -keyframe was forced yet -@item prev_forced_t -the time of the previous forced frame, it is @code{NAN} when no -keyframe was forced yet -@item t -the time of the current processed frame -@end table - -For example to force a key frame every 5 seconds, you can specify: -@example --force_key_frames expr:gte(t,n_forced*5) -@end example - -To force a key frame 5 seconds after the time of the last forced one, -starting from second 13: -@example --force_key_frames expr:if(isnan(prev_forced_t),gte(t,13),gte(t,prev_forced_t+5)) -@end example - -Note that forcing too many keyframes is very harmful for the lookahead -algorithms of certain encoders: using fixed-GOP options or similar -would be more efficient. - -@item -copyinkf[:@var{stream_specifier}] (@emph{output,per-stream}) -When doing stream copy, copy also non-key frames found at the -beginning. - -@item -hwaccel[:@var{stream_specifier}] @var{hwaccel} (@emph{input,per-stream}) -Use hardware acceleration to decode the matching stream(s). The allowed values -of @var{hwaccel} are: -@table @option -@item none -Do not use any hardware acceleration (the default). - -@item auto -Automatically select the hardware acceleration method. - -@item vdpau -Use VDPAU (Video Decode and Presentation API for Unix) hardware acceleration. -@end table - -This option has no effect if the selected hwaccel is not available or not -supported by the chosen decoder. - -Note that most acceleration methods are intended for playback and will not be -faster than software decoding on modern CPUs. Additionally, @command{ffmpeg} -will usually need to copy the decoded frames from the GPU memory into the system -memory, resulting in further performance loss. This option is thus mainly -useful for testing. - -@item -hwaccel_device[:@var{stream_specifier}] @var{hwaccel_device} (@emph{input,per-stream}) -Select a device to use for hardware acceleration. - -This option only makes sense when the @option{-hwaccel} option is also -specified. Its exact meaning depends on the specific hardware acceleration -method chosen. - -@table @option -@item vdpau -For VDPAU, this option specifies the X11 display/screen to use. If this option -is not specified, the value of the @var{DISPLAY} environment variable is used -@end table -@end table - -@section Audio Options - -@table @option -@item -aframes @var{number} (@emph{output}) -Set the number of audio frames to record. This is an alias for @code{-frames:a}. -@item -ar[:@var{stream_specifier}] @var{freq} (@emph{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. -@item -aq @var{q} (@emph{output}) -Set the audio quality (codec-specific, VBR). This is an alias for -q:a. -@item -ac[:@var{stream_specifier}] @var{channels} (@emph{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. -@item -an (@emph{output}) -Disable audio recording. -@item -acodec @var{codec} (@emph{input/output}) -Set the audio codec. This is an alias for @code{-codec:a}. -@item -sample_fmt[:@var{stream_specifier}] @var{sample_fmt} (@emph{output,per-stream}) -Set the audio sample format. Use @code{-sample_fmts} to get a list -of supported sample formats. - -@item -af @var{filtergraph} (@emph{output}) -Create the filtergraph specified by @var{filtergraph} and use it to -filter the stream. - -This is an alias for @code{-filter:a}, see the @ref{filter_option,,-filter option}. -@end table - -@section Advanced Audio options: - -@table @option -@item -atag @var{fourcc/tag} (@emph{output}) -Force audio tag/fourcc. This is an alias for @code{-tag:a}. -@item -absf @var{bitstream_filter} -Deprecated, see -bsf -@item -guess_layout_max @var{channels} (@emph{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 @command{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. -@end table - -@section Subtitle options: - -@table @option -@item -slang @var{code} -Set the ISO 639 language code (3 letters) of the current subtitle stream. -@item -scodec @var{codec} (@emph{input/output}) -Set the subtitle codec. This is an alias for @code{-codec:s}. -@item -sn (@emph{output}) -Disable subtitle recording. -@item -sbsf @var{bitstream_filter} -Deprecated, see -bsf -@end table - -@section Advanced Subtitle options: - -@table @option - -@item -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. - -Note that this option will delay the output of all data until the next -subtitle packet is decoded: it may increase memory consumption and latency a -lot. - -@item -canvas_size @var{size} -Set the size of the canvas used to render subtitles. - -@end table - -@section Advanced options - -@table @option -@item -map [-]@var{input_file_id}[:@var{stream_specifier}][,@var{sync_file_id}[:@var{stream_specifier}]] | @var{[linklabel]} (@emph{output}) - -Designate one or more input streams as a source for the output file. Each input -stream is identified by the input file index @var{input_file_id} and -the input stream index @var{input_stream_id} within the input -file. Both indices start at 0. If specified, -@var{sync_file_id}:@var{stream_specifier} sets which input stream -is used as a presentation sync reference. - -The first @code{-map} option on the command line specifies the -source for output stream 0, the second @code{-map} option specifies -the source for output stream 1, etc. - -A @code{-} character before the stream identifier creates a "negative" mapping. -It disables matching streams from already created mappings. - -An alternative @var{[linklabel]} form will map outputs from complex filter -graphs (see the @option{-filter_complex} option) to the output file. -@var{linklabel} must correspond to a defined output link label in the graph. - -For example, to map ALL streams from the first input file to output -@example -ffmpeg -i INPUT -map 0 output -@end example - -For example, if you have two audio streams in the first input file, -these streams are identified by "0:0" and "0:1". You can use -@code{-map} to select which streams to place in an output file. For -example: -@example -ffmpeg -i INPUT -map 0:1 out.wav -@end example -will map the input stream in @file{INPUT} identified by "0:1" to -the (single) output stream in @file{out.wav}. - -For example, to select the stream with index 2 from input file -@file{a.mov} (specified by the identifier "0:2"), and stream with -index 6 from input @file{b.mov} (specified by the identifier "1:6"), -and copy them to the output file @file{out.mov}: -@example -ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov -@end example - -To select all video and the third audio stream from an input file: -@example -ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT -@end example - -To map all the streams except the second audio, use negative mappings -@example -ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT -@end example - -Note that using this option disables the default mappings for this output file. - -@item -map_channel [@var{input_file_id}.@var{stream_specifier}.@var{channel_id}|-1][:@var{output_file_id}.@var{stream_specifier}] -Map an audio channel from a given input to an output. If -@var{output_file_id}.@var{stream_specifier} is not set, the audio channel will -be mapped on all the audio streams. - -Using "-1" instead of -@var{input_file_id}.@var{stream_specifier}.@var{channel_id} will map a muted -channel. - -For example, assuming @var{INPUT} is a stereo audio file, you can switch the -two audio channels with the following command: -@example -ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT -@end example - -If you want to mute the first channel and keep the second: -@example -ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT -@end example - -The order of the "-map_channel" option specifies the order of the channels in -the output stream. The output channel layout is guessed from the number of -channels mapped (mono if one "-map_channel", stereo if two, etc.). Using "-ac" -in combination of "-map_channel" makes the channel gain levels to be updated if -input and output channel layouts don't match (for instance two "-map_channel" -options and "-ac 6"). - -You can also extract each channel of an input to specific outputs; the following -command extracts two channels of the @var{INPUT} audio stream (file 0, stream 0) -to the respective @var{OUTPUT_CH0} and @var{OUTPUT_CH1} outputs: -@example -ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1 -@end example - -The following example splits the channels of a stereo input into two separate -streams, which are put into the same output file: -@example -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 -@end example - -Note that currently each output stream can only contain channels from a single -input stream; you can't for example use "-map_channel" to pick multiple input -audio channels contained in different streams (from the same or different files) -and merge them into a single output stream. It is therefore not currently -possible, for example, to turn two separate mono streams into a single stereo -stream. However splitting a stereo stream into two single channel mono streams -is possible. - -If you need this feature, a possible workaround is to use the @emph{amerge} -filter. For example, if you need to merge a media (here @file{input.mkv}) with 2 -mono audio streams into one single stereo channel audio stream (and keep the -video stream), you can use the following command: -@example -ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv -@end example - -@item -map_metadata[:@var{metadata_spec_out}] @var{infile}[:@var{metadata_spec_in}] (@emph{output,per-metadata}) -Set metadata information of the next output file from @var{infile}. Note that -those are file indices (zero-based), not filenames. -Optional @var{metadata_spec_in/out} parameters specify, which metadata to copy. -A metadata specifier can have the following forms: -@table @option -@item @var{g} -global metadata, i.e. metadata that applies to the whole file - -@item @var{s}[:@var{stream_spec}] -per-stream metadata. @var{stream_spec} is a stream specifier as described -in the @ref{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. - -@item @var{c}:@var{chapter_index} -per-chapter metadata. @var{chapter_index} is the zero-based chapter index. - -@item @var{p}:@var{program_index} -per-program metadata. @var{program_index} is the zero-based program index. -@end table -If metadata specifier is omitted, it defaults to global. - -By default, global metadata is copied from the first input file, -per-stream and per-chapter metadata is copied along with streams/chapters. These -default mappings are disabled by creating any mapping of the relevant type. A negative -file index can be used to create a dummy mapping that just disables automatic copying. - -For example to copy metadata from the first stream of the input file to global metadata -of the output file: -@example -ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3 -@end example - -To do the reverse, i.e. copy global metadata to all audio streams: -@example -ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv -@end example -Note that simple @code{0} would work as well in this example, since global -metadata is assumed by default. - -@item -map_chapters @var{input_file_index} (@emph{output}) -Copy chapters from input file with index @var{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. - -@item -benchmark (@emph{global}) -Show benchmarking information at the end of an encode. -Shows CPU time used and maximum memory consumption. -Maximum memory consumption is not supported on all systems, -it will usually display as 0 if not supported. -@item -benchmark_all (@emph{global}) -Show benchmarking information during the encode. -Shows CPU time used in various steps (audio/video encode/decode). -@item -timelimit @var{duration} (@emph{global}) -Exit after ffmpeg has been running for @var{duration} seconds. -@item -dump (@emph{global}) -Dump each input packet to stderr. -@item -hex (@emph{global}) -When dumping packets, also dump the payload. -@item -re (@emph{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 @command{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). -@item -loop_input -Loop over the input stream. Currently it works only for image -streams. This option is used for automatic FFserver testing. -This option is deprecated, use -loop 1. -@item -loop_output @var{number_of_times} -Repeatedly loop output for formats that support looping such as animated GIF -(0 will loop the output infinitely). -This option is deprecated, use -loop. -@item -vsync @var{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. - -@table @option -@item 0, passthrough -Each frame is passed with its timestamp from the demuxer to the muxer. -@item 1, cfr -Frames will be duplicated and dropped to achieve exactly the requested -constant frame rate. -@item 2, vfr -Frames are passed through with their timestamp or dropped so as to -prevent 2 frames from having the same timestamp. -@item drop -As passthrough but destroys all timestamps, making the muxer generate -fresh timestamps based on frame-rate. -@item -1, auto -Chooses between 1 and 2 depending on muxer capabilities. This is the -default method. -@end table - -Note that the timestamps may be further modified by the muxer, after this. -For example, in the case that the format option @option{avoid_negative_ts} -is enabled. - -With -map you can select from which stream the timestamps should be -taken. You can leave either video or audio unchanged and sync the -remaining stream(s) to the unchanged one. - -@item -async @var{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. - -Note that the timestamps may be further modified by the muxer, after this. -For example, in the case that the format option @option{avoid_negative_ts} -is enabled. - -This option has been deprecated. Use the @code{aresample} audio filter instead. - -@item -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. - -Note that, depending on the @option{vsync} option or on specific muxer -processing (e.g. in case the format option @option{avoid_negative_ts} -is enabled) the output timestamps may mismatch with the input -timestamps even when this option is selected. - -@item -copytb @var{mode} -Specify how to set the encoder timebase when stream copying. @var{mode} is an -integer numeric value, and can assume one of the following values: - -@table @option -@item 1 -Use the demuxer timebase. - -The time base is copied to the output encoder from the corresponding input -demuxer. This is sometimes required to avoid non monotonically increasing -timestamps when copying video streams with variable frame rate. - -@item 0 -Use the decoder timebase. - -The time base is copied to the output encoder from the corresponding input -decoder. - -@item -1 -Try to make the choice automatically, in order to generate a sane output. -@end table - -Default value is -1. - -@item -shortest (@emph{output}) -Finish encoding when the shortest input stream ends. -@item -dts_delta_threshold -Timestamp discontinuity delta threshold. -@item -muxdelay @var{seconds} (@emph{input}) -Set the maximum demux-decode delay. -@item -muxpreload @var{seconds} (@emph{input}) -Set the initial demux-decode delay. -@item -streamid @var{output-stream-index}:@var{new-value} (@emph{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. - -For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for -an output mpegts file: -@example -ffmpeg -i infile -streamid 0:33 -streamid 1:36 out.ts -@end example - -@item -bsf[:@var{stream_specifier}] @var{bitstream_filters} (@emph{output,per-stream}) -Set bitstream filters for matching streams. @var{bitstream_filters} is -a comma-separated list of bitstream filters. Use the @code{-bsfs} option -to get the list of bitstream filters. -@example -ffmpeg -i h264.mp4 -c:v copy -bsf:v h264_mp4toannexb -an out.h264 -@end example -@example -ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt -@end example - -@item -tag[:@var{stream_specifier}] @var{codec_tag} (@emph{per-stream}) -Force a tag/fourcc for matching streams. - -@item -timecode @var{hh}:@var{mm}:@var{ss}SEP@var{ff} -Specify Timecode for writing. @var{SEP} is ':' for non drop timecode and ';' -(or '.') for drop. -@example -ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg -@end example - -@anchor{filter_complex_option} -@item -filter_complex @var{filtergraph} (@emph{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 @option{-filter} options. @var{filtergraph} is a description of -the filtergraph, as described in the ``Filtergraph syntax'' section of the -ffmpeg-filters manual. - -Input link labels must refer to input streams using the -@code{[file_index:stream_specifier]} syntax (i.e. the same as @option{-map} -uses). If @var{stream_specifier} matches multiple streams, the first one will be -used. An unlabeled input will be connected to the first unused input stream of -the matching type. - -Output link labels are referred to with @option{-map}. Unlabeled outputs are -added to the first output file. - -Note that with this option it is possible to use only lavfi sources without -normal input files. - -For example, to overlay an image over video -@example -ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map -'[out]' out.mkv -@end example -Here @code{[0:v]} refers to the first video stream in the first input file, -which is linked to the first (main) input of the overlay filter. Similarly the -first video stream in the second input is linked to the second (overlay) input -of overlay. - -Assuming there is only one video stream in each input file, we can omit input -labels, so the above is equivalent to -@example -ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map -'[out]' out.mkv -@end example - -Furthermore we can omit the output label and the single output from the filter -graph will be added to the output file automatically, so we can simply write -@example -ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv -@end example - -To generate 5 seconds of pure red video using lavfi @code{color} source: -@example -ffmpeg -filter_complex 'color=c=red' -t 5 out.mkv -@end example - -@item -lavfi @var{filtergraph} (@emph{global}) -Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or -outputs. Equivalent to @option{-filter_complex}. - -@item -filter_complex_script @var{filename} (@emph{global}) -This option is similar to @option{-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. - -@item -accurate_seek (@emph{input}) -This option enables or disables accurate seeking in input files with the -@option{-ss} option. It is enabled by default, so seeking is accurate when -transcoding. Use @option{-noaccurate_seek} to disable it, which may be useful -e.g. when copying some streams and transcoding the others. - -@item -override_ffserver (@emph{global}) -Overrides the input specifications from @command{ffserver}. Using this -option you can map any input stream to @command{ffserver} and control -many aspects of the encoding from @command{ffmpeg}. Without this -option @command{ffmpeg} will transmit to @command{ffserver} what is -requested by @command{ffserver}. - -The option is intended for cases where features are needed that cannot be -specified to @command{ffserver} but can be to @command{ffmpeg}. - -@end table - -As a special exception, you can use a bitmap subtitle stream as input: it -will be converted into a video with the same size as the largest video in -the file, or 720x576 if no video is present. Note that this is an -experimental and temporary solution. It will be removed once libavfilter has -proper support for subtitles. - -For example, to hardcode subtitles on top of a DVB-T recording stored in -MPEG-TS format, delaying the subtitles by 1 second: -@example -ffmpeg -i input.ts -filter_complex \ - '[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \ - -sn -map '#0x2dc' output.mkv -@end example -(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) - -@section Preset files -A preset file contains a sequence of @var{option}=@var{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 @file{presets} directory in the FFmpeg source tree for examples. - -Preset files are specified with the @code{vpre}, @code{apre}, -@code{spre}, and @code{fpre} options. The @code{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 @code{vpre}, @code{apre}, and -@code{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 @code{vpre}, @code{apre}, and @code{spre} -preset options identifies the preset file to use according to the -following rules: - -First ffmpeg searches for a file named @var{arg}.ffpreset in the -directories @file{$FFMPEG_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in -the datadir defined at configuration time (usually @file{PREFIX/share/ffmpeg}) -or in a @file{ffpresets} folder along the executable on win32, -in that order. For example, if the argument is @code{libvpx-1080p}, it will -search for the file @file{libvpx-1080p.ffpreset}. - -If no such file is found, then ffmpeg will search for a file named -@var{codec_name}-@var{arg}.ffpreset in the above-mentioned -directories, where @var{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 @code{-vcodec libvpx} and use @code{-vpre 1080p}, -then it will search for the file @file{libvpx-1080p.ffpreset}. -@c man end OPTIONS - -@chapter Tips -@c man begin TIPS - -@itemize -@item -For streaming at very low bitrates, use a low frame rate -and a small GOP size. This is especially true for RealVideo where -the Linux player does not seem to be very fast, so it can miss -frames. An example is: - -@example -ffmpeg -g 3 -r 3 -t 10 -b:v 50k -s qcif -f rv10 /tmp/b.rm -@end example - -@item -The parameter 'q' which is displayed while encoding is the current -quantizer. The value 1 indicates that a very good quality could -be achieved. The value 31 indicates the worst quality. If q=31 appears -too often, it means that the encoder cannot compress enough to meet -your bitrate. You must either increase the bitrate, decrease the -frame rate or decrease the frame size. - -@item -If your computer is not fast enough, you can speed up the -compression at the expense of the compression ratio. You can use -'-me zero' to speed up motion estimation, and '-g 0' to disable -motion estimation completely (you have only I-frames, which means it -is about as good as JPEG compression). - -@item -To have very low audio bitrates, reduce the sampling frequency -(down to 22050 Hz for MPEG audio, 22050 or 11025 for AC-3). - -@item -To have a constant quality (but a variable bitrate), use the option -'-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst -quality). - -@end itemize -@c man end TIPS - -@chapter Examples -@c man begin EXAMPLES - -@section Preset files - -A preset file contains a sequence of @var{option=value} pairs, one for -each line, specifying a sequence of options which can be specified also on -the command line. Lines starting with the hash ('#') character are ignored and -are used to provide comments. Empty lines are also ignored. Check the -@file{presets} directory in the FFmpeg source tree for examples. - -Preset files are specified with the @code{pre} option, this option takes a -preset name as input. FFmpeg searches for a file named @var{preset_name}.avpreset in -the directories @file{$AVCONV_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in -the data directory defined at configuration time (usually @file{$PREFIX/share/ffmpeg}) -in that order. For example, if the argument is @code{libx264-max}, it will -search for the file @file{libx264-max.avpreset}. - -@section Video and Audio grabbing - -If you specify the input format and device then ffmpeg can grab video -and audio directly. - -@example -ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg -@end example - -Or with an ALSA audio source (mono input, card id 1) instead of OSS: -@example -ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg -@end example - -Note that you must activate the right video source and channel before -launching ffmpeg with any TV viewer such as -@uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also -have to set the audio recording levels correctly with a -standard mixer. - -@section X11 grabbing - -Grab the X11 display with ffmpeg via - -@example -ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0 /tmp/out.mpg -@end example - -0.0 is display.screen number of your X11 server, same as -the DISPLAY environment variable. - -@example -ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0+10,20 /tmp/out.mpg -@end example - -0.0 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. - -@section Video and Audio file format conversion - -Any supported file format and protocol can serve as input to ffmpeg: - -Examples: -@itemize -@item -You can use YUV files as input: - -@example -ffmpeg -i /tmp/test%d.Y /tmp/out.mpg -@end example - -It will use the files: -@example -/tmp/test0.Y, /tmp/test0.U, /tmp/test0.V, -/tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc... -@end example - -The Y files use twice the resolution of the U and V files. They are -raw files, without header. They can be generated by all decent video -decoders. You must specify the size of the image with the @option{-s} option -if ffmpeg cannot guess it. - -@item -You can input from a raw YUV420P file: - -@example -ffmpeg -i /tmp/test.yuv /tmp/out.avi -@end example - -test.yuv is a file containing raw YUV planar data. Each frame is composed -of the Y plane followed by the U and V planes at half vertical and -horizontal resolution. - -@item -You can output to a raw YUV420P file: - -@example -ffmpeg -i mydivx.avi hugefile.yuv -@end example - -@item -You can set several input files and output files: - -@example -ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg -@end example - -Converts the audio file a.wav and the raw YUV video file a.yuv -to MPEG file a.mpg. - -@item -You can also do audio and video conversions at the same time: - -@example -ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2 -@end example - -Converts a.wav to MPEG audio at 22050 Hz sample rate. - -@item -You can encode to several formats at the same time and define a -mapping from input stream to output streams: - -@example -ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2 -@end example - -Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map -file:index' specifies which input stream is used for each output -stream, in the order of the definition of output streams. - -@item -You can transcode decrypted VOBs: - -@example -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 -@end example - -This is a typical DVD ripping example; the input is a VOB file, the -output an AVI file with MPEG-4 video and MP3 audio. Note that in this -command we use B-frames so the MPEG-4 stream is DivX5 compatible, and -GOP size is 300 which means one intra frame every 10 seconds for 29.97fps -input video. Furthermore, the audio stream is MP3-encoded so you need -to enable LAME support by passing @code{--enable-libmp3lame} to configure. -The mapping is particularly useful for DVD transcoding -to get the desired audio language. - -NOTE: To see the supported input formats, use @code{ffmpeg -formats}. - -@item -You can extract images from a video, or create a video from many images: - -For extracting images from a video: -@example -ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg -@end example - -This will extract one video frame per second from the video and will -output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg}, -etc. Images will be rescaled to fit the new WxH values. - -If you want to extract just a limited number of frames, you can use the -above command in combination with the -vframes or -t option, or in -combination with -ss to start extracting from a certain point in time. - -For creating a video from many images: -@example -ffmpeg -f image2 -i foo-%03d.jpeg -r 12 -s WxH foo.avi -@end example - -The syntax @code{foo-%03d.jpeg} specifies to use a decimal number -composed of three digits padded with zeroes to express the sequence -number. It is the same syntax supported by the C printf function, but -only formats accepting a normal integer are suitable. - -When importing an image sequence, -i also supports expanding -shell-like wildcard patterns (globbing) internally, by selecting the -image2-specific @code{-pattern_type glob} option. - -For example, for creating a video from filenames matching the glob pattern -@code{foo-*.jpeg}: -@example -ffmpeg -f image2 -pattern_type glob -i 'foo-*.jpeg' -r 12 -s WxH foo.avi -@end example - -@item -You can put many streams of the same type in the output: - -@example -ffmpeg -i test1.avi -i test2.avi -map 0:3 -map 0:2 -map 0:1 -map 0:0 -c copy test12.nut -@end example - -The resulting output file @file{test12.avi} will contain first four streams from -the input file in reverse order. - -@item -To force CBR video output: -@example -ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v -@end example - -@item -The four options lmin, lmax, mblmin and mblmax use 'lambda' units, -but you may use the QP2LAMBDA constant to easily convert from 'q' units: -@example -ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext -@end example - -@end itemize -@c man end EXAMPLES - -@include config.texi -@ifset config-all -@ifset config-avutil -@include utils.texi -@end ifset -@ifset config-avcodec -@include codecs.texi -@include bitstream_filters.texi -@end ifset -@ifset config-avformat -@include formats.texi -@include protocols.texi -@end ifset -@ifset config-avdevice -@include devices.texi -@end ifset -@ifset config-swresample -@include resampler.texi -@end ifset -@ifset config-swscale -@include scaler.texi -@end ifset -@ifset config-avfilter -@include filters.texi -@end ifset -@end ifset - -@chapter See Also - -@ifhtml -@ifset config-all -@url{ffmpeg.html,ffmpeg} -@end ifset -@ifset config-not-all -@url{ffmpeg-all.html,ffmpeg-all}, -@end ifset -@url{ffplay.html,ffplay}, @url{ffprobe.html,ffprobe}, @url{ffserver.html,ffserver}, -@url{ffmpeg-utils.html,ffmpeg-utils}, -@url{ffmpeg-scaler.html,ffmpeg-scaler}, -@url{ffmpeg-resampler.html,ffmpeg-resampler}, -@url{ffmpeg-codecs.html,ffmpeg-codecs}, -@url{ffmpeg-bitstream-filters.html,ffmpeg-bitstream-filters}, -@url{ffmpeg-formats.html,ffmpeg-formats}, -@url{ffmpeg-devices.html,ffmpeg-devices}, -@url{ffmpeg-protocols.html,ffmpeg-protocols}, -@url{ffmpeg-filters.html,ffmpeg-filters} -@end ifhtml - -@ifnothtml -@ifset config-all -ffmpeg(1), -@end ifset -@ifset config-not-all -ffmpeg-all(1), -@end ifset -ffplay(1), ffprobe(1), ffserver(1), -ffmpeg-utils(1), ffmpeg-scaler(1), ffmpeg-resampler(1), -ffmpeg-codecs(1), ffmpeg-bitstream-filters(1), ffmpeg-formats(1), -ffmpeg-devices(1), ffmpeg-protocols(1), ffmpeg-filters(1) -@end ifnothtml - -@include authors.texi - -@ignore - -@setfilename ffmpeg -@settitle ffmpeg video converter - -@end ignore - -@bye |