| \input texinfo @c -*- texinfo -*- |
| |
| @settitle ffmpeg Documentation |
| @titlepage |
| @center @titlefont{ffmpeg Documentation} |
| @end titlepage |
| |
| @top |
| |
| @contents |
| |
| @chapter Synopsis |
| |
| The generic syntax is: |
| |
| @example |
| @c man begin SYNOPSIS |
| ffmpeg [global options] [[infile options][@option{-i} @var{infile}]]... @{[outfile options] @var{outfile}@}... |
| @c man end |
| @end example |
| |
| @chapter Description |
| @c man begin DESCRIPTION |
| |
| 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. |
| |
| 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). Allowed number and/or |
| types of streams can be limited by the container format. Selecting, which |
| streams from which inputs go into output, is done either 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. See also 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 64kbit/s: |
| @example |
| ffmpeg -i input.avi -b:v 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 Stream selection |
| @c man begin STREAM SELECTION |
| |
| By default 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 the stream with the most channels, for |
| subtitle it's the first subtitle stream. In the case where several streams of |
| the same type rate equally, the lowest numbered stream is chosen. |
| |
| You can disable some of those defaults by using @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 avtools-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 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 but exit if file 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. |
| |
| @item -fs @var{limit_size} (@emph{output}) |
| Set the file size limit. |
| |
| @item -ss @var{position} (@emph{input/output}) |
| When used as an input option (before @code{-i}), seeks in this input file to |
| @var{position}. When used as an output option (before an output filename), |
| decodes but discards input until the timestamps reach @var{position}. This is |
| slower, but more accurate. |
| |
| @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...]]])|(HH[MM[SS[.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} is |
| codec-dependent. |
| |
| @item -filter[:@var{stream_specifier}] @var{filter_graph} (@emph{output,per-stream}) |
| @var{filter_graph} is a description of the filter graph to apply to |
| the stream. Use @code{-filters} to show all the available filters |
| (including also sources and sinks). |
| @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. On by default. |
| |
| @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 INPUT |
| @end example |
| To extract all attachments to files determined by the @code{filename} tag: |
| @example |
| ffmpeg -dump_attachment:t "" 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), (default = 25). |
| @item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream}) |
| Set frame size. The format is @samp{wxh} (default - same as source). |
| The following abbreviations are recognized: |
| @table @samp |
| @item sqcif |
| 128x96 |
| @item qcif |
| 176x144 |
| @item cif |
| 352x288 |
| @item 4cif |
| 704x576 |
| @item 16cif |
| 1408x1152 |
| @item qqvga |
| 160x120 |
| @item qvga |
| 320x240 |
| @item vga |
| 640x480 |
| @item svga |
| 800x600 |
| @item xga |
| 1024x768 |
| @item uxga |
| 1600x1200 |
| @item qxga |
| 2048x1536 |
| @item sxga |
| 1280x1024 |
| @item qsxga |
| 2560x2048 |
| @item hsxga |
| 5120x4096 |
| @item wvga |
| 852x480 |
| @item wxga |
| 1366x768 |
| @item wsxga |
| 1600x1024 |
| @item wuxga |
| 1920x1200 |
| @item woxga |
| 2560x1600 |
| @item wqsxga |
| 3200x2048 |
| @item wquxga |
| 3840x2400 |
| @item whsxga |
| 6400x4096 |
| @item whuxga |
| 7680x4800 |
| @item cga |
| 320x200 |
| @item ega |
| 640x350 |
| @item hd480 |
| 852x480 |
| @item hd720 |
| 1280x720 |
| @item hd1080 |
| 1920x1080 |
| @end table |
| |
| @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. |
| |
| @item -croptop @var{size} |
| @item -cropbottom @var{size} |
| @item -cropleft @var{size} |
| @item -cropright @var{size} |
| All the crop options have been removed. Use -vf |
| crop=width:height:x:y instead. |
| |
| @item -padtop @var{size} |
| @item -padbottom @var{size} |
| @item -padleft @var{size} |
| @item -padright @var{size} |
| @item -padcolor @var{hex_color} |
| All the pad options have been removed. Use -vf |
| pad=width:height:x:y:color instead. |
| |
| @item -vn (@emph{output}) |
| Disable video recording. |
| @item -bt @var{tolerance} |
| Set video bitrate tolerance (in bits, default 4000k). |
| Has a minimum value of: (target_bitrate/target_framerate). |
| In 1-pass mode, bitrate tolerance specifies how far ratecontrol is |
| willing to deviate from the target average bitrate value. This is |
| not related to min/max bitrate. Lowering tolerance too much has |
| an adverse effect on quality. |
| @item -maxrate @var{bitrate} |
| Set max video bitrate (in bit/s). |
| Requires -bufsize to be set. |
| @item -minrate @var{bitrate} |
| Set min video bitrate (in bit/s). |
| Most useful in setting up a CBR encode: |
| @example |
| ffmpeg -i myfile.avi -b:v 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v |
| @end example |
| It is of little use elsewise. |
| @item -bufsize @var{size} |
| Set video buffer verifier buffer size (in bits). |
| @item -vcodec @var{codec} (@emph{output}) |
| Set the video codec. This is an alias for @code{-codec:v}. |
| @item -same_quant |
| Use same quantizer as source (implies VBR). |
| |
| Note that this is NOT SAME QUALITY. Do not use this option unless you know you |
| need it. |
| |
| @item -pass @var{n} |
| 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{prefix} (@emph{global}) |
| 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 |
| |
| Note that this option is overwritten by a local option of the same name |
| when using @code{-vcodec libx264}. That option maps to the x264 option stats |
| which has a different syntax. |
| |
| @item -vlang @var{code} |
| Set the ISO 639 language code (3 letters) of the current video stream. |
| |
| @item -vf @var{filter_graph} (@emph{output}) |
| @var{filter_graph} is a description of the filter graph to apply to |
| the input video. |
| Use the option "-filters" to show all the available filters (including |
| also sources and sinks). This is an alias for @code{-filter:v}. |
| |
| @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. |
| @item -sws_flags @var{flags} (@emph{input/output}) |
| Set SwScaler flags. |
| @item -g @var{gop_size} |
| Set the group of pictures size. |
| @item -intra |
| deprecated, use -g 1 |
| @item -vdt @var{n} |
| Discard threshold. |
| @item -qmin @var{q} |
| minimum video quantizer scale (VBR) |
| @item -qmax @var{q} |
| maximum video quantizer scale (VBR) |
| @item -qdiff @var{q} |
| maximum difference between the quantizer scales (VBR) |
| @item -qblur @var{blur} |
| video quantizer scale blur (VBR) (range 0.0 - 1.0) |
| @item -qcomp @var{compression} |
| video quantizer scale compression (VBR) (default 0.5). |
| Constant of ratecontrol equation. Recommended range for default rc_eq: 0.0-1.0 |
| |
| @item -lmin @var{lambda} |
| minimum video lagrange factor (VBR) |
| @item -lmax @var{lambda} |
| max video lagrange factor (VBR) |
| @item -mblmin @var{lambda} |
| minimum macroblock quantizer scale (VBR) |
| @item -mblmax @var{lambda} |
| maximum macroblock quantizer scale (VBR) |
| |
| These four options (lmin, lmax, mblmin, 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 |
| |
| @item -rc_init_cplx @var{complexity} |
| initial complexity for single pass encoding |
| @item -b_qfactor @var{factor} |
| qp factor between P- and B-frames |
| @item -i_qfactor @var{factor} |
| qp factor between P- and I-frames |
| @item -b_qoffset @var{offset} |
| qp offset between P- and B-frames |
| @item -i_qoffset @var{offset} |
| qp offset between P- and I-frames |
| @item -rc_eq @var{equation} |
| Set rate control equation (see section "Expression Evaluation") |
| (default = @code{tex^qComp}). |
| |
| When computing the rate control equation expression, besides the |
| standard functions defined in the section "Expression Evaluation", the |
| following functions are available: |
| @table @var |
| @item bits2qp(bits) |
| @item qp2bits(qp) |
| @end table |
| |
| and the following constants are available: |
| @table @var |
| @item iTex |
| @item pTex |
| @item tex |
| @item mv |
| @item fCode |
| @item iCount |
| @item mcVar |
| @item var |
| @item isI |
| @item isP |
| @item isB |
| @item avgQP |
| @item qComp |
| @item avgIITex |
| @item avgPITex |
| @item avgPPTex |
| @item avgBPTex |
| @item avgTex |
| @end table |
| |
| @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 -me_method @var{method} |
| Set motion estimation method to @var{method}. |
| Available methods are (from lowest to best quality): |
| @table @samp |
| @item zero |
| Try just the (0, 0) vector. |
| @item phods |
| @item log |
| @item x1 |
| @item hex |
| @item umh |
| @item epzs |
| (default method) |
| @item full |
| exhaustive search (slow and marginally better than epzs) |
| @end table |
| |
| @item -dct_algo @var{algo} |
| Set DCT algorithm to @var{algo}. Available values are: |
| @table @samp |
| @item 0 |
| FF_DCT_AUTO (default) |
| @item 1 |
| FF_DCT_FASTINT |
| @item 2 |
| FF_DCT_INT |
| @item 3 |
| FF_DCT_MMX |
| @item 4 |
| FF_DCT_MLIB |
| @item 5 |
| FF_DCT_ALTIVEC |
| @end table |
| |
| @item -idct_algo @var{algo} |
| Set IDCT algorithm to @var{algo}. Available values are: |
| @table @samp |
| @item 0 |
| FF_IDCT_AUTO (default) |
| @item 1 |
| FF_IDCT_INT |
| @item 2 |
| FF_IDCT_SIMPLE |
| @item 3 |
| FF_IDCT_SIMPLEMMX |
| @item 4 |
| FF_IDCT_LIBMPEG2MMX |
| @item 5 |
| FF_IDCT_PS2 |
| @item 6 |
| FF_IDCT_MLIB |
| @item 7 |
| FF_IDCT_ARM |
| @item 8 |
| FF_IDCT_ALTIVEC |
| @item 9 |
| FF_IDCT_SH4 |
| @item 10 |
| FF_IDCT_SIMPLEARM |
| @end table |
| |
| @item -er @var{n} |
| Set error resilience to @var{n}. |
| @table @samp |
| @item 1 |
| FF_ER_CAREFUL (default) |
| @item 2 |
| FF_ER_COMPLIANT |
| @item 3 |
| FF_ER_AGGRESSIVE |
| @item 4 |
| FF_ER_VERY_AGGRESSIVE |
| @end table |
| |
| @item -ec @var{bit_mask} |
| Set error concealment to @var{bit_mask}. @var{bit_mask} is a bit mask of |
| the following values: |
| @table @samp |
| @item 1 |
| FF_EC_GUESS_MVS (default = enabled) |
| @item 2 |
| FF_EC_DEBLOCK (default = enabled) |
| @end table |
| |
| @item -bf @var{frames} |
| Use 'frames' B-frames (supported for MPEG-1, MPEG-2 and MPEG-4). |
| @item -mbd @var{mode} |
| macroblock decision |
| @table @samp |
| @item 0 |
| FF_MB_DECISION_SIMPLE: Use mb_cmp (cannot change it yet in ffmpeg). |
| @item 1 |
| FF_MB_DECISION_BITS: Choose the one which needs the fewest bits. |
| @item 2 |
| FF_MB_DECISION_RD: rate distortion |
| @end table |
| |
| @item -4mv |
| Use four motion vector by macroblock (MPEG-4 only). |
| @item -part |
| Use data partitioning (MPEG-4 only). |
| @item -bug @var{param} |
| Work around encoder bugs that are not auto-detected. |
| @item -strict @var{strictness} |
| How strictly to follow the standards. |
| @item -aic |
| Enable Advanced intra coding (h263+). |
| @item -umv |
| Enable Unlimited Motion Vector (h263+) |
| |
| @item -deinterlace |
| Deinterlace pictures. |
| @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}) |
| Force key frames at the specified timestamps, more precisely at the first |
| frames after each specified time. |
| 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. |
| The timestamps must be specified in ascending order. |
| |
| @item -copyinkf[:@var{stream_specifier}] (@emph{output,per-stream}) |
| When doing stream copy, copy also non-key frames found at the |
| beginning. |
| @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. |
| @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 -audio_service_type @var{type} |
| Set the type of service that the audio stream contains. |
| @table @option |
| @item ma |
| Main Audio Service (default) |
| @item ef |
| Effects |
| @item vi |
| Visually Impaired |
| @item hi |
| Hearing Impaired |
| @item di |
| Dialogue |
| @item co |
| Commentary |
| @item em |
| Emergency |
| @item vo |
| Voice Over |
| @item ka |
| Karaoke |
| @end table |
| @item -absf @var{bitstream_filter} |
| Deprecated, see -bsf |
| @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 Audio/Video grab options |
| |
| @table @option |
| @item -isync (@emph{global}) |
| Synchronize read on input. |
| @end table |
| |
| @section Advanced options |
| |
| @table @option |
| @item -map [-]@var{input_file_id}[:@var{stream_specifier}][,@var{sync_file_id}[:@var{stream_specifier}]] (@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. |
| |
| 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} are 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 |
| channel layouts don't match (for instance two "-map_channel" options and "-ac |
| 6"). |
| |
| You can also extract each channel of an @var{INPUT} to specific outputs; the |
| following command extract each channel of the audio stream (file 0, stream 0) |
| to the respective @var{OUTPUT_CH0} and @var{OUTPUT_CH1}: |
| @example |
| ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1 |
| @end example |
| |
| The following example split the channels of a stereo input into streams: |
| |
| @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 spliting a stereo stream into two single channel mono streams |
| is possible. |
| |
| @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 -debug @var{category} |
| Print specific debug info. |
| @var{category} is a number or a string containing one of the following values: |
| @table @samp |
| @item bitstream |
| @item buffers |
| picture buffer allocations |
| @item bugs |
| @item dct_coeff |
| @item er |
| error recognition |
| @item mb_type |
| macroblock (MB) type |
| @item mmco |
| memory management control operations (H.264) |
| @item mv |
| motion vector |
| @item pict |
| picture info |
| @item pts |
| @item qp |
| per-block quantization parameter (QP) |
| @item rc |
| rate control |
| @item skip |
| @item startcode |
| @item thread_ops |
| threading operations |
| @item vis_mb_type |
| visualize block types |
| @item vis_qp |
| visualize quantization parameter (QP), lower QP are tinted greener |
| @end table |
| @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 -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 -ps @var{size} |
| Set RTP payload size in bytes. |
| @item -re (@emph{input}) |
| Read input at native frame rate. Mainly used to simulate a grab device. |
| @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 -threads @var{count} |
| Thread count. |
| @item -vsync @var{parameter} |
| Video sync method. |
| |
| @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 framerate. |
| @item 2, vfr |
| Frames are passed through with their timestamp or dropped so as to |
| prevent 2 frames from having the same timestamp. |
| @item -1, auto |
| Chooses between 1 and 2 depending on muxer capabilities. This is the |
| default method. |
| @end table |
| |
| 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. |
| @item -copyts |
| Copy timestamps from input to output. |
| @item -copytb |
| Copy input stream time base from input to output when stream copying. |
| @item -shortest |
| 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{bistream_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 -vbsf h264_mp4toannexb -an out.h264 |
| @end example |
| @example |
| ffmpeg -i file.mov -an -vn -sbsf 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 |
| @end table |
| |
| @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{libx264-max}, it will |
| search for the file @file{libx264-max.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 libx264} and use @code{-vpre max}, |
| then it will search for the file @file{libx264-max.ffpreset}. |
| @c man end OPTIONS |
| |
| @chapter Tips |
| @c man begin TIPS |
| |
| @itemize |
| @item |
| For streaming at very low bitrate application, 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 '-intra' 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 -s cif -r 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 -s cif -r 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. |
| |
| @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. |
| |
| @end itemize |
| @c man end EXAMPLES |
| |
| @include eval.texi |
| @include decoders.texi |
| @include encoders.texi |
| @include demuxers.texi |
| @include muxers.texi |
| @include indevs.texi |
| @include outdevs.texi |
| @include protocols.texi |
| @include bitstream_filters.texi |
| @include filters.texi |
| @include metadata.texi |
| |
| @ignore |
| |
| @setfilename ffmpeg |
| @settitle ffmpeg video converter |
| |
| @c man begin SEEALSO |
| ffplay(1), ffprobe(1), ffserver(1) and the FFmpeg HTML documentation |
| @c man end |
| |
| @c man begin AUTHORS |
| See git history |
| @c man end |
| |
| @end ignore |
| |
| @bye |