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| author | Indrajith K L | 2022-12-03 17:00:20 +0530 |
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diff --git a/ffmpeg/doc/ffmpeg.html b/ffmpeg/doc/ffmpeg.html new file mode 100644 index 0000000..186427b --- /dev/null +++ b/ffmpeg/doc/ffmpeg.html @@ -0,0 +1,3065 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Created by GNU Texinfo 6.8, https://www.gnu.org/software/texinfo/ --> + <head> + <meta charset="utf-8"> + <title> + ffmpeg Documentation + </title> + <meta name="viewport" content="width=device-width,initial-scale=1.0"> + <link rel="stylesheet" type="text/css" href="bootstrap.min.css"> + <link rel="stylesheet" type="text/css" href="style.min.css"> + </head> + <body> + <div class="container"> + <h1> + ffmpeg Documentation + </h1> +<div align="center"> +</div> + + +<a name="SEC_Top"></a> + +<div class="Contents_element" id="SEC_Contents"> +<h2 class="contents-heading">Table of Contents</h2> + +<div class="contents"> + +<ul class="no-bullet"> + <li><a id="toc-Synopsis" href="#Synopsis">1 Synopsis</a></li> + <li><a id="toc-Description" href="#Description">2 Description</a></li> + <li><a id="toc-Detailed-description" href="#Detailed-description">3 Detailed description</a> + <ul class="no-bullet"> + <li><a id="toc-Filtering" href="#Filtering">3.1 Filtering</a> + <ul class="no-bullet"> + <li><a id="toc-Simple-filtergraphs" href="#Simple-filtergraphs">3.1.1 Simple filtergraphs</a></li> + <li><a id="toc-Complex-filtergraphs" href="#Complex-filtergraphs">3.1.2 Complex filtergraphs</a></li> + </ul></li> + <li><a id="toc-Stream-copy" href="#Stream-copy">3.2 Stream copy</a></li> + </ul></li> + <li><a id="toc-Stream-selection" href="#Stream-selection">4 Stream selection</a> + <ul class="no-bullet"> + <li><a id="toc-Description-1" href="#Description-1">4.1 Description</a> + <ul class="no-bullet"> + <li><a id="toc-Automatic-stream-selection" href="#Automatic-stream-selection">4.1.1 Automatic stream selection</a></li> + <li><a id="toc-Manual-stream-selection" href="#Manual-stream-selection">4.1.2 Manual stream selection</a></li> + <li><a id="toc-Complex-filtergraphs-1" href="#Complex-filtergraphs-1">4.1.3 Complex filtergraphs</a></li> + <li><a id="toc-Stream-handling" href="#Stream-handling">4.1.4 Stream handling</a></li> + </ul></li> + <li><a id="toc-Examples" href="#Examples">4.2 Examples</a></li> + </ul></li> + <li><a id="toc-Options" href="#Options">5 Options</a> + <ul class="no-bullet"> + <li><a id="toc-Stream-specifiers-1" href="#Stream-specifiers-1">5.1 Stream specifiers</a></li> + <li><a id="toc-Generic-options" href="#Generic-options">5.2 Generic options</a></li> + <li><a id="toc-AVOptions" href="#AVOptions">5.3 AVOptions</a></li> + <li><a id="toc-Main-options" href="#Main-options">5.4 Main options</a></li> + <li><a id="toc-Video-Options" href="#Video-Options">5.5 Video Options</a></li> + <li><a id="toc-Advanced-Video-options" href="#Advanced-Video-options">5.6 Advanced Video options</a></li> + <li><a id="toc-Audio-Options" href="#Audio-Options">5.7 Audio Options</a></li> + <li><a id="toc-Advanced-Audio-options" href="#Advanced-Audio-options">5.8 Advanced Audio options</a></li> + <li><a id="toc-Subtitle-options" href="#Subtitle-options">5.9 Subtitle options</a></li> + <li><a id="toc-Advanced-Subtitle-options" href="#Advanced-Subtitle-options">5.10 Advanced Subtitle options</a></li> + <li><a id="toc-Advanced-options" href="#Advanced-options">5.11 Advanced options</a></li> + <li><a id="toc-Preset-files" href="#Preset-files">5.12 Preset files</a> + <ul class="no-bullet"> + <li><a id="toc-ffpreset-files" href="#ffpreset-files">5.12.1 ffpreset files</a></li> + <li><a id="toc-avpreset-files" href="#avpreset-files">5.12.2 avpreset files</a></li> + </ul></li> + </ul></li> + <li><a id="toc-Examples-1" href="#Examples-1">6 Examples</a> + <ul class="no-bullet"> + <li><a id="toc-Video-and-Audio-grabbing" href="#Video-and-Audio-grabbing">6.1 Video and Audio grabbing</a></li> + <li><a id="toc-X11-grabbing" href="#X11-grabbing">6.2 X11 grabbing</a></li> + <li><a id="toc-Video-and-Audio-file-format-conversion" href="#Video-and-Audio-file-format-conversion">6.3 Video and Audio file format conversion</a></li> + </ul></li> + <li><a id="toc-See-Also" href="#See-Also">7 See Also</a></li> + <li><a id="toc-Authors" href="#Authors">8 Authors</a></li> +</ul> +</div> +</div> + +<a name="Synopsis"></a> +<h2 class="chapter">1 Synopsis<span class="pull-right"><a class="anchor hidden-xs" href="#Synopsis" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Synopsis" aria-hidden="true">TOC</a></span></h2> + +<p>ffmpeg [<var>global_options</var>] {[<var>input_file_options</var>] -i <samp>input_url</samp>} ... {[<var>output_file_options</var>] <samp>output_url</samp>} ... +</p> +<a name="Description"></a> +<h2 class="chapter">2 Description<span class="pull-right"><a class="anchor hidden-xs" href="#Description" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Description" aria-hidden="true">TOC</a></span></h2> + +<p><code>ffmpeg</code> 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. +</p> +<p><code>ffmpeg</code> reads from an arbitrary number of input "files" (which can be regular +files, pipes, network streams, grabbing devices, etc.), specified by the +<code>-i</code> option, and writes to an arbitrary number of output "files", which are +specified by a plain output url. Anything found on the command line which +cannot be interpreted as an option is considered to be an output url. +</p> +<p>Each input or output url 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</code> option (see the Stream selection chapter). +</p> +<p>To refer to input files in options, you must use their indices (0-based). E.g. +the first input file is <code>0</code>, the second is <code>1</code>, etc. Similarly, streams +within a file are referred to by their indices. E.g. <code>2:3</code> refers to the +fourth stream in the third input file. Also see the Stream specifiers chapter. +</p> +<p>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. +</p> +<p>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. +</p> +<ul> +<li> To set the video bitrate of the output file to 64 kbit/s: +<div class="example"> +<pre class="example">ffmpeg -i input.avi -b:v 64k -bufsize 64k output.avi +</pre></div> + +</li><li> To force the frame rate of the output file to 24 fps: +<div class="example"> +<pre class="example">ffmpeg -i input.avi -r 24 output.avi +</pre></div> + +</li><li> 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: +<div class="example"> +<pre class="example">ffmpeg -r 1 -i input.m2v -r 24 output.avi +</pre></div> +</li></ul> + +<p>The format option may be needed for raw input files. +</p> + +<a name="Detailed-description"></a> +<h2 class="chapter">3 Detailed description<span class="pull-right"><a class="anchor hidden-xs" href="#Detailed-description" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Detailed-description" aria-hidden="true">TOC</a></span></h2> + +<p>The transcoding process in <code>ffmpeg</code> for each output can be described by +the following diagram: +</p> +<pre class="verbatim"> _______ ______________ +| | | | +| input | demuxer | encoded data | decoder +| file | ---------> | packets | -----+ +|_______| |______________| | + v + _________ + | | + | decoded | + | frames | + |_________| + ________ ______________ | +| | | | | +| output | <-------- | encoded data | <----+ +| file | muxer | packets | encoder +|________| |______________| + + +</pre> +<p><code>ffmpeg</code> calls the libavformat library (containing demuxers) to read +input files and get packets containing encoded data from them. When there are +multiple input files, <code>ffmpeg</code> tries to keep them synchronized by +tracking lowest timestamp on any active input stream. +</p> +<p>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. +</p> +<a name="Filtering"></a> +<h3 class="section">3.1 Filtering<span class="pull-right"><a class="anchor hidden-xs" href="#Filtering" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Filtering" aria-hidden="true">TOC</a></span></h3> +<p>Before encoding, <code>ffmpeg</code> can process raw audio and video frames using +filters from the libavfilter library. Several chained filters form a filter +graph. <code>ffmpeg</code> distinguishes between two types of filtergraphs: +simple and complex. +</p> +<a name="Simple-filtergraphs"></a> +<h4 class="subsection">3.1.1 Simple filtergraphs<span class="pull-right"><a class="anchor hidden-xs" href="#Simple-filtergraphs" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Simple-filtergraphs" aria-hidden="true">TOC</a></span></h4> +<p>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: +</p> +<pre class="verbatim"> _________ ______________ +| | | | +| decoded | | encoded data | +| frames |\ _ | packets | +|_________| \ /||______________| + \ __________ / + simple _\|| | / encoder + filtergraph | filtered |/ + | frames | + |__________| + +</pre> +<p>Simple filtergraphs are configured with the per-stream <samp>-filter</samp> option +(with <samp>-vf</samp> and <samp>-af</samp> aliases for video and audio respectively). +A simple filtergraph for video can look for example like this: +</p> +<pre class="verbatim"> _______ _____________ _______ ________ +| | | | | | | | +| input | ---> | deinterlace | ---> | scale | ---> | output | +|_______| |_____________| |_______| |________| + +</pre> +<p>Note that some filters change frame properties but not frame contents. E.g. the +<code>fps</code> filter in the example above changes number of frames, but does not +touch the frame contents. Another example is the <code>setpts</code> filter, which +only sets timestamps and otherwise passes the frames unchanged. +</p> +<a name="Complex-filtergraphs"></a> +<h4 class="subsection">3.1.2 Complex filtergraphs<span class="pull-right"><a class="anchor hidden-xs" href="#Complex-filtergraphs" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Complex-filtergraphs" aria-hidden="true">TOC</a></span></h4> +<p>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: +</p> +<pre class="verbatim"> _________ +| | +| input 0 |\ __________ +|_________| \ | | + \ _________ /| output 0 | + \ | | / |__________| + _________ \| complex | / +| | | |/ +| input 1 |---->| filter |\ +|_________| | | \ __________ + /| graph | \ | | + / | | \| output 1 | + _________ / |_________| |__________| +| | / +| input 2 |/ +|_________| + +</pre> +<p>Complex filtergraphs are configured with the <samp>-filter_complex</samp> option. +Note that this option is global, since a complex filtergraph, by its nature, +cannot be unambiguously associated with a single stream or file. +</p> +<p>The <samp>-lavfi</samp> option is equivalent to <samp>-filter_complex</samp>. +</p> +<p>A trivial example of a complex filtergraph is the <code>overlay</code> 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</code> filter. +</p> +<a name="Stream-copy"></a> +<h3 class="section">3.2 Stream copy<span class="pull-right"><a class="anchor hidden-xs" href="#Stream-copy" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Stream-copy" aria-hidden="true">TOC</a></span></h3> +<p>Stream copy is a mode selected by supplying the <code>copy</code> parameter to the +<samp>-codec</samp> option. It makes <code>ffmpeg</code> 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: +</p> +<pre class="verbatim"> _______ ______________ ________ +| | | | | | +| input | demuxer | encoded data | muxer | output | +| file | ---------> | packets | -------> | file | +|_______| |______________| |________| + +</pre> +<p>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. +</p> + +<a name="Stream-selection"></a> +<h2 class="chapter">4 Stream selection<span class="pull-right"><a class="anchor hidden-xs" href="#Stream-selection" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Stream-selection" aria-hidden="true">TOC</a></span></h2> + +<p><code>ffmpeg</code> provides the <code>-map</code> option for manual control of stream selection in each +output file. Users can skip <code>-map</code> and let ffmpeg perform automatic stream selection as +described below. The <code>-vn / -an / -sn / -dn</code> options can be used to skip inclusion of +video, audio, subtitle and data streams respectively, whether manually mapped or automatically +selected, except for those streams which are outputs of complex filtergraphs. +</p> +<a name="Description-1"></a> +<h3 class="section">4.1 Description<span class="pull-right"><a class="anchor hidden-xs" href="#Description-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Description-1" aria-hidden="true">TOC</a></span></h3> +<p>The sub-sections that follow describe the various rules that are involved in stream selection. +The examples that follow next show how these rules are applied in practice. +</p> +<p>While every effort is made to accurately reflect the behavior of the program, FFmpeg is under +continuous development and the code may have changed since the time of this writing. +</p> +<a name="Automatic-stream-selection"></a> +<h4 class="subsection">4.1.1 Automatic stream selection<span class="pull-right"><a class="anchor hidden-xs" href="#Automatic-stream-selection" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Automatic-stream-selection" aria-hidden="true">TOC</a></span></h4> + +<p>In the absence of any map options for a particular output file, ffmpeg inspects the output +format to check which type of streams can be included in it, viz. video, audio and/or +subtitles. For each acceptable stream type, ffmpeg will pick one stream, when available, +from among all the inputs. +</p> +<p>It will select that stream based upon the following criteria: +</p><ul> +<li> for video, it is the stream with the highest resolution, +</li><li> for audio, it is the stream with the most channels, +</li><li> for subtitles, it is the first subtitle stream found but there’s a caveat. +The output format’s default subtitle encoder can be either text-based or image-based, +and only a subtitle stream of the same type will be chosen. +</li></ul> + +<p>In the case where several streams of the same type rate equally, the stream with the lowest +index is chosen. +</p> +<p>Data or attachment streams are not automatically selected and can only be included +using <code>-map</code>. +</p><a name="Manual-stream-selection"></a> +<h4 class="subsection">4.1.2 Manual stream selection<span class="pull-right"><a class="anchor hidden-xs" href="#Manual-stream-selection" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Manual-stream-selection" aria-hidden="true">TOC</a></span></h4> + +<p>When <code>-map</code> is used, only user-mapped streams are included in that output file, +with one possible exception for filtergraph outputs described below. +</p> +<a name="Complex-filtergraphs-1"></a> +<h4 class="subsection">4.1.3 Complex filtergraphs<span class="pull-right"><a class="anchor hidden-xs" href="#Complex-filtergraphs-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Complex-filtergraphs-1" aria-hidden="true">TOC</a></span></h4> + +<p>If there are any complex filtergraph output streams with unlabeled pads, they will be added +to the first output file. This will lead to a fatal error if the stream type is not supported +by the output format. In the absence of the map option, the inclusion of these streams leads +to the automatic stream selection of their types being skipped. If map options are present, +these filtergraph streams are included in addition to the mapped streams. +</p> +<p>Complex filtergraph output streams with labeled pads must be mapped once and exactly once. +</p> +<a name="Stream-handling"></a> +<h4 class="subsection">4.1.4 Stream handling<span class="pull-right"><a class="anchor hidden-xs" href="#Stream-handling" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Stream-handling" aria-hidden="true">TOC</a></span></h4> + +<p>Stream handling is independent of stream selection, with an exception for subtitles described +below. Stream handling is set via the <code>-codec</code> option addressed to streams within a +specific <em>output</em> file. In particular, codec options are applied by ffmpeg after the +stream selection process and thus do not influence the latter. If no <code>-codec</code> option is +specified for a stream type, ffmpeg will select the default encoder registered by the output +file muxer. +</p> +<p>An exception exists for subtitles. If a subtitle encoder is specified for an output file, the +first subtitle stream found of any type, text or image, will be included. ffmpeg does not validate +if the specified encoder can convert the selected stream or if the converted stream is acceptable +within the output format. This applies generally as well: when the user sets an encoder manually, +the stream selection process cannot check if the encoded stream can be muxed into the output file. +If it cannot, ffmpeg will abort and <em>all</em> output files will fail to be processed. +</p> +<a name="Examples"></a> +<h3 class="section">4.2 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples" aria-hidden="true">TOC</a></span></h3> + +<p>The following examples illustrate the behavior, quirks and limitations of ffmpeg’s stream +selection methods. +</p> +<p>They assume the following three input files. +</p> +<pre class="verbatim"> +input file 'A.avi' + stream 0: video 640x360 + stream 1: audio 2 channels + +input file 'B.mp4' + stream 0: video 1920x1080 + stream 1: audio 2 channels + stream 2: subtitles (text) + stream 3: audio 5.1 channels + stream 4: subtitles (text) + +input file 'C.mkv' + stream 0: video 1280x720 + stream 1: audio 2 channels + stream 2: subtitles (image) +</pre> +<a name="Example_003a-automatic-stream-selection"></a> +<div class="example"> +<pre class="example">ffmpeg -i A.avi -i B.mp4 out1.mkv out2.wav -map 1:a -c:a copy out3.mov +</pre></div> +<p>There are three output files specified, and for the first two, no <code>-map</code> options +are set, so ffmpeg will select streams for these two files automatically. +</p> +<p><samp>out1.mkv</samp> is a Matroska container file and accepts video, audio and subtitle streams, +so ffmpeg will try to select one of each type.<br> +For video, it will select <code>stream 0</code> from <samp>B.mp4</samp>, which has the highest +resolution among all the input video streams.<br> +For audio, it will select <code>stream 3</code> from <samp>B.mp4</samp>, since it has the greatest +number of channels.<br> +For subtitles, it will select <code>stream 2</code> from <samp>B.mp4</samp>, which is the first subtitle +stream from among <samp>A.avi</samp> and <samp>B.mp4</samp>. +</p> +<p><samp>out2.wav</samp> accepts only audio streams, so only <code>stream 3</code> from <samp>B.mp4</samp> is +selected. +</p> +<p>For <samp>out3.mov</samp>, since a <code>-map</code> option is set, no automatic stream selection will +occur. The <code>-map 1:a</code> option will select all audio streams from the second input +<samp>B.mp4</samp>. No other streams will be included in this output file. +</p> +<p>For the first two outputs, all included streams will be transcoded. The encoders chosen will +be the default ones registered by each output format, which may not match the codec of the +selected input streams. +</p> +<p>For the third output, codec option for audio streams has been set +to <code>copy</code>, so no decoding-filtering-encoding operations will occur, or <em>can</em> occur. +Packets of selected streams shall be conveyed from the input file and muxed within the output +file. +</p> +<a name="Example_003a-automatic-subtitles-selection"></a> +<div class="example"> +<pre class="example">ffmpeg -i C.mkv out1.mkv -c:s dvdsub -an out2.mkv +</pre></div> +<p>Although <samp>out1.mkv</samp> is a Matroska container file which accepts subtitle streams, only a +video and audio stream shall be selected. The subtitle stream of <samp>C.mkv</samp> is image-based +and the default subtitle encoder of the Matroska muxer is text-based, so a transcode operation +for the subtitles is expected to fail and hence the stream isn’t selected. However, in +<samp>out2.mkv</samp>, a subtitle encoder is specified in the command and so, the subtitle stream is +selected, in addition to the video stream. The presence of <code>-an</code> disables audio stream +selection for <samp>out2.mkv</samp>. +</p> +<a name="Example_003a-unlabeled-filtergraph-outputs"></a> +<div class="example"> +<pre class="example">ffmpeg -i A.avi -i C.mkv -i B.mp4 -filter_complex "overlay" out1.mp4 out2.srt +</pre></div> +<p>A filtergraph is setup here using the <code>-filter_complex</code> option and consists of a single +video filter. The <code>overlay</code> filter requires exactly two video inputs, but none are +specified, so the first two available video streams are used, those of <samp>A.avi</samp> and +<samp>C.mkv</samp>. The output pad of the filter has no label and so is sent to the first output file +<samp>out1.mp4</samp>. Due to this, automatic selection of the video stream is skipped, which would +have selected the stream in <samp>B.mp4</samp>. The audio stream with most channels viz. <code>stream 3</code> +in <samp>B.mp4</samp>, is chosen automatically. No subtitle stream is chosen however, since the MP4 +format has no default subtitle encoder registered, and the user hasn’t specified a subtitle encoder. +</p> +<p>The 2nd output file, <samp>out2.srt</samp>, only accepts text-based subtitle streams. So, even though +the first subtitle stream available belongs to <samp>C.mkv</samp>, it is image-based and hence skipped. +The selected stream, <code>stream 2</code> in <samp>B.mp4</samp>, is the first text-based subtitle stream. +</p> +<a name="Example_003a-labeled-filtergraph-outputs"></a> +<div class="example"> +<pre class="example">ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0[outv];overlay;aresample" \ + -map '[outv]' -an out1.mp4 \ + out2.mkv \ + -map '[outv]' -map 1:a:0 out3.mkv +</pre></div> + +<p>The above command will fail, as the output pad labelled <code>[outv]</code> has been mapped twice. +None of the output files shall be processed. +</p> +<div class="example"> +<pre class="example">ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0[outv];overlay;aresample" \ + -an out1.mp4 \ + out2.mkv \ + -map 1:a:0 out3.mkv +</pre></div> + +<p>This command above will also fail as the hue filter output has a label, <code>[outv]</code>, +and hasn’t been mapped anywhere. +</p> +<p>The command should be modified as follows, +</p><div class="example"> +<pre class="example">ffmpeg -i A.avi -i B.mp4 -i C.mkv -filter_complex "[1:v]hue=s=0,split=2[outv1][outv2];overlay;aresample" \ + -map '[outv1]' -an out1.mp4 \ + out2.mkv \ + -map '[outv2]' -map 1:a:0 out3.mkv +</pre></div> +<p>The video stream from <samp>B.mp4</samp> is sent to the hue filter, whose output is cloned once using +the split filter, and both outputs labelled. Then a copy each is mapped to the first and third +output files. +</p> +<p>The overlay filter, requiring two video inputs, uses the first two unused video streams. Those +are the streams from <samp>A.avi</samp> and <samp>C.mkv</samp>. The overlay output isn’t labelled, so it is +sent to the first output file <samp>out1.mp4</samp>, regardless of the presence of the <code>-map</code> option. +</p> +<p>The aresample filter is sent the first unused audio stream, that of <samp>A.avi</samp>. Since this filter +output is also unlabelled, it too is mapped to the first output file. The presence of <code>-an</code> +only suppresses automatic or manual stream selection of audio streams, not outputs sent from +filtergraphs. Both these mapped streams shall be ordered before the mapped stream in <samp>out1.mp4</samp>. +</p> +<p>The video, audio and subtitle streams mapped to <code>out2.mkv</code> are entirely determined by +automatic stream selection. +</p> +<p><samp>out3.mkv</samp> consists of the cloned video output from the hue filter and the first audio +stream from <samp>B.mp4</samp>. +<br> +</p> + +<a name="Options"></a> +<h2 class="chapter">5 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options" aria-hidden="true">TOC</a></span></h2> + +<p>All the numerical options, if not specified otherwise, accept a string +representing a number as input, which may be followed by one of the SI +unit prefixes, for example: ’K’, ’M’, or ’G’. +</p> +<p>If ’i’ is appended to the SI unit prefix, the complete prefix will be +interpreted as a unit prefix for binary multiples, which are based on +powers of 1024 instead of powers of 1000. Appending ’B’ to the SI unit +prefix multiplies the value by 8. This allows using, for example: +’KB’, ’MiB’, ’G’ and ’B’ as number suffixes. +</p> +<p>Options which do not take arguments are boolean options, and set the +corresponding value to true. They can be set to false by prefixing +the option name with "no". For example using "-nofoo" +will set the boolean option with name "foo" to false. +</p> +<span id="Stream-specifiers"></span><a name="Stream-specifiers-1"></a> +<h3 class="section">5.1 Stream specifiers<span class="pull-right"><a class="anchor hidden-xs" href="#Stream-specifiers-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Stream-specifiers-1" aria-hidden="true">TOC</a></span></h3> +<p>Some options are applied per-stream, e.g. bitrate or codec. Stream specifiers +are used to precisely specify which stream(s) a given option belongs to. +</p> +<p>A stream specifier is a string generally appended to the option name and +separated from it by a colon. E.g. <code>-codec:a:1 ac3</code> contains the +<code>a:1</code> stream specifier, which matches the second audio stream. Therefore, it +would select the ac3 codec for the second audio stream. +</p> +<p>A stream specifier can match several streams, so that the option is applied to all +of them. E.g. the stream specifier in <code>-b:a 128k</code> matches all audio +streams. +</p> +<p>An empty stream specifier matches all streams. For example, <code>-codec copy</code> +or <code>-codec: copy</code> would copy all the streams without reencoding. +</p> +<p>Possible forms of stream specifiers are: +</p><dl compact="compact"> +<dt><span><samp><var>stream_index</var></samp></span></dt> +<dd><p>Matches the stream with this index. E.g. <code>-threads:1 4</code> would set the +thread count for the second stream to 4. If <var>stream_index</var> is used as an +additional stream specifier (see below), then it selects stream number +<var>stream_index</var> from the matching streams. Stream numbering is based on the +order of the streams as detected by libavformat except when a program ID is +also specified. In this case it is based on the ordering of the streams in the +program. +</p></dd> +<dt><span><samp><var>stream_type</var>[:<var>additional_stream_specifier</var>]</samp></span></dt> +<dd><p><var>stream_type</var> is one of following: ’v’ or ’V’ for video, ’a’ for audio, ’s’ +for subtitle, ’d’ for data, and ’t’ for attachments. ’v’ matches all video +streams, ’V’ only matches video streams which are not attached pictures, video +thumbnails or cover arts. If <var>additional_stream_specifier</var> is used, then +it matches streams which both have this type and match the +<var>additional_stream_specifier</var>. Otherwise, it matches all streams of the +specified type. +</p></dd> +<dt><span><samp>p:<var>program_id</var>[:<var>additional_stream_specifier</var>]</samp></span></dt> +<dd><p>Matches streams which are in the program with the id <var>program_id</var>. If +<var>additional_stream_specifier</var> is used, then it matches streams which both +are part of the program and match the <var>additional_stream_specifier</var>. +</p> +</dd> +<dt><span><samp>#<var>stream_id</var> or i:<var>stream_id</var></samp></span></dt> +<dd><p>Match the stream by stream id (e.g. PID in MPEG-TS container). +</p></dd> +<dt><span><samp>m:<var>key</var>[:<var>value</var>]</samp></span></dt> +<dd><p>Matches streams with the metadata tag <var>key</var> having the specified value. If +<var>value</var> is not given, matches streams that contain the given tag with any +value. +</p></dd> +<dt><span><samp>u</samp></span></dt> +<dd><p>Matches streams with usable configuration, the codec must be defined and the +essential information such as video dimension or audio sample rate must be present. +</p> +<p>Note that in <code>ffmpeg</code>, matching by metadata will only work properly for +input files. +</p></dd> +</dl> + +<a name="Generic-options"></a> +<h3 class="section">5.2 Generic options<span class="pull-right"><a class="anchor hidden-xs" href="#Generic-options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Generic-options" aria-hidden="true">TOC</a></span></h3> + +<p>These options are shared amongst the ff* tools. +</p> +<dl compact="compact"> +<dt><span><samp>-L</samp></span></dt> +<dd><p>Show license. +</p> +</dd> +<dt><span><samp>-h, -?, -help, --help [<var>arg</var>]</samp></span></dt> +<dd><p>Show help. An optional parameter may be specified to print help about a specific +item. If no argument is specified, only basic (non advanced) tool +options are shown. +</p> +<p>Possible values of <var>arg</var> are: +</p><dl compact="compact"> +<dt><span><samp>long</samp></span></dt> +<dd><p>Print advanced tool options in addition to the basic tool options. +</p> +</dd> +<dt><span><samp>full</samp></span></dt> +<dd><p>Print complete list of options, including shared and private options +for encoders, decoders, demuxers, muxers, filters, etc. +</p> +</dd> +<dt><span><samp>decoder=<var>decoder_name</var></samp></span></dt> +<dd><p>Print detailed information about the decoder named <var>decoder_name</var>. Use the +<samp>-decoders</samp> option to get a list of all decoders. +</p> +</dd> +<dt><span><samp>encoder=<var>encoder_name</var></samp></span></dt> +<dd><p>Print detailed information about the encoder named <var>encoder_name</var>. Use the +<samp>-encoders</samp> option to get a list of all encoders. +</p> +</dd> +<dt><span><samp>demuxer=<var>demuxer_name</var></samp></span></dt> +<dd><p>Print detailed information about the demuxer named <var>demuxer_name</var>. Use the +<samp>-formats</samp> option to get a list of all demuxers and muxers. +</p> +</dd> +<dt><span><samp>muxer=<var>muxer_name</var></samp></span></dt> +<dd><p>Print detailed information about the muxer named <var>muxer_name</var>. Use the +<samp>-formats</samp> option to get a list of all muxers and demuxers. +</p> +</dd> +<dt><span><samp>filter=<var>filter_name</var></samp></span></dt> +<dd><p>Print detailed information about the filter named <var>filter_name</var>. Use the +<samp>-filters</samp> option to get a list of all filters. +</p> +</dd> +<dt><span><samp>bsf=<var>bitstream_filter_name</var></samp></span></dt> +<dd><p>Print detailed information about the bitstream filter named <var>bitstream_filter_name</var>. +Use the <samp>-bsfs</samp> option to get a list of all bitstream filters. +</p> +</dd> +<dt><span><samp>protocol=<var>protocol_name</var></samp></span></dt> +<dd><p>Print detailed information about the protocol named <var>protocol_name</var>. +Use the <samp>-protocols</samp> option to get a list of all protocols. +</p></dd> +</dl> + +</dd> +<dt><span><samp>-version</samp></span></dt> +<dd><p>Show version. +</p> +</dd> +<dt><span><samp>-buildconf</samp></span></dt> +<dd><p>Show the build configuration, one option per line. +</p> +</dd> +<dt><span><samp>-formats</samp></span></dt> +<dd><p>Show available formats (including devices). +</p> +</dd> +<dt><span><samp>-demuxers</samp></span></dt> +<dd><p>Show available demuxers. +</p> +</dd> +<dt><span><samp>-muxers</samp></span></dt> +<dd><p>Show available muxers. +</p> +</dd> +<dt><span><samp>-devices</samp></span></dt> +<dd><p>Show available devices. +</p> +</dd> +<dt><span><samp>-codecs</samp></span></dt> +<dd><p>Show all codecs known to libavcodec. +</p> +<p>Note that the term ’codec’ is used throughout this documentation as a shortcut +for what is more correctly called a media bitstream format. +</p> +</dd> +<dt><span><samp>-decoders</samp></span></dt> +<dd><p>Show available decoders. +</p> +</dd> +<dt><span><samp>-encoders</samp></span></dt> +<dd><p>Show all available encoders. +</p> +</dd> +<dt><span><samp>-bsfs</samp></span></dt> +<dd><p>Show available bitstream filters. +</p> +</dd> +<dt><span><samp>-protocols</samp></span></dt> +<dd><p>Show available protocols. +</p> +</dd> +<dt><span><samp>-filters</samp></span></dt> +<dd><p>Show available libavfilter filters. +</p> +</dd> +<dt><span><samp>-pix_fmts</samp></span></dt> +<dd><p>Show available pixel formats. +</p> +</dd> +<dt><span><samp>-sample_fmts</samp></span></dt> +<dd><p>Show available sample formats. +</p> +</dd> +<dt><span><samp>-layouts</samp></span></dt> +<dd><p>Show channel names and standard channel layouts. +</p> +</dd> +<dt><span><samp>-dispositions</samp></span></dt> +<dd><p>Show stream dispositions. +</p> +</dd> +<dt><span><samp>-colors</samp></span></dt> +<dd><p>Show recognized color names. +</p> +</dd> +<dt><span><samp>-sources <var>device</var>[,<var>opt1</var>=<var>val1</var>[,<var>opt2</var>=<var>val2</var>]...]</samp></span></dt> +<dd><p>Show autodetected sources of the input device. +Some devices may provide system-dependent source names that cannot be autodetected. +The returned list cannot be assumed to be always complete. +</p><div class="example"> +<pre class="example">ffmpeg -sources pulse,server=192.168.0.4 +</pre></div> + +</dd> +<dt><span><samp>-sinks <var>device</var>[,<var>opt1</var>=<var>val1</var>[,<var>opt2</var>=<var>val2</var>]...]</samp></span></dt> +<dd><p>Show autodetected sinks of the output device. +Some devices may provide system-dependent sink names that cannot be autodetected. +The returned list cannot be assumed to be always complete. +</p><div class="example"> +<pre class="example">ffmpeg -sinks pulse,server=192.168.0.4 +</pre></div> + +</dd> +<dt><span><samp>-loglevel [<var>flags</var>+]<var>loglevel</var> | -v [<var>flags</var>+]<var>loglevel</var></samp></span></dt> +<dd><p>Set logging level and flags used by the library. +</p> +<p>The optional <var>flags</var> prefix can consist of the following values: +</p><dl compact="compact"> +<dt><span>‘<samp>repeat</samp>’</span></dt> +<dd><p>Indicates that repeated log output should not be compressed to the first line +and the "Last message repeated n times" line will be omitted. +</p></dd> +<dt><span>‘<samp>level</samp>’</span></dt> +<dd><p>Indicates that log output should add a <code>[level]</code> prefix to each message +line. This can be used as an alternative to log coloring, e.g. when dumping the +log to file. +</p></dd> +</dl> +<p>Flags can also be used alone by adding a ’+’/’-’ prefix to set/reset a single +flag without affecting other <var>flags</var> or changing <var>loglevel</var>. When +setting both <var>flags</var> and <var>loglevel</var>, a ’+’ separator is expected +between the last <var>flags</var> value and before <var>loglevel</var>. +</p> +<p><var>loglevel</var> is a string or a number containing one of the following values: +</p><dl compact="compact"> +<dt><span>‘<samp>quiet, -8</samp>’</span></dt> +<dd><p>Show nothing at all; be silent. +</p></dd> +<dt><span>‘<samp>panic, 0</samp>’</span></dt> +<dd><p>Only show fatal errors which could lead the process to crash, such as +an assertion failure. This is not currently used for anything. +</p></dd> +<dt><span>‘<samp>fatal, 8</samp>’</span></dt> +<dd><p>Only show fatal errors. These are errors after which the process absolutely +cannot continue. +</p></dd> +<dt><span>‘<samp>error, 16</samp>’</span></dt> +<dd><p>Show all errors, including ones which can be recovered from. +</p></dd> +<dt><span>‘<samp>warning, 24</samp>’</span></dt> +<dd><p>Show all warnings and errors. Any message related to possibly +incorrect or unexpected events will be shown. +</p></dd> +<dt><span>‘<samp>info, 32</samp>’</span></dt> +<dd><p>Show informative messages during processing. This is in addition to +warnings and errors. This is the default value. +</p></dd> +<dt><span>‘<samp>verbose, 40</samp>’</span></dt> +<dd><p>Same as <code>info</code>, except more verbose. +</p></dd> +<dt><span>‘<samp>debug, 48</samp>’</span></dt> +<dd><p>Show everything, including debugging information. +</p></dd> +<dt><span>‘<samp>trace, 56</samp>’</span></dt> +</dl> + +<p>For example to enable repeated log output, add the <code>level</code> prefix, and set +<var>loglevel</var> to <code>verbose</code>: +</p><div class="example"> +<pre class="example">ffmpeg -loglevel repeat+level+verbose -i input output +</pre></div> +<p>Another example that enables repeated log output without affecting current +state of <code>level</code> prefix flag or <var>loglevel</var>: +</p><div class="example"> +<pre class="example">ffmpeg [...] -loglevel +repeat +</pre></div> + +<p>By default the program logs to stderr. If coloring is supported by the +terminal, colors are used to mark errors and warnings. Log coloring +can be disabled setting the environment variable +<code>AV_LOG_FORCE_NOCOLOR</code>, or can be forced setting +the environment variable <code>AV_LOG_FORCE_COLOR</code>. +</p> +</dd> +<dt><span><samp>-report</samp></span></dt> +<dd><p>Dump full command line and log output to a file named +<code><var>program</var>-<var>YYYYMMDD</var>-<var>HHMMSS</var>.log</code> in the current +directory. +This file can be useful for bug reports. +It also implies <code>-loglevel debug</code>. +</p> +<p>Setting the environment variable <code>FFREPORT</code> to any value has the +same effect. If the value is a ’:’-separated key=value sequence, these +options will affect the report; option values must be escaped if they +contain special characters or the options delimiter ’:’ (see the +“Quoting and escaping” section in the ffmpeg-utils manual). +</p> +<p>The following options are recognized: +</p><dl compact="compact"> +<dt><span><samp>file</samp></span></dt> +<dd><p>set the file name to use for the report; <code>%p</code> is expanded to the name +of the program, <code>%t</code> is expanded to a timestamp, <code>%%</code> is expanded +to a plain <code>%</code> +</p></dd> +<dt><span><samp>level</samp></span></dt> +<dd><p>set the log verbosity level using a numerical value (see <code>-loglevel</code>). +</p></dd> +</dl> + +<p>For example, to output a report to a file named <samp>ffreport.log</samp> +using a log level of <code>32</code> (alias for log level <code>info</code>): +</p> +<div class="example"> +<pre class="example">FFREPORT=file=ffreport.log:level=32 ffmpeg -i input output +</pre></div> + +<p>Errors in parsing the environment variable are not fatal, and will not +appear in the report. +</p> +</dd> +<dt><span><samp>-hide_banner</samp></span></dt> +<dd><p>Suppress printing banner. +</p> +<p>All FFmpeg tools will normally show a copyright notice, build options +and library versions. This option can be used to suppress printing +this information. +</p> +</dd> +<dt><span><samp>-cpuflags flags (<em>global</em>)</samp></span></dt> +<dd><p>Allows setting and clearing cpu flags. This option is intended +for testing. Do not use it unless you know what you’re doing. +</p><div class="example"> +<pre class="example">ffmpeg -cpuflags -sse+mmx ... +ffmpeg -cpuflags mmx ... +ffmpeg -cpuflags 0 ... +</pre></div> +<p>Possible flags for this option are: +</p><dl compact="compact"> +<dt><span>‘<samp>x86</samp>’</span></dt> +<dd><dl compact="compact"> +<dt><span>‘<samp>mmx</samp>’</span></dt> +<dt><span>‘<samp>mmxext</samp>’</span></dt> +<dt><span>‘<samp>sse</samp>’</span></dt> +<dt><span>‘<samp>sse2</samp>’</span></dt> +<dt><span>‘<samp>sse2slow</samp>’</span></dt> +<dt><span>‘<samp>sse3</samp>’</span></dt> +<dt><span>‘<samp>sse3slow</samp>’</span></dt> +<dt><span>‘<samp>ssse3</samp>’</span></dt> +<dt><span>‘<samp>atom</samp>’</span></dt> +<dt><span>‘<samp>sse4.1</samp>’</span></dt> +<dt><span>‘<samp>sse4.2</samp>’</span></dt> +<dt><span>‘<samp>avx</samp>’</span></dt> +<dt><span>‘<samp>avx2</samp>’</span></dt> +<dt><span>‘<samp>xop</samp>’</span></dt> +<dt><span>‘<samp>fma3</samp>’</span></dt> +<dt><span>‘<samp>fma4</samp>’</span></dt> +<dt><span>‘<samp>3dnow</samp>’</span></dt> +<dt><span>‘<samp>3dnowext</samp>’</span></dt> +<dt><span>‘<samp>bmi1</samp>’</span></dt> +<dt><span>‘<samp>bmi2</samp>’</span></dt> +<dt><span>‘<samp>cmov</samp>’</span></dt> +</dl> +</dd> +<dt><span>‘<samp>ARM</samp>’</span></dt> +<dd><dl compact="compact"> +<dt><span>‘<samp>armv5te</samp>’</span></dt> +<dt><span>‘<samp>armv6</samp>’</span></dt> +<dt><span>‘<samp>armv6t2</samp>’</span></dt> +<dt><span>‘<samp>vfp</samp>’</span></dt> +<dt><span>‘<samp>vfpv3</samp>’</span></dt> +<dt><span>‘<samp>neon</samp>’</span></dt> +<dt><span>‘<samp>setend</samp>’</span></dt> +</dl> +</dd> +<dt><span>‘<samp>AArch64</samp>’</span></dt> +<dd><dl compact="compact"> +<dt><span>‘<samp>armv8</samp>’</span></dt> +<dt><span>‘<samp>vfp</samp>’</span></dt> +<dt><span>‘<samp>neon</samp>’</span></dt> +</dl> +</dd> +<dt><span>‘<samp>PowerPC</samp>’</span></dt> +<dd><dl compact="compact"> +<dt><span>‘<samp>altivec</samp>’</span></dt> +</dl> +</dd> +<dt><span>‘<samp>Specific Processors</samp>’</span></dt> +<dd><dl compact="compact"> +<dt><span>‘<samp>pentium2</samp>’</span></dt> +<dt><span>‘<samp>pentium3</samp>’</span></dt> +<dt><span>‘<samp>pentium4</samp>’</span></dt> +<dt><span>‘<samp>k6</samp>’</span></dt> +<dt><span>‘<samp>k62</samp>’</span></dt> +<dt><span>‘<samp>athlon</samp>’</span></dt> +<dt><span>‘<samp>athlonxp</samp>’</span></dt> +<dt><span>‘<samp>k8</samp>’</span></dt> +</dl> +</dd> +</dl> + +</dd> +<dt><span><samp>-cpucount <var>count</var> (<em>global</em>)</samp></span></dt> +<dd><p>Override detection of CPU count. This option is intended +for testing. Do not use it unless you know what you’re doing. +</p><div class="example"> +<pre class="example">ffmpeg -cpucount 2 +</pre></div> + +</dd> +<dt><span><samp>-max_alloc <var>bytes</var></samp></span></dt> +<dd><p>Set the maximum size limit for allocating a block on the heap by ffmpeg’s +family of malloc functions. Exercise <strong>extreme caution</strong> when using +this option. Don’t use if you do not understand the full consequence of doing so. +Default is INT_MAX. +</p></dd> +</dl> + +<a name="AVOptions"></a> +<h3 class="section">5.3 AVOptions<span class="pull-right"><a class="anchor hidden-xs" href="#AVOptions" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-AVOptions" aria-hidden="true">TOC</a></span></h3> + +<p>These options are provided directly by the libavformat, libavdevice and +libavcodec libraries. To see the list of available AVOptions, use the +<samp>-help</samp> option. They are separated into two categories: +</p><dl compact="compact"> +<dt><span><samp>generic</samp></span></dt> +<dd><p>These options can be set for any container, codec or device. Generic options +are listed under AVFormatContext options for containers/devices and under +AVCodecContext options for codecs. +</p></dd> +<dt><span><samp>private</samp></span></dt> +<dd><p>These options are specific to the given container, device or codec. Private +options are listed under their corresponding containers/devices/codecs. +</p></dd> +</dl> + +<p>For example to write an ID3v2.3 header instead of a default ID3v2.4 to +an MP3 file, use the <samp>id3v2_version</samp> private option of the MP3 +muxer: +</p><div class="example"> +<pre class="example">ffmpeg -i input.flac -id3v2_version 3 out.mp3 +</pre></div> + +<p>All codec AVOptions are per-stream, and thus a stream specifier +should be attached to them: +</p><div class="example"> +<pre class="example">ffmpeg -i multichannel.mxf -map 0:v:0 -map 0:a:0 -map 0:a:0 -c:a:0 ac3 -b:a:0 640k -ac:a:1 2 -c:a:1 aac -b:2 128k out.mp4 +</pre></div> + +<p>In the above example, a multichannel audio stream is mapped twice for output. +The first instance is encoded with codec ac3 and bitrate 640k. +The second instance is downmixed to 2 channels and encoded with codec aac. A bitrate of 128k is specified for it using +absolute index of the output stream. +</p> +<p>Note: the <samp>-nooption</samp> syntax cannot be used for boolean +AVOptions, use <samp>-option 0</samp>/<samp>-option 1</samp>. +</p> +<p>Note: the old undocumented way of specifying per-stream AVOptions by +prepending v/a/s to the options name is now obsolete and will be +removed soon. +</p> +<a name="Main-options"></a> +<h3 class="section">5.4 Main options<span class="pull-right"><a class="anchor hidden-xs" href="#Main-options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Main-options" aria-hidden="true">TOC</a></span></h3> + +<dl compact="compact"> +<dt><span><samp>-f <var>fmt</var> (<em>input/output</em>)</samp></span></dt> +<dd><p>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. +</p> +</dd> +<dt><span><samp>-i <var>url</var> (<em>input</em>)</samp></span></dt> +<dd><p>input file url +</p> +</dd> +<dt><span><samp>-y (<em>global</em>)</samp></span></dt> +<dd><p>Overwrite output files without asking. +</p> +</dd> +<dt><span><samp>-n (<em>global</em>)</samp></span></dt> +<dd><p>Do not overwrite output files, and exit immediately if a specified +output file already exists. +</p> +</dd> +<dt><span><samp>-stream_loop <var>number</var> (<em>input</em>)</samp></span></dt> +<dd><p>Set number of times input stream shall be looped. Loop 0 means no loop, +loop -1 means infinite loop. +</p> +</dd> +<dt><span><samp>-recast_media (<em>global</em>)</samp></span></dt> +<dd><p>Allow forcing a decoder of a different media type than the one +detected or designated by the demuxer. Useful for decoding media +data muxed as data streams. +</p> +</dd> +<dt><span><samp>-c[:<var>stream_specifier</var>] <var>codec</var> (<em>input/output,per-stream</em>)</samp></span></dt> +<dt><span><samp>-codec[:<var>stream_specifier</var>] <var>codec</var> (<em>input/output,per-stream</em>)</samp></span></dt> +<dd><p>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</var> is the name of a +decoder/encoder or a special value <code>copy</code> (output only) to indicate that +the stream is not to be re-encoded. +</p> +<p>For example +</p><div class="example"> +<pre class="example">ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT +</pre></div> +<p>encodes all video streams with libx264 and copies all audio streams. +</p> +<p>For each stream, the last matching <code>c</code> option is applied, so +</p><div class="example"> +<pre class="example">ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT +</pre></div> +<p>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. +</p> +</dd> +<dt><span><samp>-t <var>duration</var> (<em>input/output</em>)</samp></span></dt> +<dd><p>When used as an input option (before <code>-i</code>), limit the <var>duration</var> of +data read from the input file. +</p> +<p>When used as an output option (before an output url), stop writing the +output after its duration reaches <var>duration</var>. +</p> +<p><var>duration</var> must be a time duration specification, +see <a data-manual="ffmpeg-utils" href="ffmpeg-utils.html#time-duration-syntax">(ffmpeg-utils)the Time duration section in the ffmpeg-utils(1) manual</a>. +</p> +<p>-to and -t are mutually exclusive and -t has priority. +</p> +</dd> +<dt><span><samp>-to <var>position</var> (<em>input/output</em>)</samp></span></dt> +<dd><p>Stop writing the output or reading the input at <var>position</var>. +<var>position</var> must be a time duration specification, +see <a data-manual="ffmpeg-utils" href="ffmpeg-utils.html#time-duration-syntax">(ffmpeg-utils)the Time duration section in the ffmpeg-utils(1) manual</a>. +</p> +<p>-to and -t are mutually exclusive and -t has priority. +</p> +</dd> +<dt><span><samp>-fs <var>limit_size</var> (<em>output</em>)</samp></span></dt> +<dd><p>Set the file size limit, expressed in bytes. No further chunk of bytes is written +after the limit is exceeded. The size of the output file is slightly more than the +requested file size. +</p> +</dd> +<dt><span><samp>-ss <var>position</var> (<em>input/output</em>)</samp></span></dt> +<dd><p>When used as an input option (before <code>-i</code>), seeks in this input file to +<var>position</var>. Note that in most formats it is not possible to seek exactly, +so <code>ffmpeg</code> will seek to the closest seek point before <var>position</var>. +When transcoding and <samp>-accurate_seek</samp> is enabled (the default), this +extra segment between the seek point and <var>position</var> will be decoded and +discarded. When doing stream copy or when <samp>-noaccurate_seek</samp> is used, it +will be preserved. +</p> +<p>When used as an output option (before an output url), decodes but discards +input until the timestamps reach <var>position</var>. +</p> +<p><var>position</var> must be a time duration specification, +see <a data-manual="ffmpeg-utils" href="ffmpeg-utils.html#time-duration-syntax">(ffmpeg-utils)the Time duration section in the ffmpeg-utils(1) manual</a>. +</p> +</dd> +<dt><span><samp>-sseof <var>position</var> (<em>input</em>)</samp></span></dt> +<dd> +<p>Like the <code>-ss</code> option but relative to the "end of file". That is negative +values are earlier in the file, 0 is at EOF. +</p> +</dd> +<dt><span><samp>-isync <var>input_index</var> (<em>input</em>)</samp></span></dt> +<dd><p>Assign an input as a sync source. +</p> +<p>This will take the difference between the start times of the target and reference inputs and +offset the timestamps of the target file by that difference. The source timestamps of the two +inputs should derive from the same clock source for expected results. If <code>copyts</code> is set +then <code>start_at_zero</code> must also be set. If either of the inputs has no starting timestamp +then no sync adjustment is made. +</p> +<p>Acceptable values are those that refer to a valid ffmpeg input index. If the sync reference is +the target index itself or <var>-1</var>, then no adjustment is made to target timestamps. A sync +reference may not itself be synced to any other input. +</p> +<p>Default value is <var>-1</var>. +</p> +</dd> +<dt><span><samp>-itsoffset <var>offset</var> (<em>input</em>)</samp></span></dt> +<dd><p>Set the input time offset. +</p> +<p><var>offset</var> must be a time duration specification, +see <a data-manual="ffmpeg-utils" href="ffmpeg-utils.html#time-duration-syntax">(ffmpeg-utils)the Time duration section in the ffmpeg-utils(1) manual</a>. +</p> +<p>The offset is added to the timestamps of the input files. Specifying +a positive offset means that the corresponding streams are delayed by +the time duration specified in <var>offset</var>. +</p> +</dd> +<dt><span><samp>-itsscale <var>scale</var> (<em>input,per-stream</em>)</samp></span></dt> +<dd><p>Rescale input timestamps. <var>scale</var> should be a floating point number. +</p> +</dd> +<dt><span><samp>-timestamp <var>date</var> (<em>output</em>)</samp></span></dt> +<dd><p>Set the recording timestamp in the container. +</p> +<p><var>date</var> must be a date specification, +see <a data-manual="ffmpeg-utils" href="ffmpeg-utils.html#date-syntax">(ffmpeg-utils)the Date section in the ffmpeg-utils(1) manual</a>. +</p> +</dd> +<dt><span><samp>-metadata[:metadata_specifier] <var>key</var>=<var>value</var> (<em>output,per-metadata</em>)</samp></span></dt> +<dd><p>Set a metadata key/value pair. +</p> +<p>An optional <var>metadata_specifier</var> may be given to set metadata +on streams, chapters or programs. See <code>-map_metadata</code> +documentation for details. +</p> +<p>This option overrides metadata set with <code>-map_metadata</code>. It is +also possible to delete metadata by using an empty value. +</p> +<p>For example, for setting the title in the output file: +</p><div class="example"> +<pre class="example">ffmpeg -i in.avi -metadata title="my title" out.flv +</pre></div> + +<p>To set the language of the first audio stream: +</p><div class="example"> +<pre class="example">ffmpeg -i INPUT -metadata:s:a:0 language=eng OUTPUT +</pre></div> + +</dd> +<dt><span><samp>-disposition[:stream_specifier] <var>value</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>Sets the disposition for a stream. +</p> +<p>By default, the disposition is copied from the input stream, unless the output +stream this option applies to is fed by a complex filtergraph - in that case the +disposition is unset by default. +</p> +<p><var>value</var> is a sequence of items separated by ’+’ or ’-’. The first item may +also be prefixed with ’+’ or ’-’, in which case this option modifies the default +value. Otherwise (the first item is not prefixed) this options overrides the +default value. A ’+’ prefix adds the given disposition, ’-’ removes it. It is +also possible to clear the disposition by setting it to 0. +</p> +<p>If no <code>-disposition</code> options were specified for an output file, ffmpeg will +automatically set the ’default’ disposition on the first stream of each type, +when there are multiple streams of this type in the output file and no stream of +that type is already marked as default. +</p> +<p>The <code>-dispositions</code> option lists the known dispositions. +</p> +<p>For example, to make the second audio stream the default stream: +</p><div class="example"> +<pre class="example">ffmpeg -i in.mkv -c copy -disposition:a:1 default out.mkv +</pre></div> + +<p>To make the second subtitle stream the default stream and remove the default +disposition from the first subtitle stream: +</p><div class="example"> +<pre class="example">ffmpeg -i in.mkv -c copy -disposition:s:0 0 -disposition:s:1 default out.mkv +</pre></div> + +<p>To add an embedded cover/thumbnail: +</p><div class="example"> +<pre class="example">ffmpeg -i in.mp4 -i IMAGE -map 0 -map 1 -c copy -c:v:1 png -disposition:v:1 attached_pic out.mp4 +</pre></div> + +<p>Not all muxers support embedded thumbnails, and those who do, only support a few formats, like JPEG or PNG. +</p> +</dd> +<dt><span><samp>-program [title=<var>title</var>:][program_num=<var>program_num</var>:]st=<var>stream</var>[:st=<var>stream</var>...] (<em>output</em>)</samp></span></dt> +<dd> +<p>Creates a program with the specified <var>title</var>, <var>program_num</var> and adds the specified +<var>stream</var>(s) to it. +</p> +</dd> +<dt><span><samp>-target <var>type</var> (<em>output</em>)</samp></span></dt> +<dd><p>Specify target file type (<code>vcd</code>, <code>svcd</code>, <code>dvd</code>, <code>dv</code>, +<code>dv50</code>). <var>type</var> may be prefixed with <code>pal-</code>, <code>ntsc-</code> or +<code>film-</code> to use the corresponding standard. All the format options +(bitrate, codecs, buffer sizes) are then set automatically. You can just type: +</p> +<div class="example"> +<pre class="example">ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg +</pre></div> + +<p>Nevertheless you can specify additional options as long as you know +they do not conflict with the standard, as in: +</p> +<div class="example"> +<pre class="example">ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg +</pre></div> + +<p>The parameters set for each target are as follows. +</p> +<p><strong>VCD</strong> +</p><div class="example"> +<pre class="example"><var>pal</var>: +-f vcd -muxrate 1411200 -muxpreload 0.44 -packetsize 2324 +-s 352x288 -r 25 +-codec:v mpeg1video -g 15 -b:v 1150k -maxrate:v 1150k -minrate:v 1150k -bufsize:v 327680 +-ar 44100 -ac 2 +-codec:a mp2 -b:a 224k + +<var>ntsc</var>: +-f vcd -muxrate 1411200 -muxpreload 0.44 -packetsize 2324 +-s 352x240 -r 30000/1001 +-codec:v mpeg1video -g 18 -b:v 1150k -maxrate:v 1150k -minrate:v 1150k -bufsize:v 327680 +-ar 44100 -ac 2 +-codec:a mp2 -b:a 224k + +<var>film</var>: +-f vcd -muxrate 1411200 -muxpreload 0.44 -packetsize 2324 +-s 352x240 -r 24000/1001 +-codec:v mpeg1video -g 18 -b:v 1150k -maxrate:v 1150k -minrate:v 1150k -bufsize:v 327680 +-ar 44100 -ac 2 +-codec:a mp2 -b:a 224k +</pre></div> + +<p><strong>SVCD</strong> +</p><div class="example"> +<pre class="example"><var>pal</var>: +-f svcd -packetsize 2324 +-s 480x576 -pix_fmt yuv420p -r 25 +-codec:v mpeg2video -g 15 -b:v 2040k -maxrate:v 2516k -minrate:v 0 -bufsize:v 1835008 -scan_offset 1 +-ar 44100 +-codec:a mp2 -b:a 224k + +<var>ntsc</var>: +-f svcd -packetsize 2324 +-s 480x480 -pix_fmt yuv420p -r 30000/1001 +-codec:v mpeg2video -g 18 -b:v 2040k -maxrate:v 2516k -minrate:v 0 -bufsize:v 1835008 -scan_offset 1 +-ar 44100 +-codec:a mp2 -b:a 224k + +<var>film</var>: +-f svcd -packetsize 2324 +-s 480x480 -pix_fmt yuv420p -r 24000/1001 +-codec:v mpeg2video -g 18 -b:v 2040k -maxrate:v 2516k -minrate:v 0 -bufsize:v 1835008 -scan_offset 1 +-ar 44100 +-codec:a mp2 -b:a 224k +</pre></div> + +<p><strong>DVD</strong> +</p><div class="example"> +<pre class="example"><var>pal</var>: +-f dvd -muxrate 10080k -packetsize 2048 +-s 720x576 -pix_fmt yuv420p -r 25 +-codec:v mpeg2video -g 15 -b:v 6000k -maxrate:v 9000k -minrate:v 0 -bufsize:v 1835008 +-ar 48000 +-codec:a ac3 -b:a 448k + +<var>ntsc</var>: +-f dvd -muxrate 10080k -packetsize 2048 +-s 720x480 -pix_fmt yuv420p -r 30000/1001 +-codec:v mpeg2video -g 18 -b:v 6000k -maxrate:v 9000k -minrate:v 0 -bufsize:v 1835008 +-ar 48000 +-codec:a ac3 -b:a 448k + +<var>film</var>: +-f dvd -muxrate 10080k -packetsize 2048 +-s 720x480 -pix_fmt yuv420p -r 24000/1001 +-codec:v mpeg2video -g 18 -b:v 6000k -maxrate:v 9000k -minrate:v 0 -bufsize:v 1835008 +-ar 48000 +-codec:a ac3 -b:a 448k +</pre></div> + +<p><strong>DV</strong> +</p><div class="example"> +<pre class="example"><var>pal</var>: +-f dv +-s 720x576 -pix_fmt yuv420p -r 25 +-ar 48000 -ac 2 + +<var>ntsc</var>: +-f dv +-s 720x480 -pix_fmt yuv411p -r 30000/1001 +-ar 48000 -ac 2 + +<var>film</var>: +-f dv +-s 720x480 -pix_fmt yuv411p -r 24000/1001 +-ar 48000 -ac 2 +</pre></div> +<p>The <code>dv50</code> target is identical to the <code>dv</code> target except that the pixel format set is <code>yuv422p</code> for all three standards. +</p> +<p>Any user-set value for a parameter above will override the target preset value. In that case, the output may +not comply with the target standard. +</p> +</dd> +<dt><span><samp>-dn (<em>input/output</em>)</samp></span></dt> +<dd><p>As an input option, blocks all data streams of a file from being filtered or +being automatically selected or mapped for any output. See <code>-discard</code> +option to disable streams individually. +</p> +<p>As an output option, disables data recording i.e. automatic selection or +mapping of any data stream. For full manual control see the <code>-map</code> +option. +</p> +</dd> +<dt><span><samp>-dframes <var>number</var> (<em>output</em>)</samp></span></dt> +<dd><p>Set the number of data frames to output. This is an obsolete alias for +<code>-frames:d</code>, which you should use instead. +</p> +</dd> +<dt><span><samp>-frames[:<var>stream_specifier</var>] <var>framecount</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>Stop writing to the stream after <var>framecount</var> frames. +</p> +</dd> +<dt><span><samp>-q[:<var>stream_specifier</var>] <var>q</var> (<em>output,per-stream</em>)</samp></span></dt> +<dt><span><samp>-qscale[:<var>stream_specifier</var>] <var>q</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>Use fixed quality scale (VBR). The meaning of <var>q</var>/<var>qscale</var> is +codec-dependent. +If <var>qscale</var> is used without a <var>stream_specifier</var> 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. +</p> +<span id="filter_005foption"></span></dd> +<dt><span><samp>-filter[:<var>stream_specifier</var>] <var>filtergraph</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>Create the filtergraph specified by <var>filtergraph</var> and use it to +filter the stream. +</p> +<p><var>filtergraph</var> 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</code>, and the output to the label <code>out</code>. See +the ffmpeg-filters manual for more information about the filtergraph +syntax. +</p> +<p>See the <a href="#filter_005fcomplex_005foption">-filter_complex option</a> if you +want to create filtergraphs with multiple inputs and/or outputs. +</p> +</dd> +<dt><span><samp>-filter_script[:<var>stream_specifier</var>] <var>filename</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>This option is similar to <samp>-filter</samp>, the only difference is that its +argument is the name of the file from which a filtergraph description is to be +read. +</p> +</dd> +<dt><span><samp>-reinit_filter[:<var>stream_specifier</var>] <var>integer</var> (<em>input,per-stream</em>)</samp></span></dt> +<dd><p>This boolean option determines if the filtergraph(s) to which this stream is fed gets +reinitialized when input frame parameters change mid-stream. This option is enabled by +default as most video and all audio filters cannot handle deviation in input frame properties. +Upon reinitialization, existing filter state is lost, like e.g. the frame count <code>n</code> +reference available in some filters. Any frames buffered at time of reinitialization are lost. +The properties where a change triggers reinitialization are, +for video, frame resolution or pixel format; +for audio, sample format, sample rate, channel count or channel layout. +</p> +</dd> +<dt><span><samp>-filter_threads <var>nb_threads</var> (<em>global</em>)</samp></span></dt> +<dd><p>Defines how many threads are used to process a filter pipeline. Each pipeline +will produce a thread pool with this many threads available for parallel processing. +The default is the number of available CPUs. +</p> +</dd> +<dt><span><samp>-pre[:<var>stream_specifier</var>] <var>preset_name</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>Specify the preset for matching stream(s). +</p> +</dd> +<dt><span><samp>-stats (<em>global</em>)</samp></span></dt> +<dd><p>Print encoding progress/statistics. It is on by default, to explicitly +disable it you need to specify <code>-nostats</code>. +</p> +</dd> +<dt><span><samp>-stats_period <var>time</var> (<em>global</em>)</samp></span></dt> +<dd><p>Set period at which encoding progress/statistics are updated. Default is 0.5 seconds. +</p> +</dd> +<dt><span><samp>-progress <var>url</var> (<em>global</em>)</samp></span></dt> +<dd><p>Send program-friendly progress information to <var>url</var>. +</p> +<p>Progress information is written periodically and at the end of +the encoding process. It is made of "<var>key</var>=<var>value</var>" lines. <var>key</var> +consists of only alphanumeric characters. The last key of a sequence of +progress information is always "progress". +</p> +<p>The update period is set using <code>-stats_period</code>. +</p> +<span id="stdin-option"></span></dd> +<dt><span><samp>-stdin</samp></span></dt> +<dd><p>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</code>. +</p> +<p>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</code> but it requires a +shell. +</p> +</dd> +<dt><span><samp>-debug_ts (<em>global</em>)</samp></span></dt> +<dd><p>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. +</p> +<p>See also the option <code>-fdebug ts</code>. +</p> +</dd> +<dt><span><samp>-attach <var>filename</var> (<em>output</em>)</samp></span></dt> +<dd><p>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</code> or automatic mappings). +</p> +<p>Note that for Matroska you also have to set the mimetype metadata tag: +</p><div class="example"> +<pre class="example">ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv +</pre></div> +<p>(assuming that the attachment stream will be third in the output file). +</p> +</dd> +<dt><span><samp>-dump_attachment[:<var>stream_specifier</var>] <var>filename</var> (<em>input,per-stream</em>)</samp></span></dt> +<dd><p>Extract the matching attachment stream into a file named <var>filename</var>. If +<var>filename</var> is empty, then the value of the <code>filename</code> metadata tag +will be used. +</p> +<p>E.g. to extract the first attachment to a file named ’out.ttf’: +</p><div class="example"> +<pre class="example">ffmpeg -dump_attachment:t:0 out.ttf -i INPUT +</pre></div> +<p>To extract all attachments to files determined by the <code>filename</code> tag: +</p><div class="example"> +<pre class="example">ffmpeg -dump_attachment:t "" -i INPUT +</pre></div> + +<p>Technical note – attachments are implemented as codec extradata, so this +option can actually be used to extract extradata from any stream, not just +attachments. +</p></dd> +</dl> + +<a name="Video-Options"></a> +<h3 class="section">5.5 Video Options<span class="pull-right"><a class="anchor hidden-xs" href="#Video-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Video-Options" aria-hidden="true">TOC</a></span></h3> + +<dl compact="compact"> +<dt><span><samp>-vframes <var>number</var> (<em>output</em>)</samp></span></dt> +<dd><p>Set the number of video frames to output. This is an obsolete alias for +<code>-frames:v</code>, which you should use instead. +</p></dd> +<dt><span><samp>-r[:<var>stream_specifier</var>] <var>fps</var> (<em>input/output,per-stream</em>)</samp></span></dt> +<dd><p>Set frame rate (Hz value, fraction or abbreviation). +</p> +<p>As an input option, ignore any timestamps stored in the file and instead +generate timestamps assuming constant frame rate <var>fps</var>. +This is not the same as the <samp>-framerate</samp> option used for some input formats +like image2 or v4l2 (it used to be the same in older versions of FFmpeg). +If in doubt use <samp>-framerate</samp> instead of the input option <samp>-r</samp>. +</p> +<p>As an output option, duplicate or drop input frames to achieve constant output +frame rate <var>fps</var>. +</p> +</dd> +<dt><span><samp>-fpsmax[:<var>stream_specifier</var>] <var>fps</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>Set maximum frame rate (Hz value, fraction or abbreviation). +</p> +<p>Clamps output frame rate when output framerate is auto-set and is higher than this value. +Useful in batch processing or when input framerate is wrongly detected as very high. +It cannot be set together with <code>-r</code>. It is ignored during streamcopy. +</p> +</dd> +<dt><span><samp>-s[:<var>stream_specifier</var>] <var>size</var> (<em>input/output,per-stream</em>)</samp></span></dt> +<dd><p>Set frame size. +</p> +<p>As an input option, this is a shortcut for the <samp>video_size</samp> 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. +</p> +<p>As an output option, this inserts the <code>scale</code> video filter to the +<em>end</em> of the corresponding filtergraph. Please use the <code>scale</code> filter +directly to insert it at the beginning or some other place. +</p> +<p>The format is ‘<samp>wxh</samp>’ (default - same as source). +</p> +</dd> +<dt><span><samp>-aspect[:<var>stream_specifier</var>] <var>aspect</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>Set the video display aspect ratio specified by <var>aspect</var>. +</p> +<p><var>aspect</var> can be a floating point number string, or a string of the +form <var>num</var>:<var>den</var>, where <var>num</var> and <var>den</var> are the +numerator and denominator of the aspect ratio. For example "4:3", +"16:9", "1.3333", and "1.7777" are valid argument values. +</p> +<p>If used together with <samp>-vcodec copy</samp>, it will affect the aspect ratio +stored at container level, but not the aspect ratio stored in encoded +frames, if it exists. +</p> +</dd> +<dt><span><samp>-display_rotation[:<var>stream_specifier</var>] <var>rotation</var> (<em>input,per-stream</em>)</samp></span></dt> +<dd><p>Set video rotation metadata. +</p> +<p><var>rotation</var> is a decimal number specifying the amount in degree by +which the video should be rotated counter-clockwise before being +displayed. +</p> +<p>This option overrides the rotation/display transform metadata stored in +the file, if any. When the video is being transcoded (rather than +copied) and <code>-autorotate</code> is enabled, the video will be rotated at +the filtering stage. Otherwise, the metadata will be written into the +output file if the muxer supports it. +</p> +<p>If the <code>-display_hflip</code> and/or <code>-display_vflip</code> options are +given, they are applied after the rotation specified by this option. +</p> +</dd> +<dt><span><samp>-display_hflip[:<var>stream_specifier</var>] (<em>input,per-stream</em>)</samp></span></dt> +<dd><p>Set whether on display the image should be horizontally flipped. +</p> +<p>See the <code>-display_rotation</code> option for more details. +</p> +</dd> +<dt><span><samp>-display_vflip[:<var>stream_specifier</var>] (<em>input,per-stream</em>)</samp></span></dt> +<dd><p>Set whether on display the image should be vertically flipped. +</p> +<p>See the <code>-display_rotation</code> option for more details. +</p> +</dd> +<dt><span><samp>-vn (<em>input/output</em>)</samp></span></dt> +<dd><p>As an input option, blocks all video streams of a file from being filtered or +being automatically selected or mapped for any output. See <code>-discard</code> +option to disable streams individually. +</p> +<p>As an output option, disables video recording i.e. automatic selection or +mapping of any video stream. For full manual control see the <code>-map</code> +option. +</p> +</dd> +<dt><span><samp>-vcodec <var>codec</var> (<em>output</em>)</samp></span></dt> +<dd><p>Set the video codec. This is an alias for <code>-codec:v</code>. +</p> +</dd> +<dt><span><samp>-pass[:<var>stream_specifier</var>] <var>n</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>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: +</p><div class="example"> +<pre class="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 +</pre></div> + +</dd> +<dt><span><samp>-passlogfile[:<var>stream_specifier</var>] <var>prefix</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>Set two-pass log file name prefix to <var>prefix</var>, the default file name +prefix is “ffmpeg2pass”. The complete file name will be +<samp>PREFIX-N.log</samp>, where N is a number specific to the output +stream +</p> +</dd> +<dt><span><samp>-vf <var>filtergraph</var> (<em>output</em>)</samp></span></dt> +<dd><p>Create the filtergraph specified by <var>filtergraph</var> and use it to +filter the stream. +</p> +<p>This is an alias for <code>-filter:v</code>, see the <a href="#filter_005foption">-filter option</a>. +</p> +</dd> +<dt><span><samp>-autorotate</samp></span></dt> +<dd><p>Automatically rotate the video according to file metadata. Enabled by +default, use <samp>-noautorotate</samp> to disable it. +</p> +</dd> +<dt><span><samp>-autoscale</samp></span></dt> +<dd><p>Automatically scale the video according to the resolution of first frame. +Enabled by default, use <samp>-noautoscale</samp> to disable it. When autoscale is +disabled, all output frames of filter graph might not be in the same resolution +and may be inadequate for some encoder/muxer. Therefore, it is not recommended +to disable it unless you really know what you are doing. +Disable autoscale at your own risk. +</p></dd> +</dl> + +<a name="Advanced-Video-options"></a> +<h3 class="section">5.6 Advanced Video options<span class="pull-right"><a class="anchor hidden-xs" href="#Advanced-Video-options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Advanced-Video-options" aria-hidden="true">TOC</a></span></h3> + +<dl compact="compact"> +<dt><span><samp>-pix_fmt[:<var>stream_specifier</var>] <var>format</var> (<em>input/output,per-stream</em>)</samp></span></dt> +<dd><p>Set pixel format. Use <code>-pix_fmts</code> 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</var> is prefixed by a <code>+</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</var> is a single <code>+</code>, ffmpeg selects the same pixel format +as the input (or graph output) and automatic conversions are disabled. +</p> +</dd> +<dt><span><samp>-sws_flags <var>flags</var> (<em>input/output</em>)</samp></span></dt> +<dd><p>Set SwScaler flags. +</p> +</dd> +<dt><span><samp>-rc_override[:<var>stream_specifier</var>] <var>override</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>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. +</p> +</dd> +<dt><span><samp>-ilme</samp></span></dt> +<dd><p>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 by use of a filter +such as <code>yadif</code> or <code>bwdif</code>, but deinterlacing introduces losses. +</p></dd> +<dt><span><samp>-psnr</samp></span></dt> +<dd><p>Calculate PSNR of compressed frames. This option is deprecated, pass the +PSNR flag to the encoder instead, using <code>-flags +psnr</code>. +</p></dd> +<dt><span><samp>-vstats</samp></span></dt> +<dd><p>Dump video coding statistics to <samp>vstats_HHMMSS.log</samp>. +</p></dd> +<dt><span><samp>-vstats_file <var>file</var></samp></span></dt> +<dd><p>Dump video coding statistics to <var>file</var>. +</p></dd> +<dt><span><samp>-vstats_version <var>file</var></samp></span></dt> +<dd><p>Specifies which version of the vstats format to use. Default is 2. +</p> +<p>version = 1 : +</p> +<p><code>frame= %5d q= %2.1f PSNR= %6.2f f_size= %6d s_size= %8.0fkB time= %0.3f br= %7.1fkbits/s avg_br= %7.1fkbits/s</code> +</p> +<p>version > 1: +</p> +<p><code>out= %2d st= %2d frame= %5d q= %2.1f PSNR= %6.2f f_size= %6d s_size= %8.0fkB time= %0.3f br= %7.1fkbits/s avg_br= %7.1fkbits/s</code> +</p></dd> +<dt><span><samp>-top[:<var>stream_specifier</var>] <var>n</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>top=1/bottom=0/auto=-1 field first +</p></dd> +<dt><span><samp>-dc <var>precision</var></samp></span></dt> +<dd><p>Intra_dc_precision. +</p></dd> +<dt><span><samp>-vtag <var>fourcc/tag</var> (<em>output</em>)</samp></span></dt> +<dd><p>Force video tag/fourcc. This is an alias for <code>-tag:v</code>. +</p></dd> +<dt><span><samp>-qphist (<em>global</em>)</samp></span></dt> +<dd><p>Show QP histogram +</p></dd> +<dt><span><samp>-vbsf <var>bitstream_filter</var></samp></span></dt> +<dd><p>Deprecated see -bsf +</p> +</dd> +<dt><span><samp>-force_key_frames[:<var>stream_specifier</var>] <var>time</var>[,<var>time</var>...] (<em>output,per-stream</em>)</samp></span></dt> +<dt><span><samp>-force_key_frames[:<var>stream_specifier</var>] expr:<var>expr</var> (<em>output,per-stream</em>)</samp></span></dt> +<dt><span><samp>-force_key_frames[:<var>stream_specifier</var>] source (<em>output,per-stream</em>)</samp></span></dt> +<dt><span><samp>-force_key_frames[:<var>stream_specifier</var>] source_no_drop (<em>output,per-stream</em>)</samp></span></dt> +<dd> +<p><var>force_key_frames</var> can take arguments of the following form: +</p> +<dl compact="compact"> +<dt><span><samp><var>time</var>[,<var>time</var>...]</samp></span></dt> +<dd><p>If the argument consists of timestamps, ffmpeg will round the specified times to the nearest +output timestamp as per the encoder time base and force a keyframe at the first frame having +timestamp equal or greater than the computed timestamp. Note that if the encoder time base is too +coarse, then the keyframes may be forced on frames with timestamps lower than the specified time. +The default encoder time base is the inverse of the output framerate but may be set otherwise +via <code>-enc_time_base</code>. +</p> +<p>If one of the times is "<code>chapters</code>[<var>delta</var>]", it is expanded into +the time of the beginning of all chapters in the file, shifted by +<var>delta</var>, 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. +</p> +<p>For example, to insert a key frame at 5 minutes, plus key frames 0.1 second +before the beginning of every chapter: +</p><div class="example"> +<pre class="example">-force_key_frames 0:05:00,chapters-0.1 +</pre></div> + +</dd> +<dt><span><samp>expr:<var>expr</var></samp></span></dt> +<dd><p>If the argument is prefixed with <code>expr:</code>, the string <var>expr</var> +is interpreted like an expression and is evaluated for each frame. A +key frame is forced in case the evaluation is non-zero. +</p> +<p>The expression in <var>expr</var> can contain the following constants: +</p><dl compact="compact"> +<dt><span><samp>n</samp></span></dt> +<dd><p>the number of current processed frame, starting from 0 +</p></dd> +<dt><span><samp>n_forced</samp></span></dt> +<dd><p>the number of forced frames +</p></dd> +<dt><span><samp>prev_forced_n</samp></span></dt> +<dd><p>the number of the previous forced frame, it is <code>NAN</code> when no +keyframe was forced yet +</p></dd> +<dt><span><samp>prev_forced_t</samp></span></dt> +<dd><p>the time of the previous forced frame, it is <code>NAN</code> when no +keyframe was forced yet +</p></dd> +<dt><span><samp>t</samp></span></dt> +<dd><p>the time of the current processed frame +</p></dd> +</dl> + +<p>For example to force a key frame every 5 seconds, you can specify: +</p><div class="example"> +<pre class="example">-force_key_frames expr:gte(t,n_forced*5) +</pre></div> + +<p>To force a key frame 5 seconds after the time of the last forced one, +starting from second 13: +</p><div class="example"> +<pre class="example">-force_key_frames expr:if(isnan(prev_forced_t),gte(t,13),gte(t,prev_forced_t+5)) +</pre></div> + +</dd> +<dt><span><samp>source</samp></span></dt> +<dd><p>If the argument is <code>source</code>, ffmpeg will force a key frame if +the current frame being encoded is marked as a key frame in its source. +</p> +</dd> +<dt><span><samp>source_no_drop</samp></span></dt> +<dd><p>If the argument is <code>source_no_drop</code>, ffmpeg will force a key frame if +the current frame being encoded is marked as a key frame in its source. +In cases where this particular source frame has to be dropped, +enforce the next available frame to become a key frame instead. +</p> +</dd> +</dl> + +<p>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. +</p> +</dd> +<dt><span><samp>-copyinkf[:<var>stream_specifier</var>] (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>When doing stream copy, copy also non-key frames found at the +beginning. +</p> +</dd> +<dt><span><samp>-init_hw_device <var>type</var>[=<var>name</var>][:<var>device</var>[,<var>key=value</var>...]]</samp></span></dt> +<dd><p>Initialise a new hardware device of type <var>type</var> called <var>name</var>, using the +given device parameters. +If no name is specified it will receive a default name of the form "<var>type</var>%d". +</p> +<p>The meaning of <var>device</var> and the following arguments depends on the +device type: +</p><dl compact="compact"> +<dt><span><samp>cuda</samp></span></dt> +<dd><p><var>device</var> is the number of the CUDA device. +</p> +<p>The following options are recognized: +</p><dl compact="compact"> +<dt><span><samp>primary_ctx</samp></span></dt> +<dd><p>If set to 1, uses the primary device context instead of creating a new one. +</p></dd> +</dl> + +<p>Examples: +</p><dl compact="compact"> +<dt><span><em>-init_hw_device cuda:1</em></span></dt> +<dd><p>Choose the second device on the system. +</p> +</dd> +<dt><span><em>-init_hw_device cuda:0,primary_ctx=1</em></span></dt> +<dd><p>Choose the first device and use the primary device context. +</p></dd> +</dl> + +</dd> +<dt><span><samp>dxva2</samp></span></dt> +<dd><p><var>device</var> is the number of the Direct3D 9 display adapter. +</p> +</dd> +<dt><span><samp>d3d11va</samp></span></dt> +<dd><p><var>device</var> is the number of the Direct3D 11 display adapter. +</p> +</dd> +<dt><span><samp>vaapi</samp></span></dt> +<dd><p><var>device</var> is either an X11 display name or a DRM render node. +If not specified, it will attempt to open the default X11 display (<em>$DISPLAY</em>) +and then the first DRM render node (<em>/dev/dri/renderD128</em>). +</p> +</dd> +<dt><span><samp>vdpau</samp></span></dt> +<dd><p><var>device</var> is an X11 display name. +If not specified, it will attempt to open the default X11 display (<em>$DISPLAY</em>). +</p> +</dd> +<dt><span><samp>qsv</samp></span></dt> +<dd><p><var>device</var> selects a value in ‘<samp>MFX_IMPL_*</samp>’. Allowed values are: +</p><dl compact="compact"> +<dt><span><samp>auto</samp></span></dt> +<dt><span><samp>sw</samp></span></dt> +<dt><span><samp>hw</samp></span></dt> +<dt><span><samp>auto_any</samp></span></dt> +<dt><span><samp>hw_any</samp></span></dt> +<dt><span><samp>hw2</samp></span></dt> +<dt><span><samp>hw3</samp></span></dt> +<dt><span><samp>hw4</samp></span></dt> +</dl> +<p>If not specified, ‘<samp>auto_any</samp>’ is used. +(Note that it may be easier to achieve the desired result for QSV by creating the +platform-appropriate subdevice (‘<samp>dxva2</samp>’ or ‘<samp>d3d11va</samp>’ or ‘<samp>vaapi</samp>’) and then deriving a +QSV device from that.) +</p> +<p>Alternatively, ‘<samp>child_device_type</samp>’ helps to choose platform-appropriate subdevice type. +On Windows ‘<samp>d3d11va</samp>’ is used as default subdevice type. +</p> +<p>Examples: +</p><dl compact="compact"> +<dt><span><em>-init_hw_device qsv:hw,child_device_type=d3d11va</em></span></dt> +<dd><p>Choose the GPU subdevice with type ‘<samp>d3d11va</samp>’ and create QSV device with ‘<samp>MFX_IMPL_HARDWARE</samp>’. +</p> +</dd> +<dt><span><em>-init_hw_device qsv:hw,child_device_type=dxva2</em></span></dt> +<dd><p>Choose the GPU subdevice with type ‘<samp>dxva2</samp>’ and create QSV device with ‘<samp>MFX_IMPL_HARDWARE</samp>’. +</p></dd> +</dl> + +</dd> +<dt><span><samp>opencl</samp></span></dt> +<dd><p><var>device</var> selects the platform and device as <em>platform_index.device_index</em>. +</p> +<p>The set of devices can also be filtered using the key-value pairs to find only +devices matching particular platform or device strings. +</p> +<p>The strings usable as filters are: +</p><dl compact="compact"> +<dt><span><samp>platform_profile</samp></span></dt> +<dt><span><samp>platform_version</samp></span></dt> +<dt><span><samp>platform_name</samp></span></dt> +<dt><span><samp>platform_vendor</samp></span></dt> +<dt><span><samp>platform_extensions</samp></span></dt> +<dt><span><samp>device_name</samp></span></dt> +<dt><span><samp>device_vendor</samp></span></dt> +<dt><span><samp>driver_version</samp></span></dt> +<dt><span><samp>device_version</samp></span></dt> +<dt><span><samp>device_profile</samp></span></dt> +<dt><span><samp>device_extensions</samp></span></dt> +<dt><span><samp>device_type</samp></span></dt> +</dl> + +<p>The indices and filters must together uniquely select a device. +</p> +<p>Examples: +</p><dl compact="compact"> +<dt><span><em>-init_hw_device opencl:0.1</em></span></dt> +<dd><p>Choose the second device on the first platform. +</p> +</dd> +<dt><span><em>-init_hw_device opencl:,device_name=Foo9000</em></span></dt> +<dd><p>Choose the device with a name containing the string <em>Foo9000</em>. +</p> +</dd> +<dt><span><em>-init_hw_device opencl:1,device_type=gpu,device_extensions=cl_khr_fp16</em></span></dt> +<dd><p>Choose the GPU device on the second platform supporting the <em>cl_khr_fp16</em> +extension. +</p></dd> +</dl> + +</dd> +<dt><span><samp>vulkan</samp></span></dt> +<dd><p>If <var>device</var> is an integer, it selects the device by its index in a +system-dependent list of devices. If <var>device</var> is any other string, it +selects the first device with a name containing that string as a substring. +</p> +<p>The following options are recognized: +</p><dl compact="compact"> +<dt><span><samp>debug</samp></span></dt> +<dd><p>If set to 1, enables the validation layer, if installed. +</p></dd> +<dt><span><samp>linear_images</samp></span></dt> +<dd><p>If set to 1, images allocated by the hwcontext will be linear and locally mappable. +</p></dd> +<dt><span><samp>instance_extensions</samp></span></dt> +<dd><p>A plus separated list of additional instance extensions to enable. +</p></dd> +<dt><span><samp>device_extensions</samp></span></dt> +<dd><p>A plus separated list of additional device extensions to enable. +</p></dd> +</dl> + +<p>Examples: +</p><dl compact="compact"> +<dt><span><em>-init_hw_device vulkan:1</em></span></dt> +<dd><p>Choose the second device on the system. +</p> +</dd> +<dt><span><em>-init_hw_device vulkan:RADV</em></span></dt> +<dd><p>Choose the first device with a name containing the string <em>RADV</em>. +</p> +</dd> +<dt><span><em>-init_hw_device vulkan:0,instance_extensions=VK_KHR_wayland_surface+VK_KHR_xcb_surface</em></span></dt> +<dd><p>Choose the first device and enable the Wayland and XCB instance extensions. +</p></dd> +</dl> + +</dd> +</dl> + +</dd> +<dt><span><samp>-init_hw_device <var>type</var>[=<var>name</var>]@<var>source</var></samp></span></dt> +<dd><p>Initialise a new hardware device of type <var>type</var> called <var>name</var>, +deriving it from the existing device with the name <var>source</var>. +</p> +</dd> +<dt><span><samp>-init_hw_device list</samp></span></dt> +<dd><p>List all hardware device types supported in this build of ffmpeg. +</p> +</dd> +<dt><span><samp>-filter_hw_device <var>name</var></samp></span></dt> +<dd><p>Pass the hardware device called <var>name</var> to all filters in any filter graph. +This can be used to set the device to upload to with the <code>hwupload</code> filter, +or the device to map to with the <code>hwmap</code> filter. Other filters may also +make use of this parameter when they require a hardware device. Note that this +is typically only required when the input is not already in hardware frames - +when it is, filters will derive the device they require from the context of the +frames they receive as input. +</p> +<p>This is a global setting, so all filters will receive the same device. +</p> +</dd> +<dt><span><samp>-hwaccel[:<var>stream_specifier</var>] <var>hwaccel</var> (<em>input,per-stream</em>)</samp></span></dt> +<dd><p>Use hardware acceleration to decode the matching stream(s). The allowed values +of <var>hwaccel</var> are: +</p><dl compact="compact"> +<dt><span><samp>none</samp></span></dt> +<dd><p>Do not use any hardware acceleration (the default). +</p> +</dd> +<dt><span><samp>auto</samp></span></dt> +<dd><p>Automatically select the hardware acceleration method. +</p> +</dd> +<dt><span><samp>vdpau</samp></span></dt> +<dd><p>Use VDPAU (Video Decode and Presentation API for Unix) hardware acceleration. +</p> +</dd> +<dt><span><samp>dxva2</samp></span></dt> +<dd><p>Use DXVA2 (DirectX Video Acceleration) hardware acceleration. +</p> +</dd> +<dt><span><samp>d3d11va</samp></span></dt> +<dd><p>Use D3D11VA (DirectX Video Acceleration) hardware acceleration. +</p> +</dd> +<dt><span><samp>vaapi</samp></span></dt> +<dd><p>Use VAAPI (Video Acceleration API) hardware acceleration. +</p> +</dd> +<dt><span><samp>qsv</samp></span></dt> +<dd><p>Use the Intel QuickSync Video acceleration for video transcoding. +</p> +<p>Unlike most other values, this option does not enable accelerated decoding (that +is used automatically whenever a qsv decoder is selected), but accelerated +transcoding, without copying the frames into the system memory. +</p> +<p>For it to work, both the decoder and the encoder must support QSV acceleration +and no filters must be used. +</p></dd> +</dl> + +<p>This option has no effect if the selected hwaccel is not available or not +supported by the chosen decoder. +</p> +<p>Note that most acceleration methods are intended for playback and will not be +faster than software decoding on modern CPUs. Additionally, <code>ffmpeg</code> +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. +</p> +</dd> +<dt><span><samp>-hwaccel_device[:<var>stream_specifier</var>] <var>hwaccel_device</var> (<em>input,per-stream</em>)</samp></span></dt> +<dd><p>Select a device to use for hardware acceleration. +</p> +<p>This option only makes sense when the <samp>-hwaccel</samp> option is also specified. +It can either refer to an existing device created with <samp>-init_hw_device</samp> +by name, or it can create a new device as if +‘<samp>-init_hw_device</samp>’ <var>type</var>:<var>hwaccel_device</var> +were called immediately before. +</p> +</dd> +<dt><span><samp>-hwaccels</samp></span></dt> +<dd><p>List all hardware acceleration components enabled in this build of ffmpeg. +Actual runtime availability depends on the hardware and its suitable driver +being installed. +</p> +</dd> +</dl> + +<a name="Audio-Options"></a> +<h3 class="section">5.7 Audio Options<span class="pull-right"><a class="anchor hidden-xs" href="#Audio-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Audio-Options" aria-hidden="true">TOC</a></span></h3> + +<dl compact="compact"> +<dt><span><samp>-aframes <var>number</var> (<em>output</em>)</samp></span></dt> +<dd><p>Set the number of audio frames to output. This is an obsolete alias for +<code>-frames:a</code>, which you should use instead. +</p></dd> +<dt><span><samp>-ar[:<var>stream_specifier</var>] <var>freq</var> (<em>input/output,per-stream</em>)</samp></span></dt> +<dd><p>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. +</p></dd> +<dt><span><samp>-aq <var>q</var> (<em>output</em>)</samp></span></dt> +<dd><p>Set the audio quality (codec-specific, VBR). This is an alias for -q:a. +</p></dd> +<dt><span><samp>-ac[:<var>stream_specifier</var>] <var>channels</var> (<em>input/output,per-stream</em>)</samp></span></dt> +<dd><p>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. +</p></dd> +<dt><span><samp>-an (<em>input/output</em>)</samp></span></dt> +<dd><p>As an input option, blocks all audio streams of a file from being filtered or +being automatically selected or mapped for any output. See <code>-discard</code> +option to disable streams individually. +</p> +<p>As an output option, disables audio recording i.e. automatic selection or +mapping of any audio stream. For full manual control see the <code>-map</code> +option. +</p></dd> +<dt><span><samp>-acodec <var>codec</var> (<em>input/output</em>)</samp></span></dt> +<dd><p>Set the audio codec. This is an alias for <code>-codec:a</code>. +</p></dd> +<dt><span><samp>-sample_fmt[:<var>stream_specifier</var>] <var>sample_fmt</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>Set the audio sample format. Use <code>-sample_fmts</code> to get a list +of supported sample formats. +</p> +</dd> +<dt><span><samp>-af <var>filtergraph</var> (<em>output</em>)</samp></span></dt> +<dd><p>Create the filtergraph specified by <var>filtergraph</var> and use it to +filter the stream. +</p> +<p>This is an alias for <code>-filter:a</code>, see the <a href="#filter_005foption">-filter option</a>. +</p></dd> +</dl> + +<a name="Advanced-Audio-options"></a> +<h3 class="section">5.8 Advanced Audio options<span class="pull-right"><a class="anchor hidden-xs" href="#Advanced-Audio-options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Advanced-Audio-options" aria-hidden="true">TOC</a></span></h3> + +<dl compact="compact"> +<dt><span><samp>-atag <var>fourcc/tag</var> (<em>output</em>)</samp></span></dt> +<dd><p>Force audio tag/fourcc. This is an alias for <code>-tag:a</code>. +</p></dd> +<dt><span><samp>-absf <var>bitstream_filter</var></samp></span></dt> +<dd><p>Deprecated, see -bsf +</p></dd> +<dt><span><samp>-guess_layout_max <var>channels</var> (<em>input,per-stream</em>)</samp></span></dt> +<dd><p>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 <code>ffmpeg</code> 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. +</p></dd> +</dl> + +<a name="Subtitle-options"></a> +<h3 class="section">5.9 Subtitle options<span class="pull-right"><a class="anchor hidden-xs" href="#Subtitle-options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Subtitle-options" aria-hidden="true">TOC</a></span></h3> + +<dl compact="compact"> +<dt><span><samp>-scodec <var>codec</var> (<em>input/output</em>)</samp></span></dt> +<dd><p>Set the subtitle codec. This is an alias for <code>-codec:s</code>. +</p></dd> +<dt><span><samp>-sn (<em>input/output</em>)</samp></span></dt> +<dd><p>As an input option, blocks all subtitle streams of a file from being filtered or +being automatically selected or mapped for any output. See <code>-discard</code> +option to disable streams individually. +</p> +<p>As an output option, disables subtitle recording i.e. automatic selection or +mapping of any subtitle stream. For full manual control see the <code>-map</code> +option. +</p></dd> +<dt><span><samp>-sbsf <var>bitstream_filter</var></samp></span></dt> +<dd><p>Deprecated, see -bsf +</p></dd> +</dl> + +<a name="Advanced-Subtitle-options"></a> +<h3 class="section">5.10 Advanced Subtitle options<span class="pull-right"><a class="anchor hidden-xs" href="#Advanced-Subtitle-options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Advanced-Subtitle-options" aria-hidden="true">TOC</a></span></h3> + +<dl compact="compact"> +<dt><span><samp>-fix_sub_duration</samp></span></dt> +<dd><p>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. +</p> +<p>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. +</p> +</dd> +<dt><span><samp>-canvas_size <var>size</var></samp></span></dt> +<dd><p>Set the size of the canvas used to render subtitles. +</p> +</dd> +</dl> + +<a name="Advanced-options"></a> +<h3 class="section">5.11 Advanced options<span class="pull-right"><a class="anchor hidden-xs" href="#Advanced-options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Advanced-options" aria-hidden="true">TOC</a></span></h3> + +<dl compact="compact"> +<dt><span><samp>-map [-]<var>input_file_id</var>[:<var>stream_specifier</var>][?] | <var>[linklabel]</var> (<em>output</em>)</samp></span></dt> +<dd> +<p>Create one or more streams in the output file. This option has two forms for +specifying the data source(s): the first selects one or more streams from some +input file (specified with <code>-i</code>), the second takes an output from some +complex filtergraph (specified with <code>-filter_complex</code> or +<code>-filter_complex_script</code>). +</p> +<p>In the first form, an output stream is created for every stream from the input +file with the index <var>input_file_id</var>. If <var>stream_specifier</var> is given, +only those streams that match the specifier are used (see the +<a href="#Stream-specifiers">Stream specifiers</a> section for the <var>stream_specifier</var> syntax). +</p> +<p>A <code>-</code> character before the stream identifier creates a "negative" mapping. +It disables matching streams from already created mappings. +</p> +<p>A trailing <code>?</code> after the stream index will allow the map to be +optional: if the map matches no streams the map will be ignored instead +of failing. Note the map will still fail if an invalid input file index +is used; such as if the map refers to a non-existent input. +</p> +<p>An alternative <var>[linklabel]</var> form will map outputs from complex filter +graphs (see the <samp>-filter_complex</samp> option) to the output file. +<var>linklabel</var> must correspond to a defined output link label in the graph. +</p> +<p>This option may be specified multiple times, each adding more streams to the +output file. Any given input stream may also be mapped any number of times as a +source for different output streams, e.g. in order to use different encoding +options and/or filters. The streams are created in the output in the same order +in which the <code>-map</code> options are given on the commandline. +</p> +<p>Using this option disables the default mappings for this output file. +</p> +<p>Examples: +</p> +<dl compact="compact"> +<dt><span><em>map everything</em></span></dt> +<dd><p>To map ALL streams from the first input file to output +</p><div class="example"> +<pre class="example">ffmpeg -i INPUT -map 0 output +</pre></div> + +</dd> +<dt><span><em>select specific stream</em></span></dt> +<dd><p>If you have two audio streams in the first input file, these streams are +identified by <var>0:0</var> and <var>0:1</var>. You can use <code>-map</code> to select which +streams to place in an output file. For example: +</p><div class="example"> +<pre class="example">ffmpeg -i INPUT -map 0:1 out.wav +</pre></div> +<p>will map the second input stream in <samp>INPUT</samp> to the (single) output stream +in <samp>out.wav</samp>. +</p> +</dd> +<dt><span><em>create multiple streams</em></span></dt> +<dd><p>To select the stream with index 2 from input file <samp>a.mov</samp> (specified by the +identifier <var>0:2</var>), and stream with index 6 from input <samp>b.mov</samp> +(specified by the identifier <var>1:6</var>), and copy them to the output file +<samp>out.mov</samp>: +</p><div class="example"> +<pre class="example">ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov +</pre></div> + +</dd> +<dt><span><em>create multiple streams 2</em></span></dt> +<dd><p>To select all video and the third audio stream from an input file: +</p><div class="example"> +<pre class="example">ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT +</pre></div> + +</dd> +<dt><span><em>negative map</em></span></dt> +<dd><p>To map all the streams except the second audio, use negative mappings +</p><div class="example"> +<pre class="example">ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT +</pre></div> + +</dd> +<dt><span><em>optional map</em></span></dt> +<dd><p>To map the video and audio streams from the first input, and using the +trailing <code>?</code>, ignore the audio mapping if no audio streams exist in +the first input: +</p><div class="example"> +<pre class="example">ffmpeg -i INPUT -map 0:v -map 0:a? OUTPUT +</pre></div> + +</dd> +<dt><span><em>map by language</em></span></dt> +<dd><p>To pick the English audio stream: +</p><div class="example"> +<pre class="example">ffmpeg -i INPUT -map 0:m:language:eng OUTPUT +</pre></div> + +</dd> +</dl> + +</dd> +<dt><span><samp>-ignore_unknown</samp></span></dt> +<dd><p>Ignore input streams with unknown type instead of failing if copying +such streams is attempted. +</p> +</dd> +<dt><span><samp>-copy_unknown</samp></span></dt> +<dd><p>Allow input streams with unknown type to be copied instead of failing if copying +such streams is attempted. +</p> +</dd> +<dt><span><samp>-map_channel [<var>input_file_id</var>.<var>stream_specifier</var>.<var>channel_id</var>|-1][?][:<var>output_file_id</var>.<var>stream_specifier</var>]</samp></span></dt> +<dd><p>This option is deprecated and will be removed. It can be replaced by the +<var>pan</var> filter. In some cases it may be easier to use some combination of the +<var>channelsplit</var>, <var>channelmap</var>, or <var>amerge</var> filters. +</p> +<p>Map an audio channel from a given input to an output. If +<var>output_file_id</var>.<var>stream_specifier</var> is not set, the audio channel will +be mapped on all the audio streams. +</p> +<p>Using "-1" instead of +<var>input_file_id</var>.<var>stream_specifier</var>.<var>channel_id</var> will map a muted +channel. +</p> +<p>A trailing <code>?</code> will allow the map_channel to be +optional: if the map_channel matches no channel the map_channel will be ignored instead +of failing. +</p> +<p>For example, assuming <var>INPUT</var> is a stereo audio file, you can switch the +two audio channels with the following command: +</p><div class="example"> +<pre class="example">ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT +</pre></div> + +<p>If you want to mute the first channel and keep the second: +</p><div class="example"> +<pre class="example">ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT +</pre></div> + +<p>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"). +</p> +<p>You can also extract each channel of an input to specific outputs; the following +command extracts two channels of the <var>INPUT</var> audio stream (file 0, stream 0) +to the respective <var>OUTPUT_CH0</var> and <var>OUTPUT_CH1</var> outputs: +</p><div class="example"> +<pre class="example">ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1 +</pre></div> + +<p>The following example splits the channels of a stereo input into two separate +streams, which are put into the same output file: +</p><div class="example"> +<pre class="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 +</pre></div> + +<p>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. +</p> +<p>If you need this feature, a possible workaround is to use the <em>amerge</em> +filter. For example, if you need to merge a media (here <samp>input.mkv</samp>) with 2 +mono audio streams into one single stereo channel audio stream (and keep the +video stream), you can use the following command: +</p><div class="example"> +<pre class="example">ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv +</pre></div> + +<p>To map the first two audio channels from the first input, and using the +trailing <code>?</code>, ignore the audio channel mapping if the first input is +mono instead of stereo: +</p><div class="example"> +<pre class="example">ffmpeg -i INPUT -map_channel 0.0.0 -map_channel 0.0.1? OUTPUT +</pre></div> + +</dd> +<dt><span><samp>-map_metadata[:<var>metadata_spec_out</var>] <var>infile</var>[:<var>metadata_spec_in</var>] (<em>output,per-metadata</em>)</samp></span></dt> +<dd><p>Set metadata information of the next output file from <var>infile</var>. Note that +those are file indices (zero-based), not filenames. +Optional <var>metadata_spec_in/out</var> parameters specify, which metadata to copy. +A metadata specifier can have the following forms: +</p><dl compact="compact"> +<dt><span><samp><var>g</var></samp></span></dt> +<dd><p>global metadata, i.e. metadata that applies to the whole file +</p> +</dd> +<dt><span><samp><var>s</var>[:<var>stream_spec</var>]</samp></span></dt> +<dd><p>per-stream metadata. <var>stream_spec</var> is a stream specifier as described +in the <a href="#Stream-specifiers">Stream specifiers</a> chapter. In an input metadata specifier, the first +matching stream is copied from. In an output metadata specifier, all matching +streams are copied to. +</p> +</dd> +<dt><span><samp><var>c</var>:<var>chapter_index</var></samp></span></dt> +<dd><p>per-chapter metadata. <var>chapter_index</var> is the zero-based chapter index. +</p> +</dd> +<dt><span><samp><var>p</var>:<var>program_index</var></samp></span></dt> +<dd><p>per-program metadata. <var>program_index</var> is the zero-based program index. +</p></dd> +</dl> +<p>If metadata specifier is omitted, it defaults to global. +</p> +<p>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. +</p> +<p>For example to copy metadata from the first stream of the input file to global metadata +of the output file: +</p><div class="example"> +<pre class="example">ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3 +</pre></div> + +<p>To do the reverse, i.e. copy global metadata to all audio streams: +</p><div class="example"> +<pre class="example">ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv +</pre></div> +<p>Note that simple <code>0</code> would work as well in this example, since global +metadata is assumed by default. +</p> +</dd> +<dt><span><samp>-map_chapters <var>input_file_index</var> (<em>output</em>)</samp></span></dt> +<dd><p>Copy chapters from input file with index <var>input_file_index</var> 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. +</p> +</dd> +<dt><span><samp>-benchmark (<em>global</em>)</samp></span></dt> +<dd><p>Show benchmarking information at the end of an encode. +Shows real, system and user time used and maximum memory consumption. +Maximum memory consumption is not supported on all systems, +it will usually display as 0 if not supported. +</p></dd> +<dt><span><samp>-benchmark_all (<em>global</em>)</samp></span></dt> +<dd><p>Show benchmarking information during the encode. +Shows real, system and user time used in various steps (audio/video encode/decode). +</p></dd> +<dt><span><samp>-timelimit <var>duration</var> (<em>global</em>)</samp></span></dt> +<dd><p>Exit after ffmpeg has been running for <var>duration</var> seconds in CPU user time. +</p></dd> +<dt><span><samp>-dump (<em>global</em>)</samp></span></dt> +<dd><p>Dump each input packet to stderr. +</p></dd> +<dt><span><samp>-hex (<em>global</em>)</samp></span></dt> +<dd><p>When dumping packets, also dump the payload. +</p></dd> +<dt><span><samp>-readrate <var>speed</var> (<em>input</em>)</samp></span></dt> +<dd><p>Limit input read speed. +</p> +<p>Its value is a floating-point positive number which represents the maximum duration of +media, in seconds, that should be ingested in one second of wallclock time. +Default value is zero and represents no imposed limitation on speed of ingestion. +Value <code>1</code> represents real-time speed and is equivalent to <code>-re</code>. +</p> +<p>Mainly used to simulate a capture device or live input stream (e.g. when reading from a file). +Should not be used with a low value when input is an actual capture device or live stream as +it may cause packet loss. +</p> +<p>It is useful for when flow speed of output packets is important, such as live streaming. +</p></dd> +<dt><span><samp>-re (<em>input</em>)</samp></span></dt> +<dd><p>Read input at native frame rate. This is equivalent to setting <code>-readrate 1</code>. +</p></dd> +<dt><span><samp>-vsync <var>parameter</var> (<em>global</em>)</samp></span></dt> +<dt><span><samp>-fps_mode[:<var>stream_specifier</var>] <var>parameter</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>Set video sync method / framerate mode. vsync is applied to all output video streams +but can be overridden for a stream by setting fps_mode. vsync is deprecated and will be +removed in the future. +</p> +<p>For compatibility reasons some of the values for vsync can be specified as numbers (shown +in parentheses in the following table). +</p> +<dl compact="compact"> +<dt><span><samp>passthrough (0)</samp></span></dt> +<dd><p>Each frame is passed with its timestamp from the demuxer to the muxer. +</p></dd> +<dt><span><samp>cfr (1)</samp></span></dt> +<dd><p>Frames will be duplicated and dropped to achieve exactly the requested +constant frame rate. +</p></dd> +<dt><span><samp>vfr (2)</samp></span></dt> +<dd><p>Frames are passed through with their timestamp or dropped so as to +prevent 2 frames from having the same timestamp. +</p></dd> +<dt><span><samp>drop</samp></span></dt> +<dd><p>As passthrough but destroys all timestamps, making the muxer generate +fresh timestamps based on frame-rate. +</p></dd> +<dt><span><samp>auto (-1)</samp></span></dt> +<dd><p>Chooses between cfr and vfr depending on muxer capabilities. This is the +default method. +</p></dd> +</dl> + +<p>Note that the timestamps may be further modified by the muxer, after this. +For example, in the case that the format option <samp>avoid_negative_ts</samp> +is enabled. +</p> +<p>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. +</p> +</dd> +<dt><span><samp>-frame_drop_threshold <var>parameter</var></samp></span></dt> +<dd><p>Frame drop threshold, which specifies how much behind video frames can +be before they are dropped. In frame rate units, so 1.0 is one frame. +The default is -1.1. One possible usecase is to avoid framedrops in case +of noisy timestamps or to increase frame drop precision in case of exact +timestamps. +</p> +</dd> +<dt><span><samp>-adrift_threshold <var>time</var></samp></span></dt> +<dd><p>Set the minimum difference between timestamps and audio data (in seconds) to trigger +adding/dropping samples to make it match the timestamps. This option effectively is +a threshold to select between hard (add/drop) and soft (squeeze/stretch) compensation. +<code>-async</code> must be set to a positive value. +</p> +</dd> +<dt><span><samp>-apad <var>parameters</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>Pad the output audio stream(s). This is the same as applying <code>-af apad</code>. +Argument is a string of filter parameters composed the same as with the <code>apad</code> filter. +<code>-shortest</code> must be set for this output for the option to take effect. +</p> +</dd> +<dt><span><samp>-copyts</samp></span></dt> +<dd><p>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. +</p> +<p>Note that, depending on the <samp>vsync</samp> option or on specific muxer +processing (e.g. in case the format option <samp>avoid_negative_ts</samp> +is enabled) the output timestamps may mismatch with the input +timestamps even when this option is selected. +</p> +</dd> +<dt><span><samp>-start_at_zero</samp></span></dt> +<dd><p>When used with <samp>copyts</samp>, shift input timestamps so they start at zero. +</p> +<p>This means that using e.g. <code>-ss 50</code> will make output timestamps start at +50 seconds, regardless of what timestamp the input file started at. +</p> +</dd> +<dt><span><samp>-copytb <var>mode</var></samp></span></dt> +<dd><p>Specify how to set the encoder timebase when stream copying. <var>mode</var> is an +integer numeric value, and can assume one of the following values: +</p> +<dl compact="compact"> +<dt><span><samp>1</samp></span></dt> +<dd><p>Use the demuxer timebase. +</p> +<p>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. +</p> +</dd> +<dt><span><samp>0</samp></span></dt> +<dd><p>Use the decoder timebase. +</p> +<p>The time base is copied to the output encoder from the corresponding input +decoder. +</p> +</dd> +<dt><span><samp>-1</samp></span></dt> +<dd><p>Try to make the choice automatically, in order to generate a sane output. +</p></dd> +</dl> + +<p>Default value is -1. +</p> +</dd> +<dt><span><samp>-enc_time_base[:<var>stream_specifier</var>] <var>timebase</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>Set the encoder timebase. <var>timebase</var> is a floating point number, +and can assume one of the following values: +</p> +<dl compact="compact"> +<dt><span><samp>0</samp></span></dt> +<dd><p>Assign a default value according to the media type. +</p> +<p>For video - use 1/framerate, for audio - use 1/samplerate. +</p> +</dd> +<dt><span><samp>-1</samp></span></dt> +<dd><p>Use the input stream timebase when possible. +</p> +<p>If an input stream is not available, the default timebase will be used. +</p> +</dd> +<dt><span><samp>>0</samp></span></dt> +<dd><p>Use the provided number as the timebase. +</p> +<p>This field can be provided as a ratio of two integers (e.g. 1:24, 1:48000) +or as a floating point number (e.g. 0.04166, 2.0833e-5) +</p></dd> +</dl> + +<p>Default value is 0. +</p> +</dd> +<dt><span><samp>-bitexact (<em>input/output</em>)</samp></span></dt> +<dd><p>Enable bitexact mode for (de)muxer and (de/en)coder +</p></dd> +<dt><span><samp>-shortest (<em>output</em>)</samp></span></dt> +<dd><p>Finish encoding when the shortest output stream ends. +</p> +<p>Note that this option may require buffering frames, which introduces extra +latency. The maximum amount of this latency may be controlled with the +<code>-shortest_buf_duration</code> option. +</p> +</dd> +<dt><span><samp>-shortest_buf_duration <var>duration</var> (<em>output</em>)</samp></span></dt> +<dd><p>The <code>-shortest</code> option may require buffering potentially large amounts +of data when at least one of the streams is "sparse" (i.e. has large gaps +between frames – this is typically the case for subtitles). +</p> +<p>This option controls the maximum duration of buffered frames in seconds. +Larger values may allow the <code>-shortest</code> option to produce more accurate +results, but increase memory use and latency. +</p> +<p>The default value is 10 seconds. +</p> +</dd> +<dt><span><samp>-dts_delta_threshold</samp></span></dt> +<dd><p>Timestamp discontinuity delta threshold. +</p></dd> +<dt><span><samp>-dts_error_threshold <var>seconds</var></samp></span></dt> +<dd><p>Timestamp error delta threshold. This threshold use to discard crazy/damaged +timestamps and the default is 30 hours which is arbitrarily picked and quite +conservative. +</p></dd> +<dt><span><samp>-muxdelay <var>seconds</var> (<em>output</em>)</samp></span></dt> +<dd><p>Set the maximum demux-decode delay. +</p></dd> +<dt><span><samp>-muxpreload <var>seconds</var> (<em>output</em>)</samp></span></dt> +<dd><p>Set the initial demux-decode delay. +</p></dd> +<dt><span><samp>-streamid <var>output-stream-index</var>:<var>new-value</var> (<em>output</em>)</samp></span></dt> +<dd><p>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. +</p> +<p>For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for +an output mpegts file: +</p><div class="example"> +<pre class="example">ffmpeg -i inurl -streamid 0:33 -streamid 1:36 out.ts +</pre></div> + +</dd> +<dt><span><samp>-bsf[:<var>stream_specifier</var>] <var>bitstream_filters</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>Set bitstream filters for matching streams. <var>bitstream_filters</var> is +a comma-separated list of bitstream filters. Use the <code>-bsfs</code> option +to get the list of bitstream filters. +</p><div class="example"> +<pre class="example">ffmpeg -i h264.mp4 -c:v copy -bsf:v h264_mp4toannexb -an out.h264 +</pre></div> +<div class="example"> +<pre class="example">ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt +</pre></div> + +</dd> +<dt><span><samp>-tag[:<var>stream_specifier</var>] <var>codec_tag</var> (<em>input/output,per-stream</em>)</samp></span></dt> +<dd><p>Force a tag/fourcc for matching streams. +</p> +</dd> +<dt><span><samp>-timecode <var>hh</var>:<var>mm</var>:<var>ss</var>SEP<var>ff</var></samp></span></dt> +<dd><p>Specify Timecode for writing. <var>SEP</var> is ’:’ for non drop timecode and ’;’ +(or ’.’) for drop. +</p><div class="example"> +<pre class="example">ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg +</pre></div> + +<span id="filter_005fcomplex_005foption"></span></dd> +<dt><span><samp>-filter_complex <var>filtergraph</var> (<em>global</em>)</samp></span></dt> +<dd><p>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 <samp>-filter</samp> options. <var>filtergraph</var> is a description of +the filtergraph, as described in the “Filtergraph syntax” section of the +ffmpeg-filters manual. +</p> +<p>Input link labels must refer to input streams using the +<code>[file_index:stream_specifier]</code> syntax (i.e. the same as <samp>-map</samp> +uses). If <var>stream_specifier</var> 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. +</p> +<p>Output link labels are referred to with <samp>-map</samp>. Unlabeled outputs are +added to the first output file. +</p> +<p>Note that with this option it is possible to use only lavfi sources without +normal input files. +</p> +<p>For example, to overlay an image over video +</p><div class="example"> +<pre class="example">ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map +'[out]' out.mkv +</pre></div> +<p>Here <code>[0:v]</code> 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. +</p> +<p>Assuming there is only one video stream in each input file, we can omit input +labels, so the above is equivalent to +</p><div class="example"> +<pre class="example">ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map +'[out]' out.mkv +</pre></div> + +<p>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 +</p><div class="example"> +<pre class="example">ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv +</pre></div> + +<p>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. +</p> +<p>For example, to hardcode subtitles on top of a DVB-T recording stored in +MPEG-TS format, delaying the subtitles by 1 second: +</p><div class="example"> +<pre class="example">ffmpeg -i input.ts -filter_complex \ + '[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \ + -sn -map '#0x2dc' output.mkv +</pre></div> +<p>(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) +</p> +<p>To generate 5 seconds of pure red video using lavfi <code>color</code> source: +</p><div class="example"> +<pre class="example">ffmpeg -filter_complex 'color=c=red' -t 5 out.mkv +</pre></div> + +</dd> +<dt><span><samp>-filter_complex_threads <var>nb_threads</var> (<em>global</em>)</samp></span></dt> +<dd><p>Defines how many threads are used to process a filter_complex graph. +Similar to filter_threads but used for <code>-filter_complex</code> graphs only. +The default is the number of available CPUs. +</p> +</dd> +<dt><span><samp>-lavfi <var>filtergraph</var> (<em>global</em>)</samp></span></dt> +<dd><p>Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or +outputs. Equivalent to <samp>-filter_complex</samp>. +</p> +</dd> +<dt><span><samp>-filter_complex_script <var>filename</var> (<em>global</em>)</samp></span></dt> +<dd><p>This option is similar to <samp>-filter_complex</samp>, the only difference is that +its argument is the name of the file from which a complex filtergraph +description is to be read. +</p> +</dd> +<dt><span><samp>-accurate_seek (<em>input</em>)</samp></span></dt> +<dd><p>This option enables or disables accurate seeking in input files with the +<samp>-ss</samp> option. It is enabled by default, so seeking is accurate when +transcoding. Use <samp>-noaccurate_seek</samp> to disable it, which may be useful +e.g. when copying some streams and transcoding the others. +</p> +</dd> +<dt><span><samp>-seek_timestamp (<em>input</em>)</samp></span></dt> +<dd><p>This option enables or disables seeking by timestamp in input files with the +<samp>-ss</samp> option. It is disabled by default. If enabled, the argument +to the <samp>-ss</samp> option is considered an actual timestamp, and is not +offset by the start time of the file. This matters only for files which do +not start from timestamp 0, such as transport streams. +</p> +</dd> +<dt><span><samp>-thread_queue_size <var>size</var> (<em>input/output</em>)</samp></span></dt> +<dd><p>For input, this option sets the maximum number of queued packets when reading +from the file or device. With low latency / high rate live streams, packets may +be discarded if they are not read in a timely manner; setting this value can +force ffmpeg to use a separate input thread and read packets as soon as they +arrive. By default ffmpeg only does this if multiple inputs are specified. +</p> +<p>For output, this option specified the maximum number of packets that may be +queued to each muxing thread. +</p> +</dd> +<dt><span><samp>-sdp_file <var>file</var> (<em>global</em>)</samp></span></dt> +<dd><p>Print sdp information for an output stream to <var>file</var>. +This allows dumping sdp information when at least one output isn’t an +rtp stream. (Requires at least one of the output formats to be rtp). +</p> +</dd> +<dt><span><samp>-discard (<em>input</em>)</samp></span></dt> +<dd><p>Allows discarding specific streams or frames from streams. +Any input stream can be fully discarded, using value <code>all</code> whereas +selective discarding of frames from a stream occurs at the demuxer +and is not supported by all demuxers. +</p> +<dl compact="compact"> +<dt><span><samp>none</samp></span></dt> +<dd><p>Discard no frame. +</p> +</dd> +<dt><span><samp>default</samp></span></dt> +<dd><p>Default, which discards no frames. +</p> +</dd> +<dt><span><samp>noref</samp></span></dt> +<dd><p>Discard all non-reference frames. +</p> +</dd> +<dt><span><samp>bidir</samp></span></dt> +<dd><p>Discard all bidirectional frames. +</p> +</dd> +<dt><span><samp>nokey</samp></span></dt> +<dd><p>Discard all frames excepts keyframes. +</p> +</dd> +<dt><span><samp>all</samp></span></dt> +<dd><p>Discard all frames. +</p></dd> +</dl> + +</dd> +<dt><span><samp>-abort_on <var>flags</var> (<em>global</em>)</samp></span></dt> +<dd><p>Stop and abort on various conditions. The following flags are available: +</p> +<dl compact="compact"> +<dt><span><samp>empty_output</samp></span></dt> +<dd><p>No packets were passed to the muxer, the output is empty. +</p></dd> +<dt><span><samp>empty_output_stream</samp></span></dt> +<dd><p>No packets were passed to the muxer in some of the output streams. +</p></dd> +</dl> + +</dd> +<dt><span><samp>-max_error_rate (<em>global</em>)</samp></span></dt> +<dd><p>Set fraction of decoding frame failures across all inputs which when crossed +ffmpeg will return exit code 69. Crossing this threshold does not terminate +processing. Range is a floating-point number between 0 to 1. Default is 2/3. +</p> +</dd> +<dt><span><samp>-xerror (<em>global</em>)</samp></span></dt> +<dd><p>Stop and exit on error +</p> +</dd> +<dt><span><samp>-max_muxing_queue_size <var>packets</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>When transcoding audio and/or video streams, ffmpeg will not begin writing into +the output until it has one packet for each such stream. While waiting for that +to happen, packets for other streams are buffered. This option sets the size of +this buffer, in packets, for the matching output stream. +</p> +<p>The default value of this option should be high enough for most uses, so only +touch this option if you are sure that you need it. +</p> +</dd> +<dt><span><samp>-muxing_queue_data_threshold <var>bytes</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>This is a minimum threshold until which the muxing queue size is not taken into +account. Defaults to 50 megabytes per stream, and is based on the overall size +of packets passed to the muxer. +</p> +</dd> +<dt><span><samp>-auto_conversion_filters (<em>global</em>)</samp></span></dt> +<dd><p>Enable automatically inserting format conversion filters in all filter +graphs, including those defined by <samp>-vf</samp>, <samp>-af</samp>, +<samp>-filter_complex</samp> and <samp>-lavfi</samp>. If filter format negotiation +requires a conversion, the initialization of the filters will fail. +Conversions can still be performed by inserting the relevant conversion +filter (scale, aresample) in the graph. +On by default, to explicitly disable it you need to specify +<code>-noauto_conversion_filters</code>. +</p> +</dd> +<dt><span><samp>-bits_per_raw_sample[:<var>stream_specifier</var>] <var>value</var> (<em>output,per-stream</em>)</samp></span></dt> +<dd><p>Declare the number of bits per raw sample in the given output stream to be +<var>value</var>. Note that this option sets the information provided to the +encoder/muxer, it does not change the stream to conform to this value. Setting +values that do not match the stream properties may result in encoding failures +or invalid output files. +</p> +</dd> +</dl> + +<a name="Preset-files"></a> +<h3 class="section">5.12 Preset files<span class="pull-right"><a class="anchor hidden-xs" href="#Preset-files" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Preset-files" aria-hidden="true">TOC</a></span></h3> +<p>A preset file contains a sequence of <var>option</var>=<var>value</var> 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 <samp>presets</samp> directory in the FFmpeg source tree for examples. +</p> +<p>There are two types of preset files: ffpreset and avpreset files. +</p> +<a name="ffpreset-files"></a> +<h4 class="subsection">5.12.1 ffpreset files<span class="pull-right"><a class="anchor hidden-xs" href="#ffpreset-files" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-ffpreset-files" aria-hidden="true">TOC</a></span></h4> +<p>ffpreset files are specified with the <code>vpre</code>, <code>apre</code>, +<code>spre</code>, and <code>fpre</code> options. The <code>fpre</code> 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>, <code>apre</code>, and +<code>spre</code> options, the options specified in a preset file are +applied to the currently selected codec of the same type as the preset +option. +</p> +<p>The argument passed to the <code>vpre</code>, <code>apre</code>, and <code>spre</code> +preset options identifies the preset file to use according to the +following rules: +</p> +<p>First ffmpeg searches for a file named <var>arg</var>.ffpreset in the +directories <samp>$FFMPEG_DATADIR</samp> (if set), and <samp>$HOME/.ffmpeg</samp>, and in +the datadir defined at configuration time (usually <samp>PREFIX/share/ffmpeg</samp>) +or in a <samp>ffpresets</samp> folder along the executable on win32, +in that order. For example, if the argument is <code>libvpx-1080p</code>, it will +search for the file <samp>libvpx-1080p.ffpreset</samp>. +</p> +<p>If no such file is found, then ffmpeg will search for a file named +<var>codec_name</var>-<var>arg</var>.ffpreset in the above-mentioned +directories, where <var>codec_name</var> 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</code> and use <code>-vpre 1080p</code>, +then it will search for the file <samp>libvpx-1080p.ffpreset</samp>. +</p> +<a name="avpreset-files"></a> +<h4 class="subsection">5.12.2 avpreset files<span class="pull-right"><a class="anchor hidden-xs" href="#avpreset-files" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-avpreset-files" aria-hidden="true">TOC</a></span></h4> +<p>avpreset files are specified with the <code>pre</code> option. They work similar to +ffpreset files, but they only allow encoder- specific options. Therefore, an +<var>option</var>=<var>value</var> pair specifying an encoder cannot be used. +</p> +<p>When the <code>pre</code> option is specified, ffmpeg will look for files with the +suffix .avpreset in the directories <samp>$AVCONV_DATADIR</samp> (if set), and +<samp>$HOME/.avconv</samp>, and in the datadir defined at configuration time (usually +<samp>PREFIX/share/ffmpeg</samp>), in that order. +</p> +<p>First ffmpeg searches for a file named <var>codec_name</var>-<var>arg</var>.avpreset in +the above-mentioned directories, where <var>codec_name</var> 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</code> and use <code>-pre 1080p</code>, then it will +search for the file <samp>libvpx-1080p.avpreset</samp>. +</p> +<p>If no such file is found, then ffmpeg will search for a file named +<var>arg</var>.avpreset in the same directories. +</p> + +<a name="Examples-1"></a> +<h2 class="chapter">6 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-1" aria-hidden="true">TOC</a></span></h2> + +<a name="Video-and-Audio-grabbing"></a> +<h3 class="section">6.1 Video and Audio grabbing<span class="pull-right"><a class="anchor hidden-xs" href="#Video-and-Audio-grabbing" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Video-and-Audio-grabbing" aria-hidden="true">TOC</a></span></h3> + +<p>If you specify the input format and device then ffmpeg can grab video +and audio directly. +</p> +<div class="example"> +<pre class="example">ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg +</pre></div> + +<p>Or with an ALSA audio source (mono input, card id 1) instead of OSS: +</p><div class="example"> +<pre class="example">ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg +</pre></div> + +<p>Note that you must activate the right video source and channel before +launching ffmpeg with any TV viewer such as +<a href="http://linux.bytesex.org/xawtv/">xawtv</a> by Gerd Knorr. You also +have to set the audio recording levels correctly with a +standard mixer. +</p> +<a name="X11-grabbing"></a> +<h3 class="section">6.2 X11 grabbing<span class="pull-right"><a class="anchor hidden-xs" href="#X11-grabbing" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-X11-grabbing" aria-hidden="true">TOC</a></span></h3> + +<p>Grab the X11 display with ffmpeg via +</p> +<div class="example"> +<pre class="example">ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0 /tmp/out.mpg +</pre></div> + +<p>0.0 is display.screen number of your X11 server, same as +the DISPLAY environment variable. +</p> +<div class="example"> +<pre class="example">ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0+10,20 /tmp/out.mpg +</pre></div> + +<p>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. +</p> +<a name="Video-and-Audio-file-format-conversion"></a> +<h3 class="section">6.3 Video and Audio file format conversion<span class="pull-right"><a class="anchor hidden-xs" href="#Video-and-Audio-file-format-conversion" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Video-and-Audio-file-format-conversion" aria-hidden="true">TOC</a></span></h3> + +<p>Any supported file format and protocol can serve as input to ffmpeg: +</p> +<p>Examples: +</p><ul> +<li> You can use YUV files as input: + +<div class="example"> +<pre class="example">ffmpeg -i /tmp/test%d.Y /tmp/out.mpg +</pre></div> + +<p>It will use the files: +</p><div class="example"> +<pre class="example">/tmp/test0.Y, /tmp/test0.U, /tmp/test0.V, +/tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc... +</pre></div> + +<p>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 <samp>-s</samp> option +if ffmpeg cannot guess it. +</p> +</li><li> You can input from a raw YUV420P file: + +<div class="example"> +<pre class="example">ffmpeg -i /tmp/test.yuv /tmp/out.avi +</pre></div> + +<p>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. +</p> +</li><li> You can output to a raw YUV420P file: + +<div class="example"> +<pre class="example">ffmpeg -i mydivx.avi hugefile.yuv +</pre></div> + +</li><li> You can set several input files and output files: + +<div class="example"> +<pre class="example">ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg +</pre></div> + +<p>Converts the audio file a.wav and the raw YUV video file a.yuv +to MPEG file a.mpg. +</p> +</li><li> You can also do audio and video conversions at the same time: + +<div class="example"> +<pre class="example">ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2 +</pre></div> + +<p>Converts a.wav to MPEG audio at 22050 Hz sample rate. +</p> +</li><li> You can encode to several formats at the same time and define a +mapping from input stream to output streams: + +<div class="example"> +<pre class="example">ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2 +</pre></div> + +<p>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. +</p> +</li><li> You can transcode decrypted VOBs: + +<div class="example"> +<pre class="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 +</pre></div> + +<p>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</code> to configure. +The mapping is particularly useful for DVD transcoding +to get the desired audio language. +</p> +<p>NOTE: To see the supported input formats, use <code>ffmpeg -demuxers</code>. +</p> +</li><li> You can extract images from a video, or create a video from many images: + +<p>For extracting images from a video: +</p><div class="example"> +<pre class="example">ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg +</pre></div> + +<p>This will extract one video frame per second from the video and will +output them in files named <samp>foo-001.jpeg</samp>, <samp>foo-002.jpeg</samp>, +etc. Images will be rescaled to fit the new WxH values. +</p> +<p>If you want to extract just a limited number of frames, you can use the +above command in combination with the <code>-frames:v</code> or <code>-t</code> option, +or in combination with -ss to start extracting from a certain point in time. +</p> +<p>For creating a video from many images: +</p><div class="example"> +<pre class="example">ffmpeg -f image2 -framerate 12 -i foo-%03d.jpeg -s WxH foo.avi +</pre></div> + +<p>The syntax <code>foo-%03d.jpeg</code> 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. +</p> +<p>When importing an image sequence, -i also supports expanding +shell-like wildcard patterns (globbing) internally, by selecting the +image2-specific <code>-pattern_type glob</code> option. +</p> +<p>For example, for creating a video from filenames matching the glob pattern +<code>foo-*.jpeg</code>: +</p><div class="example"> +<pre class="example">ffmpeg -f image2 -pattern_type glob -framerate 12 -i 'foo-*.jpeg' -s WxH foo.avi +</pre></div> + +</li><li> You can put many streams of the same type in the output: + +<div class="example"> +<pre class="example">ffmpeg -i test1.avi -i test2.avi -map 1:1 -map 1:0 -map 0:1 -map 0:0 -c copy -y test12.nut +</pre></div> + +<p>The resulting output file <samp>test12.nut</samp> will contain the first four streams +from the input files in reverse order. +</p> +</li><li> To force CBR video output: +<div class="example"> +<pre class="example">ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v +</pre></div> + +</li><li> The four options lmin, lmax, mblmin and mblmax use ’lambda’ units, +but you may use the QP2LAMBDA constant to easily convert from ’q’ units: +<div class="example"> +<pre class="example">ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext +</pre></div> + +</li></ul> + + +<a name="See-Also"></a> +<h2 class="chapter">7 See Also<span class="pull-right"><a class="anchor hidden-xs" href="#See-Also" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-See-Also" aria-hidden="true">TOC</a></span></h2> + +<p><a href="ffmpeg-all.html">ffmpeg-all</a>, +<a href="ffplay.html">ffplay</a>, <a href="ffprobe.html">ffprobe</a>, +<a href="ffmpeg-utils.html">ffmpeg-utils</a>, +<a href="ffmpeg-scaler.html">ffmpeg-scaler</a>, +<a href="ffmpeg-resampler.html">ffmpeg-resampler</a>, +<a href="ffmpeg-codecs.html">ffmpeg-codecs</a>, +<a href="ffmpeg-bitstream-filters.html">ffmpeg-bitstream-filters</a>, +<a href="ffmpeg-formats.html">ffmpeg-formats</a>, +<a href="ffmpeg-devices.html">ffmpeg-devices</a>, +<a href="ffmpeg-protocols.html">ffmpeg-protocols</a>, +<a href="ffmpeg-filters.html">ffmpeg-filters</a> +</p> + +<a name="Authors"></a> +<h2 class="chapter">8 Authors<span class="pull-right"><a class="anchor hidden-xs" href="#Authors" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Authors" aria-hidden="true">TOC</a></span></h2> + +<p>The FFmpeg developers. +</p> +<p>For details about the authorship, see the Git history of the project +(git://source.ffmpeg.org/ffmpeg), e.g. by typing the command +<code>git log</code> in the FFmpeg source directory, or browsing the +online repository at <a href="http://source.ffmpeg.org">http://source.ffmpeg.org</a>. +</p> +<p>Maintainers for the specific components are listed in the file +<samp>MAINTAINERS</samp> in the source code tree. +</p> + + <p style="font-size: small;"> + This document was generated using <a href="https://www.gnu.org/software/texinfo/"><em>makeinfo</em></a>. + </p> + </div> + </body> +</html> |