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1947 lines
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<head>
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<title>FFmpeg documentation : ffmpeg </title>
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<meta name="description" content="ffmpeg Documentation: ">
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<meta name="keywords" content="FFmpeg documentation : ffmpeg ">
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<div id="container">
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<div id="body">
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<a name="SEC_Top"></a>
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<h1 class="settitle">ffmpeg Documentation</h1>
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<a name="SEC_Contents"></a>
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<h1>Table of Contents</h1>
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<div class="contents">
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<ul class="toc">
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<li><a name="toc-Synopsis" href="#Synopsis">1. Synopsis</a></li>
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<li><a name="toc-Description" href="#Description">2. Description</a></li>
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<li><a name="toc-Detailed-description" href="#Detailed-description">3. Detailed description</a>
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<ul class="toc">
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<li><a name="toc-Filtering" href="#Filtering">3.1 Filtering</a>
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<ul class="toc">
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<li><a name="toc-Simple-filtergraphs" href="#Simple-filtergraphs">3.1.1 Simple filtergraphs</a></li>
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<li><a name="toc-Complex-filtergraphs" href="#Complex-filtergraphs">3.1.2 Complex filtergraphs</a></li>
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</ul></li>
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<li><a name="toc-Stream-copy" href="#Stream-copy">3.2 Stream copy</a></li>
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</ul></li>
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<li><a name="toc-Stream-selection" href="#Stream-selection">4. Stream selection</a></li>
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<li><a name="toc-Options" href="#Options">5. Options</a>
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<ul class="toc">
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<li><a name="toc-Stream-specifiers-1" href="#Stream-specifiers-1">5.1 Stream specifiers</a></li>
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<li><a name="toc-Generic-options" href="#Generic-options">5.2 Generic options</a></li>
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<li><a name="toc-AVOptions" href="#AVOptions">5.3 AVOptions</a></li>
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<li><a name="toc-Main-options" href="#Main-options">5.4 Main options</a></li>
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<li><a name="toc-Video-Options" href="#Video-Options">5.5 Video Options</a></li>
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<li><a name="toc-Advanced-Video-Options" href="#Advanced-Video-Options">5.6 Advanced Video Options</a></li>
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<li><a name="toc-Audio-Options" href="#Audio-Options">5.7 Audio Options</a></li>
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<li><a name="toc-Advanced-Audio-options_003a" href="#Advanced-Audio-options_003a">5.8 Advanced Audio options:</a></li>
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<li><a name="toc-Subtitle-options_003a" href="#Subtitle-options_003a">5.9 Subtitle options:</a></li>
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<li><a name="toc-Advanced-Subtitle-options_003a" href="#Advanced-Subtitle-options_003a">5.10 Advanced Subtitle options:</a></li>
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<li><a name="toc-Advanced-options" href="#Advanced-options">5.11 Advanced options</a></li>
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<li><a name="toc-Preset-files" href="#Preset-files">5.12 Preset files</a></li>
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</ul></li>
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<li><a name="toc-Tips" href="#Tips">6. Tips</a></li>
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<li><a name="toc-Examples" href="#Examples">7. Examples</a>
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<ul class="toc">
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<li><a name="toc-Preset-files-1" href="#Preset-files-1">7.1 Preset files</a></li>
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<li><a name="toc-Video-and-Audio-grabbing" href="#Video-and-Audio-grabbing">7.2 Video and Audio grabbing</a></li>
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<li><a name="toc-X11-grabbing" href="#X11-grabbing">7.3 X11 grabbing</a></li>
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<li><a name="toc-Video-and-Audio-file-format-conversion" href="#Video-and-Audio-file-format-conversion">7.4 Video and Audio file format conversion</a></li>
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</ul></li>
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<li><a name="toc-See-Also" href="#See-Also">8. See Also</a></li>
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<li><a name="toc-Authors" href="#Authors">9. Authors</a></li>
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</ul>
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</div>
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<a name="Synopsis"></a>
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<h1 class="chapter"><a href="ffmpeg.html#toc-Synopsis">1. Synopsis</a></h1>
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<p>ffmpeg [<var>global_options</var>] {[<var>input_file_options</var>] -i ‘<tt>input_file</tt>’} ... {[<var>output_file_options</var>] ‘<tt>output_file</tt>’} ...
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</p>
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<a name="Description"></a>
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<h1 class="chapter"><a href="ffmpeg.html#toc-Description">2. Description</a></h1>
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<p><code>ffmpeg</code> is a very fast video and audio converter that can also grab from
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a live audio/video source. It can also convert between arbitrary sample
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rates and resize video on the fly with a high quality polyphase filter.
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</p>
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<p><code>ffmpeg</code> reads from an arbitrary number of input "files" (which can be regular
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files, pipes, network streams, grabbing devices, etc.), specified by the
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<code>-i</code> option, and writes to an arbitrary number of output "files", which are
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specified by a plain output filename. Anything found on the command line which
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cannot be interpreted as an option is considered to be an output filename.
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</p>
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<p>Each input or output file can, in principle, contain any number of streams of
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different types (video/audio/subtitle/attachment/data). The allowed number and/or
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types of streams may be limited by the container format. Selecting which
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streams from which inputs will go into which output is either done automatically
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or with the <code>-map</code> option (see the Stream selection chapter).
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</p>
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<p>To refer to input files in options, you must use their indices (0-based). E.g.
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the first input file is <code>0</code>, the second is <code>1</code>, etc. Similarly, streams
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within a file are referred to by their indices. E.g. <code>2:3</code> refers to the
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fourth stream in the third input file. Also see the Stream specifiers chapter.
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</p>
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<p>As a general rule, options are applied to the next specified
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file. Therefore, order is important, and you can have the same
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option on the command line multiple times. Each occurrence is
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then applied to the next input or output file.
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Exceptions from this rule are the global options (e.g. verbosity level),
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which should be specified first.
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</p>
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<p>Do not mix input and output files – first specify all input files, then all
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output files. Also do not mix options which belong to different files. All
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options apply ONLY to the next input or output file and are reset between files.
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</p>
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<ul>
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<li>
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To set the video bitrate of the output file to 64 kbit/s:
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<table><tr><td> </td><td><pre class="example">ffmpeg -i input.avi -b:v 64k -bufsize 64k output.avi
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</pre></td></tr></table>
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</li><li>
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To force the frame rate of the output file to 24 fps:
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<table><tr><td> </td><td><pre class="example">ffmpeg -i input.avi -r 24 output.avi
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</pre></td></tr></table>
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</li><li>
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To force the frame rate of the input file (valid for raw formats only)
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to 1 fps and the frame rate of the output file to 24 fps:
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<table><tr><td> </td><td><pre class="example">ffmpeg -r 1 -i input.m2v -r 24 output.avi
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</pre></td></tr></table>
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</li></ul>
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<p>The format option may be needed for raw input files.
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</p>
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<a name="Detailed-description"></a>
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<h1 class="chapter"><a href="ffmpeg.html#toc-Detailed-description">3. Detailed description</a></h1>
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<p>The transcoding process in <code>ffmpeg</code> for each output can be described by
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the following diagram:
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</p>
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<table><tr><td> </td><td><pre class="example"> _______ ______________
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| | | |
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| input | demuxer | encoded data | decoder
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| file | ---------> | packets | -----+
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|_______| |______________| |
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v
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_________
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| |
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| decoded |
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| frames |
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|_________|
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________ ______________ |
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| | | | |
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| output | <-------- | encoded data | <----+
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| file | muxer | packets | encoder
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|________| |______________|
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</pre></td></tr></table>
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<p><code>ffmpeg</code> calls the libavformat library (containing demuxers) to read
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input files and get packets containing encoded data from them. When there are
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multiple input files, <code>ffmpeg</code> tries to keep them synchronized by
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tracking lowest timestamp on any active input stream.
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</p>
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<p>Encoded packets are then passed to the decoder (unless streamcopy is selected
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for the stream, see further for a description). The decoder produces
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uncompressed frames (raw video/PCM audio/...) which can be processed further by
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filtering (see next section). After filtering, the frames are passed to the
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encoder, which encodes them and outputs encoded packets. Finally those are
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passed to the muxer, which writes the encoded packets to the output file.
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</p>
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<a name="Filtering"></a>
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<h2 class="section"><a href="ffmpeg.html#toc-Filtering">3.1 Filtering</a></h2>
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<p>Before encoding, <code>ffmpeg</code> can process raw audio and video frames using
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filters from the libavfilter library. Several chained filters form a filter
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graph. <code>ffmpeg</code> distinguishes between two types of filtergraphs:
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simple and complex.
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</p>
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<a name="Simple-filtergraphs"></a>
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<h3 class="subsection"><a href="ffmpeg.html#toc-Simple-filtergraphs">3.1.1 Simple filtergraphs</a></h3>
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<p>Simple filtergraphs are those that have exactly one input and output, both of
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the same type. In the above diagram they can be represented by simply inserting
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an additional step between decoding and encoding:
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</p>
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<table><tr><td> </td><td><pre class="example"> _________ ______________
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| | | |
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| decoded | | encoded data |
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| frames |\ _ | packets |
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|_________| \ /||______________|
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\ __________ /
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simple _\|| | / encoder
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filtergraph | filtered |/
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| frames |
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|__________|
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</pre></td></tr></table>
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<p>Simple filtergraphs are configured with the per-stream ‘<samp>-filter</samp>’ option
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(with ‘<samp>-vf</samp>’ and ‘<samp>-af</samp>’ aliases for video and audio respectively).
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A simple filtergraph for video can look for example like this:
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</p>
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<table><tr><td> </td><td><pre class="example"> _______ _____________ _______ ________
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| | | | | | | |
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| input | ---> | deinterlace | ---> | scale | ---> | output |
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|_______| |_____________| |_______| |________|
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</pre></td></tr></table>
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<p>Note that some filters change frame properties but not frame contents. E.g. the
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<code>fps</code> filter in the example above changes number of frames, but does not
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touch the frame contents. Another example is the <code>setpts</code> filter, which
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only sets timestamps and otherwise passes the frames unchanged.
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</p>
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<a name="Complex-filtergraphs"></a>
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<h3 class="subsection"><a href="ffmpeg.html#toc-Complex-filtergraphs">3.1.2 Complex filtergraphs</a></h3>
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<p>Complex filtergraphs are those which cannot be described as simply a linear
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processing chain applied to one stream. This is the case, for example, when the graph has
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more than one input and/or output, or when output stream type is different from
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input. They can be represented with the following diagram:
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</p>
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<table><tr><td> </td><td><pre class="example"> _________
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| |
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| input 0 |\ __________
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|_________| \ | |
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\ _________ /| output 0 |
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\ | | / |__________|
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_________ \| complex | /
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| | | |/
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| input 1 |---->| filter |\
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|_________| | | \ __________
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/| graph | \ | |
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/ | | \| output 1 |
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_________ / |_________| |__________|
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| | /
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| input 2 |/
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|_________|
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</pre></td></tr></table>
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<p>Complex filtergraphs are configured with the ‘<samp>-filter_complex</samp>’ option.
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Note that this option is global, since a complex filtergraph, by its nature,
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cannot be unambiguously associated with a single stream or file.
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</p>
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<p>The ‘<samp>-lavfi</samp>’ option is equivalent to ‘<samp>-filter_complex</samp>’.
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</p>
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<p>A trivial example of a complex filtergraph is the <code>overlay</code> filter, which
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has two video inputs and one video output, containing one video overlaid on top
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of the other. Its audio counterpart is the <code>amix</code> filter.
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</p>
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<a name="Stream-copy"></a>
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<h2 class="section"><a href="ffmpeg.html#toc-Stream-copy">3.2 Stream copy</a></h2>
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<p>Stream copy is a mode selected by supplying the <code>copy</code> parameter to the
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‘<samp>-codec</samp>’ option. It makes <code>ffmpeg</code> omit the decoding and encoding
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step for the specified stream, so it does only demuxing and muxing. It is useful
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for changing the container format or modifying container-level metadata. The
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diagram above will, in this case, simplify to this:
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</p>
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<table><tr><td> </td><td><pre class="example"> _______ ______________ ________
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| | | | | |
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| input | demuxer | encoded data | muxer | output |
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| file | ---------> | packets | -------> | file |
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|_______| |______________| |________|
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</pre></td></tr></table>
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<p>Since there is no decoding or encoding, it is very fast and there is no quality
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loss. However, it might not work in some cases because of many factors. Applying
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filters is obviously also impossible, since filters work on uncompressed data.
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</p>
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<a name="Stream-selection"></a>
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<h1 class="chapter"><a href="ffmpeg.html#toc-Stream-selection">4. Stream selection</a></h1>
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<p>By default, <code>ffmpeg</code> includes only one stream of each type (video, audio, subtitle)
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present in the input files and adds them to each output file. It picks the
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"best" of each based upon the following criteria: for video, it is the stream
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with the highest resolution, for audio, it is the stream with the most channels, for
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subtitles, it is the first subtitle stream. In the case where several streams of
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the same type rate equally, the stream with the lowest index is chosen.
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</p>
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<p>You can disable some of those defaults by using the <code>-vn/-an/-sn</code> options. For
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full manual control, use the <code>-map</code> option, which disables the defaults just
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described.
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</p>
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<a name="Options"></a>
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<h1 class="chapter"><a href="ffmpeg.html#toc-Options">5. Options</a></h1>
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<p>All the numerical options, if not specified otherwise, accept a string
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representing a number as input, which may be followed by one of the SI
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unit prefixes, for example: ’K’, ’M’, or ’G’.
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</p>
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<p>If ’i’ is appended to the SI unit prefix, the complete prefix will be
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interpreted as a unit prefix for binary multiplies, which are based on
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powers of 1024 instead of powers of 1000. Appending ’B’ to the SI unit
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prefix multiplies the value by 8. This allows using, for example:
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’KB’, ’MiB’, ’G’ and ’B’ as number suffixes.
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</p>
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<p>Options which do not take arguments are boolean options, and set the
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corresponding value to true. They can be set to false by prefixing
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the option name with "no". For example using "-nofoo"
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will set the boolean option with name "foo" to false.
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</p>
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<p><a name="Stream-specifiers"></a>
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</p><a name="Stream-specifiers-1"></a>
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<h2 class="section"><a href="ffmpeg.html#toc-Stream-specifiers-1">5.1 Stream specifiers</a></h2>
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<p>Some options are applied per-stream, e.g. bitrate or codec. Stream specifiers
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are used to precisely specify which stream(s) a given option belongs to.
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</p>
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<p>A stream specifier is a string generally appended to the option name and
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separated from it by a colon. E.g. <code>-codec:a:1 ac3</code> contains the
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<code>a:1</code> stream specifier, which matches the second audio stream. Therefore, it
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would select the ac3 codec for the second audio stream.
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</p>
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<p>A stream specifier can match several streams, so that the option is applied to all
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of them. E.g. the stream specifier in <code>-b:a 128k</code> matches all audio
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streams.
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</p>
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<p>An empty stream specifier matches all streams. For example, <code>-codec copy</code>
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or <code>-codec: copy</code> would copy all the streams without reencoding.
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</p>
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<p>Possible forms of stream specifiers are:
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</p><dl compact="compact">
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<dt> ‘<samp><var>stream_index</var></samp>’</dt>
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<dd><p>Matches the stream with this index. E.g. <code>-threads:1 4</code> would set the
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thread count for the second stream to 4.
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</p></dd>
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<dt> ‘<samp><var>stream_type</var>[:<var>stream_index</var>]</samp>’</dt>
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<dd><p><var>stream_type</var> is one of following: ’v’ for video, ’a’ for audio, ’s’ for subtitle,
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’d’ for data, and ’t’ for attachments. If <var>stream_index</var> is given, then it matches
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stream number <var>stream_index</var> of this type. Otherwise, it matches all
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streams of this type.
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</p></dd>
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<dt> ‘<samp>p:<var>program_id</var>[:<var>stream_index</var>]</samp>’</dt>
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<dd><p>If <var>stream_index</var> is given, then it matches the stream with number <var>stream_index</var>
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in the program with the id <var>program_id</var>. Otherwise, it matches all streams in the
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program.
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</p></dd>
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<dt> ‘<samp>#<var>stream_id</var> or i:<var>stream_id</var></samp>’</dt>
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<dd><p>Match the stream by stream id (e.g. PID in MPEG-TS container).
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</p></dd>
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</dl>
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<a name="Generic-options"></a>
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<h2 class="section"><a href="ffmpeg.html#toc-Generic-options">5.2 Generic options</a></h2>
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<p>These options are shared amongst the ff* tools.
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</p>
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<dl compact="compact">
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<dt> ‘<samp>-L</samp>’</dt>
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<dd><p>Show license.
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</p>
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</dd>
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<dt> ‘<samp>-h, -?, -help, --help [<var>arg</var>]</samp>’</dt>
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<dd><p>Show help. An optional parameter may be specified to print help about a specific
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item. If no argument is specified, only basic (non advanced) tool
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options are shown.
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</p>
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<p>Possible values of <var>arg</var> are:
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</p><dl compact="compact">
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<dt> ‘<samp>long</samp>’</dt>
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<dd><p>Print advanced tool options in addition to the basic tool options.
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</p>
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</dd>
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<dt> ‘<samp>full</samp>’</dt>
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<dd><p>Print complete list of options, including shared and private options
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for encoders, decoders, demuxers, muxers, filters, etc.
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</p>
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</dd>
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<dt> ‘<samp>decoder=<var>decoder_name</var></samp>’</dt>
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<dd><p>Print detailed information about the decoder named <var>decoder_name</var>. Use the
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‘<samp>-decoders</samp>’ option to get a list of all decoders.
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</p>
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</dd>
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<dt> ‘<samp>encoder=<var>encoder_name</var></samp>’</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> ‘<samp>demuxer=<var>demuxer_name</var></samp>’</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> ‘<samp>muxer=<var>muxer_name</var></samp>’</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> ‘<samp>filter=<var>filter_name</var></samp>’</dt>
|
|
<dd><p>Print detailed information about the filter name <var>filter_name</var>. Use the
|
|
‘<samp>-filters</samp>’ option to get a list of all filters.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt> ‘<samp>-version</samp>’</dt>
|
|
<dd><p>Show version.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-formats</samp>’</dt>
|
|
<dd><p>Show available formats.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-codecs</samp>’</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> ‘<samp>-decoders</samp>’</dt>
|
|
<dd><p>Show available decoders.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-encoders</samp>’</dt>
|
|
<dd><p>Show all available encoders.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-bsfs</samp>’</dt>
|
|
<dd><p>Show available bitstream filters.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-protocols</samp>’</dt>
|
|
<dd><p>Show available protocols.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-filters</samp>’</dt>
|
|
<dd><p>Show available libavfilter filters.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-pix_fmts</samp>’</dt>
|
|
<dd><p>Show available pixel formats.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-sample_fmts</samp>’</dt>
|
|
<dd><p>Show available sample formats.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-layouts</samp>’</dt>
|
|
<dd><p>Show channel names and standard channel layouts.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-colors</samp>’</dt>
|
|
<dd><p>Show recognized color names.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-loglevel [repeat+]<var>loglevel</var> | -v [repeat+]<var>loglevel</var></samp>’</dt>
|
|
<dd><p>Set the logging level used by the library.
|
|
Adding "repeat+" indicates that repeated log output should not be compressed
|
|
to the first line and the "Last message repeated n times" line will be
|
|
omitted. "repeat" can also be used alone.
|
|
If "repeat" is used alone, and with no prior loglevel set, the default
|
|
loglevel will be used. If multiple loglevel parameters are given, using
|
|
’repeat’ will not change the loglevel.
|
|
<var>loglevel</var> is a number or a string containing one of the following values:
|
|
</p><dl compact="compact">
|
|
<dt> ‘<samp>quiet</samp>’</dt>
|
|
<dd><p>Show nothing at all; be silent.
|
|
</p></dd>
|
|
<dt> ‘<samp>panic</samp>’</dt>
|
|
<dd><p>Only show fatal errors which could lead the process to crash, such as
|
|
and assert failure. This is not currently used for anything.
|
|
</p></dd>
|
|
<dt> ‘<samp>fatal</samp>’</dt>
|
|
<dd><p>Only show fatal errors. These are errors after which the process absolutely
|
|
cannot continue after.
|
|
</p></dd>
|
|
<dt> ‘<samp>error</samp>’</dt>
|
|
<dd><p>Show all errors, including ones which can be recovered from.
|
|
</p></dd>
|
|
<dt> ‘<samp>warning</samp>’</dt>
|
|
<dd><p>Show all warnings and errors. Any message related to possibly
|
|
incorrect or unexpected events will be shown.
|
|
</p></dd>
|
|
<dt> ‘<samp>info</samp>’</dt>
|
|
<dd><p>Show informative messages during processing. This is in addition to
|
|
warnings and errors. This is the default value.
|
|
</p></dd>
|
|
<dt> ‘<samp>verbose</samp>’</dt>
|
|
<dd><p>Same as <code>info</code>, except more verbose.
|
|
</p></dd>
|
|
<dt> ‘<samp>debug</samp>’</dt>
|
|
<dd><p>Show everything, including debugging information.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<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 <code>NO_COLOR</code>, or can be forced setting
|
|
the environment variable <code>AV_LOG_FORCE_COLOR</code>.
|
|
The use of the environment variable <code>NO_COLOR</code> is deprecated and
|
|
will be dropped in a following FFmpeg version.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-report</samp>’</dt>
|
|
<dd><p>Dump full command line and console 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 verbose</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; options values must be escaped if they
|
|
contain special characters or the options delimiter ’:’ (see the
|
|
“Quoting and escaping” section in the ffmpeg-utils manual). The
|
|
following option is recognized:
|
|
</p><dl compact="compact">
|
|
<dt> ‘<samp>file</samp>’</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>
|
|
</dl>
|
|
|
|
<p>Errors in parsing the environment variable are not fatal, and will not
|
|
appear in the report.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-hide_banner</samp>’</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> ‘<samp>-cpuflags flags (<em>global</em>)</samp>’</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><table><tr><td> </td><td><pre class="example">ffmpeg -cpuflags -sse+mmx ...
|
|
ffmpeg -cpuflags mmx ...
|
|
ffmpeg -cpuflags 0 ...
|
|
</pre></td></tr></table>
|
|
<p>Possible flags for this option are:
|
|
</p><dl compact="compact">
|
|
<dt> ‘<samp>x86</samp>’</dt>
|
|
<dd><dl compact="compact">
|
|
<dt> ‘<samp>mmx</samp>’</dt>
|
|
<dt> ‘<samp>mmxext</samp>’</dt>
|
|
<dt> ‘<samp>sse</samp>’</dt>
|
|
<dt> ‘<samp>sse2</samp>’</dt>
|
|
<dt> ‘<samp>sse2slow</samp>’</dt>
|
|
<dt> ‘<samp>sse3</samp>’</dt>
|
|
<dt> ‘<samp>sse3slow</samp>’</dt>
|
|
<dt> ‘<samp>ssse3</samp>’</dt>
|
|
<dt> ‘<samp>atom</samp>’</dt>
|
|
<dt> ‘<samp>sse4.1</samp>’</dt>
|
|
<dt> ‘<samp>sse4.2</samp>’</dt>
|
|
<dt> ‘<samp>avx</samp>’</dt>
|
|
<dt> ‘<samp>xop</samp>’</dt>
|
|
<dt> ‘<samp>fma4</samp>’</dt>
|
|
<dt> ‘<samp>3dnow</samp>’</dt>
|
|
<dt> ‘<samp>3dnowext</samp>’</dt>
|
|
<dt> ‘<samp>cmov</samp>’</dt>
|
|
</dl>
|
|
</dd>
|
|
<dt> ‘<samp>ARM</samp>’</dt>
|
|
<dd><dl compact="compact">
|
|
<dt> ‘<samp>armv5te</samp>’</dt>
|
|
<dt> ‘<samp>armv6</samp>’</dt>
|
|
<dt> ‘<samp>armv6t2</samp>’</dt>
|
|
<dt> ‘<samp>vfp</samp>’</dt>
|
|
<dt> ‘<samp>vfpv3</samp>’</dt>
|
|
<dt> ‘<samp>neon</samp>’</dt>
|
|
</dl>
|
|
</dd>
|
|
<dt> ‘<samp>PowerPC</samp>’</dt>
|
|
<dd><dl compact="compact">
|
|
<dt> ‘<samp>altivec</samp>’</dt>
|
|
</dl>
|
|
</dd>
|
|
<dt> ‘<samp>Specific Processors</samp>’</dt>
|
|
<dd><dl compact="compact">
|
|
<dt> ‘<samp>pentium2</samp>’</dt>
|
|
<dt> ‘<samp>pentium3</samp>’</dt>
|
|
<dt> ‘<samp>pentium4</samp>’</dt>
|
|
<dt> ‘<samp>k6</samp>’</dt>
|
|
<dt> ‘<samp>k62</samp>’</dt>
|
|
<dt> ‘<samp>athlon</samp>’</dt>
|
|
<dt> ‘<samp>athlonxp</samp>’</dt>
|
|
<dt> ‘<samp>k8</samp>’</dt>
|
|
</dl>
|
|
</dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt> ‘<samp>-opencl_bench</samp>’</dt>
|
|
<dd><p>Benchmark all available OpenCL devices and show the results. This option
|
|
is only available when FFmpeg has been compiled with <code>--enable-opencl</code>.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-opencl_options options (<em>global</em>)</samp>’</dt>
|
|
<dd><p>Set OpenCL environment options. This option is only available when
|
|
FFmpeg has been compiled with <code>--enable-opencl</code>.
|
|
</p>
|
|
<p><var>options</var> must be a list of <var>key</var>=<var>value</var> option pairs
|
|
separated by ’:’. See the “OpenCL Options” section in the
|
|
ffmpeg-utils manual for the list of supported options.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<a name="AVOptions"></a>
|
|
<h2 class="section"><a href="ffmpeg.html#toc-AVOptions">5.3 AVOptions</a></h2>
|
|
|
|
<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> ‘<samp>generic</samp>’</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> ‘<samp>private</samp>’</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><table><tr><td> </td><td><pre class="example">ffmpeg -i input.flac -id3v2_version 3 out.mp3
|
|
</pre></td></tr></table>
|
|
|
|
<p>All codec AVOptions are per-stream, and thus a stream specifier
|
|
should be attached to them.
|
|
</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>
|
|
<h2 class="section"><a href="ffmpeg.html#toc-Main-options">5.4 Main options</a></h2>
|
|
|
|
<dl compact="compact">
|
|
<dt> ‘<samp>-f <var>fmt</var> (<em>input/output</em>)</samp>’</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> ‘<samp>-i <var>filename</var> (<em>input</em>)</samp>’</dt>
|
|
<dd><p>input file name
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-y (<em>global</em>)</samp>’</dt>
|
|
<dd><p>Overwrite output files without asking.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-n (<em>global</em>)</samp>’</dt>
|
|
<dd><p>Do not overwrite output files, and exit immediately if a specified
|
|
output file already exists.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-c[:<var>stream_specifier</var>] <var>codec</var> (<em>input/output,per-stream</em>)</samp>’</dt>
|
|
<dt> ‘<samp>-codec[:<var>stream_specifier</var>] <var>codec</var> (<em>input/output,per-stream</em>)</samp>’</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><table><tr><td> </td><td><pre class="example">ffmpeg -i INPUT -map 0 -c:v libx264 -c:a copy OUTPUT
|
|
</pre></td></tr></table>
|
|
<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><table><tr><td> </td><td><pre class="example">ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT
|
|
</pre></td></tr></table>
|
|
<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> ‘<samp>-t <var>duration</var> (<em>output</em>)</samp>’</dt>
|
|
<dd><p>Stop writing the output after its duration reaches <var>duration</var>.
|
|
<var>duration</var> may be a number in seconds, or in <code>hh:mm:ss[.xxx]</code> form.
|
|
</p>
|
|
<p>-to and -t are mutually exclusive and -t has priority.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-to <var>position</var> (<em>output</em>)</samp>’</dt>
|
|
<dd><p>Stop writing the output at <var>position</var>.
|
|
<var>position</var> may be a number in seconds, or in <code>hh:mm:ss[.xxx]</code> form.
|
|
</p>
|
|
<p>-to and -t are mutually exclusive and -t has priority.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-fs <var>limit_size</var> (<em>output</em>)</samp>’</dt>
|
|
<dd><p>Set the file size limit, expressed in bytes.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-ss <var>position</var> (<em>input/output</em>)</samp>’</dt>
|
|
<dd><p>When used as an input option (before <code>-i</code>), seeks in this input file to
|
|
<var>position</var>. Note the 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 filename), decodes but discards
|
|
input until the timestamps reach <var>position</var>.
|
|
</p>
|
|
<p><var>position</var> may be either in seconds or in <code>hh:mm:ss[.xxx]</code> form.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-itsoffset <var>offset</var> (<em>input</em>)</samp>’</dt>
|
|
<dd><p>Set the input time offset.
|
|
</p>
|
|
<p><var>offset</var> must be a time duration specification,
|
|
see <a href="ffmpeg-utils.html#time-duration-syntax">(ffmpeg-utils)time duration syntax</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> ‘<samp>-timestamp <var>date</var> (<em>output</em>)</samp>’</dt>
|
|
<dd><p>Set the recording timestamp in the container.
|
|
</p>
|
|
<p><var>date</var> must be a time duration specification,
|
|
see <a href="ffmpeg-utils.html#date-syntax">(ffmpeg-utils)date syntax</a>.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-metadata[:metadata_specifier] <var>key</var>=<var>value</var> (<em>output,per-metadata</em>)</samp>’</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 or chapters. 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><table><tr><td> </td><td><pre class="example">ffmpeg -i in.avi -metadata title="my title" out.flv
|
|
</pre></td></tr></table>
|
|
|
|
<p>To set the language of the first audio stream:
|
|
</p><table><tr><td> </td><td><pre class="example">ffmpeg -i INPUT -metadata:s:a:1 language=eng OUTPUT
|
|
</pre></td></tr></table>
|
|
|
|
</dd>
|
|
<dt> ‘<samp>-target <var>type</var> (<em>output</em>)</samp>’</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>
|
|
<table><tr><td> </td><td><pre class="example">ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
|
|
</pre></td></tr></table>
|
|
|
|
<p>Nevertheless you can specify additional options as long as you know
|
|
they do not conflict with the standard, as in:
|
|
</p>
|
|
<table><tr><td> </td><td><pre class="example">ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
|
|
</pre></td></tr></table>
|
|
|
|
</dd>
|
|
<dt> ‘<samp>-dframes <var>number</var> (<em>output</em>)</samp>’</dt>
|
|
<dd><p>Set the number of data frames to record. This is an alias for <code>-frames:d</code>.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-frames[:<var>stream_specifier</var>] <var>framecount</var> (<em>output,per-stream</em>)</samp>’</dt>
|
|
<dd><p>Stop writing to the stream after <var>framecount</var> frames.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-q[:<var>stream_specifier</var>] <var>q</var> (<em>output,per-stream</em>)</samp>’</dt>
|
|
<dt> ‘<samp>-qscale[:<var>stream_specifier</var>] <var>q</var> (<em>output,per-stream</em>)</samp>’</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>
|
|
<p><a name="filter_005foption"></a>
|
|
</p></dd>
|
|
<dt> ‘<samp>-filter[:<var>stream_specifier</var>] <var>filtergraph</var> (<em>output,per-stream</em>)</samp>’</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> ‘<samp>-filter_script[:<var>stream_specifier</var>] <var>filename</var> (<em>output,per-stream</em>)</samp>’</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> ‘<samp>-pre[:<var>stream_specifier</var>] <var>preset_name</var> (<em>output,per-stream</em>)</samp>’</dt>
|
|
<dd><p>Specify the preset for matching stream(s).
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-stats (<em>global</em>)</samp>’</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> ‘<samp>-progress <var>url</var> (<em>global</em>)</samp>’</dt>
|
|
<dd><p>Send program-friendly progress information to <var>url</var>.
|
|
</p>
|
|
<p>Progress information is written approximately every second 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>
|
|
</dd>
|
|
<dt> ‘<samp>-stdin</samp>’</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> ‘<samp>-debug_ts (<em>global</em>)</samp>’</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> ‘<samp>-attach <var>filename</var> (<em>output</em>)</samp>’</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><table><tr><td> </td><td><pre class="example">ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv
|
|
</pre></td></tr></table>
|
|
<p>(assuming that the attachment stream will be third in the output file).
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-dump_attachment[:<var>stream_specifier</var>] <var>filename</var> (<em>input,per-stream</em>)</samp>’</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><table><tr><td> </td><td><pre class="example">ffmpeg -dump_attachment:t:0 out.ttf -i INPUT
|
|
</pre></td></tr></table>
|
|
<p>To extract all attachments to files determined by the <code>filename</code> tag:
|
|
</p><table><tr><td> </td><td><pre class="example">ffmpeg -dump_attachment:t "" -i INPUT
|
|
</pre></td></tr></table>
|
|
|
|
<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>
|
|
<h2 class="section"><a href="ffmpeg.html#toc-Video-Options">5.5 Video Options</a></h2>
|
|
|
|
<dl compact="compact">
|
|
<dt> ‘<samp>-vframes <var>number</var> (<em>output</em>)</samp>’</dt>
|
|
<dd><p>Set the number of video frames to record. This is an alias for <code>-frames:v</code>.
|
|
</p></dd>
|
|
<dt> ‘<samp>-r[:<var>stream_specifier</var>] <var>fps</var> (<em>input/output,per-stream</em>)</samp>’</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>.
|
|
</p>
|
|
<p>As an output option, duplicate or drop input frames to achieve constant output
|
|
frame rate <var>fps</var>.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-s[:<var>stream_specifier</var>] <var>size</var> (<em>input/output,per-stream</em>)</samp>’</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> ‘<samp>-aspect[:<var>stream_specifier</var>] <var>aspect</var> (<em>output,per-stream</em>)</samp>’</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> ‘<samp>-vn (<em>output</em>)</samp>’</dt>
|
|
<dd><p>Disable video recording.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-vcodec <var>codec</var> (<em>output</em>)</samp>’</dt>
|
|
<dd><p>Set the video codec. This is an alias for <code>-codec:v</code>.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-pass[:<var>stream_specifier</var>] <var>n</var> (<em>output,per-stream</em>)</samp>’</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><table><tr><td> </td><td><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></td></tr></table>
|
|
|
|
</dd>
|
|
<dt> ‘<samp>-passlogfile[:<var>stream_specifier</var>] <var>prefix</var> (<em>output,per-stream</em>)</samp>’</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
|
|
‘<tt>PREFIX-N.log</tt>’, where N is a number specific to the output
|
|
stream
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-vf <var>filtergraph</var> (<em>output</em>)</samp>’</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>
|
|
</dl>
|
|
|
|
<a name="Advanced-Video-Options"></a>
|
|
<h2 class="section"><a href="ffmpeg.html#toc-Advanced-Video-Options">5.6 Advanced Video Options</a></h2>
|
|
|
|
<dl compact="compact">
|
|
<dt> ‘<samp>-pix_fmt[:<var>stream_specifier</var>] <var>format</var> (<em>input/output,per-stream</em>)</samp>’</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> ‘<samp>-sws_flags <var>flags</var> (<em>input/output</em>)</samp>’</dt>
|
|
<dd><p>Set SwScaler flags.
|
|
</p></dd>
|
|
<dt> ‘<samp>-vdt <var>n</var></samp>’</dt>
|
|
<dd><p>Discard threshold.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-rc_override[:<var>stream_specifier</var>] <var>override</var> (<em>output,per-stream</em>)</samp>’</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> ‘<samp>-ilme</samp>’</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 with
|
|
‘<samp>-deinterlace</samp>’, but deinterlacing introduces losses.
|
|
</p></dd>
|
|
<dt> ‘<samp>-psnr</samp>’</dt>
|
|
<dd><p>Calculate PSNR of compressed frames.
|
|
</p></dd>
|
|
<dt> ‘<samp>-vstats</samp>’</dt>
|
|
<dd><p>Dump video coding statistics to ‘<tt>vstats_HHMMSS.log</tt>’.
|
|
</p></dd>
|
|
<dt> ‘<samp>-vstats_file <var>file</var></samp>’</dt>
|
|
<dd><p>Dump video coding statistics to <var>file</var>.
|
|
</p></dd>
|
|
<dt> ‘<samp>-top[:<var>stream_specifier</var>] <var>n</var> (<em>output,per-stream</em>)</samp>’</dt>
|
|
<dd><p>top=1/bottom=0/auto=-1 field first
|
|
</p></dd>
|
|
<dt> ‘<samp>-dc <var>precision</var></samp>’</dt>
|
|
<dd><p>Intra_dc_precision.
|
|
</p></dd>
|
|
<dt> ‘<samp>-vtag <var>fourcc/tag</var> (<em>output</em>)</samp>’</dt>
|
|
<dd><p>Force video tag/fourcc. This is an alias for <code>-tag:v</code>.
|
|
</p></dd>
|
|
<dt> ‘<samp>-qphist (<em>global</em>)</samp>’</dt>
|
|
<dd><p>Show QP histogram
|
|
</p></dd>
|
|
<dt> ‘<samp>-vbsf <var>bitstream_filter</var></samp>’</dt>
|
|
<dd><p>Deprecated see -bsf
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-force_key_frames[:<var>stream_specifier</var>] <var>time</var>[,<var>time</var>...] (<em>output,per-stream</em>)</samp>’</dt>
|
|
<dt> ‘<samp>-force_key_frames[:<var>stream_specifier</var>] expr:<var>expr</var> (<em>output,per-stream</em>)</samp>’</dt>
|
|
<dd><p>Force key frames at the specified timestamps, more precisely at the first
|
|
frames after each specified time.
|
|
</p>
|
|
<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>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><table><tr><td> </td><td><pre class="example">-force_key_frames 0:05:00,chapters-0.1
|
|
</pre></td></tr></table>
|
|
|
|
<p>The expression in <var>expr</var> can contain the following constants:
|
|
</p><dl compact="compact">
|
|
<dt> ‘<samp>n</samp>’</dt>
|
|
<dd><p>the number of current processed frame, starting from 0
|
|
</p></dd>
|
|
<dt> ‘<samp>n_forced</samp>’</dt>
|
|
<dd><p>the number of forced frames
|
|
</p></dd>
|
|
<dt> ‘<samp>prev_forced_n</samp>’</dt>
|
|
<dd><p>the number of the previous forced frame, it is <code>NAN</code> when no
|
|
keyframe was forced yet
|
|
</p></dd>
|
|
<dt> ‘<samp>prev_forced_t</samp>’</dt>
|
|
<dd><p>the time of the previous forced frame, it is <code>NAN</code> when no
|
|
keyframe was forced yet
|
|
</p></dd>
|
|
<dt> ‘<samp>t</samp>’</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><table><tr><td> </td><td><pre class="example">-force_key_frames expr:gte(t,n_forced*5)
|
|
</pre></td></tr></table>
|
|
|
|
<p>To force a key frame 5 seconds after the time of the last forced one,
|
|
starting from second 13:
|
|
</p><table><tr><td> </td><td><pre class="example">-force_key_frames expr:if(isnan(prev_forced_t),gte(t,13),gte(t,prev_forced_t+5))
|
|
</pre></td></tr></table>
|
|
|
|
<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> ‘<samp>-copyinkf[:<var>stream_specifier</var>] (<em>output,per-stream</em>)</samp>’</dt>
|
|
<dd><p>When doing stream copy, copy also non-key frames found at the
|
|
beginning.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-hwaccel[:<var>stream_specifier</var>] <var>hwaccel</var> (<em>input,per-stream</em>)</samp>’</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> ‘<samp>none</samp>’</dt>
|
|
<dd><p>Do not use any hardware acceleration (the default).
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>auto</samp>’</dt>
|
|
<dd><p>Automatically select the hardware acceleration method.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>vdpau</samp>’</dt>
|
|
<dd><p>Use VDPAU (Video Decode and Presentation API for Unix) hardware acceleration.
|
|
</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> ‘<samp>-hwaccel_device[:<var>stream_specifier</var>] <var>hwaccel_device</var> (<em>input,per-stream</em>)</samp>’</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. Its exact meaning depends on the specific hardware acceleration
|
|
method chosen.
|
|
</p>
|
|
<dl compact="compact">
|
|
<dt> ‘<samp>vdpau</samp>’</dt>
|
|
<dd><p>For VDPAU, this option specifies the X11 display/screen to use. If this option
|
|
is not specified, the value of the <var>DISPLAY</var> environment variable is used
|
|
</p></dd>
|
|
</dl>
|
|
</dd>
|
|
</dl>
|
|
|
|
<a name="Audio-Options"></a>
|
|
<h2 class="section"><a href="ffmpeg.html#toc-Audio-Options">5.7 Audio Options</a></h2>
|
|
|
|
<dl compact="compact">
|
|
<dt> ‘<samp>-aframes <var>number</var> (<em>output</em>)</samp>’</dt>
|
|
<dd><p>Set the number of audio frames to record. This is an alias for <code>-frames:a</code>.
|
|
</p></dd>
|
|
<dt> ‘<samp>-ar[:<var>stream_specifier</var>] <var>freq</var> (<em>input/output,per-stream</em>)</samp>’</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> ‘<samp>-aq <var>q</var> (<em>output</em>)</samp>’</dt>
|
|
<dd><p>Set the audio quality (codec-specific, VBR). This is an alias for -q:a.
|
|
</p></dd>
|
|
<dt> ‘<samp>-ac[:<var>stream_specifier</var>] <var>channels</var> (<em>input/output,per-stream</em>)</samp>’</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> ‘<samp>-an (<em>output</em>)</samp>’</dt>
|
|
<dd><p>Disable audio recording.
|
|
</p></dd>
|
|
<dt> ‘<samp>-acodec <var>codec</var> (<em>input/output</em>)</samp>’</dt>
|
|
<dd><p>Set the audio codec. This is an alias for <code>-codec:a</code>.
|
|
</p></dd>
|
|
<dt> ‘<samp>-sample_fmt[:<var>stream_specifier</var>] <var>sample_fmt</var> (<em>output,per-stream</em>)</samp>’</dt>
|
|
<dd><p>Set the audio sample format. Use <code>-sample_fmts</code> to get a list
|
|
of supported sample formats.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-af <var>filtergraph</var> (<em>output</em>)</samp>’</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_003a"></a>
|
|
<h2 class="section"><a href="ffmpeg.html#toc-Advanced-Audio-options_003a">5.8 Advanced Audio options:</a></h2>
|
|
|
|
<dl compact="compact">
|
|
<dt> ‘<samp>-atag <var>fourcc/tag</var> (<em>output</em>)</samp>’</dt>
|
|
<dd><p>Force audio tag/fourcc. This is an alias for <code>-tag:a</code>.
|
|
</p></dd>
|
|
<dt> ‘<samp>-absf <var>bitstream_filter</var></samp>’</dt>
|
|
<dd><p>Deprecated, see -bsf
|
|
</p></dd>
|
|
<dt> ‘<samp>-guess_layout_max <var>channels</var> (<em>input,per-stream</em>)</samp>’</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_003a"></a>
|
|
<h2 class="section"><a href="ffmpeg.html#toc-Subtitle-options_003a">5.9 Subtitle options:</a></h2>
|
|
|
|
<dl compact="compact">
|
|
<dt> ‘<samp>-scodec <var>codec</var> (<em>input/output</em>)</samp>’</dt>
|
|
<dd><p>Set the subtitle codec. This is an alias for <code>-codec:s</code>.
|
|
</p></dd>
|
|
<dt> ‘<samp>-sn (<em>output</em>)</samp>’</dt>
|
|
<dd><p>Disable subtitle recording.
|
|
</p></dd>
|
|
<dt> ‘<samp>-sbsf <var>bitstream_filter</var></samp>’</dt>
|
|
<dd><p>Deprecated, see -bsf
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<a name="Advanced-Subtitle-options_003a"></a>
|
|
<h2 class="section"><a href="ffmpeg.html#toc-Advanced-Subtitle-options_003a">5.10 Advanced Subtitle options:</a></h2>
|
|
|
|
<dl compact="compact">
|
|
<dt> ‘<samp>-fix_sub_duration</samp>’</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> ‘<samp>-canvas_size <var>size</var></samp>’</dt>
|
|
<dd><p>Set the size of the canvas used to render subtitles.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
<a name="Advanced-options"></a>
|
|
<h2 class="section"><a href="ffmpeg.html#toc-Advanced-options">5.11 Advanced options</a></h2>
|
|
|
|
<dl compact="compact">
|
|
<dt> ‘<samp>-map [-]<var>input_file_id</var>[:<var>stream_specifier</var>][,<var>sync_file_id</var>[:<var>stream_specifier</var>]] | <var>[linklabel]</var> (<em>output</em>)</samp>’</dt>
|
|
<dd>
|
|
<p>Designate one or more input streams as a source for the output file. Each input
|
|
stream is identified by the input file index <var>input_file_id</var> and
|
|
the input stream index <var>input_stream_id</var> within the input
|
|
file. Both indices start at 0. If specified,
|
|
<var>sync_file_id</var>:<var>stream_specifier</var> sets which input stream
|
|
is used as a presentation sync reference.
|
|
</p>
|
|
<p>The first <code>-map</code> option on the command line specifies the
|
|
source for output stream 0, the second <code>-map</code> option specifies
|
|
the source for output stream 1, etc.
|
|
</p>
|
|
<p>A <code>-</code> character before the stream identifier creates a "negative" mapping.
|
|
It disables matching streams from already created mappings.
|
|
</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>For example, to map ALL streams from the first input file to output
|
|
</p><table><tr><td> </td><td><pre class="example">ffmpeg -i INPUT -map 0 output
|
|
</pre></td></tr></table>
|
|
|
|
<p>For example, if you have two audio streams in the first input file,
|
|
these streams are identified by "0:0" and "0:1". You can use
|
|
<code>-map</code> to select which streams to place in an output file. For
|
|
example:
|
|
</p><table><tr><td> </td><td><pre class="example">ffmpeg -i INPUT -map 0:1 out.wav
|
|
</pre></td></tr></table>
|
|
<p>will map the input stream in ‘<tt>INPUT</tt>’ identified by "0:1" to
|
|
the (single) output stream in ‘<tt>out.wav</tt>’.
|
|
</p>
|
|
<p>For example, to select the stream with index 2 from input file
|
|
‘<tt>a.mov</tt>’ (specified by the identifier "0:2"), and stream with
|
|
index 6 from input ‘<tt>b.mov</tt>’ (specified by the identifier "1:6"),
|
|
and copy them to the output file ‘<tt>out.mov</tt>’:
|
|
</p><table><tr><td> </td><td><pre class="example">ffmpeg -i a.mov -i b.mov -c copy -map 0:2 -map 1:6 out.mov
|
|
</pre></td></tr></table>
|
|
|
|
<p>To select all video and the third audio stream from an input file:
|
|
</p><table><tr><td> </td><td><pre class="example">ffmpeg -i INPUT -map 0:v -map 0:a:2 OUTPUT
|
|
</pre></td></tr></table>
|
|
|
|
<p>To map all the streams except the second audio, use negative mappings
|
|
</p><table><tr><td> </td><td><pre class="example">ffmpeg -i INPUT -map 0 -map -0:a:1 OUTPUT
|
|
</pre></td></tr></table>
|
|
|
|
<p>Note that using this option disables the default mappings for this output file.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<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>’</dt>
|
|
<dd><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>For example, assuming <var>INPUT</var> is a stereo audio file, you can switch the
|
|
two audio channels with the following command:
|
|
</p><table><tr><td> </td><td><pre class="example">ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT
|
|
</pre></td></tr></table>
|
|
|
|
<p>If you want to mute the first channel and keep the second:
|
|
</p><table><tr><td> </td><td><pre class="example">ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT
|
|
</pre></td></tr></table>
|
|
|
|
<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><table><tr><td> </td><td><pre class="example">ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1
|
|
</pre></td></tr></table>
|
|
|
|
<p>The following example splits the channels of a stereo input into two separate
|
|
streams, which are put into the same output file:
|
|
</p><table><tr><td> </td><td><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></td></tr></table>
|
|
|
|
<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 ‘<tt>input.mkv</tt>’) with 2
|
|
mono audio streams into one single stereo channel audio stream (and keep the
|
|
video stream), you can use the following command:
|
|
</p><table><tr><td> </td><td><pre class="example">ffmpeg -i input.mkv -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le -c:v copy output.mkv
|
|
</pre></td></tr></table>
|
|
|
|
</dd>
|
|
<dt> ‘<samp>-map_metadata[:<var>metadata_spec_out</var>] <var>infile</var>[:<var>metadata_spec_in</var>] (<em>output,per-metadata</em>)</samp>’</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> ‘<samp><var>g</var></samp>’</dt>
|
|
<dd><p>global metadata, i.e. metadata that applies to the whole file
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp><var>s</var>[:<var>stream_spec</var>]</samp>’</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> ‘<samp><var>c</var>:<var>chapter_index</var></samp>’</dt>
|
|
<dd><p>per-chapter metadata. <var>chapter_index</var> is the zero-based chapter index.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp><var>p</var>:<var>program_index</var></samp>’</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><table><tr><td> </td><td><pre class="example">ffmpeg -i in.ogg -map_metadata 0:s:0 out.mp3
|
|
</pre></td></tr></table>
|
|
|
|
<p>To do the reverse, i.e. copy global metadata to all audio streams:
|
|
</p><table><tr><td> </td><td><pre class="example">ffmpeg -i in.mkv -map_metadata:s:a 0:g out.mkv
|
|
</pre></td></tr></table>
|
|
<p>Note that simple <code>0</code> would work as well in this example, since global
|
|
metadata is assumed by default.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-map_chapters <var>input_file_index</var> (<em>output</em>)</samp>’</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> ‘<samp>-benchmark (<em>global</em>)</samp>’</dt>
|
|
<dd><p>Show benchmarking information at the end of an encode.
|
|
Shows CPU time used and maximum memory consumption.
|
|
Maximum memory consumption is not supported on all systems,
|
|
it will usually display as 0 if not supported.
|
|
</p></dd>
|
|
<dt> ‘<samp>-benchmark_all (<em>global</em>)</samp>’</dt>
|
|
<dd><p>Show benchmarking information during the encode.
|
|
Shows CPU time used in various steps (audio/video encode/decode).
|
|
</p></dd>
|
|
<dt> ‘<samp>-timelimit <var>duration</var> (<em>global</em>)</samp>’</dt>
|
|
<dd><p>Exit after ffmpeg has been running for <var>duration</var> seconds.
|
|
</p></dd>
|
|
<dt> ‘<samp>-dump (<em>global</em>)</samp>’</dt>
|
|
<dd><p>Dump each input packet to stderr.
|
|
</p></dd>
|
|
<dt> ‘<samp>-hex (<em>global</em>)</samp>’</dt>
|
|
<dd><p>When dumping packets, also dump the payload.
|
|
</p></dd>
|
|
<dt> ‘<samp>-re (<em>input</em>)</samp>’</dt>
|
|
<dd><p>Read input at native frame rate. Mainly used to simulate a grab device.
|
|
or live input stream (e.g. when reading from a file). Should not be used
|
|
with actual grab devices or live input streams (where it can cause packet
|
|
loss).
|
|
By default <code>ffmpeg</code> attempts to read the input(s) as fast as possible.
|
|
This option will slow down the reading of the input(s) to the native frame rate
|
|
of the input(s). It is useful for real-time output (e.g. live streaming).
|
|
</p></dd>
|
|
<dt> ‘<samp>-loop_input</samp>’</dt>
|
|
<dd><p>Loop over the input stream. Currently it works only for image
|
|
streams. This option is used for automatic FFserver testing.
|
|
This option is deprecated, use -loop 1.
|
|
</p></dd>
|
|
<dt> ‘<samp>-loop_output <var>number_of_times</var></samp>’</dt>
|
|
<dd><p>Repeatedly loop output for formats that support looping such as animated GIF
|
|
(0 will loop the output infinitely).
|
|
This option is deprecated, use -loop.
|
|
</p></dd>
|
|
<dt> ‘<samp>-vsync <var>parameter</var></samp>’</dt>
|
|
<dd><p>Video sync method.
|
|
For compatibility reasons old values can be specified as numbers.
|
|
Newly added values will have to be specified as strings always.
|
|
</p>
|
|
<dl compact="compact">
|
|
<dt> ‘<samp>0, passthrough</samp>’</dt>
|
|
<dd><p>Each frame is passed with its timestamp from the demuxer to the muxer.
|
|
</p></dd>
|
|
<dt> ‘<samp>1, cfr</samp>’</dt>
|
|
<dd><p>Frames will be duplicated and dropped to achieve exactly the requested
|
|
constant frame rate.
|
|
</p></dd>
|
|
<dt> ‘<samp>2, vfr</samp>’</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> ‘<samp>drop</samp>’</dt>
|
|
<dd><p>As passthrough but destroys all timestamps, making the muxer generate
|
|
fresh timestamps based on frame-rate.
|
|
</p></dd>
|
|
<dt> ‘<samp>-1, auto</samp>’</dt>
|
|
<dd><p>Chooses between 1 and 2 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> ‘<samp>-async <var>samples_per_second</var></samp>’</dt>
|
|
<dd><p>Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
|
|
the parameter is the maximum samples per second by which the audio is changed.
|
|
-async 1 is a special case where only the start of the audio stream is corrected
|
|
without any later correction.
|
|
</p>
|
|
<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>This option has been deprecated. Use the <code>aresample</code> audio filter instead.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-copyts</samp>’</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> ‘<samp>-copytb <var>mode</var></samp>’</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> ‘<samp>1</samp>’</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> ‘<samp>0</samp>’</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> ‘<samp>-1</samp>’</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> ‘<samp>-shortest (<em>output</em>)</samp>’</dt>
|
|
<dd><p>Finish encoding when the shortest input stream ends.
|
|
</p></dd>
|
|
<dt> ‘<samp>-dts_delta_threshold</samp>’</dt>
|
|
<dd><p>Timestamp discontinuity delta threshold.
|
|
</p></dd>
|
|
<dt> ‘<samp>-muxdelay <var>seconds</var> (<em>input</em>)</samp>’</dt>
|
|
<dd><p>Set the maximum demux-decode delay.
|
|
</p></dd>
|
|
<dt> ‘<samp>-muxpreload <var>seconds</var> (<em>input</em>)</samp>’</dt>
|
|
<dd><p>Set the initial demux-decode delay.
|
|
</p></dd>
|
|
<dt> ‘<samp>-streamid <var>output-stream-index</var>:<var>new-value</var> (<em>output</em>)</samp>’</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><table><tr><td> </td><td><pre class="example">ffmpeg -i infile -streamid 0:33 -streamid 1:36 out.ts
|
|
</pre></td></tr></table>
|
|
|
|
</dd>
|
|
<dt> ‘<samp>-bsf[:<var>stream_specifier</var>] <var>bitstream_filters</var> (<em>output,per-stream</em>)</samp>’</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><table><tr><td> </td><td><pre class="example">ffmpeg -i h264.mp4 -c:v copy -bsf:v h264_mp4toannexb -an out.h264
|
|
</pre></td></tr></table>
|
|
<table><tr><td> </td><td><pre class="example">ffmpeg -i file.mov -an -vn -bsf:s mov2textsub -c:s copy -f rawvideo sub.txt
|
|
</pre></td></tr></table>
|
|
|
|
</dd>
|
|
<dt> ‘<samp>-tag[:<var>stream_specifier</var>] <var>codec_tag</var> (<em>input/output,per-stream</em>)</samp>’</dt>
|
|
<dd><p>Force a tag/fourcc for matching streams.
|
|
</p>
|
|
</dd>
|
|
<dt> ‘<samp>-timecode <var>hh</var>:<var>mm</var>:<var>ss</var>SEP<var>ff</var></samp>’</dt>
|
|
<dd><p>Specify Timecode for writing. <var>SEP</var> is ’:’ for non drop timecode and ’;’
|
|
(or ’.’) for drop.
|
|
</p><table><tr><td> </td><td><pre class="example">ffmpeg -i input.mpg -timecode 01:02:03.04 -r 30000/1001 -s ntsc output.mpg
|
|
</pre></td></tr></table>
|
|
|
|
<p><a name="filter_005fcomplex_005foption"></a>
|
|
</p></dd>
|
|
<dt> ‘<samp>-filter_complex <var>filtergraph</var> (<em>global</em>)</samp>’</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><table><tr><td> </td><td><pre class="example">ffmpeg -i video.mkv -i image.png -filter_complex '[0:v][1:v]overlay[out]' -map
|
|
'[out]' out.mkv
|
|
</pre></td></tr></table>
|
|
<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><table><tr><td> </td><td><pre class="example">ffmpeg -i video.mkv -i image.png -filter_complex 'overlay[out]' -map
|
|
'[out]' out.mkv
|
|
</pre></td></tr></table>
|
|
|
|
<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><table><tr><td> </td><td><pre class="example">ffmpeg -i video.mkv -i image.png -filter_complex 'overlay' out.mkv
|
|
</pre></td></tr></table>
|
|
|
|
<p>To generate 5 seconds of pure red video using lavfi <code>color</code> source:
|
|
</p><table><tr><td> </td><td><pre class="example">ffmpeg -filter_complex 'color=c=red' -t 5 out.mkv
|
|
</pre></td></tr></table>
|
|
|
|
</dd>
|
|
<dt> ‘<samp>-lavfi <var>filtergraph</var> (<em>global</em>)</samp>’</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> ‘<samp>-filter_complex_script <var>filename</var> (<em>global</em>)</samp>’</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> ‘<samp>-accurate_seek (<em>input</em>)</samp>’</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> ‘<samp>-override_ffserver (<em>global</em>)</samp>’</dt>
|
|
<dd><p>Overrides the input specifications from <code>ffserver</code>. Using this
|
|
option you can map any input stream to <code>ffserver</code> and control
|
|
many aspects of the encoding from <code>ffmpeg</code>. Without this
|
|
option <code>ffmpeg</code> will transmit to <code>ffserver</code> what is
|
|
requested by <code>ffserver</code>.
|
|
</p>
|
|
<p>The option is intended for cases where features are needed that cannot be
|
|
specified to <code>ffserver</code> but can be to <code>ffmpeg</code>.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
<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><table><tr><td> </td><td><pre class="example">ffmpeg -i input.ts -filter_complex \
|
|
'[#0x2ef] setpts=PTS+1/TB [sub] ; [#0x2d0] [sub] overlay' \
|
|
-sn -map '#0x2dc' output.mkv
|
|
</pre></td></tr></table>
|
|
<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>
|
|
<a name="Preset-files"></a>
|
|
<h2 class="section"><a href="ffmpeg.html#toc-Preset-files">5.12 Preset files</a></h2>
|
|
<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 ‘<tt>presets</tt>’ directory in the FFmpeg source tree for examples.
|
|
</p>
|
|
<p>Preset 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 ‘<tt>$FFMPEG_DATADIR</tt>’ (if set), and ‘<tt>$HOME/.ffmpeg</tt>’, and in
|
|
the datadir defined at configuration time (usually ‘<tt>PREFIX/share/ffmpeg</tt>’)
|
|
or in a ‘<tt>ffpresets</tt>’ 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 ‘<tt>libvpx-1080p.ffpreset</tt>’.
|
|
</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 ‘<tt>libvpx-1080p.ffpreset</tt>’.
|
|
</p>
|
|
<a name="Tips"></a>
|
|
<h1 class="chapter"><a href="ffmpeg.html#toc-Tips">6. Tips</a></h1>
|
|
|
|
<ul>
|
|
<li>
|
|
For streaming at very low bitrates, use a low frame rate
|
|
and a small GOP size. This is especially true for RealVideo where
|
|
the Linux player does not seem to be very fast, so it can miss
|
|
frames. An example is:
|
|
|
|
<table><tr><td> </td><td><pre class="example">ffmpeg -g 3 -r 3 -t 10 -b:v 50k -s qcif -f rv10 /tmp/b.rm
|
|
</pre></td></tr></table>
|
|
|
|
</li><li>
|
|
The parameter ’q’ which is displayed while encoding is the current
|
|
quantizer. The value 1 indicates that a very good quality could
|
|
be achieved. The value 31 indicates the worst quality. If q=31 appears
|
|
too often, it means that the encoder cannot compress enough to meet
|
|
your bitrate. You must either increase the bitrate, decrease the
|
|
frame rate or decrease the frame size.
|
|
|
|
</li><li>
|
|
If your computer is not fast enough, you can speed up the
|
|
compression at the expense of the compression ratio. You can use
|
|
’-me zero’ to speed up motion estimation, and ’-g 0’ to disable
|
|
motion estimation completely (you have only I-frames, which means it
|
|
is about as good as JPEG compression).
|
|
|
|
</li><li>
|
|
To have very low audio bitrates, reduce the sampling frequency
|
|
(down to 22050 Hz for MPEG audio, 22050 or 11025 for AC-3).
|
|
|
|
</li><li>
|
|
To have a constant quality (but a variable bitrate), use the option
|
|
’-qscale n’ when ’n’ is between 1 (excellent quality) and 31 (worst
|
|
quality).
|
|
|
|
</li></ul>
|
|
|
|
<a name="Examples"></a>
|
|
<h1 class="chapter"><a href="ffmpeg.html#toc-Examples">7. Examples</a></h1>
|
|
|
|
<a name="Preset-files-1"></a>
|
|
<h2 class="section"><a href="ffmpeg.html#toc-Preset-files-1">7.1 Preset files</a></h2>
|
|
|
|
<p>A preset file contains a sequence of <var>option=value</var> pairs, one for
|
|
each line, specifying a sequence of options which can be specified also on
|
|
the command line. Lines starting with the hash (’#’) character are ignored and
|
|
are used to provide comments. Empty lines are also ignored. Check the
|
|
‘<tt>presets</tt>’ directory in the FFmpeg source tree for examples.
|
|
</p>
|
|
<p>Preset files are specified with the <code>pre</code> option, this option takes a
|
|
preset name as input. FFmpeg searches for a file named <var>preset_name</var>.avpreset in
|
|
the directories ‘<tt>$AVCONV_DATADIR</tt>’ (if set), and ‘<tt>$HOME/.ffmpeg</tt>’, and in
|
|
the data directory defined at configuration time (usually ‘<tt>$PREFIX/share/ffmpeg</tt>’)
|
|
in that order. For example, if the argument is <code>libx264-max</code>, it will
|
|
search for the file ‘<tt>libx264-max.avpreset</tt>’.
|
|
</p>
|
|
<a name="Video-and-Audio-grabbing"></a>
|
|
<h2 class="section"><a href="ffmpeg.html#toc-Video-and-Audio-grabbing">7.2 Video and Audio grabbing</a></h2>
|
|
|
|
<p>If you specify the input format and device then ffmpeg can grab video
|
|
and audio directly.
|
|
</p>
|
|
<table><tr><td> </td><td><pre class="example">ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
|
|
</pre></td></tr></table>
|
|
|
|
<p>Or with an ALSA audio source (mono input, card id 1) instead of OSS:
|
|
</p><table><tr><td> </td><td><pre class="example">ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg
|
|
</pre></td></tr></table>
|
|
|
|
<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>
|
|
<h2 class="section"><a href="ffmpeg.html#toc-X11-grabbing">7.3 X11 grabbing</a></h2>
|
|
|
|
<p>Grab the X11 display with ffmpeg via
|
|
</p>
|
|
<table><tr><td> </td><td><pre class="example">ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0 /tmp/out.mpg
|
|
</pre></td></tr></table>
|
|
|
|
<p>0.0 is display.screen number of your X11 server, same as
|
|
the DISPLAY environment variable.
|
|
</p>
|
|
<table><tr><td> </td><td><pre class="example">ffmpeg -f x11grab -video_size cif -framerate 25 -i :0.0+10,20 /tmp/out.mpg
|
|
</pre></td></tr></table>
|
|
|
|
<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>
|
|
<h2 class="section"><a href="ffmpeg.html#toc-Video-and-Audio-file-format-conversion">7.4 Video and Audio file format conversion</a></h2>
|
|
|
|
<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:
|
|
|
|
<table><tr><td> </td><td><pre class="example">ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
|
|
</pre></td></tr></table>
|
|
|
|
<p>It will use the files:
|
|
</p><table><tr><td> </td><td><pre class="example">/tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
|
|
/tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
|
|
</pre></td></tr></table>
|
|
|
|
<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:
|
|
|
|
<table><tr><td> </td><td><pre class="example">ffmpeg -i /tmp/test.yuv /tmp/out.avi
|
|
</pre></td></tr></table>
|
|
|
|
<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:
|
|
|
|
<table><tr><td> </td><td><pre class="example">ffmpeg -i mydivx.avi hugefile.yuv
|
|
</pre></td></tr></table>
|
|
|
|
</li><li>
|
|
You can set several input files and output files:
|
|
|
|
<table><tr><td> </td><td><pre class="example">ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
|
|
</pre></td></tr></table>
|
|
|
|
<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:
|
|
|
|
<table><tr><td> </td><td><pre class="example">ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
|
|
</pre></td></tr></table>
|
|
|
|
<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:
|
|
|
|
<table><tr><td> </td><td><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></td></tr></table>
|
|
|
|
<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:
|
|
|
|
<table><tr><td> </td><td><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></td></tr></table>
|
|
|
|
<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 -formats</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><table><tr><td> </td><td><pre class="example">ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
|
|
</pre></td></tr></table>
|
|
|
|
<p>This will extract one video frame per second from the video and will
|
|
output them in files named ‘<tt>foo-001.jpeg</tt>’, ‘<tt>foo-002.jpeg</tt>’,
|
|
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 -vframes or -t 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><table><tr><td> </td><td><pre class="example">ffmpeg -f image2 -i foo-%03d.jpeg -r 12 -s WxH foo.avi
|
|
</pre></td></tr></table>
|
|
|
|
<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><table><tr><td> </td><td><pre class="example">ffmpeg -f image2 -pattern_type glob -i 'foo-*.jpeg' -r 12 -s WxH foo.avi
|
|
</pre></td></tr></table>
|
|
|
|
</li><li>
|
|
You can put many streams of the same type in the output:
|
|
|
|
<table><tr><td> </td><td><pre class="example">ffmpeg -i test1.avi -i test2.avi -map 0:3 -map 0:2 -map 0:1 -map 0:0 -c copy test12.nut
|
|
</pre></td></tr></table>
|
|
|
|
<p>The resulting output file ‘<tt>test12.avi</tt>’ will contain first four streams from
|
|
the input file in reverse order.
|
|
</p>
|
|
</li><li>
|
|
To force CBR video output:
|
|
<table><tr><td> </td><td><pre class="example">ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
|
|
</pre></td></tr></table>
|
|
|
|
</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:
|
|
<table><tr><td> </td><td><pre class="example">ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
|
|
</pre></td></tr></table>
|
|
|
|
</li></ul>
|
|
|
|
|
|
<a name="See-Also"></a>
|
|
<h1 class="chapter"><a href="ffmpeg.html#toc-See-Also">8. See Also</a></h1>
|
|
|
|
<p><a href="ffmpeg-all.html">ffmpeg-all</a>,
|
|
<a href="ffplay.html">ffplay</a>, <a href="ffprobe.html">ffprobe</a>, <a href="ffserver.html">ffserver</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>
|
|
<h1 class="chapter"><a href="ffmpeg.html#toc-Authors">9. Authors</a></h1>
|
|
|
|
<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
|
|
‘<tt>MAINTAINERS</tt>’ in the source code tree.
|
|
</p>
|
|
|
|
<footer class="footer pagination-right">
|
|
<span class="label label-info">This document was generated by <em>Kyle Schwarz</em> on <em>April 4, 2014</em> using <a href="http://www.nongnu.org/texi2html/"><em>texi2html 1.82</em></a>.</span></footer></div></div></body>
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