<p>FFmpeg is a powerful tool for manipulating audiovisual files. Unfortunately, it also has a steep learning curve, especially for users unfamiliar with a command line interface. This app helps users through the command generation process so that more people can reap the benefits of FFmpeg.</p>
<p>Each button displays helpful information about how to perform a wide variety of tasks using FFmpeg. To use this site, click on the task you would like to perform. A new window will open up with a sample command and a description of how that command works. You can copy this command and understand how the command works with a breakdown of each of the flags.</p>
<p>This page does not have search functionality, but you can open all recipes (second option in the sidebar) and use your browser's search tool (often ctrl+f or cmd+f) to perform a keyword search through all recipes.</p>
<spanclass="intro-lead">Tutorials</span>
<p>For FFmpeg basics, check out the program’s <ahref="https://ffmpeg.org/"target="_blank">official website</a>.</p>
<p>For instructions on how to install FFmpeg on Mac, Linux, and Windows, refer to Reto Kromer’s <ahref="https://avpres.net/FFmpeg/#ch1"target="_blank">installation instructions</a>.</p>
@@ -90,9 +93,9 @@
<h3>Streaming vs. Saving</h3>
<p>FFplay allows you to stream created video and FFmpeg allows you to save video.</p>
<p>The following command creates and saves a 10-second video of SMPTE bars:</p>
<p>The main difference is small but significant: the <code>-i</code> flag is required for FFmpeg but not required for FFplay. Additionally, the FFmpeg script needs to have <code>-t 5</code> and <code>output.mkv</code> added to specify the length of time to record and the place to save the video.</p>
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</div>
@@ -113,16 +116,17 @@
<p>It is also possible to apply multiple filters to an input, which are sequenced together in the filtergraph. A chained set of filters is called a filter chain, and a filtergraph may include multiple filter chains. Filters in a filterchain are separated from each other by commas (<code>,</code>), and filterchains are separated from each other by semicolons (<code>;</code>). For example, take the <ahref="#inverse-telecine">inverse telecine</a> command:</p>
<p>Here we have a filtergraph including one filter chain, which is made up of three video filters.</p>
<p>It is often prudent to enclose your filtergraph in quotation marks; this means that you can use spaces within the filtergraph. Using the inverse telecine example again, the following filter commands are all valid and equivalent:
but <code>-vf fieldmatch, yadif, decimate</code> is not valid.</p>
<p>It is often prudent to enclose your filtergraph in quotation marks; this means that you can use spaces within the filtergraph. Using the inverse telecine example again, the following filter commands are all valid and equivalent:</p>
<p>but <code>-vf fieldmatch, yadif, decimate</code> is not valid.</p>
<p>The ordering of the filters is significant. Video filters are applied in the order given, with the output of one filter being passed along as the input to the next filter in the chain. In the example above, <code>fieldmatch</code> reconstructs the original frames from the inverse telecined video, <code>yadif</code> deinterlaces (this is a failsafe in case any combed frames remain, for example if the source mixes telecined and real interlaced content), and <code>decimate</code> deletes duplicated frames. Clearly, it is not possible to delete duplicated frames before those frames are reconstructed.</p>
<h4>Notes</h4>
<ul>
<li><code>-vf</code> is an alias for <code>-filter:v</code></li>
<li>If the command involves more than one input or output, you must use the flag <code>-filter_complex</code> instead of <code>-vf</code>.</li>
<li>Straight quotation marks ("like this") rather than curved quotation marks (“like this”) should be used.</li>
</ul>
@@ -209,6 +213,24 @@
</div>
<!-- ends MKV to MP4 -->
<!-- Rewrap DV -->
<labelclass="recipe"for="rewrap-dv">Rewrap DV video to .dv file</label>
<p>This script will take a video that is encoded in the <ahref="https://en.wikipedia.org/wiki/DV"target="_blank">DV Codec</a> but wrapped in a different container (such as MOV) and rewrap it into a raw DV file (with the .dv extension). Since DV files potentially contain a great deal of provenance metadata within the DV stream, it is necessary to rewrap files in this method to avoid unintentional stripping of this metadata.</p>
<dl>
<dt>ffmpeg</dt><dd>starts the command</dd>
<dt>-i <i>input_file</i></dt><dd>path and name of the input file</dd>
<dt>-f rawvideo</dt><dd>this tells FFmpeg to pass the video stream as raw video data without remuxing. This step is what ensures the survival of embedded metadata versus a standard rewrap.</dd>
<dt>-c:v copy</dt><dd>copy the DV stream directly, without re-encoding.</dd>
<dt><i>output_file.dv</i></dt><dd>tells FFmpeg to use the DV wrapper for the output.</dd>
</dl>
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</div>
<!-- Rewrap DV -->
</div>
<divclass="well">
<h2id="transcode">Change codec (transcode)</h2>
@@ -239,7 +261,7 @@
<p>FFmpeg comes with more than one ProRes encoder:</p>
<ul>
<li><code>prores</code> is much faster, can be used for progressive video only, and seems to be better for video according to Rec. 601 (Recommendation ITU-R BT.601).</li>
<li><code>prores_ks</code> generates a better file, can also be used for interlaced video, allows also encoding of ProRes 4444 (<code>-c:v prores_ks -profile:v 4</code>), and seems to be better for video according to Rec. 709 (Recommendation ITU-R BT.709).</li>
<li><code>prores_ks</code> generates a better file, can also be used for interlaced video, allows also encoding of ProRes 4444 (<code>-c:v prores_ks -profile:v 4</code>) and ProRes 4444 XQ (<code>-c:v prores_ks -profile:v 5</code>), and seems to be better for video according to Rec. 709 (Recommendation ITU-R BT.709).</li>
</ul>
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</div>
@@ -424,7 +446,7 @@
<inputtype="checkbox"id="append_mp3">
<divclass="hiding">
<h3>Generate two access MP3s from input. One with appended audio (such as a copyright notice) and one unmodified.</h3>
<p>This script allows you to generate two derivative audio files from a master while appending audio from a separate file (for example a copyright or institutional notice) to one of them.</p>
<p>This command takes two or more files of the different file types and joins them together to make a single file.</p>
<p>The input files may differ in many respects - container, codec, chroma subsampling scheme, framerate, etc. However, the above command only works properly if the files to be combined have the same dimensions (e.g., 720x576). Also note that if the input files have different framerates, then the output file will be of variable framerate.</p>
<p>Some aspects of the input files will be normalised: for example, if an input file contains a video track and an audio track that do not have exactly the same duration, the shorter one will be padded. In the case of a shorter video track, the last frame will be repeated in order to cover the missing video; in the case of a shorter audio track, the audio stream will be padded with silence.</p>
<dl>
<dt>ffmpeg</dt><dd>starts the command</dd>
<dt>-i <i>input1.ext</i></dt><dd>path, name and extension of the first input file</dd>
<dt>-i <i>input2.ext</i></dt><dd>path, name and extension of the second input file</dd>
<dt>-i <i>input_1.ext</i></dt><dd>path, name and extension of the first input file</dd>
<dt>-i <i>input_2.ext</i></dt><dd>path, name and extension of the second input file</dd>
<dt>-filter_complex</dt><dd>states that a complex filtergraph will be used</dd>
<dt>"</dt><dd>quotation mark to start filtergraph</dd>
<dt>[0:v:0][0:a:0]</dt><dd>selects the first video stream and first audio stream from the first input.<br>
<h4>Variation: concatenating files of different resolutions</h4>
<p>To concatenate files of different resolutions, you need to resize the videos to have matching resolutions prior to concatenation. The most basic way to do this is by using a scale filter and giving the dimensions of the file you wish to match:</p>
<p>(The Lanczos scaling algorithm is recommended, as it is slower but better than the default bilinear algorithm).</p>
<p>The rescaling should be applied just before the point where the streams to be used in the output file are listed. Select the stream you want to rescale, apply the filter, and assign that to a variable name (<code>rescaled_video</code> in the below example). Then you use this variable name in the list of streams to be concatenated.</p>
<p>However, this will only have the desired visual output if the inputs have the same aspect ratio. If you wish to concatenate an SD and an HD file, you will also wish to pillarbox the SD file while upscaling. (See the <ahref="https://amiaopensource.github.io/ffmprovisr/#SD_HD_2">Convert 4:3 to pillarboxed HD</a> command). The full command would look like this:</p>
<p>Here, the first input is an SD file which needs to be upscaled to match the second input, which is 1920x1080. The scale filter enlarges the SD input to the height of the HD frame, keeping the 4:3 aspect ratio; then, the video is pillarboxed within a 1920x1080 frame.</p>
<h4>Variation: concatenating files of different framerates</h4>
<p>If the input files have different framerates, then the output file may be of variable framerate. To explicitly obtain an output file of constant framerate, you may wish convert an input (or multiple inputs) to a different framerate prior to concatenation.</p>
<p>You can speed up or slow down a file using the <code>fps</code> and <code>atempo</code> filters (see also the <ahref="https://amiaopensource.github.io/ffmprovisr/#modify_speed">Modify speed</a> command).</p>
<p>Here's an example of the full command, in which input_1 is 30fps, input_2 is 25fps, and 25fps is the desired output speed.</p>
<p>Note that the <code>fps</code> filter will drop or repeat frames as necessary in order to achieve the desired frame rate - see the FFmpeg <ahref="https://ffmpeg.org/ffmpeg-filters.html#fps-1"target="_blank">fps docs</a> for more details.</p>
<p>For more information, see the <ahref="https://trac.ffmpeg.org/wiki/Concatenate#differentcodec"target="_blank">FFmpeg wiki page on concatenating files of different types</a>.</p>
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</div>
@@ -997,7 +1034,7 @@
<dt>-ss 00:02:00</dt><dd>sets in point at 00:02:00</dd>
<dt>-to 00:55:00</dt><dd>sets out point at 00:55:00</dd>
<dt>-c copy</dt><dd>use stream copy mode (no re-encoding)<br>
<dt>-map 0</dt><dd>tells FFmpeg to map all streams of the input to the output.</dd>
<dt>-map 0</dt><dd>tells FFmpeg to map all streams of the input to the output.<br>
<b>Note:</b> watch out when using <code>-ss</code> with <code>-c copy</code> if the source is encoded with an interframe codec (e.g., H.264). Since FFmpeg must split on i-frames, it will seek to the nearest i-frame to begin the stream copy.</dd>
<dt><i>output_file</i></dt><dd>path, name and extension of the output file</dd>
</dl>
@@ -1118,7 +1155,7 @@
<dt>"</dt><dd>end of filtergraph</dd>
<dt><i>output file</i></dt><dd>path, name and extension of the output file</dd>
</dl>
<p><code>"yadif,format=yuv420p"</code> is an FFmpeg <ahref="https://trac.ffmpeg.org/wiki/FilteringGuide#FiltergraphChainFilterrelationship"target="_blank">filtergraph</a>. Here the filtergraph is made up of one filter chain, which is itself made up of the two filters (separated by the comma).<br>
<p><code>"yadif,format=yuv420p"</code> is an FFmpeg <ahref="https://trac.ffmpeg.org/wiki/FilteringGuide#FiltergraphChainFilterrelationship"target="_blank">filtergraph</a>. Here the filtergraph is made up of one filter chain, which is itself made up of the two filters (separated by the comma).<br>
The enclosing quote marks are necessary when you use spaces within the filtergraph, e.g. <code>-vf "yadif, format=yuv420p"</code>, and are included above as an example of good practice.</p>
<p><b>Note:</b> FFmpeg includes several deinterlacers apart from <ahref="https://ffmpeg.org/ffmpeg-filters.html#yadif-1"target="_blank">yadif</a>: <ahref="https://ffmpeg.org/ffmpeg-filters.html#bwdif"target="_blank">bwdif</a>, <ahref="https://ffmpeg.org/ffmpeg-filters.html#w3fdif"target="_blank">w3fdif</a>, <ahref="https://ffmpeg.org/ffmpeg-filters.html#kerndeint"target="_blank">kerndeint</a>, and <ahref="https://ffmpeg.org/ffmpeg-filters.html#nnedi"target="_blank">nnedi</a>.</p>
<p>For more H.264 encoding options, see the latter section of the <ahref="./index.html#transcode_h264">encode H.264 command</a>.</p>
<p>This decodes your video and displays any CRC checksum mismatches. These errors will display in your terminal like this: <code>[ffv1 @ 0x1b04660] CRC mismatch 350FBD8A!at 0.272000 seconds</code></p>
<p>Frame CRCs are enabled by default in FFV1 Version 3.</p>
<dl>
<dt>ffmpeg</dt><dd>starts the command</dd>
<dt>-report</dt><dd>Dump full command line and console output to a file named <i>ffmpeg-YYYYMMDD-HHMMSS.log</i> in the current directory. It also implies <code>-loglevel verbose</code>.</dd>
<dt>-i <i>input_file</i></dt><dd>path, name and extension of the input file</dd>
<dt>-f null</dt><dd>Video is decoded with the <code>null</code> muxer. This allows video decoding without creating an output file.</dd>
<dt>-</dt><dd>FFmpeg syntax requires a specified output, and <code>-</code> is just a place holder. No file is actually created.</dd>
<p>This decodes your video and displays any CRC checksum mismatches. These errors will display in your terminal like this: <code>[ffv1 @ 0x1b04660] CRC mismatch 350FBD8A!at 0.272000 seconds</code></p>
<p>Frame CRCs are enabled by default in FFV1 Version 3.</p>
<dl>
<dt>ffmpeg</dt><dd>starts the command</dd>
<dt>-report</dt><dd>Dump full command line and console output to a file named <i>ffmpeg-YYYYMMDD-HHMMSS.log</i> in the current directory. It also implies <code>-loglevel verbose</code>.</dd>
<dt>-i <i>input_file</i></dt><dd>path, name and extension of the input file</dd>
<dt>-f null</dt><dd>Video is decoded with the <code>null</code> muxer. This allows video decoding without creating an output file.</dd>
<dt>-</dt><dd>FFmpeg syntax requires a specified output, and <code>-</code> is just a place holder. No file is actually created. </dd>
<h2id="similar-tools">Similar tools: tips & tricks 🎩🐰</h2>
<divclass="well">
<p>This section introduces and explains the usage of some additional command line tools similar to FFmpeg for use in digital preservation workflows (and beyond!).</p>
<p>ImageMagick is a free and open-source software suite for displaying, converting, and editing raster image and vector image files.</p>
<p>It's official website can be found <ahref="https://www.imagemagick.org/script/index.php"target="_blank">here</a>.</p>
<p>Another great resource with lots of supplemental explanations of filters is available at <ahref="http://www.fmwconcepts.com/imagemagick/index.php"target="_blank">Fred's ImageMagick Scripts</a>.</p>
<p>Unlike many other command line tools, ImageMagick isn't summoned by calling its name. Rather, ImageMagick installs links to several more specific commands: <code>convert</code>, <code>montage</code>, and <code>mogrify</code>, to name a few.</p>
<pclass="link"></p>
</div>
<!-- End About ImageMagick -->
<!-- Compare two images -->
<labelclass="recipe"for="im_compare">Compare two images</label>
<dt>-metric ae</dt><dd>applies the absolute error count metric, returning the number of different pixels. <ahref="https://www.imagemagick.org/script/command-line-options.php#metric"target="_blank">Other parameters</a> are available for image comparison.</dd>
<dt><i>image1.ext image2.ext</i></dt><dd>takes two images as input</dd>
<dt>null:</dt><dd>throws away the comparison image that would be generated</dd>
</dl>
<pclass="link"></p>
</div>
<!-- ends Compare two images -->
<!-- Create thumbnails -->
<labelclass="recipe"for="im_thumbs">Create thumbnails of images</label>
<inputtype="checkbox"id="im_thumbs">
<divclass="hiding">
<h3>Create thumbnails</h3>
<p>Creates thumbnails for all files in a folder and saves them in that folder.</p>
<p>This script will also convert the file format, if the output has a different file extension than the input.</p>
<dl>
<dt>convert</dt><dd>starts the command</dd>
<dt>-i <i>input_file.ext</i></dt><dd>path and name of the input file</dd>
<dt>-resize 750</dt><dd>resizes the image to 750 pixels wide, retaining aspect ratio</dd>
<dt><i>output_file.ext</i></dt><dd>path and name of the output file</dd>
</dl>
<pclass="link"></p>
</div>
<!-- ends Resize to width -->
</div>
</div><!-- ends "content" -->
<!-- sample example -->
@@ -2313,7 +2499,7 @@ Change the above data-target field, the hover-over description, the button text,
<!-- ends sample example -->
<footerclass="footer">
<p>Made with ♥ at <ahref="https://wiki.curatecamp.org/index.php/Association_of_Moving_Image_Archivists_%26_Digital_Library_Federation_Hack_Day_2015"target="_blank">AMIA #AVhack15</a>! Contribute to the project via <ahref="https://github.com/amiaopensource/ffmprovisr">our GitHub page</a>!</p>
<p>Made with ♥ at <ahref="https://wiki.curatecamp.org/index.php/Association_of_Moving_Image_Archivists_%26_Digital_Library_Federation_Hack_Day_2015"target="_blank">AMIA #AVhack15</a>! Contribute to the project via <ahref="https://github.com/amiaopensource/ffmprovisr"target="_blank">our GitHub page</a>!</p>
$('#'+id).closest('div').find('.link').append("<small>Link to this command: <a href='https://amiaopensource.github.io/ffmprovisr/index.html"+window.location.hash+"'>https://amiaopensource.github.io/ffmprovisr/index.html"+window.location.hash+"</a></small>");
@@ -49,10 +49,13 @@ You can read our contributor code of conduct [here](https://github.com/amiaopens
## Contributors
* Gathered using [octohatrack](https://github.com/LABHR/octohatrack)
*GitHub Contributors*:
*Code Contributors*:
ablwr (Ashley)
bastibeckr (Basti Becker)
bturkus
dericed (Dave Rice)
edsu (Ed Summers)
jamessam (Jim Sam)
jfarbowitz (Jonathan Farbowitz)
kfrn (Katherine Frances Nagels)
kgrons (Kathryn Gronsbell)
@@ -62,17 +65,23 @@ pjotrek-b (Peter B.)
privatezero (Andrew Weaver)
retokromer (Reto Kromer)
rfraimow
*All Contributors*:
*All Contributors*:
ablwr (Ashley)
audiovisualopen
bastibeckr (Basti Becker)
brainwane (Sumana Harihareswara)
bturkus
dericed (Dave Rice)
drodz11 (Dave Rodriguez)
edsu (Ed Summers)
EG-tech (Ethan Gates)
federicomenaquintero (Federico Mena Quintero)
Fizz24
GregH18
jamessam (Jim Sam)
jfarbowitz (Jonathan Farbowitz)
JonnyTech
jronallo (Jason Ronallo)
kellyhaydon (metacynic)
kfrn (Katherine Frances Nagels)
@@ -80,16 +89,19 @@ kgrons (Kathryn Gronsbell)
kieranjol (Kieran O'Leary)
llogan (Lou)
mulvya
nkrabben (Nick Krabbenhoeft)
pjotrek-b (Peter B.)
privatezero (Andrew Weaver)
retokromer (Reto Kromer)
rfraimow
richardpl (Paul B Mahol)
ross-spencer (Ross Spencer)
todrobbins (Tod Robbins)
Repo: amiaopensource/ffmprovisr
GitHub Contributors: 12
All Contributors: 22
Code Contributors: 15
All Contributors: 30
Last updated: 2018-04-22 (4:2:2 Day)
## AVHack Team
@@ -99,6 +111,7 @@ All Contributors: 22
## Sister projects
[The Cable Bible](https://amiaopensource.github.io/cable-bible/): A Guide to Cables and Connectors Used for Audiovisual Tech
[Script Ahoy](http://dd388.github.io/crals/): Community Resource for Archivists and Librarians Scripting
[sourcecaster](https://datapraxis.github.io/sourcecaster/): helps you use the command line to work through common challenges that come up when working with digital primary sources.
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