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| author | Xavier Del Campo Romero <xavi.dcr@tutanota.com> | 2021-01-03 02:06:58 +0100 |
|---|---|---|
| committer | Xavier Del Campo Romero <xavi.dcr@tutanota.com> | 2021-01-03 02:52:19 +0100 |
| commit | 734eee1af2c21976e8f57c4ca498593a305fb22e (patch) | |
| tree | 8d5593567ce80c37820ea0c5ae76ff6bdb9e529c /Music/ffmpeg/doc/ffmpeg-utils.html | |
| parent | be200a681bed14801bb564c79f70e773e44e6c73 (diff) | |
| download | airport-734eee1af2c21976e8f57c4ca498593a305fb22e.tar.gz | |
Remove ffmpeg binary from project
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| -rw-r--r-- | Music/ffmpeg/doc/ffmpeg-utils.html | 1481 |
1 files changed, 0 insertions, 1481 deletions
diff --git a/Music/ffmpeg/doc/ffmpeg-utils.html b/Music/ffmpeg/doc/ffmpeg-utils.html deleted file mode 100644 index 53d54d5..0000000 --- a/Music/ffmpeg/doc/ffmpeg-utils.html +++ /dev/null @@ -1,1481 +0,0 @@ -<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> -<html> -<!-- Created by GNU Texinfo 5.2, http://www.gnu.org/software/texinfo/ --> - <head> - <meta charset="utf-8"> - <title> - FFmpeg Utilities Documentation - </title> - <meta name="viewport" content="width=device-width,initial-scale=1.0"> - <link rel="stylesheet" type="text/css" href="bootstrap.min.css"> - <link rel="stylesheet" type="text/css" href="style.min.css"> - </head> - <body> - <div class="container"> - <h1> - FFmpeg Utilities Documentation - </h1> -<div align="center"> -</div> - - -<a name="SEC_Top"></a> - -<a name="SEC_Contents"></a> -<h2 class="contents-heading">Table of Contents</h2> - -<div class="contents"> - -<ul class="no-bullet"> - <li><a name="toc-Description" href="#Description">1 Description</a></li> - <li><a name="toc-Syntax" href="#Syntax">2 Syntax</a> - <ul class="no-bullet"> - <li><a name="toc-Quoting-and-escaping" href="#Quoting-and-escaping">2.1 Quoting and escaping</a> - <ul class="no-bullet"> - <li><a name="toc-Examples" href="#Examples">2.1.1 Examples</a></li> - </ul></li> - <li><a name="toc-Date" href="#Date">2.2 Date</a></li> - <li><a name="toc-Time-duration" href="#Time-duration">2.3 Time duration</a> - <ul class="no-bullet"> - <li><a name="toc-Examples-1" href="#Examples-1">2.3.1 Examples</a></li> - </ul></li> - <li><a name="toc-Video-size" href="#Video-size">2.4 Video size</a></li> - <li><a name="toc-Video-rate" href="#Video-rate">2.5 Video rate</a></li> - <li><a name="toc-Ratio" href="#Ratio">2.6 Ratio</a></li> - <li><a name="toc-Color" href="#Color">2.7 Color</a></li> - <li><a name="toc-Channel-Layout" href="#Channel-Layout">2.8 Channel Layout</a></li> - </ul></li> - <li><a name="toc-Expression-Evaluation" href="#Expression-Evaluation">3 Expression Evaluation</a></li> - <li><a name="toc-OpenCL-Options" href="#OpenCL-Options">4 OpenCL Options</a></li> - <li><a name="toc-See-Also" href="#See-Also">5 See Also</a></li> - <li><a name="toc-Authors" href="#Authors">6 Authors</a></li> -</ul> -</div> - - -<a name="Description"></a> -<h2 class="chapter">1 Description<span class="pull-right"><a class="anchor hidden-xs" href="#Description" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Description" aria-hidden="true">TOC</a></span></h2> - -<p>This document describes some generic features and utilities provided -by the libavutil library. -</p> - -<a name="Syntax"></a> -<h2 class="chapter">2 Syntax<span class="pull-right"><a class="anchor hidden-xs" href="#Syntax" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Syntax" aria-hidden="true">TOC</a></span></h2> - -<p>This section documents the syntax and formats employed by the FFmpeg -libraries and tools. -</p> -<a name="quoting_005fand_005fescaping"></a><a name="Quoting-and-escaping"></a> -<h3 class="section">2.1 Quoting and escaping<span class="pull-right"><a class="anchor hidden-xs" href="#Quoting-and-escaping" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Quoting-and-escaping" aria-hidden="true">TOC</a></span></h3> - -<p>FFmpeg adopts the following quoting and escaping mechanism, unless -explicitly specified. The following rules are applied: -</p> -<ul> -<li> ‘<samp>'</samp>’ and ‘<samp>\</samp>’ are special characters (respectively used for -quoting and escaping). In addition to them, there might be other -special characters depending on the specific syntax where the escaping -and quoting are employed. - -</li><li> A special character is escaped by prefixing it with a ‘<samp>\</samp>’. - -</li><li> All characters enclosed between ‘<samp>''</samp>’ are included literally in the -parsed string. The quote character ‘<samp>'</samp>’ itself cannot be quoted, -so you may need to close the quote and escape it. - -</li><li> Leading and trailing whitespaces, unless escaped or quoted, are -removed from the parsed string. -</li></ul> - -<p>Note that you may need to add a second level of escaping when using -the command line or a script, which depends on the syntax of the -adopted shell language. -</p> -<p>The function <code>av_get_token</code> defined in -<samp>libavutil/avstring.h</samp> can be used to parse a token quoted or -escaped according to the rules defined above. -</p> -<p>The tool <samp>tools/ffescape</samp> in the FFmpeg source tree can be used -to automatically quote or escape a string in a script. -</p> -<a name="Examples"></a> -<h4 class="subsection">2.1.1 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples" aria-hidden="true">TOC</a></span></h4> - -<ul> -<li> Escape the string <code>Crime d'Amour</code> containing the <code>'</code> special -character: -<div class="example"> -<pre class="example">Crime d\'Amour -</pre></div> - -</li><li> The string above contains a quote, so the <code>'</code> needs to be escaped -when quoting it: -<div class="example"> -<pre class="example">'Crime d'\''Amour' -</pre></div> - -</li><li> Include leading or trailing whitespaces using quoting: -<div class="example"> -<pre class="example">' this string starts and ends with whitespaces ' -</pre></div> - -</li><li> Escaping and quoting can be mixed together: -<div class="example"> -<pre class="example">' The string '\'string\'' is a string ' -</pre></div> - -</li><li> To include a literal ‘<samp>\</samp>’ you can use either escaping or quoting: -<div class="example"> -<pre class="example">'c:\foo' can be written as c:\\foo -</pre></div> -</li></ul> - -<a name="date-syntax"></a><a name="Date"></a> -<h3 class="section">2.2 Date<span class="pull-right"><a class="anchor hidden-xs" href="#Date" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Date" aria-hidden="true">TOC</a></span></h3> - -<p>The accepted syntax is: -</p><div class="example"> -<pre class="example">[(YYYY-MM-DD|YYYYMMDD)[T|t| ]]((HH:MM:SS[.m...]]])|(HHMMSS[.m...]]]))[Z] -now -</pre></div> - -<p>If the value is "now" it takes the current time. -</p> -<p>Time is local time unless Z is appended, in which case it is -interpreted as UTC. -If the year-month-day part is not specified it takes the current -year-month-day. -</p> -<a name="time-duration-syntax"></a><a name="Time-duration"></a> -<h3 class="section">2.3 Time duration<span class="pull-right"><a class="anchor hidden-xs" href="#Time-duration" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Time-duration" aria-hidden="true">TOC</a></span></h3> - -<p>There are two accepted syntaxes for expressing time duration. -</p> -<div class="example"> -<pre class="example">[-][<var>HH</var>:]<var>MM</var>:<var>SS</var>[.<var>m</var>...] -</pre></div> - -<p><var>HH</var> expresses the number of hours, <var>MM</var> the number of minutes -for a maximum of 2 digits, and <var>SS</var> the number of seconds for a -maximum of 2 digits. The <var>m</var> at the end expresses decimal value for -<var>SS</var>. -</p> -<p><em>or</em> -</p> -<div class="example"> -<pre class="example">[-]<var>S</var>+[.<var>m</var>...] -</pre></div> - -<p><var>S</var> expresses the number of seconds, with the optional decimal part -<var>m</var>. -</p> -<p>In both expressions, the optional ‘<samp>-</samp>’ indicates negative duration. -</p> -<a name="Examples-1"></a> -<h4 class="subsection">2.3.1 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-1" aria-hidden="true">TOC</a></span></h4> - -<p>The following examples are all valid time duration: -</p> -<dl compact="compact"> -<dt>‘<samp>55</samp>’</dt> -<dd><p>55 seconds -</p> -</dd> -<dt>‘<samp>12:03:45</samp>’</dt> -<dd><p>12 hours, 03 minutes and 45 seconds -</p> -</dd> -<dt>‘<samp>23.189</samp>’</dt> -<dd><p>23.189 seconds -</p></dd> -</dl> - -<a name="video-size-syntax"></a><a name="Video-size"></a> -<h3 class="section">2.4 Video size<span class="pull-right"><a class="anchor hidden-xs" href="#Video-size" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Video-size" aria-hidden="true">TOC</a></span></h3> -<p>Specify the size of the sourced video, it may be a string of the form -<var>width</var>x<var>height</var>, or the name of a size abbreviation. -</p> -<p>The following abbreviations are recognized: -</p><dl compact="compact"> -<dt>‘<samp>ntsc</samp>’</dt> -<dd><p>720x480 -</p></dd> -<dt>‘<samp>pal</samp>’</dt> -<dd><p>720x576 -</p></dd> -<dt>‘<samp>qntsc</samp>’</dt> -<dd><p>352x240 -</p></dd> -<dt>‘<samp>qpal</samp>’</dt> -<dd><p>352x288 -</p></dd> -<dt>‘<samp>sntsc</samp>’</dt> -<dd><p>640x480 -</p></dd> -<dt>‘<samp>spal</samp>’</dt> -<dd><p>768x576 -</p></dd> -<dt>‘<samp>film</samp>’</dt> -<dd><p>352x240 -</p></dd> -<dt>‘<samp>ntsc-film</samp>’</dt> -<dd><p>352x240 -</p></dd> -<dt>‘<samp>sqcif</samp>’</dt> -<dd><p>128x96 -</p></dd> -<dt>‘<samp>qcif</samp>’</dt> -<dd><p>176x144 -</p></dd> -<dt>‘<samp>cif</samp>’</dt> -<dd><p>352x288 -</p></dd> -<dt>‘<samp>4cif</samp>’</dt> -<dd><p>704x576 -</p></dd> -<dt>‘<samp>16cif</samp>’</dt> -<dd><p>1408x1152 -</p></dd> -<dt>‘<samp>qqvga</samp>’</dt> -<dd><p>160x120 -</p></dd> -<dt>‘<samp>qvga</samp>’</dt> -<dd><p>320x240 -</p></dd> -<dt>‘<samp>vga</samp>’</dt> -<dd><p>640x480 -</p></dd> -<dt>‘<samp>svga</samp>’</dt> -<dd><p>800x600 -</p></dd> -<dt>‘<samp>xga</samp>’</dt> -<dd><p>1024x768 -</p></dd> -<dt>‘<samp>uxga</samp>’</dt> -<dd><p>1600x1200 -</p></dd> -<dt>‘<samp>qxga</samp>’</dt> -<dd><p>2048x1536 -</p></dd> -<dt>‘<samp>sxga</samp>’</dt> -<dd><p>1280x1024 -</p></dd> -<dt>‘<samp>qsxga</samp>’</dt> -<dd><p>2560x2048 -</p></dd> -<dt>‘<samp>hsxga</samp>’</dt> -<dd><p>5120x4096 -</p></dd> -<dt>‘<samp>wvga</samp>’</dt> -<dd><p>852x480 -</p></dd> -<dt>‘<samp>wxga</samp>’</dt> -<dd><p>1366x768 -</p></dd> -<dt>‘<samp>wsxga</samp>’</dt> -<dd><p>1600x1024 -</p></dd> -<dt>‘<samp>wuxga</samp>’</dt> -<dd><p>1920x1200 -</p></dd> -<dt>‘<samp>woxga</samp>’</dt> -<dd><p>2560x1600 -</p></dd> -<dt>‘<samp>wqsxga</samp>’</dt> -<dd><p>3200x2048 -</p></dd> -<dt>‘<samp>wquxga</samp>’</dt> -<dd><p>3840x2400 -</p></dd> -<dt>‘<samp>whsxga</samp>’</dt> -<dd><p>6400x4096 -</p></dd> -<dt>‘<samp>whuxga</samp>’</dt> -<dd><p>7680x4800 -</p></dd> -<dt>‘<samp>cga</samp>’</dt> -<dd><p>320x200 -</p></dd> -<dt>‘<samp>ega</samp>’</dt> -<dd><p>640x350 -</p></dd> -<dt>‘<samp>hd480</samp>’</dt> -<dd><p>852x480 -</p></dd> -<dt>‘<samp>hd720</samp>’</dt> -<dd><p>1280x720 -</p></dd> -<dt>‘<samp>hd1080</samp>’</dt> -<dd><p>1920x1080 -</p></dd> -<dt>‘<samp>2k</samp>’</dt> -<dd><p>2048x1080 -</p></dd> -<dt>‘<samp>2kflat</samp>’</dt> -<dd><p>1998x1080 -</p></dd> -<dt>‘<samp>2kscope</samp>’</dt> -<dd><p>2048x858 -</p></dd> -<dt>‘<samp>4k</samp>’</dt> -<dd><p>4096x2160 -</p></dd> -<dt>‘<samp>4kflat</samp>’</dt> -<dd><p>3996x2160 -</p></dd> -<dt>‘<samp>4kscope</samp>’</dt> -<dd><p>4096x1716 -</p></dd> -<dt>‘<samp>nhd</samp>’</dt> -<dd><p>640x360 -</p></dd> -<dt>‘<samp>hqvga</samp>’</dt> -<dd><p>240x160 -</p></dd> -<dt>‘<samp>wqvga</samp>’</dt> -<dd><p>400x240 -</p></dd> -<dt>‘<samp>fwqvga</samp>’</dt> -<dd><p>432x240 -</p></dd> -<dt>‘<samp>hvga</samp>’</dt> -<dd><p>480x320 -</p></dd> -<dt>‘<samp>qhd</samp>’</dt> -<dd><p>960x540 -</p></dd> -<dt>‘<samp>2kdci</samp>’</dt> -<dd><p>2048x1080 -</p></dd> -<dt>‘<samp>4kdci</samp>’</dt> -<dd><p>4096x2160 -</p></dd> -<dt>‘<samp>uhd2160</samp>’</dt> -<dd><p>3840x2160 -</p></dd> -<dt>‘<samp>uhd4320</samp>’</dt> -<dd><p>7680x4320 -</p></dd> -</dl> - -<a name="video-rate-syntax"></a><a name="Video-rate"></a> -<h3 class="section">2.5 Video rate<span class="pull-right"><a class="anchor hidden-xs" href="#Video-rate" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Video-rate" aria-hidden="true">TOC</a></span></h3> - -<p>Specify the frame rate of a video, expressed as the number of frames -generated per second. It has to be a string in the format -<var>frame_rate_num</var>/<var>frame_rate_den</var>, an integer number, a float -number or a valid video frame rate abbreviation. -</p> -<p>The following abbreviations are recognized: -</p><dl compact="compact"> -<dt>‘<samp>ntsc</samp>’</dt> -<dd><p>30000/1001 -</p></dd> -<dt>‘<samp>pal</samp>’</dt> -<dd><p>25/1 -</p></dd> -<dt>‘<samp>qntsc</samp>’</dt> -<dd><p>30000/1001 -</p></dd> -<dt>‘<samp>qpal</samp>’</dt> -<dd><p>25/1 -</p></dd> -<dt>‘<samp>sntsc</samp>’</dt> -<dd><p>30000/1001 -</p></dd> -<dt>‘<samp>spal</samp>’</dt> -<dd><p>25/1 -</p></dd> -<dt>‘<samp>film</samp>’</dt> -<dd><p>24/1 -</p></dd> -<dt>‘<samp>ntsc-film</samp>’</dt> -<dd><p>24000/1001 -</p></dd> -</dl> - -<a name="ratio-syntax"></a><a name="Ratio"></a> -<h3 class="section">2.6 Ratio<span class="pull-right"><a class="anchor hidden-xs" href="#Ratio" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Ratio" aria-hidden="true">TOC</a></span></h3> - -<p>A ratio can be expressed as an expression, or in the form -<var>numerator</var>:<var>denominator</var>. -</p> -<p>Note that a ratio with infinite (1/0) or negative value is -considered valid, so you should check on the returned value if you -want to exclude those values. -</p> -<p>The undefined value can be expressed using the "0:0" string. -</p> -<a name="color-syntax"></a><a name="Color"></a> -<h3 class="section">2.7 Color<span class="pull-right"><a class="anchor hidden-xs" href="#Color" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Color" aria-hidden="true">TOC</a></span></h3> - -<p>It can be the name of a color as defined below (case insensitive match) or a -<code>[0x|#]RRGGBB[AA]</code> sequence, possibly followed by @ and a string -representing the alpha component. -</p> -<p>The alpha component may be a string composed by "0x" followed by an -hexadecimal number or a decimal number between 0.0 and 1.0, which -represents the opacity value (‘<samp>0x00</samp>’ or ‘<samp>0.0</samp>’ means completely -transparent, ‘<samp>0xff</samp>’ or ‘<samp>1.0</samp>’ completely opaque). If the alpha -component is not specified then ‘<samp>0xff</samp>’ is assumed. -</p> -<p>The string ‘<samp>random</samp>’ will result in a random color. -</p> -<p>The following names of colors are recognized: -</p><dl compact="compact"> -<dt>‘<samp>AliceBlue</samp>’</dt> -<dd><p>0xF0F8FF -</p></dd> -<dt>‘<samp>AntiqueWhite</samp>’</dt> -<dd><p>0xFAEBD7 -</p></dd> -<dt>‘<samp>Aqua</samp>’</dt> -<dd><p>0x00FFFF -</p></dd> -<dt>‘<samp>Aquamarine</samp>’</dt> -<dd><p>0x7FFFD4 -</p></dd> -<dt>‘<samp>Azure</samp>’</dt> -<dd><p>0xF0FFFF -</p></dd> -<dt>‘<samp>Beige</samp>’</dt> -<dd><p>0xF5F5DC -</p></dd> -<dt>‘<samp>Bisque</samp>’</dt> -<dd><p>0xFFE4C4 -</p></dd> -<dt>‘<samp>Black</samp>’</dt> -<dd><p>0x000000 -</p></dd> -<dt>‘<samp>BlanchedAlmond</samp>’</dt> -<dd><p>0xFFEBCD -</p></dd> -<dt>‘<samp>Blue</samp>’</dt> -<dd><p>0x0000FF -</p></dd> -<dt>‘<samp>BlueViolet</samp>’</dt> -<dd><p>0x8A2BE2 -</p></dd> -<dt>‘<samp>Brown</samp>’</dt> -<dd><p>0xA52A2A -</p></dd> -<dt>‘<samp>BurlyWood</samp>’</dt> -<dd><p>0xDEB887 -</p></dd> -<dt>‘<samp>CadetBlue</samp>’</dt> -<dd><p>0x5F9EA0 -</p></dd> -<dt>‘<samp>Chartreuse</samp>’</dt> -<dd><p>0x7FFF00 -</p></dd> -<dt>‘<samp>Chocolate</samp>’</dt> -<dd><p>0xD2691E -</p></dd> -<dt>‘<samp>Coral</samp>’</dt> -<dd><p>0xFF7F50 -</p></dd> -<dt>‘<samp>CornflowerBlue</samp>’</dt> -<dd><p>0x6495ED -</p></dd> -<dt>‘<samp>Cornsilk</samp>’</dt> -<dd><p>0xFFF8DC -</p></dd> -<dt>‘<samp>Crimson</samp>’</dt> -<dd><p>0xDC143C -</p></dd> -<dt>‘<samp>Cyan</samp>’</dt> -<dd><p>0x00FFFF -</p></dd> -<dt>‘<samp>DarkBlue</samp>’</dt> -<dd><p>0x00008B -</p></dd> -<dt>‘<samp>DarkCyan</samp>’</dt> -<dd><p>0x008B8B -</p></dd> -<dt>‘<samp>DarkGoldenRod</samp>’</dt> -<dd><p>0xB8860B -</p></dd> -<dt>‘<samp>DarkGray</samp>’</dt> -<dd><p>0xA9A9A9 -</p></dd> -<dt>‘<samp>DarkGreen</samp>’</dt> -<dd><p>0x006400 -</p></dd> -<dt>‘<samp>DarkKhaki</samp>’</dt> -<dd><p>0xBDB76B -</p></dd> -<dt>‘<samp>DarkMagenta</samp>’</dt> -<dd><p>0x8B008B -</p></dd> -<dt>‘<samp>DarkOliveGreen</samp>’</dt> -<dd><p>0x556B2F -</p></dd> -<dt>‘<samp>Darkorange</samp>’</dt> -<dd><p>0xFF8C00 -</p></dd> -<dt>‘<samp>DarkOrchid</samp>’</dt> -<dd><p>0x9932CC -</p></dd> -<dt>‘<samp>DarkRed</samp>’</dt> -<dd><p>0x8B0000 -</p></dd> -<dt>‘<samp>DarkSalmon</samp>’</dt> -<dd><p>0xE9967A -</p></dd> -<dt>‘<samp>DarkSeaGreen</samp>’</dt> -<dd><p>0x8FBC8F -</p></dd> -<dt>‘<samp>DarkSlateBlue</samp>’</dt> -<dd><p>0x483D8B -</p></dd> -<dt>‘<samp>DarkSlateGray</samp>’</dt> -<dd><p>0x2F4F4F -</p></dd> -<dt>‘<samp>DarkTurquoise</samp>’</dt> -<dd><p>0x00CED1 -</p></dd> -<dt>‘<samp>DarkViolet</samp>’</dt> -<dd><p>0x9400D3 -</p></dd> -<dt>‘<samp>DeepPink</samp>’</dt> -<dd><p>0xFF1493 -</p></dd> -<dt>‘<samp>DeepSkyBlue</samp>’</dt> -<dd><p>0x00BFFF -</p></dd> -<dt>‘<samp>DimGray</samp>’</dt> -<dd><p>0x696969 -</p></dd> -<dt>‘<samp>DodgerBlue</samp>’</dt> -<dd><p>0x1E90FF -</p></dd> -<dt>‘<samp>FireBrick</samp>’</dt> -<dd><p>0xB22222 -</p></dd> -<dt>‘<samp>FloralWhite</samp>’</dt> -<dd><p>0xFFFAF0 -</p></dd> -<dt>‘<samp>ForestGreen</samp>’</dt> -<dd><p>0x228B22 -</p></dd> -<dt>‘<samp>Fuchsia</samp>’</dt> -<dd><p>0xFF00FF -</p></dd> -<dt>‘<samp>Gainsboro</samp>’</dt> -<dd><p>0xDCDCDC -</p></dd> -<dt>‘<samp>GhostWhite</samp>’</dt> -<dd><p>0xF8F8FF -</p></dd> -<dt>‘<samp>Gold</samp>’</dt> -<dd><p>0xFFD700 -</p></dd> -<dt>‘<samp>GoldenRod</samp>’</dt> -<dd><p>0xDAA520 -</p></dd> -<dt>‘<samp>Gray</samp>’</dt> -<dd><p>0x808080 -</p></dd> -<dt>‘<samp>Green</samp>’</dt> -<dd><p>0x008000 -</p></dd> -<dt>‘<samp>GreenYellow</samp>’</dt> -<dd><p>0xADFF2F -</p></dd> -<dt>‘<samp>HoneyDew</samp>’</dt> -<dd><p>0xF0FFF0 -</p></dd> -<dt>‘<samp>HotPink</samp>’</dt> -<dd><p>0xFF69B4 -</p></dd> -<dt>‘<samp>IndianRed</samp>’</dt> -<dd><p>0xCD5C5C -</p></dd> -<dt>‘<samp>Indigo</samp>’</dt> -<dd><p>0x4B0082 -</p></dd> -<dt>‘<samp>Ivory</samp>’</dt> -<dd><p>0xFFFFF0 -</p></dd> -<dt>‘<samp>Khaki</samp>’</dt> -<dd><p>0xF0E68C -</p></dd> -<dt>‘<samp>Lavender</samp>’</dt> -<dd><p>0xE6E6FA -</p></dd> -<dt>‘<samp>LavenderBlush</samp>’</dt> -<dd><p>0xFFF0F5 -</p></dd> -<dt>‘<samp>LawnGreen</samp>’</dt> -<dd><p>0x7CFC00 -</p></dd> -<dt>‘<samp>LemonChiffon</samp>’</dt> -<dd><p>0xFFFACD -</p></dd> -<dt>‘<samp>LightBlue</samp>’</dt> -<dd><p>0xADD8E6 -</p></dd> -<dt>‘<samp>LightCoral</samp>’</dt> -<dd><p>0xF08080 -</p></dd> -<dt>‘<samp>LightCyan</samp>’</dt> -<dd><p>0xE0FFFF -</p></dd> -<dt>‘<samp>LightGoldenRodYellow</samp>’</dt> -<dd><p>0xFAFAD2 -</p></dd> -<dt>‘<samp>LightGreen</samp>’</dt> -<dd><p>0x90EE90 -</p></dd> -<dt>‘<samp>LightGrey</samp>’</dt> -<dd><p>0xD3D3D3 -</p></dd> -<dt>‘<samp>LightPink</samp>’</dt> -<dd><p>0xFFB6C1 -</p></dd> -<dt>‘<samp>LightSalmon</samp>’</dt> -<dd><p>0xFFA07A -</p></dd> -<dt>‘<samp>LightSeaGreen</samp>’</dt> -<dd><p>0x20B2AA -</p></dd> -<dt>‘<samp>LightSkyBlue</samp>’</dt> -<dd><p>0x87CEFA -</p></dd> -<dt>‘<samp>LightSlateGray</samp>’</dt> -<dd><p>0x778899 -</p></dd> -<dt>‘<samp>LightSteelBlue</samp>’</dt> -<dd><p>0xB0C4DE -</p></dd> -<dt>‘<samp>LightYellow</samp>’</dt> -<dd><p>0xFFFFE0 -</p></dd> -<dt>‘<samp>Lime</samp>’</dt> -<dd><p>0x00FF00 -</p></dd> -<dt>‘<samp>LimeGreen</samp>’</dt> -<dd><p>0x32CD32 -</p></dd> -<dt>‘<samp>Linen</samp>’</dt> -<dd><p>0xFAF0E6 -</p></dd> -<dt>‘<samp>Magenta</samp>’</dt> -<dd><p>0xFF00FF -</p></dd> -<dt>‘<samp>Maroon</samp>’</dt> -<dd><p>0x800000 -</p></dd> -<dt>‘<samp>MediumAquaMarine</samp>’</dt> -<dd><p>0x66CDAA -</p></dd> -<dt>‘<samp>MediumBlue</samp>’</dt> -<dd><p>0x0000CD -</p></dd> -<dt>‘<samp>MediumOrchid</samp>’</dt> -<dd><p>0xBA55D3 -</p></dd> -<dt>‘<samp>MediumPurple</samp>’</dt> -<dd><p>0x9370D8 -</p></dd> -<dt>‘<samp>MediumSeaGreen</samp>’</dt> -<dd><p>0x3CB371 -</p></dd> -<dt>‘<samp>MediumSlateBlue</samp>’</dt> -<dd><p>0x7B68EE -</p></dd> -<dt>‘<samp>MediumSpringGreen</samp>’</dt> -<dd><p>0x00FA9A -</p></dd> -<dt>‘<samp>MediumTurquoise</samp>’</dt> -<dd><p>0x48D1CC -</p></dd> -<dt>‘<samp>MediumVioletRed</samp>’</dt> -<dd><p>0xC71585 -</p></dd> -<dt>‘<samp>MidnightBlue</samp>’</dt> -<dd><p>0x191970 -</p></dd> -<dt>‘<samp>MintCream</samp>’</dt> -<dd><p>0xF5FFFA -</p></dd> -<dt>‘<samp>MistyRose</samp>’</dt> -<dd><p>0xFFE4E1 -</p></dd> -<dt>‘<samp>Moccasin</samp>’</dt> -<dd><p>0xFFE4B5 -</p></dd> -<dt>‘<samp>NavajoWhite</samp>’</dt> -<dd><p>0xFFDEAD -</p></dd> -<dt>‘<samp>Navy</samp>’</dt> -<dd><p>0x000080 -</p></dd> -<dt>‘<samp>OldLace</samp>’</dt> -<dd><p>0xFDF5E6 -</p></dd> -<dt>‘<samp>Olive</samp>’</dt> -<dd><p>0x808000 -</p></dd> -<dt>‘<samp>OliveDrab</samp>’</dt> -<dd><p>0x6B8E23 -</p></dd> -<dt>‘<samp>Orange</samp>’</dt> -<dd><p>0xFFA500 -</p></dd> -<dt>‘<samp>OrangeRed</samp>’</dt> -<dd><p>0xFF4500 -</p></dd> -<dt>‘<samp>Orchid</samp>’</dt> -<dd><p>0xDA70D6 -</p></dd> -<dt>‘<samp>PaleGoldenRod</samp>’</dt> -<dd><p>0xEEE8AA -</p></dd> -<dt>‘<samp>PaleGreen</samp>’</dt> -<dd><p>0x98FB98 -</p></dd> -<dt>‘<samp>PaleTurquoise</samp>’</dt> -<dd><p>0xAFEEEE -</p></dd> -<dt>‘<samp>PaleVioletRed</samp>’</dt> -<dd><p>0xD87093 -</p></dd> -<dt>‘<samp>PapayaWhip</samp>’</dt> -<dd><p>0xFFEFD5 -</p></dd> -<dt>‘<samp>PeachPuff</samp>’</dt> -<dd><p>0xFFDAB9 -</p></dd> -<dt>‘<samp>Peru</samp>’</dt> -<dd><p>0xCD853F -</p></dd> -<dt>‘<samp>Pink</samp>’</dt> -<dd><p>0xFFC0CB -</p></dd> -<dt>‘<samp>Plum</samp>’</dt> -<dd><p>0xDDA0DD -</p></dd> -<dt>‘<samp>PowderBlue</samp>’</dt> -<dd><p>0xB0E0E6 -</p></dd> -<dt>‘<samp>Purple</samp>’</dt> -<dd><p>0x800080 -</p></dd> -<dt>‘<samp>Red</samp>’</dt> -<dd><p>0xFF0000 -</p></dd> -<dt>‘<samp>RosyBrown</samp>’</dt> -<dd><p>0xBC8F8F -</p></dd> -<dt>‘<samp>RoyalBlue</samp>’</dt> -<dd><p>0x4169E1 -</p></dd> -<dt>‘<samp>SaddleBrown</samp>’</dt> -<dd><p>0x8B4513 -</p></dd> -<dt>‘<samp>Salmon</samp>’</dt> -<dd><p>0xFA8072 -</p></dd> -<dt>‘<samp>SandyBrown</samp>’</dt> -<dd><p>0xF4A460 -</p></dd> -<dt>‘<samp>SeaGreen</samp>’</dt> -<dd><p>0x2E8B57 -</p></dd> -<dt>‘<samp>SeaShell</samp>’</dt> -<dd><p>0xFFF5EE -</p></dd> -<dt>‘<samp>Sienna</samp>’</dt> -<dd><p>0xA0522D -</p></dd> -<dt>‘<samp>Silver</samp>’</dt> -<dd><p>0xC0C0C0 -</p></dd> -<dt>‘<samp>SkyBlue</samp>’</dt> -<dd><p>0x87CEEB -</p></dd> -<dt>‘<samp>SlateBlue</samp>’</dt> -<dd><p>0x6A5ACD -</p></dd> -<dt>‘<samp>SlateGray</samp>’</dt> -<dd><p>0x708090 -</p></dd> -<dt>‘<samp>Snow</samp>’</dt> -<dd><p>0xFFFAFA -</p></dd> -<dt>‘<samp>SpringGreen</samp>’</dt> -<dd><p>0x00FF7F -</p></dd> -<dt>‘<samp>SteelBlue</samp>’</dt> -<dd><p>0x4682B4 -</p></dd> -<dt>‘<samp>Tan</samp>’</dt> -<dd><p>0xD2B48C -</p></dd> -<dt>‘<samp>Teal</samp>’</dt> -<dd><p>0x008080 -</p></dd> -<dt>‘<samp>Thistle</samp>’</dt> -<dd><p>0xD8BFD8 -</p></dd> -<dt>‘<samp>Tomato</samp>’</dt> -<dd><p>0xFF6347 -</p></dd> -<dt>‘<samp>Turquoise</samp>’</dt> -<dd><p>0x40E0D0 -</p></dd> -<dt>‘<samp>Violet</samp>’</dt> -<dd><p>0xEE82EE -</p></dd> -<dt>‘<samp>Wheat</samp>’</dt> -<dd><p>0xF5DEB3 -</p></dd> -<dt>‘<samp>White</samp>’</dt> -<dd><p>0xFFFFFF -</p></dd> -<dt>‘<samp>WhiteSmoke</samp>’</dt> -<dd><p>0xF5F5F5 -</p></dd> -<dt>‘<samp>Yellow</samp>’</dt> -<dd><p>0xFFFF00 -</p></dd> -<dt>‘<samp>YellowGreen</samp>’</dt> -<dd><p>0x9ACD32 -</p></dd> -</dl> - -<a name="channel-layout-syntax"></a><a name="Channel-Layout"></a> -<h3 class="section">2.8 Channel Layout<span class="pull-right"><a class="anchor hidden-xs" href="#Channel-Layout" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Channel-Layout" aria-hidden="true">TOC</a></span></h3> - -<p>A channel layout specifies the spatial disposition of the channels in -a multi-channel audio stream. To specify a channel layout, FFmpeg -makes use of a special syntax. -</p> -<p>Individual channels are identified by an id, as given by the table -below: -</p><dl compact="compact"> -<dt>‘<samp>FL</samp>’</dt> -<dd><p>front left -</p></dd> -<dt>‘<samp>FR</samp>’</dt> -<dd><p>front right -</p></dd> -<dt>‘<samp>FC</samp>’</dt> -<dd><p>front center -</p></dd> -<dt>‘<samp>LFE</samp>’</dt> -<dd><p>low frequency -</p></dd> -<dt>‘<samp>BL</samp>’</dt> -<dd><p>back left -</p></dd> -<dt>‘<samp>BR</samp>’</dt> -<dd><p>back right -</p></dd> -<dt>‘<samp>FLC</samp>’</dt> -<dd><p>front left-of-center -</p></dd> -<dt>‘<samp>FRC</samp>’</dt> -<dd><p>front right-of-center -</p></dd> -<dt>‘<samp>BC</samp>’</dt> -<dd><p>back center -</p></dd> -<dt>‘<samp>SL</samp>’</dt> -<dd><p>side left -</p></dd> -<dt>‘<samp>SR</samp>’</dt> -<dd><p>side right -</p></dd> -<dt>‘<samp>TC</samp>’</dt> -<dd><p>top center -</p></dd> -<dt>‘<samp>TFL</samp>’</dt> -<dd><p>top front left -</p></dd> -<dt>‘<samp>TFC</samp>’</dt> -<dd><p>top front center -</p></dd> -<dt>‘<samp>TFR</samp>’</dt> -<dd><p>top front right -</p></dd> -<dt>‘<samp>TBL</samp>’</dt> -<dd><p>top back left -</p></dd> -<dt>‘<samp>TBC</samp>’</dt> -<dd><p>top back center -</p></dd> -<dt>‘<samp>TBR</samp>’</dt> -<dd><p>top back right -</p></dd> -<dt>‘<samp>DL</samp>’</dt> -<dd><p>downmix left -</p></dd> -<dt>‘<samp>DR</samp>’</dt> -<dd><p>downmix right -</p></dd> -<dt>‘<samp>WL</samp>’</dt> -<dd><p>wide left -</p></dd> -<dt>‘<samp>WR</samp>’</dt> -<dd><p>wide right -</p></dd> -<dt>‘<samp>SDL</samp>’</dt> -<dd><p>surround direct left -</p></dd> -<dt>‘<samp>SDR</samp>’</dt> -<dd><p>surround direct right -</p></dd> -<dt>‘<samp>LFE2</samp>’</dt> -<dd><p>low frequency 2 -</p></dd> -</dl> - -<p>Standard channel layout compositions can be specified by using the -following identifiers: -</p><dl compact="compact"> -<dt>‘<samp>mono</samp>’</dt> -<dd><p>FC -</p></dd> -<dt>‘<samp>stereo</samp>’</dt> -<dd><p>FL+FR -</p></dd> -<dt>‘<samp>2.1</samp>’</dt> -<dd><p>FL+FR+LFE -</p></dd> -<dt>‘<samp>3.0</samp>’</dt> -<dd><p>FL+FR+FC -</p></dd> -<dt>‘<samp>3.0(back)</samp>’</dt> -<dd><p>FL+FR+BC -</p></dd> -<dt>‘<samp>4.0</samp>’</dt> -<dd><p>FL+FR+FC+BC -</p></dd> -<dt>‘<samp>quad</samp>’</dt> -<dd><p>FL+FR+BL+BR -</p></dd> -<dt>‘<samp>quad(side)</samp>’</dt> -<dd><p>FL+FR+SL+SR -</p></dd> -<dt>‘<samp>3.1</samp>’</dt> -<dd><p>FL+FR+FC+LFE -</p></dd> -<dt>‘<samp>5.0</samp>’</dt> -<dd><p>FL+FR+FC+BL+BR -</p></dd> -<dt>‘<samp>5.0(side)</samp>’</dt> -<dd><p>FL+FR+FC+SL+SR -</p></dd> -<dt>‘<samp>4.1</samp>’</dt> -<dd><p>FL+FR+FC+LFE+BC -</p></dd> -<dt>‘<samp>5.1</samp>’</dt> -<dd><p>FL+FR+FC+LFE+BL+BR -</p></dd> -<dt>‘<samp>5.1(side)</samp>’</dt> -<dd><p>FL+FR+FC+LFE+SL+SR -</p></dd> -<dt>‘<samp>6.0</samp>’</dt> -<dd><p>FL+FR+FC+BC+SL+SR -</p></dd> -<dt>‘<samp>6.0(front)</samp>’</dt> -<dd><p>FL+FR+FLC+FRC+SL+SR -</p></dd> -<dt>‘<samp>hexagonal</samp>’</dt> -<dd><p>FL+FR+FC+BL+BR+BC -</p></dd> -<dt>‘<samp>6.1</samp>’</dt> -<dd><p>FL+FR+FC+LFE+BC+SL+SR -</p></dd> -<dt>‘<samp>6.1</samp>’</dt> -<dd><p>FL+FR+FC+LFE+BL+BR+BC -</p></dd> -<dt>‘<samp>6.1(front)</samp>’</dt> -<dd><p>FL+FR+LFE+FLC+FRC+SL+SR -</p></dd> -<dt>‘<samp>7.0</samp>’</dt> -<dd><p>FL+FR+FC+BL+BR+SL+SR -</p></dd> -<dt>‘<samp>7.0(front)</samp>’</dt> -<dd><p>FL+FR+FC+FLC+FRC+SL+SR -</p></dd> -<dt>‘<samp>7.1</samp>’</dt> -<dd><p>FL+FR+FC+LFE+BL+BR+SL+SR -</p></dd> -<dt>‘<samp>7.1(wide)</samp>’</dt> -<dd><p>FL+FR+FC+LFE+BL+BR+FLC+FRC -</p></dd> -<dt>‘<samp>7.1(wide-side)</samp>’</dt> -<dd><p>FL+FR+FC+LFE+FLC+FRC+SL+SR -</p></dd> -<dt>‘<samp>octagonal</samp>’</dt> -<dd><p>FL+FR+FC+BL+BR+BC+SL+SR -</p></dd> -<dt>‘<samp>downmix</samp>’</dt> -<dd><p>DL+DR -</p></dd> -</dl> - -<p>A custom channel layout can be specified as a sequence of terms, separated by -’+’ or ’|’. Each term can be: -</p><ul> -<li> the name of a standard channel layout (e.g. ‘<samp>mono</samp>’, -‘<samp>stereo</samp>’, ‘<samp>4.0</samp>’, ‘<samp>quad</samp>’, ‘<samp>5.0</samp>’, etc.) - -</li><li> the name of a single channel (e.g. ‘<samp>FL</samp>’, ‘<samp>FR</samp>’, ‘<samp>FC</samp>’, ‘<samp>LFE</samp>’, etc.) - -</li><li> a number of channels, in decimal, optionally followed by ’c’, yielding -the default channel layout for that number of channels (see the -function <code>av_get_default_channel_layout</code>) - -</li><li> a channel layout mask, in hexadecimal starting with "0x" (see the -<code>AV_CH_*</code> macros in <samp>libavutil/channel_layout.h</samp>. -</li></ul> - -<p>Starting from libavutil version 53 the trailing character "c" to -specify a number of channels will be required, while a channel layout -mask could also be specified as a decimal number (if and only if not -followed by "c"). -</p> -<p>See also the function <code>av_get_channel_layout</code> defined in -<samp>libavutil/channel_layout.h</samp>. -</p> -<a name="Expression-Evaluation"></a> -<h2 class="chapter">3 Expression Evaluation<span class="pull-right"><a class="anchor hidden-xs" href="#Expression-Evaluation" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Expression-Evaluation" aria-hidden="true">TOC</a></span></h2> - -<p>When evaluating an arithmetic expression, FFmpeg uses an internal -formula evaluator, implemented through the <samp>libavutil/eval.h</samp> -interface. -</p> -<p>An expression may contain unary, binary operators, constants, and -functions. -</p> -<p>Two expressions <var>expr1</var> and <var>expr2</var> can be combined to form -another expression "<var>expr1</var>;<var>expr2</var>". -<var>expr1</var> and <var>expr2</var> are evaluated in turn, and the new -expression evaluates to the value of <var>expr2</var>. -</p> -<p>The following binary operators are available: <code>+</code>, <code>-</code>, -<code>*</code>, <code>/</code>, <code>^</code>. -</p> -<p>The following unary operators are available: <code>+</code>, <code>-</code>. -</p> -<p>The following functions are available: -</p><dl compact="compact"> -<dt><samp>abs(x)</samp></dt> -<dd><p>Compute absolute value of <var>x</var>. -</p> -</dd> -<dt><samp>acos(x)</samp></dt> -<dd><p>Compute arccosine of <var>x</var>. -</p> -</dd> -<dt><samp>asin(x)</samp></dt> -<dd><p>Compute arcsine of <var>x</var>. -</p> -</dd> -<dt><samp>atan(x)</samp></dt> -<dd><p>Compute arctangent of <var>x</var>. -</p> -</dd> -<dt><samp>between(x, min, max)</samp></dt> -<dd><p>Return 1 if <var>x</var> is greater than or equal to <var>min</var> and lesser than or -equal to <var>max</var>, 0 otherwise. -</p> -</dd> -<dt><samp>bitand(x, y)</samp></dt> -<dt><samp>bitor(x, y)</samp></dt> -<dd><p>Compute bitwise and/or operation on <var>x</var> and <var>y</var>. -</p> -<p>The results of the evaluation of <var>x</var> and <var>y</var> are converted to -integers before executing the bitwise operation. -</p> -<p>Note that both the conversion to integer and the conversion back to -floating point can lose precision. Beware of unexpected results for -large numbers (usually 2^53 and larger). -</p> -</dd> -<dt><samp>ceil(expr)</samp></dt> -<dd><p>Round the value of expression <var>expr</var> upwards to the nearest -integer. For example, "ceil(1.5)" is "2.0". -</p> -</dd> -<dt><samp>clip(x, min, max)</samp></dt> -<dd><p>Return the value of <var>x</var> clipped between <var>min</var> and <var>max</var>. -</p> -</dd> -<dt><samp>cos(x)</samp></dt> -<dd><p>Compute cosine of <var>x</var>. -</p> -</dd> -<dt><samp>cosh(x)</samp></dt> -<dd><p>Compute hyperbolic cosine of <var>x</var>. -</p> -</dd> -<dt><samp>eq(x, y)</samp></dt> -<dd><p>Return 1 if <var>x</var> and <var>y</var> are equivalent, 0 otherwise. -</p> -</dd> -<dt><samp>exp(x)</samp></dt> -<dd><p>Compute exponential of <var>x</var> (with base <code>e</code>, the Euler’s number). -</p> -</dd> -<dt><samp>floor(expr)</samp></dt> -<dd><p>Round the value of expression <var>expr</var> downwards to the nearest -integer. For example, "floor(-1.5)" is "-2.0". -</p> -</dd> -<dt><samp>gauss(x)</samp></dt> -<dd><p>Compute Gauss function of <var>x</var>, corresponding to -<code>exp(-x*x/2) / sqrt(2*PI)</code>. -</p> -</dd> -<dt><samp>gcd(x, y)</samp></dt> -<dd><p>Return the greatest common divisor of <var>x</var> and <var>y</var>. If both <var>x</var> and -<var>y</var> are 0 or either or both are less than zero then behavior is undefined. -</p> -</dd> -<dt><samp>gt(x, y)</samp></dt> -<dd><p>Return 1 if <var>x</var> is greater than <var>y</var>, 0 otherwise. -</p> -</dd> -<dt><samp>gte(x, y)</samp></dt> -<dd><p>Return 1 if <var>x</var> is greater than or equal to <var>y</var>, 0 otherwise. -</p> -</dd> -<dt><samp>hypot(x, y)</samp></dt> -<dd><p>This function is similar to the C function with the same name; it returns -"sqrt(<var>x</var>*<var>x</var> + <var>y</var>*<var>y</var>)", the length of the hypotenuse of a -right triangle with sides of length <var>x</var> and <var>y</var>, or the distance of the -point (<var>x</var>, <var>y</var>) from the origin. -</p> -</dd> -<dt><samp>if(x, y)</samp></dt> -<dd><p>Evaluate <var>x</var>, and if the result is non-zero return the result of -the evaluation of <var>y</var>, return 0 otherwise. -</p> -</dd> -<dt><samp>if(x, y, z)</samp></dt> -<dd><p>Evaluate <var>x</var>, and if the result is non-zero return the evaluation -result of <var>y</var>, otherwise the evaluation result of <var>z</var>. -</p> -</dd> -<dt><samp>ifnot(x, y)</samp></dt> -<dd><p>Evaluate <var>x</var>, and if the result is zero return the result of the -evaluation of <var>y</var>, return 0 otherwise. -</p> -</dd> -<dt><samp>ifnot(x, y, z)</samp></dt> -<dd><p>Evaluate <var>x</var>, and if the result is zero return the evaluation -result of <var>y</var>, otherwise the evaluation result of <var>z</var>. -</p> -</dd> -<dt><samp>isinf(x)</samp></dt> -<dd><p>Return 1.0 if <var>x</var> is +/-INFINITY, 0.0 otherwise. -</p> -</dd> -<dt><samp>isnan(x)</samp></dt> -<dd><p>Return 1.0 if <var>x</var> is NAN, 0.0 otherwise. -</p> -</dd> -<dt><samp>ld(var)</samp></dt> -<dd><p>Load the value of the internal variable with number -<var>var</var>, which was previously stored with st(<var>var</var>, <var>expr</var>). -The function returns the loaded value. -</p> -</dd> -<dt><samp>log(x)</samp></dt> -<dd><p>Compute natural logarithm of <var>x</var>. -</p> -</dd> -<dt><samp>lt(x, y)</samp></dt> -<dd><p>Return 1 if <var>x</var> is lesser than <var>y</var>, 0 otherwise. -</p> -</dd> -<dt><samp>lte(x, y)</samp></dt> -<dd><p>Return 1 if <var>x</var> is lesser than or equal to <var>y</var>, 0 otherwise. -</p> -</dd> -<dt><samp>max(x, y)</samp></dt> -<dd><p>Return the maximum between <var>x</var> and <var>y</var>. -</p> -</dd> -<dt><samp>min(x, y)</samp></dt> -<dd><p>Return the minimum between <var>x</var> and <var>y</var>. -</p> -</dd> -<dt><samp>mod(x, y)</samp></dt> -<dd><p>Compute the remainder of division of <var>x</var> by <var>y</var>. -</p> -</dd> -<dt><samp>not(expr)</samp></dt> -<dd><p>Return 1.0 if <var>expr</var> is zero, 0.0 otherwise. -</p> -</dd> -<dt><samp>pow(x, y)</samp></dt> -<dd><p>Compute the power of <var>x</var> elevated <var>y</var>, it is equivalent to -"(<var>x</var>)^(<var>y</var>)". -</p> -</dd> -<dt><samp>print(t)</samp></dt> -<dt><samp>print(t, l)</samp></dt> -<dd><p>Print the value of expression <var>t</var> with loglevel <var>l</var>. If -<var>l</var> is not specified then a default log level is used. -Returns the value of the expression printed. -</p> -<p>Prints t with loglevel l -</p> -</dd> -<dt><samp>random(x)</samp></dt> -<dd><p>Return a pseudo random value between 0.0 and 1.0. <var>x</var> is the index of the -internal variable which will be used to save the seed/state. -</p> -</dd> -<dt><samp>root(expr, max)</samp></dt> -<dd><p>Find an input value for which the function represented by <var>expr</var> -with argument <var>ld(0)</var> is 0 in the interval 0..<var>max</var>. -</p> -<p>The expression in <var>expr</var> must denote a continuous function or the -result is undefined. -</p> -<p><var>ld(0)</var> is used to represent the function input value, which means -that the given expression will be evaluated multiple times with -various input values that the expression can access through -<code>ld(0)</code>. When the expression evaluates to 0 then the -corresponding input value will be returned. -</p> -</dd> -<dt><samp>sin(x)</samp></dt> -<dd><p>Compute sine of <var>x</var>. -</p> -</dd> -<dt><samp>sinh(x)</samp></dt> -<dd><p>Compute hyperbolic sine of <var>x</var>. -</p> -</dd> -<dt><samp>sqrt(expr)</samp></dt> -<dd><p>Compute the square root of <var>expr</var>. This is equivalent to -"(<var>expr</var>)^.5". -</p> -</dd> -<dt><samp>squish(x)</samp></dt> -<dd><p>Compute expression <code>1/(1 + exp(4*x))</code>. -</p> -</dd> -<dt><samp>st(var, expr)</samp></dt> -<dd><p>Store the value of the expression <var>expr</var> in an internal -variable. <var>var</var> specifies the number of the variable where to -store the value, and it is a value ranging from 0 to 9. The function -returns the value stored in the internal variable. -Note, Variables are currently not shared between expressions. -</p> -</dd> -<dt><samp>tan(x)</samp></dt> -<dd><p>Compute tangent of <var>x</var>. -</p> -</dd> -<dt><samp>tanh(x)</samp></dt> -<dd><p>Compute hyperbolic tangent of <var>x</var>. -</p> -</dd> -<dt><samp>taylor(expr, x)</samp></dt> -<dt><samp>taylor(expr, x, id)</samp></dt> -<dd><p>Evaluate a Taylor series at <var>x</var>, given an expression representing -the <code>ld(id)</code>-th derivative of a function at 0. -</p> -<p>When the series does not converge the result is undefined. -</p> -<p><var>ld(id)</var> is used to represent the derivative order in <var>expr</var>, -which means that the given expression will be evaluated multiple times -with various input values that the expression can access through -<code>ld(id)</code>. If <var>id</var> is not specified then 0 is assumed. -</p> -<p>Note, when you have the derivatives at y instead of 0, -<code>taylor(expr, x-y)</code> can be used. -</p> -</dd> -<dt><samp>time(0)</samp></dt> -<dd><p>Return the current (wallclock) time in seconds. -</p> -</dd> -<dt><samp>trunc(expr)</samp></dt> -<dd><p>Round the value of expression <var>expr</var> towards zero to the nearest -integer. For example, "trunc(-1.5)" is "-1.0". -</p> -</dd> -<dt><samp>while(cond, expr)</samp></dt> -<dd><p>Evaluate expression <var>expr</var> while the expression <var>cond</var> is -non-zero, and returns the value of the last <var>expr</var> evaluation, or -NAN if <var>cond</var> was always false. -</p></dd> -</dl> - -<p>The following constants are available: -</p><dl compact="compact"> -<dt><samp>PI</samp></dt> -<dd><p>area of the unit disc, approximately 3.14 -</p></dd> -<dt><samp>E</samp></dt> -<dd><p>exp(1) (Euler’s number), approximately 2.718 -</p></dd> -<dt><samp>PHI</samp></dt> -<dd><p>golden ratio (1+sqrt(5))/2, approximately 1.618 -</p></dd> -</dl> - -<p>Assuming that an expression is considered "true" if it has a non-zero -value, note that: -</p> -<p><code>*</code> works like AND -</p> -<p><code>+</code> works like OR -</p> -<p>For example the construct: -</p><div class="example"> -<pre class="example">if (A AND B) then C -</pre></div> -<p>is equivalent to: -</p><div class="example"> -<pre class="example">if(A*B, C) -</pre></div> - -<p>In your C code, you can extend the list of unary and binary functions, -and define recognized constants, so that they are available for your -expressions. -</p> -<p>The evaluator also recognizes the International System unit prefixes. -If ’i’ is appended after the prefix, binary prefixes are used, which -are based on powers of 1024 instead of powers of 1000. -The ’B’ postfix multiplies the value by 8, and can be appended after a -unit prefix or used alone. This allows using for example ’KB’, ’MiB’, -’G’ and ’B’ as number postfix. -</p> -<p>The list of available International System prefixes follows, with -indication of the corresponding powers of 10 and of 2. -</p><dl compact="compact"> -<dt><samp>y</samp></dt> -<dd><p>10^-24 / 2^-80 -</p></dd> -<dt><samp>z</samp></dt> -<dd><p>10^-21 / 2^-70 -</p></dd> -<dt><samp>a</samp></dt> -<dd><p>10^-18 / 2^-60 -</p></dd> -<dt><samp>f</samp></dt> -<dd><p>10^-15 / 2^-50 -</p></dd> -<dt><samp>p</samp></dt> -<dd><p>10^-12 / 2^-40 -</p></dd> -<dt><samp>n</samp></dt> -<dd><p>10^-9 / 2^-30 -</p></dd> -<dt><samp>u</samp></dt> -<dd><p>10^-6 / 2^-20 -</p></dd> -<dt><samp>m</samp></dt> -<dd><p>10^-3 / 2^-10 -</p></dd> -<dt><samp>c</samp></dt> -<dd><p>10^-2 -</p></dd> -<dt><samp>d</samp></dt> -<dd><p>10^-1 -</p></dd> -<dt><samp>h</samp></dt> -<dd><p>10^2 -</p></dd> -<dt><samp>k</samp></dt> -<dd><p>10^3 / 2^10 -</p></dd> -<dt><samp>K</samp></dt> -<dd><p>10^3 / 2^10 -</p></dd> -<dt><samp>M</samp></dt> -<dd><p>10^6 / 2^20 -</p></dd> -<dt><samp>G</samp></dt> -<dd><p>10^9 / 2^30 -</p></dd> -<dt><samp>T</samp></dt> -<dd><p>10^12 / 2^40 -</p></dd> -<dt><samp>P</samp></dt> -<dd><p>10^15 / 2^40 -</p></dd> -<dt><samp>E</samp></dt> -<dd><p>10^18 / 2^50 -</p></dd> -<dt><samp>Z</samp></dt> -<dd><p>10^21 / 2^60 -</p></dd> -<dt><samp>Y</samp></dt> -<dd><p>10^24 / 2^70 -</p></dd> -</dl> - - -<a name="OpenCL-Options"></a> -<h2 class="chapter">4 OpenCL Options<span class="pull-right"><a class="anchor hidden-xs" href="#OpenCL-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-OpenCL-Options" aria-hidden="true">TOC</a></span></h2> - -<p>When FFmpeg is configured with <code>--enable-opencl</code>, it is possible -to set the options for the global OpenCL context. -</p> -<p>The list of supported options follows: -</p> -<dl compact="compact"> -<dt><samp>build_options</samp></dt> -<dd><p>Set build options used to compile the registered kernels. -</p> -<p>See reference "OpenCL Specification Version: 1.2 chapter 5.6.4". -</p> -</dd> -<dt><samp>platform_idx</samp></dt> -<dd><p>Select the index of the platform to run OpenCL code. -</p> -<p>The specified index must be one of the indexes in the device list -which can be obtained with <code>ffmpeg -opencl_bench</code> or <code>av_opencl_get_device_list()</code>. -</p> -</dd> -<dt><samp>device_idx</samp></dt> -<dd><p>Select the index of the device used to run OpenCL code. -</p> -<p>The specified index must be one of the indexes in the device list which -can be obtained with <code>ffmpeg -opencl_bench</code> or <code>av_opencl_get_device_list()</code>. -</p> -</dd> -</dl> - - -<a name="See-Also"></a> -<h2 class="chapter">5 See Also<span class="pull-right"><a class="anchor hidden-xs" href="#See-Also" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-See-Also" aria-hidden="true">TOC</a></span></h2> - -<p><a href="ffmpeg.html">ffmpeg</a>, <a href="ffplay.html">ffplay</a>, <a href="ffprobe.html">ffprobe</a>, <a href="ffserver.html">ffserver</a>, -<a href="libavutil.html">libavutil</a> -</p> - -<a name="Authors"></a> -<h2 class="chapter">6 Authors<span class="pull-right"><a class="anchor hidden-xs" href="#Authors" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Authors" aria-hidden="true">TOC</a></span></h2> - -<p>The FFmpeg developers. -</p> -<p>For details about the authorship, see the Git history of the project -(git://source.ffmpeg.org/ffmpeg), e.g. by typing the command -<code>git log</code> in the FFmpeg source directory, or browsing the -online repository at <a href="http://source.ffmpeg.org">http://source.ffmpeg.org</a>. -</p> -<p>Maintainers for the specific components are listed in the file -<samp>MAINTAINERS</samp> in the source code tree. -</p> - - - <p style="font-size: small;"> - This document was generated using <a href="http://www.gnu.org/software/texinfo/"><em>makeinfo</em></a>. - </p> - </div> - </body> -</html> |