Edit File: ffmpeg-scaler.html
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> <head> <meta charset="utf-8"> <title> FFmpeg Scaler 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 style="width: 95%; margin: auto"> <h1> FFmpeg Scaler 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-Scaler-Options" href="#Scaler-Options">2 Scaler Options</a></li> <li><a name="toc-See-Also" href="#See-Also">3 See Also</a></li> <li><a name="toc-Authors" href="#Authors">4 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>The FFmpeg rescaler provides a high-level interface to the libswscale library image conversion utilities. In particular it allows one to perform image rescaling and pixel format conversion. </p> <a name="scaler_005foptions"></a><a name="Scaler-Options"></a> <h2 class="chapter">2 Scaler Options<span class="pull-right"><a class="anchor hidden-xs" href="#Scaler-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Scaler-Options" aria-hidden="true">TOC</a></span></h2> <p>The video scaler supports the following named options. </p> <p>Options may be set by specifying -<var>option</var> <var>value</var> in the FFmpeg tools. For programmatic use, they can be set explicitly in the <code>SwsContext</code> options or through the <samp>libavutil/opt.h</samp> API. </p> <dl compact="compact"> <dd> <a name="sws_005fflags"></a></dd> <dt><samp>sws_flags</samp></dt> <dd><p>Set the scaler flags. This is also used to set the scaling algorithm. Only a single algorithm should be selected. </p> <p>It accepts the following values: </p><dl compact="compact"> <dt>‘<samp>fast_bilinear</samp>’</dt> <dd><p>Select fast bilinear scaling algorithm. </p> </dd> <dt>‘<samp>bilinear</samp>’</dt> <dd><p>Select bilinear scaling algorithm. </p> </dd> <dt>‘<samp>bicubic</samp>’</dt> <dd><p>Select bicubic scaling algorithm. </p> </dd> <dt>‘<samp>experimental</samp>’</dt> <dd><p>Select experimental scaling algorithm. </p> </dd> <dt>‘<samp>neighbor</samp>’</dt> <dd><p>Select nearest neighbor rescaling algorithm. </p> </dd> <dt>‘<samp>area</samp>’</dt> <dd><p>Select averaging area rescaling algorithm. </p> </dd> <dt>‘<samp>bicublin</samp>’</dt> <dd><p>Select bicubic scaling algorithm for the luma component, bilinear for chroma components. </p> </dd> <dt>‘<samp>gauss</samp>’</dt> <dd><p>Select Gaussian rescaling algorithm. </p> </dd> <dt>‘<samp>sinc</samp>’</dt> <dd><p>Select sinc rescaling algorithm. </p> </dd> <dt>‘<samp>lanczos</samp>’</dt> <dd><p>Select lanczos rescaling algorithm. </p> </dd> <dt>‘<samp>spline</samp>’</dt> <dd><p>Select natural bicubic spline rescaling algorithm. </p> </dd> <dt>‘<samp>print_info</samp>’</dt> <dd><p>Enable printing/debug logging. </p> </dd> <dt>‘<samp>accurate_rnd</samp>’</dt> <dd><p>Enable accurate rounding. </p> </dd> <dt>‘<samp>full_chroma_int</samp>’</dt> <dd><p>Enable full chroma interpolation. </p> </dd> <dt>‘<samp>full_chroma_inp</samp>’</dt> <dd><p>Select full chroma input. </p> </dd> <dt>‘<samp>bitexact</samp>’</dt> <dd><p>Enable bitexact output. </p></dd> </dl> </dd> <dt><samp>srcw</samp></dt> <dd><p>Set source width. </p> </dd> <dt><samp>srch</samp></dt> <dd><p>Set source height. </p> </dd> <dt><samp>dstw</samp></dt> <dd><p>Set destination width. </p> </dd> <dt><samp>dsth</samp></dt> <dd><p>Set destination height. </p> </dd> <dt><samp>src_format</samp></dt> <dd><p>Set source pixel format (must be expressed as an integer). </p> </dd> <dt><samp>dst_format</samp></dt> <dd><p>Set destination pixel format (must be expressed as an integer). </p> </dd> <dt><samp>src_range</samp></dt> <dd><p>Select source range. </p> </dd> <dt><samp>dst_range</samp></dt> <dd><p>Select destination range. </p> </dd> <dt><samp>param0, param1</samp></dt> <dd><p>Set scaling algorithm parameters. The specified values are specific of some scaling algorithms and ignored by others. The specified values are floating point number values. </p> </dd> <dt><samp>sws_dither</samp></dt> <dd><p>Set the dithering algorithm. Accepts one of the following values. Default value is ‘<samp>auto</samp>’. </p> <dl compact="compact"> <dt>‘<samp>auto</samp>’</dt> <dd><p>automatic choice </p> </dd> <dt>‘<samp>none</samp>’</dt> <dd><p>no dithering </p> </dd> <dt>‘<samp>bayer</samp>’</dt> <dd><p>bayer dither </p> </dd> <dt>‘<samp>ed</samp>’</dt> <dd><p>error diffusion dither </p> </dd> <dt>‘<samp>a_dither</samp>’</dt> <dd><p>arithmetic dither, based using addition </p> </dd> <dt>‘<samp>x_dither</samp>’</dt> <dd><p>arithmetic dither, based using xor (more random/less apparent patterning that a_dither). </p> </dd> </dl> </dd> <dt><samp>alphablend</samp></dt> <dd><p>Set the alpha blending to use when the input has alpha but the output does not. Default value is ‘<samp>none</samp>’. </p> <dl compact="compact"> <dt>‘<samp>uniform_color</samp>’</dt> <dd><p>Blend onto a uniform background color </p> </dd> <dt>‘<samp>checkerboard</samp>’</dt> <dd><p>Blend onto a checkerboard </p> </dd> <dt>‘<samp>none</samp>’</dt> <dd><p>No blending </p> </dd> </dl> </dd> </dl> <a name="See-Also"></a> <h2 class="chapter">3 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="libswscale.html">libswscale</a> </p> <a name="Authors"></a> <h2 class="chapter">4 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>