codekingpro/portable-devtools

1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">2<html>3<!-- Created by , GNU Texinfo 7.1.1 -->4  <head>5    <meta charset="utf-8">6    <title>7      Libswresample Documentation8    </title>9    <meta name="viewport" content="width=device-width,initial-scale=1.0">10    <link rel="stylesheet" type="text/css" href="bootstrap.min.css">11    <link rel="stylesheet" type="text/css" href="style.min.css">12  </head>13  <body>14    <div class="container">15      <h1>16      Libswresample Documentation17      </h1>18 19 20<a name="SEC_Top"></a>21 22<div class="element-contents" id="SEC_Contents">23<h2 class="contents-heading">Table of Contents</h2>24 25<div class="contents">26 27<ul class="toc-numbered-mark">28  <li><a id="toc-Description" href="#Description">1 Description</a></li>29  <li><a id="toc-See-Also" href="#See-Also">2 See Also</a></li>30  <li><a id="toc-Authors" href="#Authors">3 Authors</a></li>31</ul>32</div>33</div>34 35<a name="Description"></a>36<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>37 38<p>The libswresample library performs highly optimized audio resampling,39rematrixing and sample format conversion operations.40</p>41<p>Specifically, this library performs the following conversions:42</p>43<ul class="itemize mark-bullet">44<li><em class="emph">Resampling</em>: is the process of changing the audio rate, for45example from a high sample rate of 44100Hz to 8000Hz. Audio46conversion from high to low sample rate is a lossy process. Several47resampling options and algorithms are available.48 49</li><li><em class="emph">Format conversion</em>: is the process of converting the type of50samples, for example from 16-bit signed samples to unsigned 8-bit or51float samples. It also handles packing conversion, when passing from52packed layout (all samples belonging to distinct channels interleaved53in the same buffer), to planar layout (all samples belonging to the54same channel stored in a dedicated buffer or &quot;plane&quot;).55 56</li><li><em class="emph">Rematrixing</em>: is the process of changing the channel layout, for57example from stereo to mono. When the input channels cannot be mapped58to the output streams, the process is lossy, since it involves59different gain factors and mixing.60</li></ul>61 62<p>Various other audio conversions (e.g. stretching and padding) are63enabled through dedicated options.64</p>65 66<a name="See-Also"></a>67<h2 class="chapter">2 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>68 69<p><a class="url" href="ffmpeg.html">ffmpeg</a>, <a class="url" href="ffplay.html">ffplay</a>, <a class="url" href="ffprobe.html">ffprobe</a>,70<a class="url" href="ffmpeg-resampler.html">ffmpeg-resampler</a>,71<a class="url" href="libavutil.html">libavutil</a>72</p>73 74<a name="Authors"></a>75<h2 class="chapter">3 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>76 77<p>The FFmpeg developers.78</p>79<p>For details about the authorship, see the Git history of the project80(https://git.ffmpeg.org/ffmpeg), e.g. by typing the command81<code class="command">git log</code> in the FFmpeg source directory, or browsing the82online repository at <a class="url" href="https://git.ffmpeg.org/ffmpeg">https://git.ffmpeg.org/ffmpeg</a>.83</p>84<p>Maintainers for the specific components are listed in the file85<samp class="file">MAINTAINERS</samp> in the source code tree.86</p>87 88      <p style="font-size: small;">89        This document was generated using <a class="uref" href="https://www.gnu.org/software/texinfo/"><em class="emph">makeinfo</em></a>.90      </p>91    </div>92  </body>93</html>94