<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>scaletempo</title>
<meta name="generator" content="DocBook XSL Stylesheets V1.75.2">
<link rel="home" href="index.html" title="GStreamer Bad Plugins 0.10 Plugins Reference Manual">
<link rel="up" href="ch01.html" title="gst-plugins-bad Elements">
<link rel="prev" href="gst-plugins-bad-plugins-rtpmux.html" title="rtpmux">
<link rel="next" href="gst-plugins-bad-plugins-sdlaudiosink.html" title="sdlaudiosink">
<meta name="generator" content="GTK-Doc V1.11 (XML mode)">
<link rel="stylesheet" href="style.css" type="text/css">
<link rel="chapter" href="ch01.html" title="gst-plugins-bad Elements">
<link rel="chapter" href="ch02.html" title="gst-plugins-bad Plugins">
<link rel="chapter" href="ch03.html" title="gst-plugins-bad Classes">
</head>
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
<table class="navigation" id="top" width="100%" summary="Navigation header" cellpadding="2" cellspacing="2">
<tr valign="middle">
<td><a accesskey="p" href="gst-plugins-bad-plugins-rtpmux.html"><img src="left.png" width="24" height="24" border="0" alt="Prev"></a></td>
<td><a accesskey="u" href="ch01.html"><img src="up.png" width="24" height="24" border="0" alt="Up"></a></td>
<td><a accesskey="h" href="index.html"><img src="home.png" width="24" height="24" border="0" alt="Home"></a></td>
<th width="100%" align="center">GStreamer Bad Plugins 0.10 Plugins Reference Manual</th>
<td><a accesskey="n" href="gst-plugins-bad-plugins-sdlaudiosink.html"><img src="right.png" width="24" height="24" border="0" alt="Next"></a></td>
</tr>
<tr><td colspan="5" class="shortcuts">
<a href="#gst-plugins-bad-plugins-scaletempo.synopsis" class="shortcut">Top</a>
|
<a href="#gst-plugins-bad-plugins-scaletempo.description" class="shortcut">Description</a>
|
<a href="#gst-plugins-bad-plugins-scaletempo.object-hierarchy" class="shortcut">Object Hierarchy</a>
|
<a href="#gst-plugins-bad-plugins-scaletempo.properties" class="shortcut">Properties</a>
</td></tr>
</table>
<div class="refentry" title="scaletempo">
<a name="gst-plugins-bad-plugins-scaletempo"></a><div class="titlepage"></div>
<div class="refnamediv"><table width="100%"><tr>
<td valign="top">
<h2><span class="refentrytitle"><a name="gst-plugins-bad-plugins-scaletempo.top_of_page"></a>scaletempo</span></h2>
<p>scaletempo — Sync audio tempo with playback rate</p>
</td>
<td valign="top" align="right"></td>
</tr></table></div>
<div class="refsynopsisdiv" title="Synopsis">
<a name="gst-plugins-bad-plugins-scaletempo.synopsis"></a><h2>Synopsis</h2>
<a name="GstScaletempo"></a><pre class="synopsis">
<a class="link" href="gst-plugins-bad-plugins-scaletempo.html#GstScaletempo-struct" title="GstScaletempo">GstScaletempo</a>;
</pre>
</div>
<div class="refsect1" title="Object Hierarchy">
<a name="gst-plugins-bad-plugins-scaletempo.object-hierarchy"></a><h2>Object Hierarchy</h2>
<pre class="synopsis">
<a
href="/usr/share/gtk-doc/html/gobject/gobject-The-Base-Object-Type.html#GObject"
>GObject</a>
+----<a
href="/usr/share/gtk-doc/html/gstreamer-0.10/GstObject.html"
>GstObject</a>
+----<a
href="/usr/share/gtk-doc/html/gstreamer-0.10/GstElement.html"
>GstElement</a>
+----<a
href="/usr/share/gtk-doc/html/gstreamer-libs-0.10/GstBaseTransform.html"
>GstBaseTransform</a>
+----GstScaletempo
</pre>
</div>
<div class="refsect1" title="Properties">
<a name="gst-plugins-bad-plugins-scaletempo.properties"></a><h2>Properties</h2>
<pre class="synopsis">
"<a class="link" href="gst-plugins-bad-plugins-scaletempo.html#GstScaletempo--overlap" title='The "overlap" property'>overlap</a>" <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gdouble"
>gdouble</a> : Read / Write
"<a class="link" href="gst-plugins-bad-plugins-scaletempo.html#GstScaletempo--rate" title='The "rate" property'>rate</a>" <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gdouble"
>gdouble</a> : Read
"<a class="link" href="gst-plugins-bad-plugins-scaletempo.html#GstScaletempo--search" title='The "search" property'>search</a>" <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint"
>guint</a> : Read / Write
"<a class="link" href="gst-plugins-bad-plugins-scaletempo.html#GstScaletempo--stride" title='The "stride" property'>stride</a>" <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint"
>guint</a> : Read / Write
</pre>
</div>
<div class="refsect1" title="Description">
<a name="gst-plugins-bad-plugins-scaletempo.description"></a><h2>Description</h2>
<p>
</p>
<div class="refsect2" title="Example pipelines">
<a name="id514792"></a><h3>Example pipelines</h3>
<p>
Scale tempo while maintaining pitch
(WSOLA-like technique with cross correlation)
Inspired by SoundTouch library by Olli Parviainen
</p>
<p>
Use Sceletempo to apply playback rates without the chipmunk effect.
</p>
<p>
</p>
<pre class="programlisting">
filesrc location=media.ext ! decodebin name=d \
d. ! queue ! audioconvert ! audioresample ! scaletempo ! audioconvert ! audioresample ! autoaudiosink \
d. ! queue ! ffmpegcolorspace ! autovideosink
</pre>
<p>
OR
</p>
<pre class="programlisting">
playbin uri=... audio_sink="scaletempo ! audioconvert ! audioresample ! autoaudiosink"
</pre>
<p>
When an application sends a seek event with rate != 1.0, Scaletempo applies
the rate change by scaling the tempo without scaling the pitch.
</p>
<p>
Scaletempo works by producing audio in constant sized chunks (a "stride") but
consuming chunks proportional to the playback rate.
</p>
<p>
Scaletempo then smooths the output by blending the end of one stride with
the next ("overlap").
</p>
<p>
Scaletempo smooths the overlap further by searching within the input buffer
for the best overlap position. Scaletempo uses a statistical cross correlation
(roughly a dot-product). Scaletempo consumes most of its CPU cycles here.
</p>
</div>
<div class="refsynopsisdiv" title="Synopsis">
<h2>Synopsis</h2>
<div class="refsect2" title="Element Information">
<a name="id514636"></a><h3>Element Information</h3>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term">plugin</span></p></td>
<td>
<a class="link" href="gst-plugins-bad-plugins-plugin-scaletempo.html#plugin-scaletempo">scaletempo</a>
</td>
</tr>
<tr>
<td><p><span class="term">author</span></p></td>
<td>Rov Juvano <rovjuvano@users.sourceforge.net></td>
</tr>
<tr>
<td><p><span class="term">class</span></p></td>
<td>Filter/Effect/Rate</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" title="Element Pads">
<a name="id514698"></a><h3>Element Pads</h3>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term">name</span></p></td>
<td>sink</td>
</tr>
<tr>
<td><p><span class="term">direction</span></p></td>
<td>sink</td>
</tr>
<tr>
<td><p><span class="term">presence</span></p></td>
<td>always</td>
</tr>
<tr>
<td><p><span class="term">details</span></p></td>
<td>audio/x-raw-float, rate=(int)[ 1, 2147483647 ], channels=(int)[ 1, 2147483647 ], endianness=(int)1234, width=(int)32</td>
</tr>
<tr>
<td><p><span class="term"></span></p></td>
<td> audio/x-raw-int, rate=(int)[ 1, 2147483647 ], channels=(int)[ 1, 2147483647 ], endianness=(int)1234, width=(int)16, depth=(int)16, signed=(boolean)true</td>
</tr>
</tbody>
</table></div>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term">name</span></p></td>
<td>src</td>
</tr>
<tr>
<td><p><span class="term">direction</span></p></td>
<td>source</td>
</tr>
<tr>
<td><p><span class="term">presence</span></p></td>
<td>always</td>
</tr>
<tr>
<td><p><span class="term">details</span></p></td>
<td>audio/x-raw-float, rate=(int)[ 1, 2147483647 ], channels=(int)[ 1, 2147483647 ], endianness=(int)1234, width=(int)32</td>
</tr>
<tr>
<td><p><span class="term"></span></p></td>
<td> audio/x-raw-int, rate=(int)[ 1, 2147483647 ], channels=(int)[ 1, 2147483647 ], endianness=(int)1234, width=(int)16, depth=(int)16, signed=(boolean)true</td>
</tr>
</tbody>
</table></div>
</div>
</div>
<p>
</p>
</div>
<div class="refsect1" title="Details">
<a name="gst-plugins-bad-plugins-scaletempo.details"></a><h2>Details</h2>
<div class="refsect2" title="GstScaletempo">
<a name="GstScaletempo-struct"></a><h3>GstScaletempo</h3>
<pre class="programlisting">typedef struct _GstScaletempo GstScaletempo;</pre>
<p>
</p>
</div>
</div>
<div class="refsect1" title="Property Details">
<a name="gst-plugins-bad-plugins-scaletempo.property-details"></a><h2>Property Details</h2>
<div class="refsect2" title='The "overlap" property'>
<a name="GstScaletempo--overlap"></a><h3>The <code class="literal">"overlap"</code> property</h3>
<pre class="programlisting"> "overlap" <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gdouble"
>gdouble</a> : Read / Write</pre>
<p>Percentage of stride to overlap.</p>
<p>Allowed values: [0,1]</p>
<p>Default value: 0.2</p>
</div>
<hr>
<div class="refsect2" title='The "rate" property'>
<a name="GstScaletempo--rate"></a><h3>The <code class="literal">"rate"</code> property</h3>
<pre class="programlisting"> "rate" <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gdouble"
>gdouble</a> : Read</pre>
<p>Current playback rate.</p>
<p>Allowed values: [-2.14748e+09,2.14748e+09]</p>
<p>Default value: 1</p>
</div>
<hr>
<div class="refsect2" title='The "search" property'>
<a name="GstScaletempo--search"></a><h3>The <code class="literal">"search"</code> property</h3>
<pre class="programlisting"> "search" <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint"
>guint</a> : Read / Write</pre>
<p>Length in milliseconds to search for best overlap position.</p>
<p>Allowed values: <= 500</p>
<p>Default value: 14</p>
</div>
<hr>
<div class="refsect2" title='The "stride" property'>
<a name="GstScaletempo--stride"></a><h3>The <code class="literal">"stride"</code> property</h3>
<pre class="programlisting"> "stride" <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint"
>guint</a> : Read / Write</pre>
<p>Length in milliseconds to output each stride.</p>
<p>Allowed values: [1,5000]</p>
<p>Default value: 30</p>
</div>
</div>
</div>
<div class="footer">
<hr>
Generated by GTK-Doc V1.11</div>
</body>
</html>
distrib
>
Mandriva
>
2010.0
>
i586
>
media
>
contrib-release
>
by-pkgid
>
c918544921e88c4bd8b7047de18a345b
>
files
>
134
