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Bring in flac, ogg, vorbis
author Chris Cannam
date Tue, 19 Mar 2013 17:37:49 +0000
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/libvorbis-1.3.3/doc/vorbisenc/examples.html	Tue Mar 19 17:37:49 2013 +0000
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+<html>
+
+<head>
+<title>libvorbisenc - Documentation</title>
+<link rel=stylesheet href="style.css" type="text/css">
+</head>
+
+<body bgcolor=white text=black link="#5555ff" alink="#5555ff" vlink="#5555ff">
+<table border=0 width=100%>
+<tr>
+<td><p class=tiny>libvorbisenc documentation</p></td>
+<td align=right><p class=tiny>libvorbisenc version 1.3.2 - 20101101</p></td>
+</tr>
+</table>
+
+<h1>Libvorbisenc Setup Examples</h1>
+
+VBR is always the recommended mode for Vorbis encoding when
+there's no need to impose bitrate constraints.  True VBR encoding will
+always produce the most consistent quality output as well as the
+highest quality for a the bits used. 
+
+<p>The following code examples prepare a
+<a href="../libvorbis/vorbis_info.html">vorbis_info</a> structure for encoding
+use with libvorbis.<p>
+
+<h2>Example: encoding using a VBR quality mode</h2>
+
+<table border=0 width=100% color=black cellspacing=0 cellpadding=7>
+<tr bgcolor=#cccccc><td><pre><b> 
+   vorbis_info_init(&vi);
+
+  /*********************************************************************
+   Encoding using a VBR quality mode.  The usable range is -.1
+   (lowest quality, smallest file) to 1.0 (highest quality, largest file).
+   Example quality mode .4: 44kHz stereo coupled, roughly 128kbps VBR 
+   *********************************************************************/
+  
+   ret = vorbis_encode_init_vbr(&vi,2,44100,.4);
+
+  /*********************************************************************
+   do not continue if setup failed; this can happen if we ask for a
+   mode that libVorbis does not support (eg, too low a quality mode, etc,
+   will return 'OV_EIMPL')
+   *********************************************************************/
+
+   if(ret) exit(1);
+</b></pre></td></tr></table>
+
+<h2>Example: encoding using average bitrate (ABR)</h2>
+
+<table border=0 width=100% color=black cellspacing=0 cellpadding=7>
+<tr bgcolor=#cccccc><td><pre><b> 
+   vorbis_info_init(&vi);
+
+  /*********************************************************************
+   Encoding using an average bitrate mode (ABR).
+   example: 44kHz stereo coupled, average 128kbps ABR 
+   *********************************************************************/
+  
+   ret = vorbis_encode_init(&vi,2,44100,-1,128000,-1);
+
+  /*********************************************************************
+   do not continue if setup failed; this can happen if we ask for a
+   mode that libVorbis does not support (eg, too low a bitrate, etc,
+   will return 'OV_EIMPL')
+   *********************************************************************/
+
+   if(ret) exit(1);
+</b></pre></td></tr></table>
+
+<h2>Example: encoding using constant bitrate (CBR)</h2>
+
+<table border=0 width=100% color=black cellspacing=0 cellpadding=7>
+<tr bgcolor=#cccccc><td><pre><b> 
+   vorbis_info_init(&vi);
+
+  /*********************************************************************
+   Encoding using a constant bitrate mode (CBR).
+   example: 44kHz stereo coupled, average 128kbps CBR 
+   *********************************************************************/
+  
+   ret = vorbis_encode_init(&vi,2,44100,128000,128000,128000);
+
+  /*********************************************************************
+   do not continue if setup failed; this can happen if we ask for a
+   mode that libVorbis does not support (eg, too low a bitrate, etc,
+   will return 'OV_EIMPL')
+   *********************************************************************/
+
+   if(ret) exit(1);
+</b></pre></td></tr></table>
+
+<h2>Example: encoding using VBR selected by approximate bitrate</h2>
+
+<table border=0 width=100% color=black cellspacing=0 cellpadding=7>
+<tr bgcolor=#cccccc><td><pre><b> 
+   vorbis_info_init(&vi);
+
+  /*********************************************************************
+   Encode using a quality mode, but select that quality mode by asking for
+   an approximate bitrate.  This is not ABR, it is true VBR, but selected
+   using the bitrate interface, and then turning bitrate management off:
+   *********************************************************************/
+
+   ret = ( vorbis_encode_setup_managed(&vi,2,44100,-1,128000,-1) ||
+           vorbis_encode_ctl(&vi,OV_ECTL_RATEMANAGE2_SET,NULL) ||
+           vorbis_encode_setup_init(&vi));
+
+  /*********************************************************************
+   do not continue if setup failed; this can happen if we ask for a
+   mode that libVorbis does not support (eg, too low a bitrate, etc,
+   will return 'OV_EIMPL')
+   *********************************************************************/
+
+   if(ret) exit(1);
+</b></pre></td></tr></table>
+
+<br><br>
+<hr noshade>
+<table border=0 width=100%>
+<tr valign=top>
+<td><p class=tiny>copyright &copy; 2000-2010 Xiph.Org</p></td>
+<td align=right><p class=tiny><a href="http://www.xiph.org/ogg/vorbis/">Ogg Vorbis</a></p></td>
+</tr><tr>
+<td><p class=tiny>libvorbisenc documentation</p></td>
+<td align=right><p class=tiny>libvorbisenc version 1.3.2 - 20101101</p></td>
+</tr>
+</table>
+
+</body>
+
+</html>