From 74f4b1bc3b627ba4c7e03498234d88cacdfbe97b Mon Sep 17 00:00:00 2001 From: Aki Date: Wed, 29 Sep 2021 22:52:49 +0200 Subject: Squashed 'vorbis/' content from commit d22c3ab5f git-subtree-dir: vorbis git-subtree-split: d22c3ab5f633460abc2532feee60ca0892134cbf --- doc/vorbisenc/examples.html | 133 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 133 insertions(+) create mode 100644 doc/vorbisenc/examples.html (limited to 'doc/vorbisenc/examples.html') diff --git a/doc/vorbisenc/examples.html b/doc/vorbisenc/examples.html new file mode 100644 index 0000000..1fcc7e0 --- /dev/null +++ b/doc/vorbisenc/examples.html @@ -0,0 +1,133 @@ + + + +libvorbisenc - Documentation + + + + + + + + + +

libvorbisenc documentation

libvorbisenc version 1.3.2 - 20101101

+ +

Libvorbisenc Setup Examples

+ +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. + +

The following code examples prepare a +vorbis_info structure for encoding +use with libvorbis.

+ +

Example: encoding using a VBR quality mode

+ + +
 
+   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);
+
+ +

Example: encoding using average bitrate (ABR)

+ + +
 
+   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);
+
+ +

Example: encoding using constant bitrate (CBR)

+ + +
 
+   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);
+
+ +

Example: encoding using VBR selected by approximate bitrate

+ + +
 
+   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);
+
+ +

+
+ + + + + + + + +

copyright © 2000-2010 Xiph.Org

Ogg Vorbis

libvorbisenc documentation

libvorbisenc version 1.3.2 - 20101101

+ + + + -- cgit v1.1