<section id="vorbis-spec-intro">
<sectioninfo>
<releaseinfo>
- $Id: 01-introduction.xml,v 1.6 2002/10/27 15:05:51 giles Exp $
+ $Id: 01-introduction.xml,v 1.7 2002/10/27 16:20:47 giles Exp $
<emphasis>Last update to this document: July 18, 2002</emphasis>
</releaseinfo>
</sectioninfo>
-<title>introduction and description</title>
+<title>Introduction and Description</title>
<section>
<title>Overview</title>
<para>
This document provides a high level description of the Vorbis codec's
-construction. A bit-by-bit specification appears beginning in <xref linkend="vorbis-spec-codec"/>.
+construction. A bit-by-bit specification appears beginning in
+<xref linkend="vorbis-spec-codec"/>.
The later sections assume a high-level
understanding of the Vorbis decode process, which is
provided here.</para>
<title>High-level Decode Process</title>
<section>
-<title>Decode setup</title>
+<title>Decode Setup</title>
<para>
Before decoding can begin, a decoder must initialize using the
<section id="vorbis-spec-bitpacking">
<sectioninfo>
<releaseinfo>
- $Id: 02-bitpacking.xml,v 1.5 2002/10/27 14:55:31 giles Exp $
+ $Id: 02-bitpacking.xml,v 1.6 2002/10/27 16:20:47 giles Exp $
<emphasis>Last update to this document: July 14, 2002</emphasis>
</releaseinfo>
</sectioninfo>
-<title>bitpacking convention</title>
+<title>Bitpacking Convention</title>
<section>
<section id="vorbis-spec-codebook">
<sectioninfo>
<releaseinfo>
- $Id: 03-codebook.xml,v 1.4 2002/10/27 14:55:31 giles Exp $
+ $Id: 03-codebook.xml,v 1.5 2002/10/27 16:20:47 giles Exp $
<emphasis>Last update to this document: August 8, 2002</emphasis>
</releaseinfo>
</sectioninfo>
-<title>probability model and codebooks</title>
+<title>Probability Model and Codebooks</title>
<section>
<title>Overview</title>
decoded Huffman value is applied as an offset, generating the final
decoded output corresponding to a given compressed codeword.</para>
-<section><title>bitwise operation</title>
+<section><title>Bitwise operation</title>
<para>
The codebook mechanism is built on top of the vorbis bitpacker. Both
the codebooks themselves and the codewords they decode are unrolled
</section>
<section>
-<title>Packed Codebook Format</title>
+<title>Packed codebook format</title>
<para>
For purposes of the examples below, we assume that the storage
<section id="vorbis-spec-codec">
<sectioninfo>
<releaseinfo>
- $Id: 04-codec.xml,v 1.6 2002/10/27 14:55:31 giles Exp $
+ $Id: 04-codec.xml,v 1.7 2002/10/27 16:20:47 giles Exp $
<emphasis>Last update to this document: October 15, 2002</emphasis>
</releaseinfo>
</sectioninfo>
-<title>codec setup and packet decode</title>
+<title>Codec Setup and Packet Decode</title>
<section>
<title>Overview</title>
This document serves as the top-level reference document for the
bit-by-bit decode specification of Vorbis I. This document assumes a
high-level understanding of the Vorbis decode process, which is
-provided in the section <xref linkend="vorbis-spec-intro"/>. <xref
+provided in <xref linkend="vorbis-spec-intro"/>. <xref
linkend="vorbis-spec-bitpacking"/> covers reading and writing bit fields from
and to bitstream packets.</para>
</section>
-<section><title>Identification Header</title>
+<section><title>Identification header</title>
<para>
The identification header is a short header of only a few fields used
</section>
-<section><title>Comment Header</title>
+<section><title>Comment header</title>
<para>
Comment header decode and data specification is covered in
<xref linkend="vorbis-spec-comment"/>.</para>
</section>
-<section><title>Setup Header</title>
+<section><title>Setup header</title>
<para>
Vorbis codec setup is configurable to an extreme degree:
configurations. It finishes with a framing bit of '1'. Header decode
proceeds in the following order:</para>
-<section><title>codebooks</title>
+<section><title>Codebooks</title>
<orderedlist>
<listitem><simpara><varname>[vorbis_codebook_count]</varname> = read eight bits as unsigned integer and add one</simpara></listitem>
</section>
-<section><title>time domain transforms</title>
+<section><title>Time domain transforms</title>
<para>
These hooks are placeholders in Vorbis I. Nevertheless, the
</section>
-<section><title>floors</title>
+<section><title>Floors</title>
<para>
Vorbis uses two floor types; header decode is handed to the decode
</section>
-<section><title>residues</title>
+<section><title>Residues</title>
<para>
Vorbis uses three residue types; header decode of each type is identical.
</section>
-<section><title>mappings</title>
+<section><title>Mappings</title>
<para>
Mappings are used to set up specific pipelines for encoding
</section>
-<section><title>modes</title>
+<section><title>Modes</title>
<orderedlist>
<listitem><simpara><varname>[vorbis_mode_count]</varname> = read 6 bits as unsigned integer and add one</simpara></listitem>
<section id="vorbis-spec-floor0">
<sectioninfo>
<releaseinfo>
- $Id: 06-floor0.xml,v 1.6 2002/10/27 14:55:31 giles Exp $
+ $Id: 06-floor0.xml,v 1.7 2002/10/27 16:20:47 giles Exp $
<emphasis>Last update to this document: July 19, 2002</emphasis>
</releaseinfo>
</sectioninfo>
-<title>floor type 0 setup and decode</title>
+<title>Floor type 0 setup and decode</title>
<section>
<section id="vorbis-spec-floor1">
<sectioninfo>
<releaseinfo>
- $Id: 07-floor1.xml,v 1.3 2002/10/27 14:55:31 giles Exp $
+ $Id: 07-floor1.xml,v 1.4 2002/10/27 16:20:47 giles Exp $
<emphasis>Last update to this document: October 15, 2002</emphasis>
</releaseinfo>
</sectioninfo>
-<title>floor type 1 setup and decode</title>
+<title>Floor type 1 setup and decode</title>
<section>
<title>Overview</title>
<section id="vorbis-spec-residue">
<sectioninfo>
<releaseinfo>
- $Id: 08-residue.xml,v 1.3 2002/10/27 14:55:31 giles Exp $
+ $Id: 08-residue.xml,v 1.4 2002/10/27 16:20:47 giles Exp $
<emphasis>Last update to this document: July 19, 2002</emphasis>
</releaseinfo>
</sectioninfo>
-<title>residue setup and decode</title>
+<title>Residue setup and decode</title>
<section>
</section>
-<section><title> residue 1 </title>
+<section><title>residue 1</title>
<para>
Residue 1 does not interleave VQ encoding. It represents partition
</section>
-<section><title> residue 2 </title>
+<section><title>residue 2</title>
<para>
Residue type two can be thought of as a variant of residue type 1.
<section id="vorbis-spec-helper">
<sectioninfo>
<releaseinfo>
- $Id: 09-helper.xml,v 1.4 2002/10/27 14:55:31 giles Exp $
+ $Id: 09-helper.xml,v 1.5 2002/10/27 16:20:47 giles Exp $
<emphasis>Last update to this document: October 15, 2002</emphasis>
</releaseinfo>
</sectioninfo>
-<title>helper equations</title>
+<title>Helper equations</title>
<section>
<title>Overview</title>