[xiph-cvs] cvs commit: vorbis/doc/xml 04-codec.xml 07-floor1.xml Vorbis_I_spec.xml
Ralph Giles
giles at xiph.org
Thu Oct 17 17:43:00 PDT 2002
giles 02/10/17 20:43:00
Modified: doc/xml 04-codec.xml 07-floor1.xml Vorbis_I_spec.xml
Log:
Propagate documentation updates from the html version.
Revision Changes Path
1.3 +33 -45 vorbis/doc/xml/04-codec.xml
Index: 04-codec.xml
===================================================================
RCS file: /usr/local/cvsroot/vorbis/doc/xml/04-codec.xml,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -r1.2 -r1.3
--- 04-codec.xml 14 Oct 2002 23:47:54 -0000 1.2
+++ 04-codec.xml 18 Oct 2002 00:43:00 -0000 1.3
@@ -1,8 +1,8 @@
<section id="vorbis-spec-codec">
<sectioninfo>
<releaseinfo>
- $Id: 04-codec.xml,v 1.2 2002/10/14 23:47:54 giles Exp $
- <emphasis>Last update to this document: September 20, 2002</emphasis>
+ $Id: 04-codec.xml,v 1.3 2002/10/18 00:43:00 giles Exp $
+ <emphasis>Last update to this document: October 15, 2002</emphasis>
</releaseinfo>
</sectioninfo>
<title>codec setup and packet decode</title>
@@ -220,53 +220,40 @@
<listitem><simpara>if unset, <varname>[vorbis_mapping_submaps]</varname> = 1</simpara></listitem>
</orderedlist>
</listitem>
- <listitem><simpara>read 1 bit as a boolean flag; if set, square polar channel mapping is in use:</simpara>
- <orderedlist>
- <listitem><simpara><varname>[vorbis_mapping_coupling_steps]</varname>= read 8 bits as unsigned integer and add one</simpara></listitem>
- <listitem><simpara>for <varname>[j]</varname> each of <varname>[vorbis_mapping_coupling_steps]</varname>
-steps:</simpara>
- <orderedlist>
- <listitem><simpara>vector <varname>[vorbis_mapping_magnitude]</varname> element
-<varname>[j]</varname>= read <link linkend="vorbis-spec-ilog">ilog</link>([audio_channels] - 1) bits as
-unsigned integer</simpara></listitem>
- <listitem><simpara>vector <varname>[vorbis_mapping_angle]</varname> element <varname>[j]</varname>=
-read <link linkend="vorbis-spec-ilog">ilog</link>([audio_channels] - 1)
-bits as unsigned integer</simpara></listitem>
- <listitem><simpara>the numbers read in the above two steps are channel numbers representing the channel to treat as
-magnitude and the channel to treat as angle, respectively. If for any coupling step the angle channel number equals the
-magnitude channel number, the magnitude channel number is greater than <varname>[audio_channels]</varname>-1, or the angle
-channel is greater than <varname>[audio_channels]</varname>-1, the stream is undecodable.</simpara></listitem>
- </orderedlist>
- </listitem>
- </orderedlist>
+ <listitem><simpara>read 1 bit as a boolean flag</simpara>
+ <orderedlist>
+ <listitem><para>if set, square polar channel mapping is in use:
+ <orderedlist>
+ <listitem><simpara><varname>[vorbis_mapping_coupling_steps]</varname> = read 8 bits as unsigned integer and add one</simpara></listitem>
+ <listitem><para>for <varname>[j]</varname> each of <varname>[vorbis_mapping_coupling_steps]</varname> steps:
+ <orderedlist>
+ <listitem><simpara>vector <varname>[vorbis_mapping_magnitude]</varname> element <varname>[j]</varname>= read <link linkend="vorbis-spec-ilog">ilog</link>(<varname>[audio_channels]</varname> - 1) bits as unsigned integer</simpara></listitem>
+ <listitem><simpara>vector <varname>[vorbis_mapping_angle]</varname> element <varname>[j]</varname>= read <link linkend="vorbis-spec-ilog">ilog</link>(<varname>[audio_channels]</varname> - 1) bits as unsigned integer</simpara></listitem>
+ <listitem><simpara>the numbers read in the above two steps are channel numbers representing the channel to treat as magnitude and the channel to treat as angle, respectively. If for any coupling step the angle channel number equals the magnitude channel number, the magnitude channel number is greater than <varname>[audio_channels]</varname>-1, or the angle channel is greater than <varname>[audio_channels]</varname>-1, the stream is undecodable.</simpara></listitem>
+ </orderedlist>
+ </para></listitem>
+ </orderedlist>
+ </para></listitem>
+ <listitem><simpara>if unset, <varname>[vorbis_mapping_coupling_steps]</varname> = 0</simpara></listitem>
+ </orderedlist>
</listitem>
<listitem><simpara>read 2 bits (reserved field); if the value is nonzero, the stream is undecodable</simpara></listitem>
- <listitem><simpara>if <varname>[vorbis_mapping_submaps]</varname> is greater than one, we read channel multiplex
-settings. For each <varname>[j]</varname> of <varname>[audio_channels]</varname> channels:</simpara>
+ <listitem><simpara>if <varname>[vorbis_mapping_submaps]</varname> is greater than one, we read channel multiplex settings. For each <varname>[j]</varname> of <varname>[audio_channels]</varname> channels:</simpara>
<orderedlist>
- <listitem><simpara>vector <varname>[vorbis_mapping_mux]</varname> element <varname>[j]</varname> = read 4 bits as
-unsigned integer</simpara></listitem>
- <listitem><simpara>if the value is greater than the highest numbered submap
-(<varname>[vorbis_mapping_submaps]</varname> - 1), this in an error condition rendering the stream
-undecodable</simpara></listitem>
+ <listitem><simpara>vector <varname>[vorbis_mapping_mux]</varname> element <varname>[j]</varname> = read 4 bits as unsigned integer</simpara></listitem>
+ <listitem><simpara>if the value is greater than the highest numbered submap (<varname>[vorbis_mapping_submaps]</varname> - 1), this in an error condition rendering the stream undecodable</simpara></listitem>
</orderedlist>
</listitem>
- <listitem><simpara>for each submap <varname>[j]</varname> of <varname>[vorbis_mapping_submaps]</varname> submaps, read
-the floor and residue numbers for use in decoding that submap:</simpara>
+ <listitem><simpara>for each submap <varname>[j]</varname> of <varname>[vorbis_mapping_submaps]</varname> submaps, read the floor and residue numbers for use in decoding that submap:</simpara>
<orderedlist>
<listitem><simpara>read and discard 8 bits (the unused time configuration placeholder)</simpara></listitem>
- <listitem><simpara>read 8 bits as unsigned integer for the floor number; save in vector
-<varname>[vorbis_mapping_submap_floor]</varname> element <varname>[j]</varname></simpara></listitem>
- <listitem><simpara>verify the floor number is not greater than the highest number floor configured for the bitstream.
-If it is, the bitstream is undecodable</simpara></listitem>
- <listitem><simpara>read 8 bits as unsigned integer for the residue number; save in vector
-<varname>[vorbis_mapping_submap_residue]</varname> element <varname>[j]</varname></simpara></listitem>
- <listitem><simpara>verify the residue number is not greater than the highest number residue configured for the
-bitstream. If it is, the bitstream is undecodable</simpara></listitem>
+ <listitem><simpara>read 8 bits as unsigned integer for the floor number; save in vector <varname>[vorbis_mapping_submap_floor]</varname> element <varname>[j]</varname></simpara></listitem>
+ <listitem><simpara>verify the floor number is not greater than the highest number floor configured for the bitstream. If it is, the bitstream is undecodable</simpara></listitem>
+ <listitem><simpara>read 8 bits as unsigned integer for the residue number; save in vector <varname>[vorbis_mapping_submap_residue]</varname> element <varname>[j]</varname></simpara></listitem>
+ <listitem><simpara>verify the residue number is not greater than the highest number residue configured for the bitstream. If it is, the bitstream is undecodable</simpara></listitem>
</orderedlist>
</listitem>
- <listitem><simpara>save this mapping configuration in slot <varname>[i]</varname> of the mapping configuration array
-<varname>[vorbis_mapping_configurations]</varname>.</simpara></listitem>
+ <listitem><simpara>save this mapping configuration in slot <varname>[i]</varname> of the mapping configuration array <varname>[vorbis_mapping_configurations]</varname>.</simpara></listitem>
</orderedlist></para>
</listitem>
</orderedlist>
@@ -354,9 +341,10 @@
</orderedlist>
<para>
-Vorbis windows all use the slope function y=sin(2*PI*sin^2(x/n)),
-but dissimilar lapping requirements can affect overall shape. Window
-generation proceeds as follows:</para>
+Vorbis windows all use the slope function y=sin(0.5 * π * sin^2((x+.5)/n * π)),
+where n is window size and x ranges 0...n-1, but dissimilar
+lapping requirements can affect overall shape. Window generation
+proceeds as follows:</para>
<orderedlist>
<listitem><simpara> <varname>[window_center]</varname> = <varname>[n]</varname> / 2</simpara></listitem>
@@ -394,9 +382,9 @@
</listitem>
<listitem><simpara> window from range 0 ... <varname>[left_window_start]</varname>-1 inclusive is zero</simpara></listitem>
<listitem><simpara> for <varname>[i]</varname> in range <varname>[left_window_start]</varname> ...
-<varname>[left_window_end]</varname>-1, window(<varname>[i]</varname>) = sin(2*PI*sin^2((<varname>[i]</varname>-<varname>[left_window_start]</varname>+.5)/<varname>[left_n]</varname>*PI/2))</simpara></listitem>
+<varname>[left_window_end]</varname>-1, window(<varname>[i]</varname>) = sin(.5 * π * sin^2( (<varname>[i]</varname>-<varname>[left_window_start]</varname>+.5) / <varname>[left_n]</varname> * .5 * π) )</simpara></listitem>
<listitem><simpara> window from range <varname>[left_window_end]</varname> ... <varname>[right_window_start]</varname>-1
-inclusive is one</simpara></listitem><listitem><simpara> for <varname>[i]</varname> in range <varname>[right_window_start]</varname> ... <varname>[right_window_end]</varname>-1, window(<varname>[i]</varname>) = sin(2*PI*sin^2((<varname>[i]</varname>-<varname>[right_window_start]</varname>+.5)/<varname>[right_n]</varname>*PI/2.+PI/2.))</simpara></listitem>
+inclusive is one</simpara></listitem><listitem><simpara> for <varname>[i]</varname> in range <varname>[right_window_start]</varname> ... <varname>[right_window_end]</varname>-1, window(<varname>[i]</varname>) = sin(.5 * π * sin^2( (<varname>[i]</varname>-<varname>[right_window_start]</varname>+.5) / <varname>[right_n]</varname> * .5 * π/2. + .5 * π) )</simpara></listitem>
<listitem><simpara> window from range <varname>[rigth_window_start]</varname> ... <varname>[n]</varname>-1 is
zero</simpara></listitem>
</orderedlist>
<p><p>1.2 +11 -11 vorbis/doc/xml/07-floor1.xml
Index: 07-floor1.xml
===================================================================
RCS file: /usr/local/cvsroot/vorbis/doc/xml/07-floor1.xml,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- 07-floor1.xml 12 Oct 2002 20:37:11 -0000 1.1
+++ 07-floor1.xml 18 Oct 2002 00:43:00 -0000 1.2
@@ -1,8 +1,8 @@
<section id="vorbis-spec-floor1">
<sectioninfo>
<releaseinfo>
- $Id: 07-floor1.xml,v 1.1 2002/10/12 20:37:11 giles Exp $
- <emphasis>Last update to this document: September 19, 2002</emphasis>
+ $Id: 07-floor1.xml,v 1.2 2002/10/18 00:43:00 giles Exp $
+ <emphasis>Last update to this document: October 15, 2002</emphasis>
</releaseinfo>
</sectioninfo>
<title>floor type 1 setup and decode</title>
@@ -308,8 +308,8 @@
8) [high_neighbor_offset] = <link linkend="vorbis-spec-high_neighbor">high_neighbor</link>([floor1_X_list],[i])
9) [predicted] = <link linkend="vorbis-spec-render_point">render_point</link>( vector [floor1_X_list] element [low_neighbor_offset],
- vector [floor1_X_list] element [high_neighbor_offset],
vector [floor1_final_Y] element [low_neighbor_offset],
+ vector [floor1_X_list] element [high_neighbor_offset],
vector [floor1_final_Y] element [high_neighbor_offset],
vector [floor1_X_list] element [i] )
@@ -339,7 +339,7 @@
} else [hiroom] is not greater than [lowroom] {
- 23) vector [floor1_final_Y] element [i] = [predicted] - ([val] - [lowroom]) - 1
+ 23) vector [floor1_final_Y] element [i] = [predicted] - [val] + [hiroom] - 1
}
@@ -348,7 +348,7 @@
24) if ([val] is odd) {
25) vector [floor1_final_Y] element [i] =
- [predicted] - (([val] - 1) divided by 2 using integer division)
+ [predicted] - (([val] + 1) divided by 2 using integer division)
} else [val] is even {
@@ -409,22 +409,22 @@
6) [hy] = [floor1_final_Y]' element [i] * [floor1_multiplier]
7) [hx] = [floor1_X_list]' element [i]
- 8) <link linkend="vorbis-spec-render_line">render_line</link>( [lx], [hx], [ly], [hy], [floor] )
+ 8) <link linkend="vorbis-spec-render_line">render_line</link>( [lx], [ly], [hx], [hy], [floor] )
9) [lx] = [hx]
10) [ly] = [hy]
}
+ }
- 11) if ( [hx] is less than [n] ) {
+ 11) if ( [hx] is less than [n] ) {
- 12) <link linkend="vorbis-spec-render_line">render_line</link>( [hx], [hy], [n], [hy], [floor] )
+ 12) <link linkend="vorbis-spec-render_line">render_line</link>( [hx], [hy], [n], [hy], [floor] )
- }
+ }
- 13) if ( [hx] is greater than [n] ) {
+ 13) if ( [hx] is greater than [n] ) {
14) truncate vector [floor] to [n] elements
- }
}
15) for each scalar in vector [floor], perform a lookup substitution using
<p><p>1.4 +1 -1 vorbis/doc/xml/Vorbis_I_spec.xml
Index: Vorbis_I_spec.xml
===================================================================
RCS file: /usr/local/cvsroot/vorbis/doc/xml/Vorbis_I_spec.xml,v
retrieving revision 1.3
retrieving revision 1.4
diff -u -r1.3 -r1.4
--- Vorbis_I_spec.xml 16 Oct 2002 23:22:46 -0000 1.3
+++ Vorbis_I_spec.xml 18 Oct 2002 00:43:00 -0000 1.4
@@ -15,7 +15,7 @@
<!ENTITY oggvorbis SYSTEM "a1-encapsulation_ogg.xml">
<!ENTITY rtpvorbis SYSTEM "a2-encapsulation_rtp.xml">
<!ENTITY footer SYSTEM "footer.xml">
-<!ENTITY draft-rtp SYSTEM "../draft-moffitt-vorbis-rtp-00.txt" NDATA TXT>
+<!ENTITY draft-rtp SYSTEM "../draft-moffitt-vorbis-rtp-00.txt">
]>
<article>
<p><p>--- >8 ----
List archives: http://www.xiph.org/archives/
Ogg project homepage: http://www.xiph.org/ogg/
To unsubscribe from this list, send a message to 'cvs-request at xiph.org'
containing only the word 'unsubscribe' in the body. No subject is needed.
Unsubscribe messages sent to the list will be ignored/filtered.
More information about the commits
mailing list