[xiph-cvs] cvs commit: vorbis/doc vorbis-spec-ref.html

[Monty]

xiphmont    02/09/20 05:52:31

  Modified:    doc      vorbis-spec-ref.html
  Log:
  Fix an off-by-one error reading angle and magnitude vector assignemtns
  in mapping decode.
  
  Monty

Revision  Changes    Path
1.5       +3 -3      vorbis/doc/vorbis-spec-ref.html

Index: vorbis-spec-ref.html
===================================================================
RCS file: /usr/local/cvsroot/vorbis/doc/vorbis-spec-ref.html,v
retrieving revision 1.4
retrieving revision 1.5
diff -u -r1.4 -r1.5
--- vorbis-spec-ref.html	9 Aug 2002 00:09:58 -0000	1.4
+++ vorbis-spec-ref.html	20 Sep 2002 09:52:31 -0000	1.5
@@ -6,7 +6,7 @@
 Ogg Vorbis I format specification: codec setup and packet decode
 </font></h1>
 
-Last update to this document: August 8, 2002</em><br>
+Last update to this document: September 20, 2002</em><br>
 
 <h1>Overview</h1>
 
@@ -172,8 +172,8 @@
               <ol><li><tt>[vorbis_mapping_coupling_steps]</tt>= read 8 bits as unsigned integer and add one<p>
                   <li>for <tt>[j]</tt> each of <tt>[vorbis_mapping_coupling_steps]</tt> steps:<p>
                       <ol>
-                      <li>vector <tt>[vorbis_mapping_magnitude]</tt> element <tt>[j]</tt>= read ilog([audio_channels]) bits as unsigned integer<p>
-                      <li>vector <tt>[vorbis_mapping_angle]</tt> element <tt>[j]</tt>= read ilog([audio_channels]) bits as unsigned integer<p>
+                      <li>vector <tt>[vorbis_mapping_magnitude]</tt> element <tt>[j]</tt>= read ilog([audio_channels] - 1) bits as unsigned integer<p>
+                      <li>vector <tt>[vorbis_mapping_angle]</tt> element <tt>[j]</tt>= read ilog([audio_channels] - 1) bits as unsigned integer<p>
                       <li>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 <tt>[audio_channels]</tt>-1, or the angle channel is greater than <tt>[audio_channels]</tt>-1, the stream is undecodable.<p>
                       </ol>
                </ol>

<p><p>--- >8 ----
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