ref: 40b954dcf3224a6352071834e7f92d07ef022816
parent: d62f378170a366d02b5b1bbc6d1f5868f6708455
author: Jean-Marc Valin <jmvalin@jmvalin.ca>
date: Fri Sep 23 19:29:40 EDT 2011
minor draft fixes
--- a/doc/draft-ietf-codec-opus.xml
+++ b/doc/draft-ietf-codec-opus.xml
@@ -5282,11 +5282,11 @@
The search for the best codevector y is performed by alg_quant()
(vq.c). There are several possible approaches to the
search, with a trade-off between quality and complexity. The method used in the reference
-implementation computes an initial codeword y1 by projecting the residual signal
-R = X - p' onto the codebook pyramid of K-1 pulses:
+implementation computes an initial codeword y1 by projecting the normalized spectrum
+X onto the codebook pyramid of K-1 pulses:
</t>
<t>
-y0 = round_towards_zero( (K-1) * R / sum(abs(R)))
+y0 = round_towards_zero( (K-1) * X / sum(abs(X)))
</t>
<t>
@@ -5293,11 +5293,11 @@
Depending on N, K and the input data, the initial codeword y0 may contain from
0 to K-1 non-zero values. All the remaining pulses, with the exception of the last one,
are found iteratively with a greedy search that minimizes the normalized correlation
-between y and R:
+between y and X:
<figure align="center">
<artwork align="center"><![CDATA[
T
-J = -R * y / ||y||
+J = -X * y / ||y||
]]></artwork>
</figure>
</t>
--
⑨