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7<title>SetBiquadFilterCoefficients</title>
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9  <body>
10<h1><CODE><a href="../../../../nn/Overview.html">nn</a>::<a href="../../../../nn/snd/Overview.html">snd</a>::<a href="../../../../nn/snd/CTR/Overview.html">CTR</a>::<a href="../../../../nn/snd/CTR/Voice/Overview.html">Voice</a>::SetBiquadFilterCoefficients</CODE> Member Function</h1>
11<h2>Syntax</h2>
12    <div class="section">
13      <pre class="definition">
14void SetBiquadFilterCoefficients(
15     const <a href="../../../../nn/snd/CTR/BiquadFilterCoefficients/Overview.html">BiquadFilterCoefficients</a> & coeff
16);
17</pre>
18    </div>
19<h2>Arguments</h2>
20    <div class="section">
21      <table class="arguments">
22        <thead>
23          <tr>
24            <td width="15" />
25<th>Name</th>
26<td>Description</td>
27          </tr>
28        </thead>
29        <tr>
30<td>in</td>
31<th>coeff</th>
32<td>Coefficient buffer.</td>
33        </tr> </table>
34    </div>
35<h2>Return Values</h2>
36    <div class="section">
37None.
38               </div>
39<h2>Description</h2>
40    <div class="section">
41<p>Sets the coefficients for a biquad filter.</p><p>
42The biquad filter output and frequency characteristics are represented as follows.
43</p><p><pre>y(n) = n0 * x(n) + n1 * x(n-1) + n2 * x(n-2) + d1 * y(n-1) + d2 * y(n-2)</pre></p><p><pre>
44n0 + n1(Z^-1) + n2(Z^-2)
45H(z) = ----------------------------
461  - d1(Z^-1) - d2(Z^-2)</pre></p><p>
47The coefficients can all be specified as Q14-format 16-bit integers, comprising a 2-bit integer portion and a 14-bit fractional portion. Sounds may be clipped if the filter gain is higher than 1.
48      </p></div>
49<h2>Revision History</h2>
50    <div class="section">
51      <dl class="history">
52        <dt>2010/10/18</dt>
53<dd>Initial version.<br />
54        </dd>
55      </dl>
56    </div>
57  <hr><p>CONFIDENTIAL</p></body>
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59