1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
2<html>
3
4<head>
5<LINK rel="stylesheet" type="text/css" href="../../CSS/revolution.css">
6<title>axvpb.pb.srcSelect</title>
7<META http-equiv="Content-Type" content="text/html; charset=windows-1252">
8<META name="GENERATOR" content="IBM WebSphere Studio Homepage Builder Version 6.5.0.0 for Windows">
9<META http-equiv="Content-Style-Type" content="text/css">
10</head>
11
12<body>
13
14<h1 align="left">axvpb.pb.srcSelect</h1>
15
16
17<h2>C Specification</h2>
18<BLOCKQUOTE>
19<pre><CODE>#define AX_PB_SRCSEL_POLYPHASE  0x0000  // N64 type polyphase filter (4-tap)
20#define AX_PB_SRCSEL_LINEAR     0x0001  // Linear interpolator
21#define AX_PB_SRCSEL_NONE       0x0002  // No SRC (1:1)
22
23u16 srcSelect;</CODE></pre>
24</BLOCKQUOTE>
25<h2>Description</h2>
26
27<p>The <code>srcSelect</code> specifies which SRC (Sample Rate Converter) to use for the given voice:</p>
28
29<ul>
30<li><code>AX_PB_SRCSEL_POLYPHASE</code><br>This SRC applies a four-tap polyphase FIR filter to eliminate aliasing/imaging components. While providing a very 'clean' signal, the signal has a truncated frequency band as dictated by the coefficients of the filter. You must select the coefficients using the <code>axvpb.pb.coefSelect</code> parameter. It is very similar to the SRC commonly used in N64 applications.
31<li><code>AX_PB_SRCSEL_LINEAR</code><br> Linear interpolation. Highly recommended for most applications.
32<li><code>AX_PB_SRCSEL_NONE</code><br> This mode will bypass the SRC stage entirely. The mode is useful for samples which do not need to be pitch-shifted (e.g., software streams with 32-kHz sample rate). You must assert the <code>AX_SYNC_USER_SRCSELECT</code> synchronization flag in <code>axvpb.sync</code>, when setting a new <code>srcSelect</code> type.
33</ul>
34
35<h2>See Also</h2>
36<p>
37<code><a href="../Voice_Parameter_Blocks/sync.html">axvpb.sync</a><br> <a href="coefselect.html">axvpb.pb.coefSelect</a><br> <a href="../Voice_Parameters/AXSetVoiceSrcType.html">AXSetVoiceSrcType</a></code>
38</p>
39
40<h2>Revision History</h2>
41
42<P>2006/03/01 Initial version.</P><hr>
43<P>CONFIDENTIAL</p>
44</BODY>
45</HTML>
46