<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>mfb</title>
<link rel="stylesheet" type="text/css" href="csound.css" />
<link rel="stylesheet" type="text/css" href="syntax-highlighting.css" />
<meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" />
<link rel="home" href="index.html" title="The Canonical Csound Reference Manual" />
<link rel="up" href="OpcodesTop.html" title="Orchestra Opcodes and Operators" />
<link rel="prev" href="metro.html" title="metro" />
<link rel="next" href="midglobal.html" title="midglobal" />
</head>
<body>
<div class="navheader">
<table width="100%" summary="Navigation header">
<tr>
<th colspan="3" align="center">mfb</th>
</tr>
<tr>
<td width="20%" align="left"><a accesskey="p" href="metro.html">Prev</a> </td>
<th width="60%" align="center">Orchestra Opcodes and Operators</th>
<td width="20%" align="right"> <a accesskey="n" href="midglobal.html">Next</a></td>
</tr>
</table>
<hr />
</div>
<div class="refentry">
<a id="mfb"></a>
<div class="titlepage"></div>
<a id="IndexMfb" class="indexterm"></a>
<div class="refnamediv">
<h2>
<span class="refentrytitle">mfb</span>
</h2>
<p>mfb —
Mel scale filterbank for spectral magnitudes.
</p>
</div>
<div class="refsect1">
<a id="idm281472915546792"></a>
<h2>Description</h2>
<p>
Applies a Mel scale filterbank to an array containing a series of magnitude bins.
</p>
</div>
<div class="refsect1">
<a id="idm281472915483176"></a>
<h2>Syntax</h2>
<pre class="synopsis">kout[] <span class="command"><strong>mfb</strong></span> kin[],klow,khigh,ibands</pre>
</div>
<div class="refsect1">
<a id="idm281472915481048"></a>
<h2>Initialization</h2>
<p>
<span class="emphasis"><em>ibands</em></span> -- number of bands in the Mel filter bank. Determines the size of
the output array.
</p>
</div>
<div class="refsect1">
<a id="idm281472915479336"></a>
<h2>Performance</h2>
<p>
<span class="emphasis"><em>kout[]</em></span> -- output array containing the MFB with ibands bands. It will be created if it does not exist.
</p>
<p>
<span class="emphasis"><em>kin[]</em></span> -- input array containing the input magnitude bins.
</p>
<p>
<span class="emphasis"><em>klow</em></span> -- lowest frequency (rounded to the nearest bin centre frequency).
</p>
<p>
<span class="emphasis"><em>khigh</em></span> -- highest lowest frequency (rounded to the nearest bin centre frequency).
</p>
</div>
<div class="refsect1">
<a id="idm281472915475032"></a>
<h2>Examples</h2>
<p>
Here is an example of the mfb opcode. It uses the file <a class="ulink" href="examples/mfb.csd" target="_top"><em class="citetitle">mfb.csd</em></a>.</p>
<div class="example">
<a id="idm281472915473080"></a>
<p class="title">
<strong>Example 534. Example of the mfb opcode.</strong>
</p>
<div class="example-contents">
<p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
<div class="refsect1">
<a id="idm281472739570584"></a>
<pre class="programlisting">
<span class="nt"><CsoundSynthesizer></span>
<span class="nt"><CsOptions></span>
<span class="nt"></CsOptions></span>
<span class="nt"><CsInstruments></span>
<span class="vg">ksmps</span> <span class="o">=</span> <span class="mi">64</span>
<span class="kd">instr</span> <span class="nf">1</span>
i<span class="n">fftsize</span> <span class="nb">init</span> <span class="mi">1024</span>
i<span class="n">bins</span> <span class="nb">init</span> i<span class="n">fftsize</span><span class="o">/</span><span class="mi">2</span>
k<span class="n">In</span><span class="p">[]</span> <span class="nb">init</span> i<span class="n">fftsize</span>
k<span class="n">cnt</span> <span class="nb">init</span> <span class="mi">0</span>
<span class="nb">p3</span> <span class="o">=</span> <span class="nb">filelen</span><span class="p">(</span><span class="s">"fox.wav"</span><span class="p">)</span>
a<span class="n">sig</span> <span class="nb">diskin</span> <span class="s">"fox.wav"</span>
k<span class="n">In</span> <span class="nb">shiftin</span> a<span class="n">sig</span>
k<span class="n">cnt</span> <span class="o">+=</span> <span class="vg">ksmps</span>
<span class="k">if</span> k<span class="n">cnt</span> <span class="o">==</span> i<span class="n">fftsize</span> <span class="k">then</span>
k<span class="n">FFT</span><span class="p">[]</span> <span class="o">=</span> <span class="nb">rfft</span><span class="p">(</span>k<span class="n">In</span><span class="p">)</span>
k<span class="n">Pows</span><span class="p">[]</span> <span class="o">=</span> <span class="nb">pows</span><span class="p">(</span>k<span class="n">FFT</span><span class="p">)</span>
k<span class="n">MFB</span><span class="p">[]</span> <span class="o">=</span> <span class="nb">log</span><span class="p">(</span><span class="nb">mfb</span><span class="p">(</span>k<span class="n">Pows</span><span class="p">,</span><span class="mi">300</span><span class="p">,</span><span class="mi">8000</span><span class="p">,</span><span class="mi">32</span><span class="p">))</span>
k<span class="n">mfcc</span><span class="p">[]</span> <span class="o">=</span> <span class="nb">dct</span><span class="p">(</span>k<span class="n">MFB</span><span class="p">)</span>
k<span class="n">cnt</span> <span class="o">=</span> <span class="mi">0</span>
k<span class="n">fb</span> <span class="o">=</span> <span class="mi">0</span>
<span class="k">while</span> k<span class="n">fb</span> <span class="o"><</span> <span class="mi">32</span> <span class="k">do</span>
<span class="nb">printf</span><span class="p">(</span><span class="s">"mfcc[</span><span class="si">%d</span><span class="s">] = %.3f </span><span class="se">\n</span><span class="s">"</span><span class="p">,</span> k<span class="n">fb</span><span class="o">+</span><span class="mi">1</span><span class="p">,</span> k<span class="n">fb</span><span class="p">,</span> k<span class="n">mfcc</span><span class="p">[</span>k<span class="n">fb</span><span class="p">])</span>
k<span class="n">fb</span> <span class="o">+=</span> <span class="mi">1</span>
<span class="k">od</span>
<span class="k">endif</span>
<span class="kd">endin</span>
<span class="nt"></CsInstruments></span>
<span class="nt"><CsScore></span>
<span class="nb">i</span><span class="mi">1</span> <span class="mi">0</span> <span class="mi">1</span>
<span class="nt"></CsScore></span>
<span class="nt"></CsoundSynthesizer></span>
</pre>
</div>
</div>
</div>
<br class="example-break" />
</div>
<div class="refsect1">
<a id="idm281472915468920"></a>
<h2>See Also</h2>
<p>
<a class="link" href="vectorial.html" title="Vectorial Opcodes"><em class="citetitle"></em>Vectorial opcodes</a>,
<a class="link" href="arrayOpcodes.html" title="Array Opcodes"><em class="citetitle"></em>array opcodes</a>,
<a class="link" href="dct.html" title="dct"><em class="citetitle">dct</em></a>
</p>
</div>
<div class="refsect1">
<a id="idm281472915464984"></a>
<h2>Credits</h2>
<p>
</p>
<table border="0" summary="Simple list" class="simplelist">
<tr>
<td>Author: Victor Lazzarini</td>
</tr>
<tr>
<td>NUI Maynooth</td>
</tr>
<tr>
<td>2016</td>
</tr>
</table>
<p>
</p>
<p>New in version 6.08</p>
</div>
</div>
<div class="navfooter">
<hr />
<table width="100%" summary="Navigation footer">
<tr>
<td width="40%" align="left"><a accesskey="p" href="metro.html">Prev</a> </td>
<td width="20%" align="center">
<a accesskey="u" href="OpcodesTop.html">Up</a>
</td>
<td width="40%" align="right"> <a accesskey="n" href="midglobal.html">Next</a></td>
</tr>
<tr>
<td width="40%" align="left" valign="top">metro </td>
<td width="20%" align="center">
<a accesskey="h" href="index.html">Home</a>
</td>
<td width="40%" align="right" valign="top"> midglobal</td>
</tr>
</table>
</div>
</body>
</html>
distrib
>
Mageia
>
7
>
armv7hl
>
media
>
core-release
>
by-pkgid
>
5fcfcb7517038d1f44ab4e478e6e61fa
>
files
>
2448
