<?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>chnget</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="chnexport.html" title="chnexport" /> <link rel="next" href="chnmix.html" title="chnmix" /> </head> <body> <div class="navheader"> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">chnget</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="chnexport.html">Prev</a> </td> <th width="60%" align="center">Orchestra Opcodes and Operators</th> <td width="20%" align="right"> <a accesskey="n" href="chnmix.html">Next</a></td> </tr> </table> <hr /> </div> <div class="refentry"> <a id="chnget"></a> <div class="titlepage"></div> <a id="Indexchnget" class="indexterm"></a> <div class="refnamediv"> <h2> <span class="refentrytitle">chnget</span> </h2> <p>chnget — Reads data from the software bus. </p> </div> <div class="refsect1"> <a id="idm281472947008440"></a> <h2>Description</h2> <p> Reads data from a channel of the inward named software bus. Implies declaring the channel with <span class="emphasis"><em>imode</em></span>=1 (see also <a class="link" href="chn.html" title="chn"><em class="citetitle">chn_k, chn_a, and chn_S</em></a>). </p> </div> <div class="refsect1"> <a id="idm281472946963352"></a> <h2>Syntax</h2> <pre class="synopsis">ival <span class="command"><strong>chnget</strong></span> Sname</pre> <pre class="synopsis">kval <span class="command"><strong>chnget</strong></span> Sname</pre> <pre class="synopsis">aval <span class="command"><strong>chnget</strong></span> Sname</pre> <pre class="synopsis">Sval <span class="command"><strong>chnget</strong></span> Sname</pre> <pre class="synopsis">Sval <span class="command"><strong>chngetks</strong></span> Sname</pre> </div> <div class="refsect1"> <a id="idm281472946955512"></a> <h2>Initialization</h2> <p> <span class="emphasis"><em>Sname</em></span> -- a string that identifies a channel of the named software bus to read. </p> <p> <span class="emphasis"><em>ival</em></span> -- the control value read at i-time. </p> <p> <span class="emphasis"><em>Sval</em></span> -- the string value read at i-time. </p> </div> <div class="refsect1"> <a id="idm281472946952184"></a> <h2>Performance</h2> <p> <span class="emphasis"><em>kval</em></span> -- the control value read at performance time. </p> <p> <span class="emphasis"><em>aval</em></span> -- the audio signal read at performance time. </p> <p> <span class="emphasis"><em>Sval</em></span> -- the string value read at k-rate. The chnget opcode works both at i-time and perf-time, whereas chngetks works only at perf-time. String variables are only updated if the channel has changed. </p> </div> <div class="refsect1"> <a id="idm281472946948616"></a> <h2>Example</h2> <p> The example shows the software bus being used as an asynchronous control signal to select a filter cutoff. It assumes that an external program that has access to the API is feeding the values. </p> <div class="informalexample"> <pre class="programlisting"> <span class="ohdr">sr</span> <span class="op">=</span> 44100 <span class="ohdr">kr</span> <span class="op">=</span> 100 <span class="ohdr">ksmps</span> <span class="op">=</span> 1 <span class="oblock">instr</span> 1 kc <span class="opc">chnget</span> "cutoff" a1 <span class="opc">oscil</span> p4, p5, 100 a2 <span class="opc">lowpass2</span> a1, kc, 200 <span class="opc">out</span> a2 <span class="oblock">endin</span> </pre> </div> <p> Here is another example of the chnget opcode. It uses the file <a class="ulink" href="examples/chnget.csd" target="_top"><em class="citetitle">chnget.csd</em></a>. </p> <div class="example"> <a id="idm281472946937032"></a> <p class="title"> <strong>Example 123. Example of the chnget opcode.</strong> </p> <div class="example-contents"> <div class="refsect1"> <a id="idm281472780859720"></a> <pre class="programlisting"> <span class="nt"><CsoundSynthesizer></span> <span class="nt"><CsOptions></span> <span class="c1">; Select audio/midi flags here according to platform</span> -odac <span class="c1">;;;realtime audio out</span> <span class="c1">;-iadc ;;;uncomment -iadc if realtime audio input is needed too</span> <span class="c1">; For Non-realtime ouput leave only the line below:</span> <span class="c1">; -o chnget.wav -W ;;; for file output any platform</span> <span class="nt"></CsOptions></span> <span class="nt"><CsInstruments></span> <span class="c1">;Example by Joachim Heintz</span> <span class="vg">sr</span> <span class="o">=</span> <span class="mi">44100</span> <span class="vg">ksmps</span> <span class="o">=</span> <span class="mi">32</span> <span class="vg">nchnls</span> <span class="o">=</span> <span class="mi">2</span> <span class="vg">0dbfs</span> <span class="o">=</span> <span class="mi">1</span> <span class="kd">instr</span> <span class="nf">1</span><span class="c1">; send i-values</span> <span class="nb">chnset</span> <span class="mi">1</span><span class="p">,</span> <span class="s">"sio"</span> <span class="nb">chnset</span> <span class="o">-</span><span class="mi">1</span><span class="p">,</span> <span class="s">"non"</span> <span class="kd">endin</span> <span class="kd">instr</span> <span class="nf">2</span><span class="c1">; send k-values</span> k<span class="n">freq</span> <span class="nb">randomi</span> <span class="mi">100</span><span class="p">,</span> <span class="mi">300</span><span class="p">,</span> <span class="mi">1</span> <span class="nb">chnset</span> k<span class="n">freq</span><span class="p">,</span> <span class="s">"cntrfreq"</span> k<span class="n">bw</span> <span class="o">=</span> k<span class="n">freq</span><span class="o">/</span><span class="mi">10</span> <span class="nb">chnset</span> k<span class="n">bw</span><span class="p">,</span> <span class="s">"bandw"</span> <span class="kd">endin</span> <span class="kd">instr</span> <span class="nf">3</span><span class="c1">; send a-values</span> a<span class="n">nois</span> <span class="nb">rand</span> <span class="mf">.1</span> <span class="nb">chnset</span> a<span class="n">nois</span><span class="p">,</span> <span class="s">"noise"</span> <span class="nl">loop</span><span class="p">:</span> i<span class="n">dur</span> <span class="nb">random</span> <span class="mf">.3</span><span class="p">,</span> <span class="mf">1.5</span> <span class="k">timout</span> <span class="mi">0</span><span class="p">,</span> i<span class="n">dur</span><span class="p">,</span> <span class="k">do</span> <span class="nb">reinit</span> <span class="n">loop</span> <span class="nl">do</span><span class="p">:</span> i<span class="n">freq</span> <span class="nb">random</span> <span class="mi">400</span><span class="p">,</span> <span class="mi">1200</span> i<span class="n">amp</span> <span class="nb">random</span> <span class="mf">.1</span><span class="p">,</span> <span class="mf">.3</span> a<span class="n">sig</span> <span class="nb">oscils</span> i<span class="n">amp</span><span class="p">,</span> i<span class="n">freq</span><span class="p">,</span> <span class="mi">0</span> a<span class="n">env</span> <span class="nb">transeg</span> <span class="mi">1</span><span class="p">,</span> i<span class="n">dur</span><span class="p">,</span> <span class="o">-</span><span class="mi">10</span><span class="p">,</span> <span class="mi">0</span> a<span class="n">sine</span> <span class="o">=</span> a<span class="n">sig</span> <span class="o">*</span> a<span class="n">env</span> <span class="nb">chnset</span> a<span class="n">sine</span><span class="p">,</span> <span class="s">"sine"</span> <span class="kd">endin</span> <span class="kd">instr</span> <span class="nf">11</span><span class="c1">; receive some chn values and send again</span> i<span class="n">val1</span> <span class="nb">chnget</span> <span class="s">"sio"</span> i<span class="n">val2</span> <span class="nb">chnget</span> <span class="s">"non"</span> <span class="nb">print</span> i<span class="n">val1</span><span class="p">,</span> i<span class="n">val2</span> k<span class="n">cntfreq</span> <span class="nb">chnget</span> <span class="s">"cntrfreq"</span> k<span class="n">bandw</span> <span class="nb">chnget</span> <span class="s">"bandw"</span> a<span class="n">noise</span> <span class="nb">chnget</span> <span class="s">"noise"</span> a<span class="n">filt</span> <span class="nb">reson</span> a<span class="n">noise</span><span class="p">,</span> k<span class="n">cntfreq</span><span class="p">,</span> k<span class="n">bandw</span> a<span class="n">filt</span> <span class="nb">balance</span> a<span class="n">filt</span><span class="p">,</span> a<span class="n">noise</span> <span class="nb">chnset</span> a<span class="n">filt</span><span class="p">,</span> <span class="s">"filtered"</span> <span class="kd">endin</span> <span class="kd">instr</span> <span class="nf">12</span><span class="c1">; mix the two audio signals</span> a<span class="n">mix1</span> <span class="nb">chnget</span> <span class="s">"sine"</span> a<span class="n">mix2</span> <span class="nb">chnget</span> <span class="s">"filtered"</span> <span class="nb">chnmix</span> a<span class="n">mix1</span><span class="p">,</span> <span class="s">"mix"</span> <span class="nb">chnmix</span> a<span class="n">mix2</span><span class="p">,</span> <span class="s">"mix"</span> <span class="kd">endin</span> <span class="kd">instr</span> <span class="nf">20</span><span class="c1">; receive and reverb</span> a<span class="n">mix</span> <span class="nb">chnget</span> <span class="s">"mix"</span> a<span class="n">L</span><span class="p">,</span> a<span class="n">R</span> <span class="nb">freeverb</span> a<span class="n">mix</span><span class="p">,</span> a<span class="n">mix</span><span class="p">,</span> <span class="mf">.8</span><span class="p">,</span> <span class="mf">.5</span> <span class="nb">outs</span> a<span class="n">L</span><span class="p">,</span> a<span class="n">R</span> <span class="kd">endin</span> <span class="kd">instr</span> <span class="nf">100</span><span class="c1">; clear</span> <span class="nb">chnclear</span> <span class="s">"mix"</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">20</span> <span class="nb">i</span> <span class="mi">2</span> <span class="mi">0</span> <span class="mi">20</span> <span class="nb">i</span> <span class="mi">3</span> <span class="mi">0</span> <span class="mi">20</span> <span class="nb">i</span> <span class="mi">11</span> <span class="mi">0</span> <span class="mi">20</span> <span class="nb">i</span> <span class="mi">12</span> <span class="mi">0</span> <span class="mi">20</span> <span class="nb">i</span> <span class="mi">20</span> <span class="mi">0</span> <span class="mi">20</span> <span class="nb">i</span> <span class="mi">100</span> <span class="mi">0</span> <span class="mi">20</span> <span class="nt"></CsScore></span> <span class="nt"></CsoundSynthesizer></span> </pre> </div> </div> </div> <p><br class="example-break" /> </p> </div> <div class="refsect1"> <a id="idm281472946935112"></a> <h2>Credits</h2> <p> </p> <table border="0" summary="Simple list" class="simplelist"> <tr> <td>Author: Istvan Varga</td> </tr> <tr> <td>2005</td> </tr> </table> <p> </p> </div> </div> <div class="navfooter"> <hr /> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"><a accesskey="p" href="chnexport.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="chnmix.html">Next</a></td> </tr> <tr> <td width="40%" align="left" valign="top">chnexport </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> <td width="40%" align="right" valign="top"> chnmix</td> </tr> </table> </div> </body> </html>