Help/UGens/Triggers/PeakFollower.html

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  26 <p class="p1"><span class="s1"><b>PeakFollower<span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span></b></span><b>track peak signal amplitude</b></p>
  27 <p class="p2"><br></p>
  28 <p class="p3"><b>PeakFollower.ar(in, decay)</b></p>
  29 <p class="p2"><br></p>
  30 <p class="p3">Outputs the peak amplitude of the signal received at the input.<span class="Apple-converted-space"> </span></p>
  31 <p class="p3">if level is below maximum, the level decreases by the factor given in decay.</p>
  32 <p class="p2"><br></p>
  33 <p class="p3"><b>in</b> - input signal.</p>
  34 <p class="p3"><b>decay</b> - decay factor.</p>
  35 <p class="p2"><br></p>
  36 <p class="p3">Internally, the absolute value of the signal is used, to prevent underreporting the peak value if there is a negative DC offset. To obtain the minimum and maximum values of the signal as is, use the <a href="RunningMin.html"><span class="s2">RunningMin</span></a> and <a href="RunningMax.html"><span class="s2">RunningMax</span></a> UGens.</p>
  37 <p class="p2"><br></p>
  38 <p class="p4">s.boot;</p>
  39 <p class="p5"><br></p>
  40 <p class="p6">// no decay</p>
  41 <p class="p4">(</p>
  42 <p class="p4">{<span class="Apple-converted-space"> </span></p>
  43 <p class="p7"><span class="s3"><span class="Apple-tab-span">    </span></span>SinOsc<span class="s3">.ar(</span></p>
  44 <p class="p4"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="s4">PeakFollower</span>.ar(<span class="s4">Dust</span>.ar(20, <span class="s4">Line</span>.kr(0, 1, 4)), 1.0) * 1500 + 200,<span class="Apple-converted-space"> </span></p>
  45 <p class="p4"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>0, 0.2</p>
  46 <p class="p4"><span class="Apple-tab-span">     </span>)</p>
  47 <p class="p8"><span class="Apple-tab-span">     </span></p>
  48 <p class="p4">}.play;</p>
  49 <p class="p4">)</p>
  50 <p class="p8"><br></p>
  51 <p class="p6">// a little decay</p>
  52 <p class="p4">(</p>
  53 <p class="p4">{<span class="Apple-converted-space"> </span></p>
  54 <p class="p7"><span class="s3"><span class="Apple-tab-span">    </span></span>SinOsc<span class="s3">.ar(</span></p>
  55 <p class="p4"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="s4">PeakFollower</span>.ar(<span class="s4">Dust</span>.ar(20, <span class="s4">Line</span>.kr(0, 1, 4)), 0.999) * 1500 + 200,<span class="Apple-converted-space"> </span></p>
  56 <p class="p4"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>0, 0.2</p>
  57 <p class="p4"><span class="Apple-tab-span">     </span>)</p>
  58 <p class="p8"><span class="Apple-tab-span">     </span></p>
  59 <p class="p4">}.play;</p>
  60 <p class="p4">)</p>
  61 <p class="p8"><br></p>
  62 <p class="p6">// mouse x controls decay, center of the</p>
  63 <p class="p4">(</p>
  64 <p class="p4">{<span class="Apple-converted-space"> </span></p>
  65 <p class="p4"><span class="Apple-tab-span">     </span><span class="s4">var</span> decay;</p>
  66 <p class="p4"><span class="Apple-tab-span">     </span>decay = <span class="s4">MouseX</span>.kr(0.99, 1.00001).min(1.0);</p>
  67 <p class="p7"><span class="s3"><span class="Apple-tab-span">    </span></span>SinOsc<span class="s3">.ar(</span></p>
  68 <p class="p4"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="s4">PeakFollower</span>.ar(<span class="s4">Dust</span>.ar(20), decay) * 1500 + 200,<span class="Apple-converted-space"> </span></p>
  69 <p class="p4"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>0, 0.2</p>
  70 <p class="p4"><span class="Apple-tab-span">     </span>);</p>
  71 <p class="p8"><span class="Apple-tab-span">     </span></p>
  72 <p class="p4">}.play;</p>
  73 <p class="p4">)</p>
  74 <p class="p8"><br></p>
  75 <p class="p8"><br></p>
  76 <p class="p8"><br></p>
  77 <p class="p8"><br></p>
  78 <p class="p6">// follow a sine lfo, decay controlled by mouse x</p>
  79 <p class="p4">(</p>
  80 <p class="p4">{<span class="Apple-converted-space"> </span></p>
  81 <p class="p4"><span class="Apple-tab-span">     </span><span class="s4">var</span> decay;</p>
  82 <p class="p4"><span class="Apple-tab-span">     </span>decay = <span class="s4">MouseX</span>.kr(0, 1.1).min(1.0);</p>
  83 <p class="p7"><span class="s3"><span class="Apple-tab-span">    </span></span>SinOsc<span class="s3">.ar(</span></p>
  84 <p class="p4"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="s4">PeakFollower</span>.kr(<span class="s4">SinOsc</span>.kr(0.2), decay) * 200 + 500,<span class="Apple-converted-space"> </span></p>
  85 <p class="p4"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>0, 0.2</p>
  86 <p class="p4"><span class="Apple-tab-span">     </span>)</p>
  87 <p class="p8"><span class="Apple-tab-span">     </span></p>
  88 <p class="p4">}.play;</p>
  89 <p class="p4">)</p>
  90 <p class="p8"><br></p>
  91 <p class="p8"><br></p>
  92 <p class="p8"><br></p>
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