Help/UGens/FFT/PV_MagShift.html

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  26 <p class="p1"><b>PV_MagShift<span class="Apple-tab-span">       </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>shift and stretch magnitude bin position</b></p>
  27 <p class="p2"><br></p>
  28 <p class="p3"><b>PV_MagShift(buffer,<span class="Apple-converted-space">  </span>stretch,<span class="Apple-converted-space">  </span>shift)</b></p>
  29 <p class="p2"><br></p>
  30 <p class="p3">Shift and stretch the positions of only the magnitude of the bins.<span class="Apple-converted-space"> </span></p>
  31 <p class="p3">Can be used as a very crude frequency shifter/scaler.</p>
  32 <p class="p3"><b>buffer</b> - fft buffer.</p>
  33 <p class="p3"><b>stretch</b> - scale bin location by factor.</p>
  34 <p class="p3"><b>shift</b> - add an offset to bin position.</p>
  35 <p class="p2"><br></p>
  36 <p class="p4"><span class="s1">See also <a href="FFT Overview.html"><span class="s2">FFT Overview</span></a>.</span></p>
  37 <p class="p2"><br></p>
  38 <p class="p5">s.boot;</p>
  39 <p class="p6"><br></p>
  40 <p class="p5">(</p>
  41 <p class="p7"><span class="s3">SynthDef</span><span class="s1">(</span>"help-magStretch"<span class="s1">, { </span><span class="s3">arg</span><span class="s1"> out=0;</span></p>
  42 <p class="p5"><span class="Apple-tab-span">     </span><span class="s3">var</span> in, chain;</p>
  43 <p class="p5"><span class="Apple-tab-span">     </span>in = <span class="s3">LFSaw</span>.ar(200, 0, 0.2);</p>
  44 <p class="p5"><span class="Apple-tab-span">     </span>chain = <span class="s3">FFT</span>(<span class="s3">LocalBuf</span>(2048), in);</p>
  45 <p class="p5"><span class="Apple-tab-span">     </span>chain = <span class="s3">PV_MagShift</span>(chain, <span class="s3">MouseX</span>.kr(0.25, 4, <span class="s4">\exponential</span>) );<span class="Apple-converted-space"> </span></p>
  46 <p class="p5"><span class="Apple-tab-span">     </span><span class="s3">Out</span>.ar(out, 0.5 * <span class="s3">IFFT</span>(chain).dup);</p>
  47 <p class="p5">}).play;</p>
  48 <p class="p5">)</p>
  49 <p class="p6"><br></p>
  50 <p class="p5">(</p>
  51 <p class="p5"><span class="s3">SynthDef</span>(<span class="s5">"help-magStretch2"</span>, { <span class="s3">arg</span> out=0, soundBufnum=2;</p>
  52 <p class="p5"><span class="Apple-tab-span">     </span><span class="s3">var</span> in, chain;</p>
  53 <p class="p5"><span class="Apple-tab-span">     </span>in = <span class="s3">PlayBuf</span>.ar(1, soundBufnum, <span class="s3">BufRateScale</span>.kr(soundBufnum), loop: 1);</p>
  54 <p class="p5"><span class="Apple-tab-span">     </span>chain = <span class="s3">FFT</span>(<span class="s3">LocalBuf</span>(2048), in);</p>
  55 <p class="p5"><span class="Apple-tab-span">     </span>chain = <span class="s3">PV_MagShift</span>(chain, <span class="s3">MouseX</span>.kr(0.25, 4, <span class="s4">\exponential</span>) );<span class="Apple-converted-space"> </span></p>
  56 <p class="p5"><span class="Apple-tab-span">     </span><span class="s3">Out</span>.ar(out, 0.5 * <span class="s3">IFFT</span>(chain).dup);</p>
  57 <p class="p5">}).play(s,[<span class="s4">\out</span>, 0, <span class="s4">\soundBufnum</span>, c]);</p>
  58 <p class="p5">)</p>
  59 <p class="p6"><br></p>
  60 <p class="p5">(</p>
  61 <p class="p7"><span class="s3">SynthDef</span><span class="s1">(</span>"help-magShift"<span class="s1">, { </span><span class="s3">arg</span><span class="s1"> out=0;</span></p>
  62 <p class="p5"><span class="Apple-tab-span">     </span><span class="s3">var</span> in, chain;</p>
  63 <p class="p5"><span class="Apple-tab-span">     </span>in = <span class="s3">LFSaw</span>.ar(200, 0, 0.2);</p>
  64 <p class="p5"><span class="Apple-tab-span">     </span>chain = <span class="s3">FFT</span>(<span class="s3">LocalBuf</span>(2048), in);</p>
  65 <p class="p5"><span class="Apple-tab-span">     </span>chain = <span class="s3">PV_MagShift</span>(chain, 1, <span class="s3">MouseX</span>.kr(-128, 128) );<span class="Apple-converted-space"> </span></p>
  66 <p class="p5"><span class="Apple-tab-span">     </span><span class="s3">Out</span>.ar(out, 0.5 * <span class="s3">IFFT</span>(chain).dup);</p>
  67 <p class="p5">}).play;</p>
  68 <p class="p5">)</p>
  69 <p class="p6"><br></p>
  70 <p class="p6"><br></p>
  71 <p class="p7"><span class="s1">c = </span><span class="s3">Buffer</span><span class="s1">.read(s,</span>"sounds/a11wlk01.wav"<span class="s1">);</span></p>
  72 <p class="p6"><br></p>
  73 <p class="p5">(</p>
  74 <p class="p5"><span class="s3">SynthDef</span>(<span class="s5">"help-magShift2"</span>, {<span class="Apple-converted-space">  </span><span class="s3">arg</span> out=0, soundBufnum=2;</p>
  75 <p class="p5"><span class="Apple-tab-span">     </span><span class="s3">var</span> in, chain;</p>
  76 <p class="p5"><span class="Apple-tab-span">     </span>in = <span class="s3">PlayBuf</span>.ar(1, soundBufnum, <span class="s3">BufRateScale</span>.kr(soundBufnum), loop: 1);</p>
  77 <p class="p5"><span class="Apple-tab-span">     </span>chain = <span class="s3">FFT</span>(<span class="s3">LocalBuf</span>(2048), in);</p>
  78 <p class="p5"><span class="Apple-tab-span">     </span>chain = <span class="s3">PV_MagShift</span>(chain, 1, <span class="s3">MouseX</span>.kr(-128, 128) );<span class="Apple-converted-space"> </span></p>
  79 <p class="p5"><span class="Apple-tab-span">     </span><span class="s3">Out</span>.ar(out, 0.5 * <span class="s3">IFFT</span>(chain).dup);</p>
  80 <p class="p5">}).play(s,[<span class="s4">\out</span>, 0, <span class="s4">\soundBufnum</span>, c]);</p>
  81 <p class="p5">)</p>
  82 <p class="p6"><br></p>
  83 <p class="p5">c.free;</p>
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